/**************************************************************************/
/*  image.cpp                                                             */
/**************************************************************************/
/*                         This file is part of:                          */
/*                             GODOT ENGINE                               */
/*                        https://godotengine.org                         */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
/*                                                                        */
/* Permission is hereby granted, free of charge, to any person obtaining  */
/* a copy of this software and associated documentation files (the        */
/* "Software"), to deal in the Software without restriction, including    */
/* without limitation the rights to use, copy, modify, merge, publish,    */
/* distribute, sublicense, and/or sell copies of the Software, and to     */
/* permit persons to whom the Software is furnished to do so, subject to  */
/* the following conditions:                                              */
/*                                                                        */
/* The above copyright notice and this permission notice shall be         */
/* included in all copies or substantial portions of the Software.        */
/*                                                                        */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
/**************************************************************************/

#include "image.h"

#include "core/error/error_list.h"
#include "core/error/error_macros.h"
#include "core/io/image_loader.h"
#include "core/io/resource_loader.h"
#include "core/math/math_funcs.h"
#include "core/string/print_string.h"
#include "core/templates/hash_map.h"
#include "core/variant/dictionary.h"

#include <stdio.h>
#include <cmath>

const char *Image::format_names[Image::FORMAT_MAX] = {
	"Lum8", //luminance
	"LumAlpha8", //luminance-alpha
	"Red8",
	"RedGreen",
	"RGB8",
	"RGBA8",
	"RGBA4444",
	"RGBA5551",
	"RFloat", //float
	"RGFloat",
	"RGBFloat",
	"RGBAFloat",
	"RHalf", //half float
	"RGHalf",
	"RGBHalf",
	"RGBAHalf",
	"RGBE9995",
	"DXT1 RGB8", //s3tc
	"DXT3 RGBA8",
	"DXT5 RGBA8",
	"RGTC Red8",
	"RGTC RedGreen8",
	"BPTC_RGBA",
	"BPTC_RGBF",
	"BPTC_RGBFU",
	"ETC", //etc1
	"ETC2_R11", //etc2
	"ETC2_R11S", //signed", NOT srgb.
	"ETC2_RG11",
	"ETC2_RG11S",
	"ETC2_RGB8",
	"ETC2_RGBA8",
	"ETC2_RGB8A1",
	"ETC2_RA_AS_RG",
	"FORMAT_DXT5_RA_AS_RG",
	"ASTC_4x4",
	"ASTC_4x4_HDR",
	"ASTC_8x8",
	"ASTC_8x8_HDR",
};

SavePNGFunc Image::save_png_func = nullptr;
SaveJPGFunc Image::save_jpg_func = nullptr;
SaveEXRFunc Image::save_exr_func = nullptr;

SavePNGBufferFunc Image::save_png_buffer_func = nullptr;
SaveEXRBufferFunc Image::save_exr_buffer_func = nullptr;
SaveJPGBufferFunc Image::save_jpg_buffer_func = nullptr;

SaveWebPFunc Image::save_webp_func = nullptr;
SaveWebPBufferFunc Image::save_webp_buffer_func = nullptr;

void Image::_put_pixelb(int p_x, int p_y, uint32_t p_pixel_size, uint8_t *p_data, const uint8_t *p_pixel) {
	uint32_t ofs = (p_y * width + p_x) * p_pixel_size;
	memcpy(p_data + ofs, p_pixel, p_pixel_size);
}

void Image::_get_pixelb(int p_x, int p_y, uint32_t p_pixel_size, const uint8_t *p_data, uint8_t *p_pixel) {
	uint32_t ofs = (p_y * width + p_x) * p_pixel_size;
	memcpy(p_pixel, p_data + ofs, p_pixel_size);
}

int Image::get_format_pixel_size(Format p_format) {
	switch (p_format) {
		case FORMAT_L8:
			return 1; //luminance
		case FORMAT_LA8:
			return 2; //luminance-alpha
		case FORMAT_R8:
			return 1;
		case FORMAT_RG8:
			return 2;
		case FORMAT_RGB8:
			return 3;
		case FORMAT_RGBA8:
			return 4;
		case FORMAT_RGBA4444:
			return 2;
		case FORMAT_RGB565:
			return 2;
		case FORMAT_RF:
			return 4; //float
		case FORMAT_RGF:
			return 8;
		case FORMAT_RGBF:
			return 12;
		case FORMAT_RGBAF:
			return 16;
		case FORMAT_RH:
			return 2; //half float
		case FORMAT_RGH:
			return 4;
		case FORMAT_RGBH:
			return 6;
		case FORMAT_RGBAH:
			return 8;
		case FORMAT_RGBE9995:
			return 4;
		case FORMAT_DXT1:
			return 1; //s3tc bc1
		case FORMAT_DXT3:
			return 1; //bc2
		case FORMAT_DXT5:
			return 1; //bc3
		case FORMAT_RGTC_R:
			return 1; //bc4
		case FORMAT_RGTC_RG:
			return 1; //bc5
		case FORMAT_BPTC_RGBA:
			return 1; //btpc bc6h
		case FORMAT_BPTC_RGBF:
			return 1; //float /
		case FORMAT_BPTC_RGBFU:
			return 1; //unsigned float
		case FORMAT_ETC:
			return 1; //etc1
		case FORMAT_ETC2_R11:
			return 1; //etc2
		case FORMAT_ETC2_R11S:
			return 1; //signed: return 1; NOT srgb.
		case FORMAT_ETC2_RG11:
			return 1;
		case FORMAT_ETC2_RG11S:
			return 1;
		case FORMAT_ETC2_RGB8:
			return 1;
		case FORMAT_ETC2_RGBA8:
			return 1;
		case FORMAT_ETC2_RGB8A1:
			return 1;
		case FORMAT_ETC2_RA_AS_RG:
			return 1;
		case FORMAT_DXT5_RA_AS_RG:
			return 1;
		case FORMAT_ASTC_4x4:
			return 1;
		case FORMAT_ASTC_4x4_HDR:
			return 1;
		case FORMAT_ASTC_8x8:
			return 1;
		case FORMAT_ASTC_8x8_HDR:
			return 1;
		case FORMAT_MAX: {
		}
	}
	return 0;
}

void Image::get_format_min_pixel_size(Format p_format, int &r_w, int &r_h) {
	switch (p_format) {
		case FORMAT_DXT1: //s3tc bc1
		case FORMAT_DXT3: //bc2
		case FORMAT_DXT5: //bc3
		case FORMAT_RGTC_R: //bc4
		case FORMAT_RGTC_RG: { //bc5		case case FORMAT_DXT1:

			r_w = 4;
			r_h = 4;
		} break;
		case FORMAT_ETC: {
			r_w = 4;
			r_h = 4;
		} break;
		case FORMAT_BPTC_RGBA:
		case FORMAT_BPTC_RGBF:
		case FORMAT_BPTC_RGBFU: {
			r_w = 4;
			r_h = 4;
		} break;
		case FORMAT_ETC2_R11: //etc2
		case FORMAT_ETC2_R11S: //signed: NOT srgb.
		case FORMAT_ETC2_RG11:
		case FORMAT_ETC2_RG11S:
		case FORMAT_ETC2_RGB8:
		case FORMAT_ETC2_RGBA8:
		case FORMAT_ETC2_RGB8A1:
		case FORMAT_ETC2_RA_AS_RG:
		case FORMAT_DXT5_RA_AS_RG: {
			r_w = 4;
			r_h = 4;

		} break;
		case FORMAT_ASTC_4x4:
		case FORMAT_ASTC_4x4_HDR: {
			r_w = 4;
			r_h = 4;

		} break;
		case FORMAT_ASTC_8x8:
		case FORMAT_ASTC_8x8_HDR: {
			r_w = 8;
			r_h = 8;

		} break;
		default: {
			r_w = 1;
			r_h = 1;
		} break;
	}
}

int Image::get_format_pixel_rshift(Format p_format) {
	if (p_format == FORMAT_ASTC_8x8) {
		return 2;
	} else if (p_format == FORMAT_DXT1 || p_format == FORMAT_RGTC_R || p_format == FORMAT_ETC || p_format == FORMAT_ETC2_R11 || p_format == FORMAT_ETC2_R11S || p_format == FORMAT_ETC2_RGB8 || p_format == FORMAT_ETC2_RGB8A1) {
		return 1;
	} else {
		return 0;
	}
}

int Image::get_format_block_size(Format p_format) {
	switch (p_format) {
		case FORMAT_DXT1: //s3tc bc1
		case FORMAT_DXT3: //bc2
		case FORMAT_DXT5: //bc3
		case FORMAT_RGTC_R: //bc4
		case FORMAT_RGTC_RG: { //bc5		case case FORMAT_DXT1:

			return 4;
		}
		case FORMAT_ETC: {
			return 4;
		}
		case FORMAT_BPTC_RGBA:
		case FORMAT_BPTC_RGBF:
		case FORMAT_BPTC_RGBFU: {
			return 4;
		}
		case FORMAT_ETC2_R11: //etc2
		case FORMAT_ETC2_R11S: //signed: NOT srgb.
		case FORMAT_ETC2_RG11:
		case FORMAT_ETC2_RG11S:
		case FORMAT_ETC2_RGB8:
		case FORMAT_ETC2_RGBA8:
		case FORMAT_ETC2_RGB8A1:
		case FORMAT_ETC2_RA_AS_RG: //used to make basis universal happy
		case FORMAT_DXT5_RA_AS_RG: //used to make basis universal happy

		{
			return 4;
		}
		case FORMAT_ASTC_4x4:
		case FORMAT_ASTC_4x4_HDR: {
			return 4;
		}
		case FORMAT_ASTC_8x8:
		case FORMAT_ASTC_8x8_HDR: {
			return 8;
		}
		default: {
		}
	}

	return 1;
}

void Image::_get_mipmap_offset_and_size(int p_mipmap, int &r_offset, int &r_width, int &r_height) const {
	int w = width;
	int h = height;
	int ofs = 0;

	int pixel_size = get_format_pixel_size(format);
	int pixel_rshift = get_format_pixel_rshift(format);
	int block = get_format_block_size(format);
	int minw, minh;
	get_format_min_pixel_size(format, minw, minh);

	for (int i = 0; i < p_mipmap; i++) {
		int bw = w % block != 0 ? w + (block - w % block) : w;
		int bh = h % block != 0 ? h + (block - h % block) : h;

		int s = bw * bh;

		s *= pixel_size;
		s >>= pixel_rshift;
		ofs += s;
		w = MAX(minw, w >> 1);
		h = MAX(minh, h >> 1);
	}

	r_offset = ofs;
	r_width = w;
	r_height = h;
}

int Image::get_mipmap_offset(int p_mipmap) const {
	ERR_FAIL_INDEX_V(p_mipmap, get_mipmap_count() + 1, -1);

	int ofs, w, h;
	_get_mipmap_offset_and_size(p_mipmap, ofs, w, h);
	return ofs;
}

int Image::get_mipmap_byte_size(int p_mipmap) const {
	ERR_FAIL_INDEX_V(p_mipmap, get_mipmap_count() + 1, -1);

	int ofs, w, h;
	_get_mipmap_offset_and_size(p_mipmap, ofs, w, h);
	int ofs2;
	_get_mipmap_offset_and_size(p_mipmap + 1, ofs2, w, h);
	return ofs2 - ofs;
}

void Image::get_mipmap_offset_and_size(int p_mipmap, int &r_ofs, int &r_size) const {
	int ofs, w, h;
	_get_mipmap_offset_and_size(p_mipmap, ofs, w, h);
	int ofs2;
	_get_mipmap_offset_and_size(p_mipmap + 1, ofs2, w, h);
	r_ofs = ofs;
	r_size = ofs2 - ofs;
}

void Image::get_mipmap_offset_size_and_dimensions(int p_mipmap, int &r_ofs, int &r_size, int &w, int &h) const {
	int ofs;
	_get_mipmap_offset_and_size(p_mipmap, ofs, w, h);
	int ofs2, w2, h2;
	_get_mipmap_offset_and_size(p_mipmap + 1, ofs2, w2, h2);
	r_ofs = ofs;
	r_size = ofs2 - ofs;
}

Image::Image3DValidateError Image::validate_3d_image(Image::Format p_format, int p_width, int p_height, int p_depth, bool p_mipmaps, const Vector<Ref<Image>> &p_images) {
	int w = p_width;
	int h = p_height;
	int d = p_depth;

	int arr_ofs = 0;

	while (true) {
		for (int i = 0; i < d; i++) {
			int idx = i + arr_ofs;
			if (idx >= p_images.size()) {
				return VALIDATE_3D_ERR_MISSING_IMAGES;
			}
			if (p_images[idx].is_null() || p_images[idx]->is_empty()) {
				return VALIDATE_3D_ERR_IMAGE_EMPTY;
			}
			if (p_images[idx]->get_format() != p_format) {
				return VALIDATE_3D_ERR_IMAGE_FORMAT_MISMATCH;
			}
			if (p_images[idx]->get_width() != w || p_images[idx]->get_height() != h) {
				return VALIDATE_3D_ERR_IMAGE_SIZE_MISMATCH;
			}
			if (p_images[idx]->has_mipmaps()) {
				return VALIDATE_3D_ERR_IMAGE_HAS_MIPMAPS;
			}
		}

		arr_ofs += d;

		if (!p_mipmaps) {
			break;
		}

		if (w == 1 && h == 1 && d == 1) {
			break;
		}

		w = MAX(1, w >> 1);
		h = MAX(1, h >> 1);
		d = MAX(1, d >> 1);
	}

	if (arr_ofs != p_images.size()) {
		return VALIDATE_3D_ERR_EXTRA_IMAGES;
	}

	return VALIDATE_3D_OK;
}

String Image::get_3d_image_validation_error_text(Image3DValidateError p_error) {
	switch (p_error) {
		case VALIDATE_3D_OK: {
			return "Ok";
		} break;
		case VALIDATE_3D_ERR_IMAGE_EMPTY: {
			return "Empty Image found";
		} break;
		case VALIDATE_3D_ERR_MISSING_IMAGES: {
			return "Missing Images";
		} break;
		case VALIDATE_3D_ERR_EXTRA_IMAGES: {
			return "Too many Images";
		} break;
		case VALIDATE_3D_ERR_IMAGE_SIZE_MISMATCH: {
			return "Image size mismatch";
		} break;
		case VALIDATE_3D_ERR_IMAGE_FORMAT_MISMATCH: {
			return "Image format mismatch";
		} break;
		case VALIDATE_3D_ERR_IMAGE_HAS_MIPMAPS: {
			return "Image has included mipmaps";
		} break;
	}
	return String();
}

int Image::get_width() const {
	return width;
}

int Image::get_height() const {
	return height;
}

Size2i Image::get_size() const {
	return Size2i(width, height);
}

bool Image::has_mipmaps() const {
	return mipmaps;
}

int Image::get_mipmap_count() const {
	if (mipmaps) {
		return get_image_required_mipmaps(width, height, format);
	} else {
		return 0;
	}
}

//using template generates perfectly optimized code due to constant expression reduction and unused variable removal present in all compilers
template <uint32_t read_bytes, bool read_alpha, uint32_t write_bytes, bool write_alpha, bool read_gray, bool write_gray>
static void _convert(int p_width, int p_height, const uint8_t *p_src, uint8_t *p_dst) {
	constexpr uint32_t max_bytes = MAX(read_bytes, write_bytes);

	for (int y = 0; y < p_height; y++) {
		for (int x = 0; x < p_width; x++) {
			const uint8_t *rofs = &p_src[((y * p_width) + x) * (read_bytes + (read_alpha ? 1 : 0))];
			uint8_t *wofs = &p_dst[((y * p_width) + x) * (write_bytes + (write_alpha ? 1 : 0))];

			uint8_t rgba[4] = { 0, 0, 0, 255 };

			if constexpr (read_gray) {
				rgba[0] = rofs[0];
				rgba[1] = rofs[0];
				rgba[2] = rofs[0];
			} else {
				for (uint32_t i = 0; i < max_bytes; i++) {
					rgba[i] = (i < read_bytes) ? rofs[i] : 0;
				}
			}

			if constexpr (read_alpha || write_alpha) {
				rgba[3] = read_alpha ? rofs[read_bytes] : 255;
			}

			if constexpr (write_gray) {
				// REC.709
				const uint8_t luminance = (13938U * rgba[0] + 46869U * rgba[1] + 4729U * rgba[2] + 32768U) >> 16U;
				wofs[0] = luminance;
			} else {
				for (uint32_t i = 0; i < write_bytes; i++) {
					wofs[i] = rgba[i];
				}
			}

			if constexpr (write_alpha) {
				wofs[write_bytes] = rgba[3];
			}
		}
	}
}

void Image::convert(Format p_new_format) {
	if (data.size() == 0) {
		return;
	}

	if (p_new_format == format) {
		return;
	}

	// Includes the main image.
	const int mipmap_count = get_mipmap_count() + 1;

	if (format > FORMAT_RGBE9995 || p_new_format > FORMAT_RGBE9995) {
		ERR_FAIL_MSG("Cannot convert to <-> from compressed formats. Use compress() and decompress() instead.");

	} else if (format > FORMAT_RGBA8 || p_new_format > FORMAT_RGBA8) {
		//use put/set pixel which is slower but works with non byte formats
		Image new_img(width, height, mipmaps, p_new_format);

		for (int mip = 0; mip < mipmap_count; mip++) {
			Ref<Image> src_mip = get_image_from_mipmap(mip);
			Ref<Image> new_mip = new_img.get_image_from_mipmap(mip);

			for (int y = 0; y < src_mip->height; y++) {
				for (int x = 0; x < src_mip->width; x++) {
					new_mip->set_pixel(x, y, src_mip->get_pixel(x, y));
				}
			}

			int mip_offset = 0;
			int mip_size = 0;
			new_img.get_mipmap_offset_and_size(mip, mip_offset, mip_size);

			memcpy(new_img.data.ptrw() + mip_offset, new_mip->data.ptr(), mip_size);
		}

		_copy_internals_from(new_img);

		return;
	}

	Image new_img(width, height, mipmaps, p_new_format);

	int conversion_type = format | p_new_format << 8;

	for (int mip = 0; mip < mipmap_count; mip++) {
		int mip_offset = 0;
		int mip_size = 0;
		int mip_width = 0;
		int mip_height = 0;
		get_mipmap_offset_size_and_dimensions(mip, mip_offset, mip_size, mip_width, mip_height);

		const uint8_t *rptr = data.ptr() + mip_offset;
		uint8_t *wptr = new_img.data.ptrw() + new_img.get_mipmap_offset(mip);

		switch (conversion_type) {
			case FORMAT_L8 | (FORMAT_LA8 << 8):
				_convert<1, false, 1, true, true, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_L8 | (FORMAT_R8 << 8):
				_convert<1, false, 1, false, true, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_L8 | (FORMAT_RG8 << 8):
				_convert<1, false, 2, false, true, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_L8 | (FORMAT_RGB8 << 8):
				_convert<1, false, 3, false, true, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_L8 | (FORMAT_RGBA8 << 8):
				_convert<1, false, 3, true, true, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_LA8 | (FORMAT_L8 << 8):
				_convert<1, true, 1, false, true, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_LA8 | (FORMAT_R8 << 8):
				_convert<1, true, 1, false, true, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_LA8 | (FORMAT_RG8 << 8):
				_convert<1, true, 2, false, true, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_LA8 | (FORMAT_RGB8 << 8):
				_convert<1, true, 3, false, true, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_LA8 | (FORMAT_RGBA8 << 8):
				_convert<1, true, 3, true, true, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_R8 | (FORMAT_L8 << 8):
				_convert<1, false, 1, false, false, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_R8 | (FORMAT_LA8 << 8):
				_convert<1, false, 1, true, false, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_R8 | (FORMAT_RG8 << 8):
				_convert<1, false, 2, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_R8 | (FORMAT_RGB8 << 8):
				_convert<1, false, 3, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_R8 | (FORMAT_RGBA8 << 8):
				_convert<1, false, 3, true, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RG8 | (FORMAT_L8 << 8):
				_convert<2, false, 1, false, false, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RG8 | (FORMAT_LA8 << 8):
				_convert<2, false, 1, true, false, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RG8 | (FORMAT_R8 << 8):
				_convert<2, false, 1, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RG8 | (FORMAT_RGB8 << 8):
				_convert<2, false, 3, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RG8 | (FORMAT_RGBA8 << 8):
				_convert<2, false, 3, true, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGB8 | (FORMAT_L8 << 8):
				_convert<3, false, 1, false, false, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGB8 | (FORMAT_LA8 << 8):
				_convert<3, false, 1, true, false, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGB8 | (FORMAT_R8 << 8):
				_convert<3, false, 1, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGB8 | (FORMAT_RG8 << 8):
				_convert<3, false, 2, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGB8 | (FORMAT_RGBA8 << 8):
				_convert<3, false, 3, true, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGBA8 | (FORMAT_L8 << 8):
				_convert<3, true, 1, false, false, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGBA8 | (FORMAT_LA8 << 8):
				_convert<3, true, 1, true, false, true>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGBA8 | (FORMAT_R8 << 8):
				_convert<3, true, 1, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGBA8 | (FORMAT_RG8 << 8):
				_convert<3, true, 2, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
			case FORMAT_RGBA8 | (FORMAT_RGB8 << 8):
				_convert<3, true, 3, false, false, false>(mip_width, mip_height, rptr, wptr);
				break;
		}
	}

	_copy_internals_from(new_img);
}

Image::Format Image::get_format() const {
	return format;
}

static double _bicubic_interp_kernel(double x) {
	x = ABS(x);

	double bc = 0;

	if (x <= 1) {
		bc = (1.5 * x - 2.5) * x * x + 1;
	} else if (x < 2) {
		bc = ((-0.5 * x + 2.5) * x - 4) * x + 2;
	}

	return bc;
}

template <int CC, class T>
static void _scale_cubic(const uint8_t *__restrict p_src, uint8_t *__restrict p_dst, uint32_t p_src_width, uint32_t p_src_height, uint32_t p_dst_width, uint32_t p_dst_height) {
	// get source image size
	int width = p_src_width;
	int height = p_src_height;
	double xfac = (double)width / p_dst_width;
	double yfac = (double)height / p_dst_height;
	// coordinates of source points and coefficients
	double ox, oy, dx, dy;
	int ox1, oy1, ox2, oy2;
	// destination pixel values
	// width and height decreased by 1
	int ymax = height - 1;
	int xmax = width - 1;
	// temporary pointer

	for (uint32_t y = 0; y < p_dst_height; y++) {
		// Y coordinates
		oy = (double)y * yfac - 0.5f;
		oy1 = (int)oy;
		dy = oy - (double)oy1;

		for (uint32_t x = 0; x < p_dst_width; x++) {
			// X coordinates
			ox = (double)x * xfac - 0.5f;
			ox1 = (int)ox;
			dx = ox - (double)ox1;

			// initial pixel value

			T *__restrict dst = ((T *)p_dst) + (y * p_dst_width + x) * CC;

			double color[CC];
			for (int i = 0; i < CC; i++) {
				color[i] = 0;
			}

			for (int n = -1; n < 3; n++) {
				// get Y coefficient
				[[maybe_unused]] double k1 = _bicubic_interp_kernel(dy - (double)n);

				oy2 = oy1 + n;
				if (oy2 < 0) {
					oy2 = 0;
				}
				if (oy2 > ymax) {
					oy2 = ymax;
				}

				for (int m = -1; m < 3; m++) {
					// get X coefficient
					[[maybe_unused]] double k2 = k1 * _bicubic_interp_kernel((double)m - dx);

					ox2 = ox1 + m;
					if (ox2 < 0) {
						ox2 = 0;
					}
					if (ox2 > xmax) {
						ox2 = xmax;
					}

					// get pixel of original image
					const T *__restrict p = ((T *)p_src) + (oy2 * p_src_width + ox2) * CC;

					for (int i = 0; i < CC; i++) {
						if constexpr (sizeof(T) == 2) { //half float
							color[i] = Math::half_to_float(p[i]);
						} else {
							color[i] += p[i] * k2;
						}
					}
				}
			}

			for (int i = 0; i < CC; i++) {
				if constexpr (sizeof(T) == 1) { //byte
					dst[i] = CLAMP(Math::fast_ftoi(color[i]), 0, 255);
				} else if constexpr (sizeof(T) == 2) { //half float
					dst[i] = Math::make_half_float(color[i]);
				} else {
					dst[i] = color[i];
				}
			}
		}
	}
}

template <int CC, class T>
static void _scale_bilinear(const uint8_t *__restrict p_src, uint8_t *__restrict p_dst, uint32_t p_src_width, uint32_t p_src_height, uint32_t p_dst_width, uint32_t p_dst_height) {
	enum {
		FRAC_BITS = 8,
		FRAC_LEN = (1 << FRAC_BITS),
		FRAC_HALF = (FRAC_LEN >> 1),
		FRAC_MASK = FRAC_LEN - 1
	};

	for (uint32_t i = 0; i < p_dst_height; i++) {
		// Add 0.5 in order to interpolate based on pixel center
		uint32_t src_yofs_up_fp = (i + 0.5) * p_src_height * FRAC_LEN / p_dst_height;
		// Calculate nearest src pixel center above current, and truncate to get y index
		uint32_t src_yofs_up = src_yofs_up_fp >= FRAC_HALF ? (src_yofs_up_fp - FRAC_HALF) >> FRAC_BITS : 0;
		uint32_t src_yofs_down = (src_yofs_up_fp + FRAC_HALF) >> FRAC_BITS;
		if (src_yofs_down >= p_src_height) {
			src_yofs_down = p_src_height - 1;
		}
		// Calculate distance to pixel center of src_yofs_up
		uint32_t src_yofs_frac = src_yofs_up_fp & FRAC_MASK;
		src_yofs_frac = src_yofs_frac >= FRAC_HALF ? src_yofs_frac - FRAC_HALF : src_yofs_frac + FRAC_HALF;

		uint32_t y_ofs_up = src_yofs_up * p_src_width * CC;
		uint32_t y_ofs_down = src_yofs_down * p_src_width * CC;

		for (uint32_t j = 0; j < p_dst_width; j++) {
			uint32_t src_xofs_left_fp = (j + 0.5) * p_src_width * FRAC_LEN / p_dst_width;
			uint32_t src_xofs_left = src_xofs_left_fp >= FRAC_HALF ? (src_xofs_left_fp - FRAC_HALF) >> FRAC_BITS : 0;
			uint32_t src_xofs_right = (src_xofs_left_fp + FRAC_HALF) >> FRAC_BITS;
			if (src_xofs_right >= p_src_width) {
				src_xofs_right = p_src_width - 1;
			}
			uint32_t src_xofs_frac = src_xofs_left_fp & FRAC_MASK;
			src_xofs_frac = src_xofs_frac >= FRAC_HALF ? src_xofs_frac - FRAC_HALF : src_xofs_frac + FRAC_HALF;

			src_xofs_left *= CC;
			src_xofs_right *= CC;

			for (uint32_t l = 0; l < CC; l++) {
				if constexpr (sizeof(T) == 1) { //uint8
					uint32_t p00 = p_src[y_ofs_up + src_xofs_left + l] << FRAC_BITS;
					uint32_t p10 = p_src[y_ofs_up + src_xofs_right + l] << FRAC_BITS;
					uint32_t p01 = p_src[y_ofs_down + src_xofs_left + l] << FRAC_BITS;
					uint32_t p11 = p_src[y_ofs_down + src_xofs_right + l] << FRAC_BITS;

					uint32_t interp_up = p00 + (((p10 - p00) * src_xofs_frac) >> FRAC_BITS);
					uint32_t interp_down = p01 + (((p11 - p01) * src_xofs_frac) >> FRAC_BITS);
					uint32_t interp = interp_up + (((interp_down - interp_up) * src_yofs_frac) >> FRAC_BITS);
					interp >>= FRAC_BITS;
					p_dst[i * p_dst_width * CC + j * CC + l] = uint8_t(interp);
				} else if constexpr (sizeof(T) == 2) { //half float

					float xofs_frac = float(src_xofs_frac) / (1 << FRAC_BITS);
					float yofs_frac = float(src_yofs_frac) / (1 << FRAC_BITS);
					const T *src = ((const T *)p_src);
					T *dst = ((T *)p_dst);

					float p00 = Math::half_to_float(src[y_ofs_up + src_xofs_left + l]);
					float p10 = Math::half_to_float(src[y_ofs_up + src_xofs_right + l]);
					float p01 = Math::half_to_float(src[y_ofs_down + src_xofs_left + l]);
					float p11 = Math::half_to_float(src[y_ofs_down + src_xofs_right + l]);

					float interp_up = p00 + (p10 - p00) * xofs_frac;
					float interp_down = p01 + (p11 - p01) * xofs_frac;
					float interp = interp_up + ((interp_down - interp_up) * yofs_frac);

					dst[i * p_dst_width * CC + j * CC + l] = Math::make_half_float(interp);
				} else if constexpr (sizeof(T) == 4) { //float

					float xofs_frac = float(src_xofs_frac) / (1 << FRAC_BITS);
					float yofs_frac = float(src_yofs_frac) / (1 << FRAC_BITS);
					const T *src = ((const T *)p_src);
					T *dst = ((T *)p_dst);

					float p00 = src[y_ofs_up + src_xofs_left + l];
					float p10 = src[y_ofs_up + src_xofs_right + l];
					float p01 = src[y_ofs_down + src_xofs_left + l];
					float p11 = src[y_ofs_down + src_xofs_right + l];

					float interp_up = p00 + (p10 - p00) * xofs_frac;
					float interp_down = p01 + (p11 - p01) * xofs_frac;
					float interp = interp_up + ((interp_down - interp_up) * yofs_frac);

					dst[i * p_dst_width * CC + j * CC + l] = interp;
				}
			}
		}
	}
}

template <int CC, class T>
static void _scale_nearest(const uint8_t *__restrict p_src, uint8_t *__restrict p_dst, uint32_t p_src_width, uint32_t p_src_height, uint32_t p_dst_width, uint32_t p_dst_height) {
	for (uint32_t i = 0; i < p_dst_height; i++) {
		uint32_t src_yofs = i * p_src_height / p_dst_height;
		uint32_t y_ofs = src_yofs * p_src_width * CC;

		for (uint32_t j = 0; j < p_dst_width; j++) {
			uint32_t src_xofs = j * p_src_width / p_dst_width;
			src_xofs *= CC;

			for (uint32_t l = 0; l < CC; l++) {
				const T *src = ((const T *)p_src);
				T *dst = ((T *)p_dst);

				T p = src[y_ofs + src_xofs + l];
				dst[i * p_dst_width * CC + j * CC + l] = p;
			}
		}
	}
}

#define LANCZOS_TYPE 3

static float _lanczos(float p_x) {
	return Math::abs(p_x) >= LANCZOS_TYPE ? 0 : Math::sincn(p_x) * Math::sincn(p_x / LANCZOS_TYPE);
}

template <int CC, class T>
static void _scale_lanczos(const uint8_t *__restrict p_src, uint8_t *__restrict p_dst, uint32_t p_src_width, uint32_t p_src_height, uint32_t p_dst_width, uint32_t p_dst_height) {
	int32_t src_width = p_src_width;
	int32_t src_height = p_src_height;
	int32_t dst_height = p_dst_height;
	int32_t dst_width = p_dst_width;

	uint32_t buffer_size = src_height * dst_width * CC;
	float *buffer = memnew_arr(float, buffer_size); // Store the first pass in a buffer

	{ // FIRST PASS (horizontal)

		float x_scale = float(src_width) / float(dst_width);

		float scale_factor = MAX(x_scale, 1); // A larger kernel is required only when downscaling
		int32_t half_kernel = LANCZOS_TYPE * scale_factor;

		float *kernel = memnew_arr(float, half_kernel * 2);

		for (int32_t buffer_x = 0; buffer_x < dst_width; buffer_x++) {
			// The corresponding point on the source image
			float src_x = (buffer_x + 0.5f) * x_scale; // Offset by 0.5 so it uses the pixel's center
			int32_t start_x = MAX(0, int32_t(src_x) - half_kernel + 1);
			int32_t end_x = MIN(src_width - 1, int32_t(src_x) + half_kernel);

			// Create the kernel used by all the pixels of the column
			for (int32_t target_x = start_x; target_x <= end_x; target_x++) {
				kernel[target_x - start_x] = _lanczos((target_x + 0.5f - src_x) / scale_factor);
			}

			for (int32_t buffer_y = 0; buffer_y < src_height; buffer_y++) {
				float pixel[CC] = { 0 };
				float weight = 0;

				for (int32_t target_x = start_x; target_x <= end_x; target_x++) {
					float lanczos_val = kernel[target_x - start_x];
					weight += lanczos_val;

					const T *__restrict src_data = ((const T *)p_src) + (buffer_y * src_width + target_x) * CC;

					for (uint32_t i = 0; i < CC; i++) {
						if constexpr (sizeof(T) == 2) { //half float
							pixel[i] += Math::half_to_float(src_data[i]) * lanczos_val;
						} else {
							pixel[i] += src_data[i] * lanczos_val;
						}
					}
				}

				float *dst_data = ((float *)buffer) + (buffer_y * dst_width + buffer_x) * CC;

				for (uint32_t i = 0; i < CC; i++) {
					dst_data[i] = pixel[i] / weight; // Normalize the sum of all the samples
				}
			}
		}

		memdelete_arr(kernel);
	} // End of first pass

	{ // SECOND PASS (vertical + result)

		float y_scale = float(src_height) / float(dst_height);

		float scale_factor = MAX(y_scale, 1);
		int32_t half_kernel = LANCZOS_TYPE * scale_factor;

		float *kernel = memnew_arr(float, half_kernel * 2);

		for (int32_t dst_y = 0; dst_y < dst_height; dst_y++) {
			float buffer_y = (dst_y + 0.5f) * y_scale;
			int32_t start_y = MAX(0, int32_t(buffer_y) - half_kernel + 1);
			int32_t end_y = MIN(src_height - 1, int32_t(buffer_y) + half_kernel);

			for (int32_t target_y = start_y; target_y <= end_y; target_y++) {
				kernel[target_y - start_y] = _lanczos((target_y + 0.5f - buffer_y) / scale_factor);
			}

			for (int32_t dst_x = 0; dst_x < dst_width; dst_x++) {
				float pixel[CC] = { 0 };
				float weight = 0;

				for (int32_t target_y = start_y; target_y <= end_y; target_y++) {
					float lanczos_val = kernel[target_y - start_y];
					weight += lanczos_val;

					float *buffer_data = ((float *)buffer) + (target_y * dst_width + dst_x) * CC;

					for (uint32_t i = 0; i < CC; i++) {
						pixel[i] += buffer_data[i] * lanczos_val;
					}
				}

				T *dst_data = ((T *)p_dst) + (dst_y * dst_width + dst_x) * CC;

				for (uint32_t i = 0; i < CC; i++) {
					pixel[i] /= weight;

					if constexpr (sizeof(T) == 1) { //byte
						dst_data[i] = CLAMP(Math::fast_ftoi(pixel[i]), 0, 255);
					} else if constexpr (sizeof(T) == 2) { //half float
						dst_data[i] = Math::make_half_float(pixel[i]);
					} else { // float
						dst_data[i] = pixel[i];
					}
				}
			}
		}

		memdelete_arr(kernel);
	} // End of second pass

	memdelete_arr(buffer);
}

static void _overlay(const uint8_t *__restrict p_src, uint8_t *__restrict p_dst, float p_alpha, uint32_t p_width, uint32_t p_height, uint32_t p_pixel_size) {
	uint16_t alpha = MIN((uint16_t)(p_alpha * 256.0f), 256);

	for (uint32_t i = 0; i < p_width * p_height * p_pixel_size; i++) {
		p_dst[i] = (p_dst[i] * (256 - alpha) + p_src[i] * alpha) >> 8;
	}
}

bool Image::is_size_po2() const {
	return uint32_t(width) == next_power_of_2(width) && uint32_t(height) == next_power_of_2(height);
}

void Image::resize_to_po2(bool p_square, Interpolation p_interpolation) {
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot resize in compressed or custom image formats.");

	int w = next_power_of_2(width);
	int h = next_power_of_2(height);
	if (p_square) {
		w = h = MAX(w, h);
	}

	if (w == width && h == height) {
		if (!p_square || w == h) {
			return; //nothing to do
		}
	}

	resize(w, h, p_interpolation);
}

void Image::resize(int p_width, int p_height, Interpolation p_interpolation) {
	ERR_FAIL_COND_MSG(data.size() == 0, "Cannot resize image before creating it, use set_data() first.");
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot resize in compressed or custom image formats.");

	bool mipmap_aware = p_interpolation == INTERPOLATE_TRILINEAR /* || p_interpolation == INTERPOLATE_TRICUBIC */;

	ERR_FAIL_COND_MSG(p_width <= 0, "Image width must be greater than 0.");
	ERR_FAIL_COND_MSG(p_height <= 0, "Image height must be greater than 0.");
	ERR_FAIL_COND_MSG(p_width > MAX_WIDTH, "Image width cannot be greater than " + itos(MAX_WIDTH) + ".");
	ERR_FAIL_COND_MSG(p_height > MAX_HEIGHT, "Image height cannot be greater than " + itos(MAX_HEIGHT) + ".");
	ERR_FAIL_COND_MSG(p_width * p_height > MAX_PIXELS, "Too many pixels for image, maximum is " + itos(MAX_PIXELS));

	if (p_width == width && p_height == height) {
		return;
	}

	Image dst(p_width, p_height, false, format);

	// Setup mipmap-aware scaling
	Image dst2;
	int mip1 = 0;
	int mip2 = 0;
	float mip1_weight = 0;
	if (mipmap_aware) {
		float avg_scale = ((float)p_width / width + (float)p_height / height) * 0.5f;
		if (avg_scale >= 1.0f) {
			mipmap_aware = false;
		} else {
			float level = Math::log(1.0f / avg_scale) / Math::log(2.0f);
			mip1 = CLAMP((int)Math::floor(level), 0, get_mipmap_count());
			mip2 = CLAMP((int)Math::ceil(level), 0, get_mipmap_count());
			mip1_weight = 1.0f - (level - mip1);
		}
	}
	bool interpolate_mipmaps = mipmap_aware && mip1 != mip2;
	if (interpolate_mipmaps) {
		dst2.initialize_data(p_width, p_height, false, format);
	}

	bool had_mipmaps = mipmaps;
	if (interpolate_mipmaps && !had_mipmaps) {
		generate_mipmaps();
	}
	// --

	const uint8_t *r = data.ptr();
	const unsigned char *r_ptr = r;

	uint8_t *w = dst.data.ptrw();
	unsigned char *w_ptr = w;

	switch (p_interpolation) {
		case INTERPOLATE_NEAREST: {
			if (format >= FORMAT_L8 && format <= FORMAT_RGBA8) {
				switch (get_format_pixel_size(format)) {
					case 1:
						_scale_nearest<1, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 2:
						_scale_nearest<2, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 3:
						_scale_nearest<3, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 4:
						_scale_nearest<4, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}
			} else if (format >= FORMAT_RF && format <= FORMAT_RGBAF) {
				switch (get_format_pixel_size(format)) {
					case 4:
						_scale_nearest<1, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 8:
						_scale_nearest<2, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 12:
						_scale_nearest<3, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 16:
						_scale_nearest<4, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}

			} else if (format >= FORMAT_RH && format <= FORMAT_RGBAH) {
				switch (get_format_pixel_size(format)) {
					case 2:
						_scale_nearest<1, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 4:
						_scale_nearest<2, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 6:
						_scale_nearest<3, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 8:
						_scale_nearest<4, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}
			}

		} break;
		case INTERPOLATE_BILINEAR:
		case INTERPOLATE_TRILINEAR: {
			for (int i = 0; i < 2; ++i) {
				int src_width;
				int src_height;
				const unsigned char *src_ptr;

				if (!mipmap_aware) {
					if (i == 0) {
						// Standard behavior
						src_width = width;
						src_height = height;
						src_ptr = r_ptr;
					} else {
						// No need for a second iteration
						break;
					}
				} else {
					if (i == 0) {
						// Read from the first mipmap that will be interpolated
						// (if both levels are the same, we will not interpolate, but at least we'll sample from the right level)
						int offs;
						_get_mipmap_offset_and_size(mip1, offs, src_width, src_height);
						src_ptr = r_ptr + offs;
					} else if (!interpolate_mipmaps) {
						// No need generate a second image
						break;
					} else {
						// Switch to read from the second mipmap that will be interpolated
						int offs;
						_get_mipmap_offset_and_size(mip2, offs, src_width, src_height);
						src_ptr = r_ptr + offs;
						// Switch to write to the second destination image
						w = dst2.data.ptrw();
						w_ptr = w;
					}
				}

				if (format >= FORMAT_L8 && format <= FORMAT_RGBA8) {
					switch (get_format_pixel_size(format)) {
						case 1:
							_scale_bilinear<1, uint8_t>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 2:
							_scale_bilinear<2, uint8_t>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 3:
							_scale_bilinear<3, uint8_t>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 4:
							_scale_bilinear<4, uint8_t>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
					}
				} else if (format >= FORMAT_RF && format <= FORMAT_RGBAF) {
					switch (get_format_pixel_size(format)) {
						case 4:
							_scale_bilinear<1, float>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 8:
							_scale_bilinear<2, float>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 12:
							_scale_bilinear<3, float>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 16:
							_scale_bilinear<4, float>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
					}
				} else if (format >= FORMAT_RH && format <= FORMAT_RGBAH) {
					switch (get_format_pixel_size(format)) {
						case 2:
							_scale_bilinear<1, uint16_t>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 4:
							_scale_bilinear<2, uint16_t>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 6:
							_scale_bilinear<3, uint16_t>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
						case 8:
							_scale_bilinear<4, uint16_t>(src_ptr, w_ptr, src_width, src_height, p_width, p_height);
							break;
					}
				}
			}

			if (interpolate_mipmaps) {
				// Switch to read again from the first scaled mipmap to overlay it over the second
				r = dst.data.ptr();
				_overlay(r, w, mip1_weight, p_width, p_height, get_format_pixel_size(format));
			}

		} break;
		case INTERPOLATE_CUBIC: {
			if (format >= FORMAT_L8 && format <= FORMAT_RGBA8) {
				switch (get_format_pixel_size(format)) {
					case 1:
						_scale_cubic<1, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 2:
						_scale_cubic<2, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 3:
						_scale_cubic<3, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 4:
						_scale_cubic<4, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}
			} else if (format >= FORMAT_RF && format <= FORMAT_RGBAF) {
				switch (get_format_pixel_size(format)) {
					case 4:
						_scale_cubic<1, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 8:
						_scale_cubic<2, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 12:
						_scale_cubic<3, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 16:
						_scale_cubic<4, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}
			} else if (format >= FORMAT_RH && format <= FORMAT_RGBAH) {
				switch (get_format_pixel_size(format)) {
					case 2:
						_scale_cubic<1, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 4:
						_scale_cubic<2, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 6:
						_scale_cubic<3, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 8:
						_scale_cubic<4, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}
			}
		} break;
		case INTERPOLATE_LANCZOS: {
			if (format >= FORMAT_L8 && format <= FORMAT_RGBA8) {
				switch (get_format_pixel_size(format)) {
					case 1:
						_scale_lanczos<1, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 2:
						_scale_lanczos<2, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 3:
						_scale_lanczos<3, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 4:
						_scale_lanczos<4, uint8_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}
			} else if (format >= FORMAT_RF && format <= FORMAT_RGBAF) {
				switch (get_format_pixel_size(format)) {
					case 4:
						_scale_lanczos<1, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 8:
						_scale_lanczos<2, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 12:
						_scale_lanczos<3, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 16:
						_scale_lanczos<4, float>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}
			} else if (format >= FORMAT_RH && format <= FORMAT_RGBAH) {
				switch (get_format_pixel_size(format)) {
					case 2:
						_scale_lanczos<1, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 4:
						_scale_lanczos<2, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 6:
						_scale_lanczos<3, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
					case 8:
						_scale_lanczos<4, uint16_t>(r_ptr, w_ptr, width, height, p_width, p_height);
						break;
				}
			}
		} break;
	}

	if (interpolate_mipmaps) {
		dst._copy_internals_from(dst2);
	}

	if (had_mipmaps) {
		dst.generate_mipmaps();
	}

	_copy_internals_from(dst);
}

void Image::crop_from_point(int p_x, int p_y, int p_width, int p_height) {
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot crop in compressed or custom image formats.");

	ERR_FAIL_COND_MSG(p_x < 0, "Start x position cannot be smaller than 0.");
	ERR_FAIL_COND_MSG(p_y < 0, "Start y position cannot be smaller than 0.");
	ERR_FAIL_COND_MSG(p_width <= 0, "Width of image must be greater than 0.");
	ERR_FAIL_COND_MSG(p_height <= 0, "Height of image must be greater than 0.");
	ERR_FAIL_COND_MSG(p_x + p_width > MAX_WIDTH, "End x position cannot be greater than " + itos(MAX_WIDTH) + ".");
	ERR_FAIL_COND_MSG(p_y + p_height > MAX_HEIGHT, "End y position cannot be greater than " + itos(MAX_HEIGHT) + ".");

	/* to save memory, cropping should be done in-place, however, since this function
	   will most likely either not be used much, or in critical areas, for now it won't, because
	   it's a waste of time. */

	if (p_width == width && p_height == height && p_x == 0 && p_y == 0) {
		return;
	}

	uint8_t pdata[16]; //largest is 16
	uint32_t pixel_size = get_format_pixel_size(format);

	Image dst(p_width, p_height, false, format);

	{
		const uint8_t *r = data.ptr();
		uint8_t *w = dst.data.ptrw();

		int m_h = p_y + p_height;
		int m_w = p_x + p_width;
		for (int y = p_y; y < m_h; y++) {
			for (int x = p_x; x < m_w; x++) {
				if ((x >= width || y >= height)) {
					for (uint32_t i = 0; i < pixel_size; i++) {
						pdata[i] = 0;
					}
				} else {
					_get_pixelb(x, y, pixel_size, r, pdata);
				}

				dst._put_pixelb(x - p_x, y - p_y, pixel_size, w, pdata);
			}
		}
	}

	if (has_mipmaps()) {
		dst.generate_mipmaps();
	}
	_copy_internals_from(dst);
}

void Image::crop(int p_width, int p_height) {
	crop_from_point(0, 0, p_width, p_height);
}

void Image::rotate_90(ClockDirection p_direction) {
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot rotate in compressed or custom image formats.");
	ERR_FAIL_COND_MSG(width <= 0, "The Image width specified (" + itos(width) + " pixels) must be greater than 0 pixels.");
	ERR_FAIL_COND_MSG(height <= 0, "The Image height specified (" + itos(height) + " pixels) must be greater than 0 pixels.");

	bool used_mipmaps = has_mipmaps();
	if (used_mipmaps) {
		clear_mipmaps();
	}

	// In-place 90 degrees rotation by following the permutation cycles.
	{
		// Explanation by example (clockwise):
		//
		//  abc      da
		//  def  ->  eb
		//           fc
		//
		// In memory:
		//  012345    012345
		//  abcdef -> daebfc
		//
		// Permutation cycles:
		//  (0  --a-->  1  --b-->  3  --d-->  0)
		//  (2  --c-->  5  --f-->  4  --e-->  2)
		//
		// Applying cycles (backwards):
		//  0->s  s=a (store)
		//  3->0  abcdef -> dbcdef
		//  1->3  dbcdef -> dbcbef
		//  s->1  dbcbef -> dacbef
		//
		//  2->s  s=c
		//  4->2  dacbef -> daebef
		//  5->4  daebef -> daebff
		//  s->5  daebff -> daebfc

		const int w = width;
		const int h = height;
		const int size = w * h;

		uint8_t *data_ptr = data.ptrw();
		uint32_t pixel_size = get_format_pixel_size(format);

		uint8_t single_pixel_buffer[16];

#define PREV_INDEX_IN_CYCLE(index) (p_direction == CLOCKWISE) ? ((h - 1 - (index % h)) * w + (index / h)) : ((index % h) * w + (w - 1 - (index / h)))

		if (w == h) { // Square case, 4-length cycles only (plus irrelevant thus skipped 1-length cycle in the middle for odd-sized squares).
			for (int y = 0; y < h / 2; y++) {
				for (int x = 0; x < (w + 1) / 2; x++) {
					int current = y * w + x;
					memcpy(single_pixel_buffer, data_ptr + current * pixel_size, pixel_size);
					for (int i = 0; i < 3; i++) {
						int prev = PREV_INDEX_IN_CYCLE(current);
						memcpy(data_ptr + current * pixel_size, data_ptr + prev * pixel_size, pixel_size);
						current = prev;
					}
					memcpy(data_ptr + current * pixel_size, single_pixel_buffer, pixel_size);
				}
			}
		} else { // Rectangular case (w != h), kinda unpredictable cycles.
			int permuted_pixels_count = 0;

			for (int i = 0; i < size; i++) {
				int prev = PREV_INDEX_IN_CYCLE(i);
				if (prev == i) {
					// 1-length cycle, pixel remains at the same index.
					permuted_pixels_count++;
					continue;
				}

				// Check whether we already processed this cycle.
				// We iterate over it and if we'll find an index smaller than `i` then we already
				// processed this cycle because we always start at the smallest index in the cycle.
				// TODO: Improve this naive approach, can be done better.
				while (prev > i) {
					prev = PREV_INDEX_IN_CYCLE(prev);
				}
				if (prev < i) {
					continue;
				}

				// Save the in-cycle pixel with the smallest index (`i`).
				memcpy(single_pixel_buffer, data_ptr + i * pixel_size, pixel_size);

				// Overwrite pixels one by one by the preceding pixel in the cycle.
				int current = i;
				prev = PREV_INDEX_IN_CYCLE(current);
				while (prev != i) {
					memcpy(data_ptr + current * pixel_size, data_ptr + prev * pixel_size, pixel_size);
					permuted_pixels_count++;

					current = prev;
					prev = PREV_INDEX_IN_CYCLE(current);
				};

				// Overwrite the remaining pixel in the cycle by the saved pixel with the smallest index.
				memcpy(data_ptr + current * pixel_size, single_pixel_buffer, pixel_size);
				permuted_pixels_count++;

				if (permuted_pixels_count == size) {
					break;
				}
			}

			width = h;
			height = w;
		}

#undef PREV_INDEX_IN_CYCLE
	}

	if (used_mipmaps) {
		generate_mipmaps();
	}
}

void Image::rotate_180() {
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot rotate in compressed or custom image formats.");
	ERR_FAIL_COND_MSG(width <= 0, "The Image width specified (" + itos(width) + " pixels) must be greater than 0 pixels.");
	ERR_FAIL_COND_MSG(height <= 0, "The Image height specified (" + itos(height) + " pixels) must be greater than 0 pixels.");

	bool used_mipmaps = has_mipmaps();
	if (used_mipmaps) {
		clear_mipmaps();
	}

	{
		uint8_t *data_ptr = data.ptrw();
		uint32_t pixel_size = get_format_pixel_size(format);

		uint8_t single_pixel_buffer[16];

		uint8_t *from_begin_ptr = data_ptr;
		uint8_t *from_end_ptr = data_ptr + (width * height - 1) * pixel_size;

		while (from_begin_ptr < from_end_ptr) {
			memcpy(single_pixel_buffer, from_begin_ptr, pixel_size);
			memcpy(from_begin_ptr, from_end_ptr, pixel_size);
			memcpy(from_end_ptr, single_pixel_buffer, pixel_size);

			from_begin_ptr += pixel_size;
			from_end_ptr -= pixel_size;
		}
	}

	if (used_mipmaps) {
		generate_mipmaps();
	}
}

void Image::flip_y() {
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot flip_y in compressed or custom image formats.");

	bool used_mipmaps = has_mipmaps();
	if (used_mipmaps) {
		clear_mipmaps();
	}

	{
		uint8_t *w = data.ptrw();
		uint8_t up[16];
		uint8_t down[16];
		uint32_t pixel_size = get_format_pixel_size(format);

		for (int y = 0; y < height / 2; y++) {
			for (int x = 0; x < width; x++) {
				_get_pixelb(x, y, pixel_size, w, up);
				_get_pixelb(x, height - y - 1, pixel_size, w, down);

				_put_pixelb(x, height - y - 1, pixel_size, w, up);
				_put_pixelb(x, y, pixel_size, w, down);
			}
		}
	}

	if (used_mipmaps) {
		generate_mipmaps();
	}
}

void Image::flip_x() {
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot flip_x in compressed or custom image formats.");

	bool used_mipmaps = has_mipmaps();
	if (used_mipmaps) {
		clear_mipmaps();
	}

	{
		uint8_t *w = data.ptrw();
		uint8_t up[16];
		uint8_t down[16];
		uint32_t pixel_size = get_format_pixel_size(format);

		for (int y = 0; y < height; y++) {
			for (int x = 0; x < width / 2; x++) {
				_get_pixelb(x, y, pixel_size, w, up);
				_get_pixelb(width - x - 1, y, pixel_size, w, down);

				_put_pixelb(width - x - 1, y, pixel_size, w, up);
				_put_pixelb(x, y, pixel_size, w, down);
			}
		}
	}

	if (used_mipmaps) {
		generate_mipmaps();
	}
}

/// Get mipmap size and offset.
int Image::_get_dst_image_size(int p_width, int p_height, Format p_format, int &r_mipmaps, int p_mipmaps, int *r_mm_width, int *r_mm_height) {
	// Data offset in mipmaps (including the original texture).
	int size = 0;

	int w = p_width;
	int h = p_height;

	// Current mipmap index in the loop below. p_mipmaps is the target mipmap index.
	// In this function, mipmap 0 represents the first mipmap instead of the original texture.
	int mm = 0;

	int pixsize = get_format_pixel_size(p_format);
	int pixshift = get_format_pixel_rshift(p_format);
	int block = get_format_block_size(p_format);

	// Technically, you can still compress up to 1 px no matter the format, so commenting this.
	//int minw, minh;
	//get_format_min_pixel_size(p_format, minw, minh);
	int minw = 1, minh = 1;

	while (true) {
		int bw = w % block != 0 ? w + (block - w % block) : w;
		int bh = h % block != 0 ? h + (block - h % block) : h;

		int s = bw * bh;

		s *= pixsize;
		s >>= pixshift;

		size += s;

		if (p_mipmaps >= 0) {
			w = MAX(minw, w >> 1);
			h = MAX(minh, h >> 1);
		} else {
			if (w == minw && h == minh) {
				break;
			}
			w = MAX(minw, w >> 1);
			h = MAX(minh, h >> 1);
		}

		// Set mipmap size.
		if (r_mm_width) {
			*r_mm_width = w;
		}
		if (r_mm_height) {
			*r_mm_height = h;
		}

		// Reach target mipmap.
		if (p_mipmaps >= 0 && mm == p_mipmaps) {
			break;
		}

		mm++;
	}

	r_mipmaps = mm;
	return size;
}

bool Image::_can_modify(Format p_format) const {
	return p_format <= FORMAT_RGBE9995;
}

template <class Component, int CC, bool renormalize,
		void (*average_func)(Component &, const Component &, const Component &, const Component &, const Component &),
		void (*renormalize_func)(Component *)>
static void _generate_po2_mipmap(const Component *p_src, Component *p_dst, uint32_t p_width, uint32_t p_height) {
	//fast power of 2 mipmap generation
	uint32_t dst_w = MAX(p_width >> 1, 1u);
	uint32_t dst_h = MAX(p_height >> 1, 1u);

	int right_step = (p_width == 1) ? 0 : CC;
	int down_step = (p_height == 1) ? 0 : (p_width * CC);

	for (uint32_t i = 0; i < dst_h; i++) {
		const Component *rup_ptr = &p_src[i * 2 * down_step];
		const Component *rdown_ptr = rup_ptr + down_step;
		Component *dst_ptr = &p_dst[i * dst_w * CC];
		uint32_t count = dst_w;

		while (count) {
			count--;
			for (int j = 0; j < CC; j++) {
				average_func(dst_ptr[j], rup_ptr[j], rup_ptr[j + right_step], rdown_ptr[j], rdown_ptr[j + right_step]);
			}

			if (renormalize) {
				renormalize_func(dst_ptr);
			}

			dst_ptr += CC;
			rup_ptr += right_step * 2;
			rdown_ptr += right_step * 2;
		}
	}
}

void Image::shrink_x2() {
	ERR_FAIL_COND(data.size() == 0);

	if (mipmaps) {
		//just use the lower mipmap as base and copy all
		Vector<uint8_t> new_img;

		int ofs = get_mipmap_offset(1);

		int new_size = data.size() - ofs;
		new_img.resize(new_size);
		ERR_FAIL_COND(new_img.size() == 0);

		{
			uint8_t *w = new_img.ptrw();
			const uint8_t *r = data.ptr();

			memcpy(w, &r[ofs], new_size);
		}

		width = MAX(width / 2, 1);
		height = MAX(height / 2, 1);
		data = new_img;

	} else {
		Vector<uint8_t> new_img;

		ERR_FAIL_COND(!_can_modify(format));
		int ps = get_format_pixel_size(format);
		new_img.resize((width / 2) * (height / 2) * ps);
		ERR_FAIL_COND(new_img.size() == 0);
		ERR_FAIL_COND(data.size() == 0);

		{
			uint8_t *w = new_img.ptrw();
			const uint8_t *r = data.ptr();

			switch (format) {
				case FORMAT_L8:
				case FORMAT_R8:
					_generate_po2_mipmap<uint8_t, 1, false, Image::average_4_uint8, Image::renormalize_uint8>(r, w, width, height);
					break;
				case FORMAT_LA8:
					_generate_po2_mipmap<uint8_t, 2, false, Image::average_4_uint8, Image::renormalize_uint8>(r, w, width, height);
					break;
				case FORMAT_RG8:
					_generate_po2_mipmap<uint8_t, 2, false, Image::average_4_uint8, Image::renormalize_uint8>(r, w, width, height);
					break;
				case FORMAT_RGB8:
					_generate_po2_mipmap<uint8_t, 3, false, Image::average_4_uint8, Image::renormalize_uint8>(r, w, width, height);
					break;
				case FORMAT_RGBA8:
					_generate_po2_mipmap<uint8_t, 4, false, Image::average_4_uint8, Image::renormalize_uint8>(r, w, width, height);
					break;

				case FORMAT_RF:
					_generate_po2_mipmap<float, 1, false, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(r), reinterpret_cast<float *>(w), width, height);
					break;
				case FORMAT_RGF:
					_generate_po2_mipmap<float, 2, false, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(r), reinterpret_cast<float *>(w), width, height);
					break;
				case FORMAT_RGBF:
					_generate_po2_mipmap<float, 3, false, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(r), reinterpret_cast<float *>(w), width, height);
					break;
				case FORMAT_RGBAF:
					_generate_po2_mipmap<float, 4, false, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(r), reinterpret_cast<float *>(w), width, height);
					break;

				case FORMAT_RH:
					_generate_po2_mipmap<uint16_t, 1, false, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(r), reinterpret_cast<uint16_t *>(w), width, height);
					break;
				case FORMAT_RGH:
					_generate_po2_mipmap<uint16_t, 2, false, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(r), reinterpret_cast<uint16_t *>(w), width, height);
					break;
				case FORMAT_RGBH:
					_generate_po2_mipmap<uint16_t, 3, false, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(r), reinterpret_cast<uint16_t *>(w), width, height);
					break;
				case FORMAT_RGBAH:
					_generate_po2_mipmap<uint16_t, 4, false, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(r), reinterpret_cast<uint16_t *>(w), width, height);
					break;

				case FORMAT_RGBE9995:
					_generate_po2_mipmap<uint32_t, 1, false, Image::average_4_rgbe9995, Image::renormalize_rgbe9995>(reinterpret_cast<const uint32_t *>(r), reinterpret_cast<uint32_t *>(w), width, height);
					break;
				default: {
				}
			}
		}

		width /= 2;
		height /= 2;
		data = new_img;
	}
}

void Image::normalize() {
	bool used_mipmaps = has_mipmaps();
	if (used_mipmaps) {
		clear_mipmaps();
	}

	for (int y = 0; y < height; y++) {
		for (int x = 0; x < width; x++) {
			Color c = get_pixel(x, y);
			Vector3 v(c.r * 2.0 - 1.0, c.g * 2.0 - 1.0, c.b * 2.0 - 1.0);
			v.normalize();
			c.r = v.x * 0.5 + 0.5;
			c.g = v.y * 0.5 + 0.5;
			c.b = v.z * 0.5 + 0.5;
			set_pixel(x, y, c);
		}
	}

	if (used_mipmaps) {
		generate_mipmaps(true);
	}
}

Error Image::generate_mipmaps(bool p_renormalize) {
	ERR_FAIL_COND_V_MSG(!_can_modify(format), ERR_UNAVAILABLE, "Cannot generate mipmaps in compressed or custom image formats.");

	ERR_FAIL_COND_V_MSG(format == FORMAT_RGBA4444, ERR_UNAVAILABLE, "Cannot generate mipmaps from RGBA4444 format.");

	ERR_FAIL_COND_V_MSG(width == 0 || height == 0, ERR_UNCONFIGURED, "Cannot generate mipmaps with width or height equal to 0.");

	int mmcount;

	int size = _get_dst_image_size(width, height, format, mmcount);

	data.resize(size);

	uint8_t *wp = data.ptrw();

	int prev_ofs = 0;
	int prev_h = height;
	int prev_w = width;

	for (int i = 1; i <= mmcount; i++) {
		int ofs, w, h;
		_get_mipmap_offset_and_size(i, ofs, w, h);

		switch (format) {
			case FORMAT_L8:
			case FORMAT_R8:
				_generate_po2_mipmap<uint8_t, 1, false, Image::average_4_uint8, Image::renormalize_uint8>(&wp[prev_ofs], &wp[ofs], prev_w, prev_h);
				break;
			case FORMAT_LA8:
			case FORMAT_RG8:
				_generate_po2_mipmap<uint8_t, 2, false, Image::average_4_uint8, Image::renormalize_uint8>(&wp[prev_ofs], &wp[ofs], prev_w, prev_h);
				break;
			case FORMAT_RGB8:
				if (p_renormalize) {
					_generate_po2_mipmap<uint8_t, 3, true, Image::average_4_uint8, Image::renormalize_uint8>(&wp[prev_ofs], &wp[ofs], prev_w, prev_h);
				} else {
					_generate_po2_mipmap<uint8_t, 3, false, Image::average_4_uint8, Image::renormalize_uint8>(&wp[prev_ofs], &wp[ofs], prev_w, prev_h);
				}

				break;
			case FORMAT_RGBA8:
				if (p_renormalize) {
					_generate_po2_mipmap<uint8_t, 4, true, Image::average_4_uint8, Image::renormalize_uint8>(&wp[prev_ofs], &wp[ofs], prev_w, prev_h);
				} else {
					_generate_po2_mipmap<uint8_t, 4, false, Image::average_4_uint8, Image::renormalize_uint8>(&wp[prev_ofs], &wp[ofs], prev_w, prev_h);
				}
				break;
			case FORMAT_RF:
				_generate_po2_mipmap<float, 1, false, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(&wp[prev_ofs]), reinterpret_cast<float *>(&wp[ofs]), prev_w, prev_h);
				break;
			case FORMAT_RGF:
				_generate_po2_mipmap<float, 2, false, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(&wp[prev_ofs]), reinterpret_cast<float *>(&wp[ofs]), prev_w, prev_h);
				break;
			case FORMAT_RGBF:
				if (p_renormalize) {
					_generate_po2_mipmap<float, 3, true, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(&wp[prev_ofs]), reinterpret_cast<float *>(&wp[ofs]), prev_w, prev_h);
				} else {
					_generate_po2_mipmap<float, 3, false, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(&wp[prev_ofs]), reinterpret_cast<float *>(&wp[ofs]), prev_w, prev_h);
				}

				break;
			case FORMAT_RGBAF:
				if (p_renormalize) {
					_generate_po2_mipmap<float, 4, true, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(&wp[prev_ofs]), reinterpret_cast<float *>(&wp[ofs]), prev_w, prev_h);
				} else {
					_generate_po2_mipmap<float, 4, false, Image::average_4_float, Image::renormalize_float>(reinterpret_cast<const float *>(&wp[prev_ofs]), reinterpret_cast<float *>(&wp[ofs]), prev_w, prev_h);
				}

				break;
			case FORMAT_RH:
				_generate_po2_mipmap<uint16_t, 1, false, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(&wp[prev_ofs]), reinterpret_cast<uint16_t *>(&wp[ofs]), prev_w, prev_h);
				break;
			case FORMAT_RGH:
				_generate_po2_mipmap<uint16_t, 2, false, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(&wp[prev_ofs]), reinterpret_cast<uint16_t *>(&wp[ofs]), prev_w, prev_h);
				break;
			case FORMAT_RGBH:
				if (p_renormalize) {
					_generate_po2_mipmap<uint16_t, 3, true, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(&wp[prev_ofs]), reinterpret_cast<uint16_t *>(&wp[ofs]), prev_w, prev_h);
				} else {
					_generate_po2_mipmap<uint16_t, 3, false, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(&wp[prev_ofs]), reinterpret_cast<uint16_t *>(&wp[ofs]), prev_w, prev_h);
				}

				break;
			case FORMAT_RGBAH:
				if (p_renormalize) {
					_generate_po2_mipmap<uint16_t, 4, true, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(&wp[prev_ofs]), reinterpret_cast<uint16_t *>(&wp[ofs]), prev_w, prev_h);
				} else {
					_generate_po2_mipmap<uint16_t, 4, false, Image::average_4_half, Image::renormalize_half>(reinterpret_cast<const uint16_t *>(&wp[prev_ofs]), reinterpret_cast<uint16_t *>(&wp[ofs]), prev_w, prev_h);
				}

				break;
			case FORMAT_RGBE9995:
				if (p_renormalize) {
					_generate_po2_mipmap<uint32_t, 1, true, Image::average_4_rgbe9995, Image::renormalize_rgbe9995>(reinterpret_cast<const uint32_t *>(&wp[prev_ofs]), reinterpret_cast<uint32_t *>(&wp[ofs]), prev_w, prev_h);
				} else {
					_generate_po2_mipmap<uint32_t, 1, false, Image::average_4_rgbe9995, Image::renormalize_rgbe9995>(reinterpret_cast<const uint32_t *>(&wp[prev_ofs]), reinterpret_cast<uint32_t *>(&wp[ofs]), prev_w, prev_h);
				}

				break;
			default: {
			}
		}

		prev_ofs = ofs;
		prev_w = w;
		prev_h = h;
	}

	mipmaps = true;

	return OK;
}

Error Image::generate_mipmap_roughness(RoughnessChannel p_roughness_channel, const Ref<Image> &p_normal_map) {
	Vector<double> normal_sat_vec; //summed area table
	double *normal_sat = nullptr; //summed area table for normal map
	int normal_w = 0, normal_h = 0;

	ERR_FAIL_COND_V_MSG(p_normal_map.is_null() || p_normal_map->is_empty(), ERR_INVALID_PARAMETER, "Must provide a valid normal map for roughness mipmaps");

	Ref<Image> nm = p_normal_map->duplicate();
	if (nm->is_compressed()) {
		nm->decompress();
	}

	normal_w = nm->get_width();
	normal_h = nm->get_height();

	normal_sat_vec.resize(normal_w * normal_h * 3);

	normal_sat = normal_sat_vec.ptrw();

	//create summed area table

	for (int y = 0; y < normal_h; y++) {
		double line_sum[3] = { 0, 0, 0 };
		for (int x = 0; x < normal_w; x++) {
			double normal[3];
			Color color = nm->get_pixel(x, y);
			normal[0] = color.r * 2.0 - 1.0;
			normal[1] = color.g * 2.0 - 1.0;
			normal[2] = Math::sqrt(MAX(0.0, 1.0 - (normal[0] * normal[0] + normal[1] * normal[1]))); //reconstruct if missing

			line_sum[0] += normal[0];
			line_sum[1] += normal[1];
			line_sum[2] += normal[2];

			uint32_t ofs = (y * normal_w + x) * 3;

			normal_sat[ofs + 0] = line_sum[0];
			normal_sat[ofs + 1] = line_sum[1];
			normal_sat[ofs + 2] = line_sum[2];

			if (y > 0) {
				uint32_t prev_ofs = ((y - 1) * normal_w + x) * 3;
				normal_sat[ofs + 0] += normal_sat[prev_ofs + 0];
				normal_sat[ofs + 1] += normal_sat[prev_ofs + 1];
				normal_sat[ofs + 2] += normal_sat[prev_ofs + 2];
			}
		}
	}

#if 0
	{
		Vector3 beg(normal_sat_vec[0], normal_sat_vec[1], normal_sat_vec[2]);
		Vector3 end(normal_sat_vec[normal_sat_vec.size() - 3], normal_sat_vec[normal_sat_vec.size() - 2], normal_sat_vec[normal_sat_vec.size() - 1]);
		Vector3 avg = (end - beg) / (normal_w * normal_h);
		print_line("average: " + avg);
	}
#endif

	int mmcount;

	_get_dst_image_size(width, height, format, mmcount);

	uint8_t *base_ptr = data.ptrw();

	for (int i = 1; i <= mmcount; i++) {
		int ofs, w, h;
		_get_mipmap_offset_and_size(i, ofs, w, h);
		uint8_t *ptr = &base_ptr[ofs];

		for (int x = 0; x < w; x++) {
			for (int y = 0; y < h; y++) {
				int from_x = x * normal_w / w;
				int from_y = y * normal_h / h;
				int to_x = (x + 1) * normal_w / w;
				int to_y = (y + 1) * normal_h / h;
				to_x = MIN(to_x - 1, normal_w);
				to_y = MIN(to_y - 1, normal_h);

				int size_x = (to_x - from_x) + 1;
				int size_y = (to_y - from_y) + 1;

				//summed area table version (much faster)

				double avg[3] = { 0, 0, 0 };

				if (from_x > 0 && from_y > 0) {
					uint32_t tofs = ((from_y - 1) * normal_w + (from_x - 1)) * 3;
					avg[0] += normal_sat[tofs + 0];
					avg[1] += normal_sat[tofs + 1];
					avg[2] += normal_sat[tofs + 2];
				}

				if (from_y > 0) {
					uint32_t tofs = ((from_y - 1) * normal_w + to_x) * 3;
					avg[0] -= normal_sat[tofs + 0];
					avg[1] -= normal_sat[tofs + 1];
					avg[2] -= normal_sat[tofs + 2];
				}

				if (from_x > 0) {
					uint32_t tofs = (to_y * normal_w + (from_x - 1)) * 3;
					avg[0] -= normal_sat[tofs + 0];
					avg[1] -= normal_sat[tofs + 1];
					avg[2] -= normal_sat[tofs + 2];
				}

				uint32_t tofs = (to_y * normal_w + to_x) * 3;
				avg[0] += normal_sat[tofs + 0];
				avg[1] += normal_sat[tofs + 1];
				avg[2] += normal_sat[tofs + 2];

				double div = double(size_x * size_y);
				Vector3 vec(avg[0] / div, avg[1] / div, avg[2] / div);

				float r = vec.length();

				int pixel_ofs = y * w + x;
				Color c = _get_color_at_ofs(ptr, pixel_ofs);

				float roughness = 0;

				switch (p_roughness_channel) {
					case ROUGHNESS_CHANNEL_R: {
						roughness = c.r;
					} break;
					case ROUGHNESS_CHANNEL_G: {
						roughness = c.g;
					} break;
					case ROUGHNESS_CHANNEL_B: {
						roughness = c.b;
					} break;
					case ROUGHNESS_CHANNEL_L: {
						roughness = c.get_v();
					} break;
					case ROUGHNESS_CHANNEL_A: {
						roughness = c.a;
					} break;
				}

				float variance = 0;
				if (r < 1.0f) {
					float r2 = r * r;
					float kappa = (3.0f * r - r * r2) / (1.0f - r2);
					variance = 0.25f / kappa;
				}

				float threshold = 0.4;
				roughness = Math::sqrt(roughness * roughness + MIN(3.0f * variance, threshold * threshold));

				switch (p_roughness_channel) {
					case ROUGHNESS_CHANNEL_R: {
						c.r = roughness;
					} break;
					case ROUGHNESS_CHANNEL_G: {
						c.g = roughness;
					} break;
					case ROUGHNESS_CHANNEL_B: {
						c.b = roughness;
					} break;
					case ROUGHNESS_CHANNEL_L: {
						c.r = roughness;
						c.g = roughness;
						c.b = roughness;
					} break;
					case ROUGHNESS_CHANNEL_A: {
						c.a = roughness;
					} break;
				}

				_set_color_at_ofs(ptr, pixel_ofs, c);
			}
		}
#if 0
		{
			int size = get_mipmap_byte_size(i);
			print_line("size for mimpap " + itos(i) + ": " + itos(size));
			Vector<uint8_t> imgdata;
			imgdata.resize(size);


			uint8_t* wr = imgdata.ptrw();
			memcpy(wr.ptr(), ptr, size);
			wr = uint8_t*();
			Ref<Image> im = Image::create_from_data(w, h, false, format, imgdata);
			im->save_png("res://mipmap_" + itos(i) + ".png");
		}
#endif
	}

	return OK;
}

void Image::clear_mipmaps() {
	if (!mipmaps) {
		return;
	}

	if (is_empty()) {
		return;
	}

	int ofs, w, h;
	_get_mipmap_offset_and_size(1, ofs, w, h);
	data.resize(ofs);

	mipmaps = false;
}

bool Image::is_empty() const {
	return (data.size() == 0);
}

Vector<uint8_t> Image::get_data() const {
	return data;
}

Ref<Image> Image::create_empty(int p_width, int p_height, bool p_use_mipmaps, Format p_format) {
	Ref<Image> image;
	image.instantiate();
	image->initialize_data(p_width, p_height, p_use_mipmaps, p_format);
	return image;
}

Ref<Image> Image::create_from_data(int p_width, int p_height, bool p_use_mipmaps, Format p_format, const Vector<uint8_t> &p_data) {
	Ref<Image> image;
	image.instantiate();
	image->initialize_data(p_width, p_height, p_use_mipmaps, p_format, p_data);
	return image;
}

void Image::set_data(int p_width, int p_height, bool p_use_mipmaps, Format p_format, const Vector<uint8_t> &p_data) {
	initialize_data(p_width, p_height, p_use_mipmaps, p_format, p_data);
}

void Image::initialize_data(int p_width, int p_height, bool p_use_mipmaps, Format p_format) {
	ERR_FAIL_COND_MSG(p_width <= 0, "The Image width specified (" + itos(p_width) + " pixels) must be greater than 0 pixels.");
	ERR_FAIL_COND_MSG(p_height <= 0, "The Image height specified (" + itos(p_height) + " pixels) must be greater than 0 pixels.");
	ERR_FAIL_COND_MSG(p_width > MAX_WIDTH,
			"The Image width specified (" + itos(p_width) + " pixels) cannot be greater than " + itos(MAX_WIDTH) + "pixels.");
	ERR_FAIL_COND_MSG(p_height > MAX_HEIGHT,
			"The Image height specified (" + itos(p_height) + " pixels) cannot be greater than " + itos(MAX_HEIGHT) + "pixels.");
	ERR_FAIL_COND_MSG(p_width * p_height > MAX_PIXELS,
			"Too many pixels for Image. Maximum is " + itos(MAX_WIDTH) + "x" + itos(MAX_HEIGHT) + " = " + itos(MAX_PIXELS) + "pixels.");
	ERR_FAIL_INDEX_MSG(p_format, FORMAT_MAX, "The Image format specified (" + itos(p_format) + ") is out of range. See Image's Format enum.");

	int mm = 0;
	int size = _get_dst_image_size(p_width, p_height, p_format, mm, p_use_mipmaps ? -1 : 0);
	data.resize(size);

	{
		uint8_t *w = data.ptrw();
		memset(w, 0, size);
	}

	width = p_width;
	height = p_height;
	mipmaps = p_use_mipmaps;
	format = p_format;
}

void Image::initialize_data(int p_width, int p_height, bool p_use_mipmaps, Format p_format, const Vector<uint8_t> &p_data) {
	ERR_FAIL_COND_MSG(p_width <= 0, "The Image width specified (" + itos(p_width) + " pixels) must be greater than 0 pixels.");
	ERR_FAIL_COND_MSG(p_height <= 0, "The Image height specified (" + itos(p_height) + " pixels) must be greater than 0 pixels.");
	ERR_FAIL_COND_MSG(p_width > MAX_WIDTH,
			"The Image width specified (" + itos(p_width) + " pixels) cannot be greater than " + itos(MAX_WIDTH) + " pixels.");
	ERR_FAIL_COND_MSG(p_height > MAX_HEIGHT,
			"The Image height specified (" + itos(p_height) + " pixels) cannot be greater than " + itos(MAX_HEIGHT) + " pixels.");
	ERR_FAIL_COND_MSG(p_width * p_height > MAX_PIXELS,
			"Too many pixels for Image. Maximum is " + itos(MAX_WIDTH) + "x" + itos(MAX_HEIGHT) + " = " + itos(MAX_PIXELS) + "pixels .");
	ERR_FAIL_INDEX_MSG(p_format, FORMAT_MAX, "The Image format specified (" + itos(p_format) + ") is out of range. See Image's Format enum.");

	int mm;
	int size = _get_dst_image_size(p_width, p_height, p_format, mm, p_use_mipmaps ? -1 : 0);

	if (unlikely(p_data.size() != size)) {
		String description_mipmaps = get_format_name(p_format) + " ";
		if (p_use_mipmaps) {
			const int num_mipmaps = get_image_required_mipmaps(p_width, p_height, p_format);
			if (num_mipmaps != 1) {
				description_mipmaps += vformat("with %d mipmaps", num_mipmaps);
			} else {
				description_mipmaps += "with 1 mipmap";
			}
		} else {
			description_mipmaps += "without mipmaps";
		}
		const String description = vformat("%dx%dx%d (%s)", p_width, p_height, get_format_pixel_size(p_format), description_mipmaps);
		ERR_FAIL_MSG(vformat("Expected Image data size of %s = %d bytes, got %d bytes instead.", description, size, p_data.size()));
	}

	height = p_height;
	width = p_width;
	format = p_format;
	data = p_data;

	mipmaps = p_use_mipmaps;
}

void Image::initialize_data(const char **p_xpm) {
	int size_width = 0;
	int size_height = 0;
	int pixelchars = 0;
	mipmaps = false;
	bool has_alpha = false;

	enum Status {
		READING_HEADER,
		READING_COLORS,
		READING_PIXELS,
		DONE
	};

	Status status = READING_HEADER;
	int line = 0;

	HashMap<String, Color> colormap;
	int colormap_size = 0;
	uint32_t pixel_size = 0;
	uint8_t *data_write = nullptr;

	while (status != DONE) {
		const char *line_ptr = p_xpm[line];

		switch (status) {
			case READING_HEADER: {
				String line_str = line_ptr;
				line_str.replace("\t", " ");

				size_width = line_str.get_slicec(' ', 0).to_int();
				size_height = line_str.get_slicec(' ', 1).to_int();
				colormap_size = line_str.get_slicec(' ', 2).to_int();
				pixelchars = line_str.get_slicec(' ', 3).to_int();
				ERR_FAIL_COND(colormap_size > 32766);
				ERR_FAIL_COND(pixelchars > 5);
				ERR_FAIL_COND(size_width > 32767);
				ERR_FAIL_COND(size_height > 32767);
				status = READING_COLORS;
			} break;
			case READING_COLORS: {
				String colorstring;
				for (int i = 0; i < pixelchars; i++) {
					colorstring += *line_ptr;
					line_ptr++;
				}
				//skip spaces
				while (*line_ptr == ' ' || *line_ptr == '\t' || *line_ptr == 0) {
					if (*line_ptr == 0) {
						break;
					}
					line_ptr++;
				}
				if (*line_ptr == 'c') {
					line_ptr++;
					while (*line_ptr == ' ' || *line_ptr == '\t' || *line_ptr == 0) {
						if (*line_ptr == 0) {
							break;
						}
						line_ptr++;
					}

					if (*line_ptr == '#') {
						line_ptr++;
						uint8_t col_r = 0;
						uint8_t col_g = 0;
						uint8_t col_b = 0;
						//uint8_t col_a=255;

						for (int i = 0; i < 6; i++) {
							char v = line_ptr[i];

							if (is_digit(v)) {
								v -= '0';
							} else if (v >= 'A' && v <= 'F') {
								v = (v - 'A') + 10;
							} else if (v >= 'a' && v <= 'f') {
								v = (v - 'a') + 10;
							} else {
								break;
							}

							switch (i) {
								case 0:
									col_r = v << 4;
									break;
								case 1:
									col_r |= v;
									break;
								case 2:
									col_g = v << 4;
									break;
								case 3:
									col_g |= v;
									break;
								case 4:
									col_b = v << 4;
									break;
								case 5:
									col_b |= v;
									break;
							}
						}

						// magenta mask
						if (col_r == 255 && col_g == 0 && col_b == 255) {
							colormap[colorstring] = Color(0, 0, 0, 0);
							has_alpha = true;
						} else {
							colormap[colorstring] = Color(col_r / 255.0, col_g / 255.0, col_b / 255.0, 1.0);
						}
					}
				}
				if (line == colormap_size) {
					status = READING_PIXELS;
					initialize_data(size_width, size_height, false, has_alpha ? FORMAT_RGBA8 : FORMAT_RGB8);
					data_write = data.ptrw();
					pixel_size = has_alpha ? 4 : 3;
				}
			} break;
			case READING_PIXELS: {
				int y = line - colormap_size - 1;
				for (int x = 0; x < size_width; x++) {
					char pixelstr[6] = { 0, 0, 0, 0, 0, 0 };
					for (int i = 0; i < pixelchars; i++) {
						pixelstr[i] = line_ptr[x * pixelchars + i];
					}

					Color *colorptr = colormap.getptr(pixelstr);
					ERR_FAIL_COND(!colorptr);
					uint8_t pixel[4];
					for (uint32_t i = 0; i < pixel_size; i++) {
						pixel[i] = CLAMP((*colorptr)[i] * 255, 0, 255);
					}
					_put_pixelb(x, y, pixel_size, data_write, pixel);
				}

				if (y == (size_height - 1)) {
					status = DONE;
				}
			} break;
			default: {
			}
		}

		line++;
	}
}
#define DETECT_ALPHA_MAX_THRESHOLD 254
#define DETECT_ALPHA_MIN_THRESHOLD 2

#define DETECT_ALPHA(m_value)                          \
	{                                                  \
		uint8_t value = m_value;                       \
		if (value < DETECT_ALPHA_MIN_THRESHOLD)        \
			bit = true;                                \
		else if (value < DETECT_ALPHA_MAX_THRESHOLD) { \
			detected = true;                           \
			break;                                     \
		}                                              \
	}

#define DETECT_NON_ALPHA(m_value) \
	{                             \
		uint8_t value = m_value;  \
		if (value > 0) {          \
			detected = true;      \
			break;                \
		}                         \
	}

bool Image::is_invisible() const {
	if (format == FORMAT_L8 ||
			format == FORMAT_RGB8 || format == FORMAT_RG8) {
		return false;
	}

	int len = data.size();

	if (len == 0) {
		return true;
	}

	int w, h;
	_get_mipmap_offset_and_size(1, len, w, h);

	const uint8_t *r = data.ptr();
	const unsigned char *data_ptr = r;

	bool detected = false;

	switch (format) {
		case FORMAT_LA8: {
			for (int i = 0; i < (len >> 1); i++) {
				DETECT_NON_ALPHA(data_ptr[(i << 1) + 1]);
			}

		} break;
		case FORMAT_RGBA8: {
			for (int i = 0; i < (len >> 2); i++) {
				DETECT_NON_ALPHA(data_ptr[(i << 2) + 3])
			}

		} break;

		case FORMAT_DXT3:
		case FORMAT_DXT5: {
			detected = true;
		} break;
		default: {
		}
	}

	return !detected;
}

Image::AlphaMode Image::detect_alpha() const {
	int len = data.size();

	if (len == 0) {
		return ALPHA_NONE;
	}

	int w, h;
	_get_mipmap_offset_and_size(1, len, w, h);

	const uint8_t *r = data.ptr();
	const unsigned char *data_ptr = r;

	bool bit = false;
	bool detected = false;

	switch (format) {
		case FORMAT_LA8: {
			for (int i = 0; i < (len >> 1); i++) {
				DETECT_ALPHA(data_ptr[(i << 1) + 1]);
			}

		} break;
		case FORMAT_RGBA8: {
			for (int i = 0; i < (len >> 2); i++) {
				DETECT_ALPHA(data_ptr[(i << 2) + 3])
			}

		} break;
		case FORMAT_DXT3:
		case FORMAT_DXT5: {
			detected = true;
		} break;
		default: {
		}
	}

	if (detected) {
		return ALPHA_BLEND;
	} else if (bit) {
		return ALPHA_BIT;
	} else {
		return ALPHA_NONE;
	}
}

Error Image::load(const String &p_path) {
#ifdef DEBUG_ENABLED
	if (p_path.begins_with("res://") && ResourceLoader::exists(p_path)) {
		WARN_PRINT("Loaded resource as image file, this will not work on export: '" + p_path + "'. Instead, import the image file as an Image resource and load it normally as a resource.");
	}
#endif
	return ImageLoader::load_image(p_path, this);
}

Ref<Image> Image::load_from_file(const String &p_path) {
#ifdef DEBUG_ENABLED
	if (p_path.begins_with("res://") && ResourceLoader::exists(p_path)) {
		WARN_PRINT("Loaded resource as image file, this will not work on export: '" + p_path + "'. Instead, import the image file as an Image resource and load it normally as a resource.");
	}
#endif
	Ref<Image> image;
	image.instantiate();
	Error err = ImageLoader::load_image(p_path, image);
	if (err != OK) {
		ERR_FAIL_V_MSG(Ref<Image>(), vformat("Failed to load image. Error %d", err));
	}
	return image;
}

Error Image::save_png(const String &p_path) const {
	if (save_png_func == nullptr) {
		return ERR_UNAVAILABLE;
	}

	return save_png_func(p_path, Ref<Image>((Image *)this));
}

Error Image::save_jpg(const String &p_path, float p_quality) const {
	if (save_jpg_func == nullptr) {
		return ERR_UNAVAILABLE;
	}

	return save_jpg_func(p_path, Ref<Image>((Image *)this), p_quality);
}

Vector<uint8_t> Image::save_png_to_buffer() const {
	if (save_png_buffer_func == nullptr) {
		return Vector<uint8_t>();
	}

	return save_png_buffer_func(Ref<Image>((Image *)this));
}

Vector<uint8_t> Image::save_jpg_to_buffer(float p_quality) const {
	if (save_jpg_buffer_func == nullptr) {
		return Vector<uint8_t>();
	}

	return save_jpg_buffer_func(Ref<Image>((Image *)this), p_quality);
}

Error Image::save_exr(const String &p_path, bool p_grayscale) const {
	if (save_exr_func == nullptr) {
		return ERR_UNAVAILABLE;
	}

	return save_exr_func(p_path, Ref<Image>((Image *)this), p_grayscale);
}

Vector<uint8_t> Image::save_exr_to_buffer(bool p_grayscale) const {
	if (save_exr_buffer_func == nullptr) {
		return Vector<uint8_t>();
	}
	return save_exr_buffer_func(Ref<Image>((Image *)this), p_grayscale);
}

Error Image::save_webp(const String &p_path, const bool p_lossy, const float p_quality) const {
	if (save_webp_func == nullptr) {
		return ERR_UNAVAILABLE;
	}
	ERR_FAIL_COND_V_MSG(p_lossy && !(0.0f <= p_quality && p_quality <= 1.0f), ERR_INVALID_PARAMETER, "The WebP lossy quality was set to " + rtos(p_quality) + ", which is not valid. WebP lossy quality must be between 0.0 and 1.0 (inclusive).");

	return save_webp_func(p_path, Ref<Image>((Image *)this), p_lossy, p_quality);
}

Vector<uint8_t> Image::save_webp_to_buffer(const bool p_lossy, const float p_quality) const {
	if (save_webp_buffer_func == nullptr) {
		return Vector<uint8_t>();
	}
	ERR_FAIL_COND_V_MSG(p_lossy && !(0.0f <= p_quality && p_quality <= 1.0f), Vector<uint8_t>(), "The WebP lossy quality was set to " + rtos(p_quality) + ", which is not valid. WebP lossy quality must be between 0.0 and 1.0 (inclusive).");

	return save_webp_buffer_func(Ref<Image>((Image *)this), p_lossy, p_quality);
}

int Image::get_image_data_size(int p_width, int p_height, Format p_format, bool p_mipmaps) {
	int mm;
	return _get_dst_image_size(p_width, p_height, p_format, mm, p_mipmaps ? -1 : 0);
}

int Image::get_image_required_mipmaps(int p_width, int p_height, Format p_format) {
	int mm;
	_get_dst_image_size(p_width, p_height, p_format, mm, -1);
	return mm;
}

Size2i Image::get_image_mipmap_size(int p_width, int p_height, Format p_format, int p_mipmap) {
	int mm;
	Size2i ret;
	_get_dst_image_size(p_width, p_height, p_format, mm, p_mipmap, &ret.x, &ret.y);
	return ret;
}

int Image::get_image_mipmap_offset(int p_width, int p_height, Format p_format, int p_mipmap) {
	if (p_mipmap <= 0) {
		return 0;
	}
	int mm;
	return _get_dst_image_size(p_width, p_height, p_format, mm, p_mipmap - 1);
}

int Image::get_image_mipmap_offset_and_dimensions(int p_width, int p_height, Format p_format, int p_mipmap, int &r_w, int &r_h) {
	if (p_mipmap <= 0) {
		r_w = p_width;
		r_h = p_height;
		return 0;
	}
	int mm;
	return _get_dst_image_size(p_width, p_height, p_format, mm, p_mipmap - 1, &r_w, &r_h);
}

bool Image::is_compressed() const {
	return format > FORMAT_RGBE9995;
}

Error Image::decompress() {
	if (((format >= FORMAT_DXT1 && format <= FORMAT_RGTC_RG) || (format == FORMAT_DXT5_RA_AS_RG)) && _image_decompress_bc) {
		_image_decompress_bc(this);
	} else if (format >= FORMAT_BPTC_RGBA && format <= FORMAT_BPTC_RGBFU && _image_decompress_bptc) {
		_image_decompress_bptc(this);
	} else if (format == FORMAT_ETC && _image_decompress_etc1) {
		_image_decompress_etc1(this);
	} else if (format >= FORMAT_ETC2_R11 && format <= FORMAT_ETC2_RA_AS_RG && _image_decompress_etc2) {
		_image_decompress_etc2(this);
	} else if (format >= FORMAT_ASTC_4x4 && format <= FORMAT_ASTC_8x8_HDR && _image_decompress_astc) {
		_image_decompress_astc(this);
	} else {
		return ERR_UNAVAILABLE;
	}
	return OK;
}

Error Image::compress(CompressMode p_mode, CompressSource p_source, ASTCFormat p_astc_format) {
	ERR_FAIL_INDEX_V_MSG(p_mode, COMPRESS_MAX, ERR_INVALID_PARAMETER, "Invalid compress mode.");
	ERR_FAIL_INDEX_V_MSG(p_source, COMPRESS_SOURCE_MAX, ERR_INVALID_PARAMETER, "Invalid compress source.");
	return compress_from_channels(p_mode, detect_used_channels(p_source), p_astc_format);
}

Error Image::compress_from_channels(CompressMode p_mode, UsedChannels p_channels, ASTCFormat p_astc_format) {
	ERR_FAIL_COND_V(data.is_empty(), ERR_INVALID_DATA);

	switch (p_mode) {
		case COMPRESS_S3TC: {
			ERR_FAIL_COND_V(!_image_compress_bc_func, ERR_UNAVAILABLE);
			_image_compress_bc_func(this, p_channels);
		} break;
		case COMPRESS_ETC: {
			ERR_FAIL_COND_V(!_image_compress_etc1_func, ERR_UNAVAILABLE);
			_image_compress_etc1_func(this);
		} break;
		case COMPRESS_ETC2: {
			ERR_FAIL_COND_V(!_image_compress_etc2_func, ERR_UNAVAILABLE);
			_image_compress_etc2_func(this, p_channels);
		} break;
		case COMPRESS_BPTC: {
			ERR_FAIL_COND_V(!_image_compress_bptc_func, ERR_UNAVAILABLE);
			_image_compress_bptc_func(this, p_channels);
		} break;
		case COMPRESS_ASTC: {
			ERR_FAIL_COND_V(!_image_compress_astc_func, ERR_UNAVAILABLE);
			_image_compress_astc_func(this, p_astc_format);
		} break;
		case COMPRESS_MAX: {
			ERR_FAIL_V(ERR_INVALID_PARAMETER);
		} break;
	}

	return OK;
}

Image::Image(const char **p_xpm) {
	width = 0;
	height = 0;
	mipmaps = false;
	format = FORMAT_L8;

	initialize_data(p_xpm);
}

Image::Image(int p_width, int p_height, bool p_use_mipmaps, Format p_format) {
	width = 0;
	height = 0;
	mipmaps = p_use_mipmaps;
	format = FORMAT_L8;

	initialize_data(p_width, p_height, p_use_mipmaps, p_format);
}

Image::Image(int p_width, int p_height, bool p_mipmaps, Format p_format, const Vector<uint8_t> &p_data) {
	width = 0;
	height = 0;
	mipmaps = p_mipmaps;
	format = FORMAT_L8;

	initialize_data(p_width, p_height, p_mipmaps, p_format, p_data);
}

Rect2i Image::get_used_rect() const {
	if (format != FORMAT_LA8 && format != FORMAT_RGBA8 && format != FORMAT_RGBAF && format != FORMAT_RGBAH && format != FORMAT_RGBA4444 && format != FORMAT_RGB565) {
		return Rect2i(0, 0, width, height);
	}

	int len = data.size();

	if (len == 0) {
		return Rect2i();
	}

	int minx = 0xFFFFFF, miny = 0xFFFFFFF;
	int maxx = -1, maxy = -1;
	for (int j = 0; j < height; j++) {
		for (int i = 0; i < width; i++) {
			if (!(get_pixel(i, j).a > 0)) {
				continue;
			}
			if (i > maxx) {
				maxx = i;
			}
			if (j > maxy) {
				maxy = j;
			}
			if (i < minx) {
				minx = i;
			}
			if (j < miny) {
				miny = j;
			}
		}
	}

	if (maxx == -1) {
		return Rect2i();
	} else {
		return Rect2i(minx, miny, maxx - minx + 1, maxy - miny + 1);
	}
}

Ref<Image> Image::get_region(const Rect2i &p_region) const {
	Ref<Image> img = memnew(Image(p_region.size.x, p_region.size.y, mipmaps, format));
	img->blit_rect(Ref<Image>((Image *)this), p_region, Point2i(0, 0));
	return img;
}

void Image::_get_clipped_src_and_dest_rects(const Ref<Image> &p_src, const Rect2i &p_src_rect, const Point2i &p_dest, Rect2i &r_clipped_src_rect, Rect2i &r_clipped_dest_rect) const {
	r_clipped_dest_rect.position = p_dest;
	r_clipped_src_rect = p_src_rect;

	if (r_clipped_src_rect.position.x < 0) {
		r_clipped_dest_rect.position.x -= r_clipped_src_rect.position.x;
		r_clipped_src_rect.size.x += r_clipped_src_rect.position.x;
		r_clipped_src_rect.position.x = 0;
	}
	if (r_clipped_src_rect.position.y < 0) {
		r_clipped_dest_rect.position.y -= r_clipped_src_rect.position.y;
		r_clipped_src_rect.size.y += r_clipped_src_rect.position.y;
		r_clipped_src_rect.position.y = 0;
	}

	if (r_clipped_dest_rect.position.x < 0) {
		r_clipped_src_rect.position.x -= r_clipped_dest_rect.position.x;
		r_clipped_src_rect.size.x += r_clipped_dest_rect.position.x;
		r_clipped_dest_rect.position.x = 0;
	}
	if (r_clipped_dest_rect.position.y < 0) {
		r_clipped_src_rect.position.y -= r_clipped_dest_rect.position.y;
		r_clipped_src_rect.size.y += r_clipped_dest_rect.position.y;
		r_clipped_dest_rect.position.y = 0;
	}

	r_clipped_src_rect.size.x = MAX(0, MIN(r_clipped_src_rect.size.x, MIN(p_src->width - r_clipped_src_rect.position.x, width - r_clipped_dest_rect.position.x)));
	r_clipped_src_rect.size.y = MAX(0, MIN(r_clipped_src_rect.size.y, MIN(p_src->height - r_clipped_src_rect.position.y, height - r_clipped_dest_rect.position.y)));

	r_clipped_dest_rect.size.x = r_clipped_src_rect.size.x;
	r_clipped_dest_rect.size.y = r_clipped_src_rect.size.y;
}

void Image::blit_rect(const Ref<Image> &p_src, const Rect2i &p_src_rect, const Point2i &p_dest) {
	ERR_FAIL_COND_MSG(p_src.is_null(), "It's not a reference to a valid Image object.");
	int dsize = data.size();
	int srcdsize = p_src->data.size();
	ERR_FAIL_COND(dsize == 0);
	ERR_FAIL_COND(srcdsize == 0);
	ERR_FAIL_COND(format != p_src->format);
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot blit_rect in compressed or custom image formats.");

	Rect2i src_rect;
	Rect2i dest_rect;
	_get_clipped_src_and_dest_rects(p_src, p_src_rect, p_dest, src_rect, dest_rect);
	if (!src_rect.has_area() || !dest_rect.has_area()) {
		return;
	}

	uint8_t *wp = data.ptrw();
	uint8_t *dst_data_ptr = wp;

	const uint8_t *rp = p_src->data.ptr();
	const uint8_t *src_data_ptr = rp;

	int pixel_size = get_format_pixel_size(format);

	for (int i = 0; i < dest_rect.size.y; i++) {
		for (int j = 0; j < dest_rect.size.x; j++) {
			int src_x = src_rect.position.x + j;
			int src_y = src_rect.position.y + i;

			int dst_x = dest_rect.position.x + j;
			int dst_y = dest_rect.position.y + i;

			const uint8_t *src = &src_data_ptr[(src_y * p_src->width + src_x) * pixel_size];
			uint8_t *dst = &dst_data_ptr[(dst_y * width + dst_x) * pixel_size];

			for (int k = 0; k < pixel_size; k++) {
				dst[k] = src[k];
			}
		}
	}
}

void Image::blit_rect_mask(const Ref<Image> &p_src, const Ref<Image> &p_mask, const Rect2i &p_src_rect, const Point2i &p_dest) {
	ERR_FAIL_COND_MSG(p_src.is_null(), "It's not a reference to a valid Image object.");
	ERR_FAIL_COND_MSG(p_mask.is_null(), "It's not a reference to a valid Image object.");
	int dsize = data.size();
	int srcdsize = p_src->data.size();
	int maskdsize = p_mask->data.size();
	ERR_FAIL_COND(dsize == 0);
	ERR_FAIL_COND(srcdsize == 0);
	ERR_FAIL_COND(maskdsize == 0);
	ERR_FAIL_COND_MSG(p_src->width != p_mask->width, "Source image width is different from mask width.");
	ERR_FAIL_COND_MSG(p_src->height != p_mask->height, "Source image height is different from mask height.");
	ERR_FAIL_COND(format != p_src->format);

	Rect2i src_rect;
	Rect2i dest_rect;
	_get_clipped_src_and_dest_rects(p_src, p_src_rect, p_dest, src_rect, dest_rect);
	if (!src_rect.has_area() || !dest_rect.has_area()) {
		return;
	}

	uint8_t *wp = data.ptrw();
	uint8_t *dst_data_ptr = wp;

	const uint8_t *rp = p_src->data.ptr();
	const uint8_t *src_data_ptr = rp;

	int pixel_size = get_format_pixel_size(format);

	Ref<Image> msk = p_mask;

	for (int i = 0; i < dest_rect.size.y; i++) {
		for (int j = 0; j < dest_rect.size.x; j++) {
			int src_x = src_rect.position.x + j;
			int src_y = src_rect.position.y + i;

			if (msk->get_pixel(src_x, src_y).a != 0) {
				int dst_x = dest_rect.position.x + j;
				int dst_y = dest_rect.position.y + i;

				const uint8_t *src = &src_data_ptr[(src_y * p_src->width + src_x) * pixel_size];
				uint8_t *dst = &dst_data_ptr[(dst_y * width + dst_x) * pixel_size];

				for (int k = 0; k < pixel_size; k++) {
					dst[k] = src[k];
				}
			}
		}
	}
}

void Image::blend_rect(const Ref<Image> &p_src, const Rect2i &p_src_rect, const Point2i &p_dest) {
	ERR_FAIL_COND_MSG(p_src.is_null(), "It's not a reference to a valid Image object.");
	int dsize = data.size();
	int srcdsize = p_src->data.size();
	ERR_FAIL_COND(dsize == 0);
	ERR_FAIL_COND(srcdsize == 0);
	ERR_FAIL_COND(format != p_src->format);

	Rect2i src_rect;
	Rect2i dest_rect;
	_get_clipped_src_and_dest_rects(p_src, p_src_rect, p_dest, src_rect, dest_rect);
	if (!src_rect.has_area() || !dest_rect.has_area()) {
		return;
	}

	Ref<Image> img = p_src;

	for (int i = 0; i < dest_rect.size.y; i++) {
		for (int j = 0; j < dest_rect.size.x; j++) {
			int src_x = src_rect.position.x + j;
			int src_y = src_rect.position.y + i;

			int dst_x = dest_rect.position.x + j;
			int dst_y = dest_rect.position.y + i;

			Color sc = img->get_pixel(src_x, src_y);
			if (sc.a != 0) {
				Color dc = get_pixel(dst_x, dst_y);
				dc = dc.blend(sc);
				set_pixel(dst_x, dst_y, dc);
			}
		}
	}
}

void Image::blend_rect_mask(const Ref<Image> &p_src, const Ref<Image> &p_mask, const Rect2i &p_src_rect, const Point2i &p_dest) {
	ERR_FAIL_COND_MSG(p_src.is_null(), "It's not a reference to a valid Image object.");
	ERR_FAIL_COND_MSG(p_mask.is_null(), "It's not a reference to a valid Image object.");
	int dsize = data.size();
	int srcdsize = p_src->data.size();
	int maskdsize = p_mask->data.size();
	ERR_FAIL_COND(dsize == 0);
	ERR_FAIL_COND(srcdsize == 0);
	ERR_FAIL_COND(maskdsize == 0);
	ERR_FAIL_COND_MSG(p_src->width != p_mask->width, "Source image width is different from mask width.");
	ERR_FAIL_COND_MSG(p_src->height != p_mask->height, "Source image height is different from mask height.");
	ERR_FAIL_COND(format != p_src->format);

	Rect2i src_rect;
	Rect2i dest_rect;
	_get_clipped_src_and_dest_rects(p_src, p_src_rect, p_dest, src_rect, dest_rect);
	if (!src_rect.has_area() || !dest_rect.has_area()) {
		return;
	}

	Ref<Image> img = p_src;
	Ref<Image> msk = p_mask;

	for (int i = 0; i < dest_rect.size.y; i++) {
		for (int j = 0; j < dest_rect.size.x; j++) {
			int src_x = src_rect.position.x + j;
			int src_y = src_rect.position.y + i;

			// If the mask's pixel is transparent then we skip it
			//Color c = msk->get_pixel(src_x, src_y);
			//if (c.a == 0) continue;
			if (msk->get_pixel(src_x, src_y).a != 0) {
				int dst_x = dest_rect.position.x + j;
				int dst_y = dest_rect.position.y + i;

				Color sc = img->get_pixel(src_x, src_y);
				if (sc.a != 0) {
					Color dc = get_pixel(dst_x, dst_y);
					dc = dc.blend(sc);
					set_pixel(dst_x, dst_y, dc);
				}
			}
		}
	}
}

// Repeats `p_pixel` `p_count` times in consecutive memory.
// Results in the original pixel and `p_count - 1` subsequent copies of it.
void Image::_repeat_pixel_over_subsequent_memory(uint8_t *p_pixel, int p_pixel_size, int p_count) {
	int offset = 1;
	for (int stride = 1; offset + stride <= p_count; stride *= 2) {
		memcpy(p_pixel + offset * p_pixel_size, p_pixel, stride * p_pixel_size);
		offset += stride;
	}
	if (offset < p_count) {
		memcpy(p_pixel + offset * p_pixel_size, p_pixel, (p_count - offset) * p_pixel_size);
	}
}

void Image::fill(const Color &p_color) {
	if (data.size() == 0) {
		return;
	}
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot fill in compressed or custom image formats.");

	uint8_t *dst_data_ptr = data.ptrw();

	int pixel_size = get_format_pixel_size(format);

	// Put first pixel with the format-aware API.
	_set_color_at_ofs(dst_data_ptr, 0, p_color);

	_repeat_pixel_over_subsequent_memory(dst_data_ptr, pixel_size, width * height);
}

void Image::fill_rect(const Rect2i &p_rect, const Color &p_color) {
	if (data.size() == 0) {
		return;
	}
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot fill rect in compressed or custom image formats.");

	Rect2i r = Rect2i(0, 0, width, height).intersection(p_rect.abs());
	if (!r.has_area()) {
		return;
	}

	uint8_t *dst_data_ptr = data.ptrw();

	int pixel_size = get_format_pixel_size(format);

	// Put first pixel with the format-aware API.
	uint8_t *rect_first_pixel_ptr = &dst_data_ptr[(r.position.y * width + r.position.x) * pixel_size];
	_set_color_at_ofs(rect_first_pixel_ptr, 0, p_color);

	if (r.size.x == width) {
		// No need to fill rows separately.
		_repeat_pixel_over_subsequent_memory(rect_first_pixel_ptr, pixel_size, width * r.size.y);
	} else {
		_repeat_pixel_over_subsequent_memory(rect_first_pixel_ptr, pixel_size, r.size.x);
		for (int y = 1; y < r.size.y; y++) {
			memcpy(rect_first_pixel_ptr + y * width * pixel_size, rect_first_pixel_ptr, r.size.x * pixel_size);
		}
	}
}

ImageMemLoadFunc Image::_png_mem_loader_func = nullptr;
ImageMemLoadFunc Image::_jpg_mem_loader_func = nullptr;
ImageMemLoadFunc Image::_webp_mem_loader_func = nullptr;
ImageMemLoadFunc Image::_tga_mem_loader_func = nullptr;
ImageMemLoadFunc Image::_bmp_mem_loader_func = nullptr;
ScalableImageMemLoadFunc Image::_svg_scalable_mem_loader_func = nullptr;
ImageMemLoadFunc Image::_ktx_mem_loader_func = nullptr;

void (*Image::_image_compress_bc_func)(Image *, Image::UsedChannels) = nullptr;
void (*Image::_image_compress_bptc_func)(Image *, Image::UsedChannels) = nullptr;
void (*Image::_image_compress_etc1_func)(Image *) = nullptr;
void (*Image::_image_compress_etc2_func)(Image *, Image::UsedChannels) = nullptr;
void (*Image::_image_compress_astc_func)(Image *, Image::ASTCFormat) = nullptr;
void (*Image::_image_decompress_bc)(Image *) = nullptr;
void (*Image::_image_decompress_bptc)(Image *) = nullptr;
void (*Image::_image_decompress_etc1)(Image *) = nullptr;
void (*Image::_image_decompress_etc2)(Image *) = nullptr;
void (*Image::_image_decompress_astc)(Image *) = nullptr;

Vector<uint8_t> (*Image::webp_lossy_packer)(const Ref<Image> &, float) = nullptr;
Vector<uint8_t> (*Image::webp_lossless_packer)(const Ref<Image> &) = nullptr;
Ref<Image> (*Image::webp_unpacker)(const Vector<uint8_t> &) = nullptr;
Vector<uint8_t> (*Image::png_packer)(const Ref<Image> &) = nullptr;
Ref<Image> (*Image::png_unpacker)(const Vector<uint8_t> &) = nullptr;
Vector<uint8_t> (*Image::basis_universal_packer)(const Ref<Image> &, Image::UsedChannels) = nullptr;
Ref<Image> (*Image::basis_universal_unpacker)(const Vector<uint8_t> &) = nullptr;
Ref<Image> (*Image::basis_universal_unpacker_ptr)(const uint8_t *, int) = nullptr;

void Image::_set_data(const Dictionary &p_data) {
	ERR_FAIL_COND(!p_data.has("width"));
	ERR_FAIL_COND(!p_data.has("height"));
	ERR_FAIL_COND(!p_data.has("format"));
	ERR_FAIL_COND(!p_data.has("mipmaps"));
	ERR_FAIL_COND(!p_data.has("data"));

	int dwidth = p_data["width"];
	int dheight = p_data["height"];
	String dformat = p_data["format"];
	bool dmipmaps = p_data["mipmaps"];
	Vector<uint8_t> ddata = p_data["data"];
	Format ddformat = FORMAT_MAX;
	for (int i = 0; i < FORMAT_MAX; i++) {
		if (dformat == get_format_name(Format(i))) {
			ddformat = Format(i);
			break;
		}
	}

	ERR_FAIL_COND(ddformat == FORMAT_MAX);

	initialize_data(dwidth, dheight, dmipmaps, ddformat, ddata);
}

Dictionary Image::_get_data() const {
	Dictionary d;
	d["width"] = width;
	d["height"] = height;
	d["format"] = get_format_name(format);
	d["mipmaps"] = mipmaps;
	d["data"] = data;
	return d;
}

Color Image::get_pixelv(const Point2i &p_point) const {
	return get_pixel(p_point.x, p_point.y);
}

Color Image::_get_color_at_ofs(const uint8_t *ptr, uint32_t ofs) const {
	switch (format) {
		case FORMAT_L8: {
			float l = ptr[ofs] / 255.0;
			return Color(l, l, l, 1);
		}
		case FORMAT_LA8: {
			float l = ptr[ofs * 2 + 0] / 255.0;
			float a = ptr[ofs * 2 + 1] / 255.0;
			return Color(l, l, l, a);
		}
		case FORMAT_R8: {
			float r = ptr[ofs] / 255.0;
			return Color(r, 0, 0, 1);
		}
		case FORMAT_RG8: {
			float r = ptr[ofs * 2 + 0] / 255.0;
			float g = ptr[ofs * 2 + 1] / 255.0;
			return Color(r, g, 0, 1);
		}
		case FORMAT_RGB8: {
			float r = ptr[ofs * 3 + 0] / 255.0;
			float g = ptr[ofs * 3 + 1] / 255.0;
			float b = ptr[ofs * 3 + 2] / 255.0;
			return Color(r, g, b, 1);
		}
		case FORMAT_RGBA8: {
			float r = ptr[ofs * 4 + 0] / 255.0;
			float g = ptr[ofs * 4 + 1] / 255.0;
			float b = ptr[ofs * 4 + 2] / 255.0;
			float a = ptr[ofs * 4 + 3] / 255.0;
			return Color(r, g, b, a);
		}
		case FORMAT_RGBA4444: {
			uint16_t u = ((uint16_t *)ptr)[ofs];
			float r = ((u >> 12) & 0xF) / 15.0;
			float g = ((u >> 8) & 0xF) / 15.0;
			float b = ((u >> 4) & 0xF) / 15.0;
			float a = (u & 0xF) / 15.0;
			return Color(r, g, b, a);
		}
		case FORMAT_RGB565: {
			uint16_t u = ((uint16_t *)ptr)[ofs];
			float r = (u & 0x1F) / 31.0;
			float g = ((u >> 5) & 0x3F) / 63.0;
			float b = ((u >> 11) & 0x1F) / 31.0;
			return Color(r, g, b, 1.0);
		}
		case FORMAT_RF: {
			float r = ((float *)ptr)[ofs];
			return Color(r, 0, 0, 1);
		}
		case FORMAT_RGF: {
			float r = ((float *)ptr)[ofs * 2 + 0];
			float g = ((float *)ptr)[ofs * 2 + 1];
			return Color(r, g, 0, 1);
		}
		case FORMAT_RGBF: {
			float r = ((float *)ptr)[ofs * 3 + 0];
			float g = ((float *)ptr)[ofs * 3 + 1];
			float b = ((float *)ptr)[ofs * 3 + 2];
			return Color(r, g, b, 1);
		}
		case FORMAT_RGBAF: {
			float r = ((float *)ptr)[ofs * 4 + 0];
			float g = ((float *)ptr)[ofs * 4 + 1];
			float b = ((float *)ptr)[ofs * 4 + 2];
			float a = ((float *)ptr)[ofs * 4 + 3];
			return Color(r, g, b, a);
		}
		case FORMAT_RH: {
			uint16_t r = ((uint16_t *)ptr)[ofs];
			return Color(Math::half_to_float(r), 0, 0, 1);
		}
		case FORMAT_RGH: {
			uint16_t r = ((uint16_t *)ptr)[ofs * 2 + 0];
			uint16_t g = ((uint16_t *)ptr)[ofs * 2 + 1];
			return Color(Math::half_to_float(r), Math::half_to_float(g), 0, 1);
		}
		case FORMAT_RGBH: {
			uint16_t r = ((uint16_t *)ptr)[ofs * 3 + 0];
			uint16_t g = ((uint16_t *)ptr)[ofs * 3 + 1];
			uint16_t b = ((uint16_t *)ptr)[ofs * 3 + 2];
			return Color(Math::half_to_float(r), Math::half_to_float(g), Math::half_to_float(b), 1);
		}
		case FORMAT_RGBAH: {
			uint16_t r = ((uint16_t *)ptr)[ofs * 4 + 0];
			uint16_t g = ((uint16_t *)ptr)[ofs * 4 + 1];
			uint16_t b = ((uint16_t *)ptr)[ofs * 4 + 2];
			uint16_t a = ((uint16_t *)ptr)[ofs * 4 + 3];
			return Color(Math::half_to_float(r), Math::half_to_float(g), Math::half_to_float(b), Math::half_to_float(a));
		}
		case FORMAT_RGBE9995: {
			return Color::from_rgbe9995(((uint32_t *)ptr)[ofs]);
		}
		default: {
			ERR_FAIL_V_MSG(Color(), "Can't get_pixel() on compressed image, sorry.");
		}
	}
}

void Image::_set_color_at_ofs(uint8_t *ptr, uint32_t ofs, const Color &p_color) {
	switch (format) {
		case FORMAT_L8: {
			ptr[ofs] = uint8_t(CLAMP(p_color.get_v() * 255.0, 0, 255));
		} break;
		case FORMAT_LA8: {
			ptr[ofs * 2 + 0] = uint8_t(CLAMP(p_color.get_v() * 255.0, 0, 255));
			ptr[ofs * 2 + 1] = uint8_t(CLAMP(p_color.a * 255.0, 0, 255));
		} break;
		case FORMAT_R8: {
			ptr[ofs] = uint8_t(CLAMP(p_color.r * 255.0, 0, 255));
		} break;
		case FORMAT_RG8: {
			ptr[ofs * 2 + 0] = uint8_t(CLAMP(p_color.r * 255.0, 0, 255));
			ptr[ofs * 2 + 1] = uint8_t(CLAMP(p_color.g * 255.0, 0, 255));
		} break;
		case FORMAT_RGB8: {
			ptr[ofs * 3 + 0] = uint8_t(CLAMP(p_color.r * 255.0, 0, 255));
			ptr[ofs * 3 + 1] = uint8_t(CLAMP(p_color.g * 255.0, 0, 255));
			ptr[ofs * 3 + 2] = uint8_t(CLAMP(p_color.b * 255.0, 0, 255));
		} break;
		case FORMAT_RGBA8: {
			ptr[ofs * 4 + 0] = uint8_t(CLAMP(p_color.r * 255.0, 0, 255));
			ptr[ofs * 4 + 1] = uint8_t(CLAMP(p_color.g * 255.0, 0, 255));
			ptr[ofs * 4 + 2] = uint8_t(CLAMP(p_color.b * 255.0, 0, 255));
			ptr[ofs * 4 + 3] = uint8_t(CLAMP(p_color.a * 255.0, 0, 255));

		} break;
		case FORMAT_RGBA4444: {
			uint16_t rgba = 0;

			rgba = uint16_t(CLAMP(p_color.r * 15.0, 0, 15)) << 12;
			rgba |= uint16_t(CLAMP(p_color.g * 15.0, 0, 15)) << 8;
			rgba |= uint16_t(CLAMP(p_color.b * 15.0, 0, 15)) << 4;
			rgba |= uint16_t(CLAMP(p_color.a * 15.0, 0, 15));

			((uint16_t *)ptr)[ofs] = rgba;

		} break;
		case FORMAT_RGB565: {
			uint16_t rgba = 0;

			rgba = uint16_t(CLAMP(p_color.r * 31.0, 0, 31));
			rgba |= uint16_t(CLAMP(p_color.g * 63.0, 0, 33)) << 5;
			rgba |= uint16_t(CLAMP(p_color.b * 31.0, 0, 31)) << 11;

			((uint16_t *)ptr)[ofs] = rgba;

		} break;
		case FORMAT_RF: {
			((float *)ptr)[ofs] = p_color.r;
		} break;
		case FORMAT_RGF: {
			((float *)ptr)[ofs * 2 + 0] = p_color.r;
			((float *)ptr)[ofs * 2 + 1] = p_color.g;
		} break;
		case FORMAT_RGBF: {
			((float *)ptr)[ofs * 3 + 0] = p_color.r;
			((float *)ptr)[ofs * 3 + 1] = p_color.g;
			((float *)ptr)[ofs * 3 + 2] = p_color.b;
		} break;
		case FORMAT_RGBAF: {
			((float *)ptr)[ofs * 4 + 0] = p_color.r;
			((float *)ptr)[ofs * 4 + 1] = p_color.g;
			((float *)ptr)[ofs * 4 + 2] = p_color.b;
			((float *)ptr)[ofs * 4 + 3] = p_color.a;
		} break;
		case FORMAT_RH: {
			((uint16_t *)ptr)[ofs] = Math::make_half_float(p_color.r);
		} break;
		case FORMAT_RGH: {
			((uint16_t *)ptr)[ofs * 2 + 0] = Math::make_half_float(p_color.r);
			((uint16_t *)ptr)[ofs * 2 + 1] = Math::make_half_float(p_color.g);
		} break;
		case FORMAT_RGBH: {
			((uint16_t *)ptr)[ofs * 3 + 0] = Math::make_half_float(p_color.r);
			((uint16_t *)ptr)[ofs * 3 + 1] = Math::make_half_float(p_color.g);
			((uint16_t *)ptr)[ofs * 3 + 2] = Math::make_half_float(p_color.b);
		} break;
		case FORMAT_RGBAH: {
			((uint16_t *)ptr)[ofs * 4 + 0] = Math::make_half_float(p_color.r);
			((uint16_t *)ptr)[ofs * 4 + 1] = Math::make_half_float(p_color.g);
			((uint16_t *)ptr)[ofs * 4 + 2] = Math::make_half_float(p_color.b);
			((uint16_t *)ptr)[ofs * 4 + 3] = Math::make_half_float(p_color.a);
		} break;
		case FORMAT_RGBE9995: {
			((uint32_t *)ptr)[ofs] = p_color.to_rgbe9995();

		} break;
		default: {
			ERR_FAIL_MSG("Can't set_pixel() on compressed image, sorry.");
		}
	}
}

Color Image::get_pixel(int p_x, int p_y) const {
#ifdef DEBUG_ENABLED
	ERR_FAIL_INDEX_V(p_x, width, Color());
	ERR_FAIL_INDEX_V(p_y, height, Color());
#endif

	uint32_t ofs = p_y * width + p_x;
	return _get_color_at_ofs(data.ptr(), ofs);
}

void Image::set_pixelv(const Point2i &p_point, const Color &p_color) {
	set_pixel(p_point.x, p_point.y, p_color);
}

void Image::set_pixel(int p_x, int p_y, const Color &p_color) {
#ifdef DEBUG_ENABLED
	ERR_FAIL_INDEX(p_x, width);
	ERR_FAIL_INDEX(p_y, height);
#endif

	uint32_t ofs = p_y * width + p_x;
	_set_color_at_ofs(data.ptrw(), ofs, p_color);
}

void Image::adjust_bcs(float p_brightness, float p_contrast, float p_saturation) {
	ERR_FAIL_COND_MSG(!_can_modify(format), "Cannot adjust_bcs in compressed or custom image formats.");

	uint8_t *w = data.ptrw();
	uint32_t pixel_size = get_format_pixel_size(format);
	uint32_t pixel_count = data.size() / pixel_size;

	for (uint32_t i = 0; i < pixel_count; i++) {
		Color c = _get_color_at_ofs(w, i);
		Vector3 rgb(c.r, c.g, c.b);

		rgb *= p_brightness;
		rgb = Vector3(0.5, 0.5, 0.5).lerp(rgb, p_contrast);
		float center = (rgb.x + rgb.y + rgb.z) / 3.0;
		rgb = Vector3(center, center, center).lerp(rgb, p_saturation);
		c.r = rgb.x;
		c.g = rgb.y;
		c.b = rgb.z;
		_set_color_at_ofs(w, i, c);
	}
}

Image::UsedChannels Image::detect_used_channels(CompressSource p_source) const {
	ERR_FAIL_COND_V(data.size() == 0, USED_CHANNELS_RGBA);
	ERR_FAIL_COND_V(is_compressed(), USED_CHANNELS_RGBA);
	bool r = false, g = false, b = false, a = false, c = false;

	const uint8_t *data_ptr = data.ptr();

	uint32_t data_total = width * height;

	for (uint32_t i = 0; i < data_total; i++) {
		Color col = _get_color_at_ofs(data_ptr, i);

		if (col.r > 0.001) {
			r = true;
		}
		if (col.g > 0.001) {
			g = true;
		}
		if (col.b > 0.001) {
			b = true;
		}
		if (col.a < 0.999) {
			a = true;
		}

		if (col.r != col.b || col.r != col.g || col.b != col.g) {
			c = true;
		}
	}

	UsedChannels used_channels;

	if (!c && !a) {
		used_channels = USED_CHANNELS_L;
	} else if (!c && a) {
		used_channels = USED_CHANNELS_LA;
	} else if (r && !g && !b && !a) {
		used_channels = USED_CHANNELS_R;
	} else if (r && g && !b && !a) {
		used_channels = USED_CHANNELS_RG;
	} else if (r && g && b && !a) {
		used_channels = USED_CHANNELS_RGB;
	} else {
		used_channels = USED_CHANNELS_RGBA;
	}

	if (p_source == COMPRESS_SOURCE_SRGB && (used_channels == USED_CHANNELS_R || used_channels == USED_CHANNELS_RG)) {
		//R and RG do not support SRGB
		used_channels = USED_CHANNELS_RGB;
	}

	if (p_source == COMPRESS_SOURCE_NORMAL) {
		//use RG channels only for normal
		used_channels = USED_CHANNELS_RG;
	}

	return used_channels;
}

void Image::optimize_channels() {
	switch (detect_used_channels()) {
		case USED_CHANNELS_L:
			convert(FORMAT_L8);
			break;
		case USED_CHANNELS_LA:
			convert(FORMAT_LA8);
			break;
		case USED_CHANNELS_R:
			convert(FORMAT_R8);
			break;
		case USED_CHANNELS_RG:
			convert(FORMAT_RG8);
			break;
		case USED_CHANNELS_RGB:
			convert(FORMAT_RGB8);
			break;
		case USED_CHANNELS_RGBA:
			convert(FORMAT_RGBA8);
			break;
	}
}

void Image::_bind_methods() {
	ClassDB::bind_method(D_METHOD("get_width"), &Image::get_width);
	ClassDB::bind_method(D_METHOD("get_height"), &Image::get_height);
	ClassDB::bind_method(D_METHOD("get_size"), &Image::get_size);
	ClassDB::bind_method(D_METHOD("has_mipmaps"), &Image::has_mipmaps);
	ClassDB::bind_method(D_METHOD("get_format"), &Image::get_format);
	ClassDB::bind_method(D_METHOD("get_data"), &Image::get_data);

	ClassDB::bind_method(D_METHOD("convert", "format"), &Image::convert);

	ClassDB::bind_method(D_METHOD("get_mipmap_offset", "mipmap"), &Image::get_mipmap_offset);

	ClassDB::bind_method(D_METHOD("resize_to_po2", "square", "interpolation"), &Image::resize_to_po2, DEFVAL(false), DEFVAL(INTERPOLATE_BILINEAR));
	ClassDB::bind_method(D_METHOD("resize", "width", "height", "interpolation"), &Image::resize, DEFVAL(INTERPOLATE_BILINEAR));
	ClassDB::bind_method(D_METHOD("shrink_x2"), &Image::shrink_x2);

	ClassDB::bind_method(D_METHOD("crop", "width", "height"), &Image::crop);
	ClassDB::bind_method(D_METHOD("flip_x"), &Image::flip_x);
	ClassDB::bind_method(D_METHOD("flip_y"), &Image::flip_y);
	ClassDB::bind_method(D_METHOD("generate_mipmaps", "renormalize"), &Image::generate_mipmaps, DEFVAL(false));
	ClassDB::bind_method(D_METHOD("clear_mipmaps"), &Image::clear_mipmaps);

	ClassDB::bind_static_method("Image", D_METHOD("create", "width", "height", "use_mipmaps", "format"), &Image::create_empty);
	ClassDB::bind_static_method("Image", D_METHOD("create_from_data", "width", "height", "use_mipmaps", "format", "data"), &Image::create_from_data);
	ClassDB::bind_method(D_METHOD("set_data", "width", "height", "use_mipmaps", "format", "data"), &Image::set_data);

	ClassDB::bind_method(D_METHOD("is_empty"), &Image::is_empty);

	ClassDB::bind_method(D_METHOD("load", "path"), &Image::load);
	ClassDB::bind_static_method("Image", D_METHOD("load_from_file", "path"), &Image::load_from_file);
	ClassDB::bind_method(D_METHOD("save_png", "path"), &Image::save_png);
	ClassDB::bind_method(D_METHOD("save_png_to_buffer"), &Image::save_png_to_buffer);
	ClassDB::bind_method(D_METHOD("save_jpg", "path", "quality"), &Image::save_jpg, DEFVAL(0.75));
	ClassDB::bind_method(D_METHOD("save_jpg_to_buffer", "quality"), &Image::save_jpg_to_buffer, DEFVAL(0.75));
	ClassDB::bind_method(D_METHOD("save_exr", "path", "grayscale"), &Image::save_exr, DEFVAL(false));
	ClassDB::bind_method(D_METHOD("save_exr_to_buffer", "grayscale"), &Image::save_exr_to_buffer, DEFVAL(false));
	ClassDB::bind_method(D_METHOD("save_webp", "path", "lossy", "quality"), &Image::save_webp, DEFVAL(false), DEFVAL(0.75f));
	ClassDB::bind_method(D_METHOD("save_webp_to_buffer", "lossy", "quality"), &Image::save_webp_to_buffer, DEFVAL(false), DEFVAL(0.75f));

	ClassDB::bind_method(D_METHOD("detect_alpha"), &Image::detect_alpha);
	ClassDB::bind_method(D_METHOD("is_invisible"), &Image::is_invisible);

	ClassDB::bind_method(D_METHOD("detect_used_channels", "source"), &Image::detect_used_channels, DEFVAL(COMPRESS_SOURCE_GENERIC));
	ClassDB::bind_method(D_METHOD("compress", "mode", "source", "astc_format"), &Image::compress, DEFVAL(COMPRESS_SOURCE_GENERIC), DEFVAL(ASTC_FORMAT_4x4));
	ClassDB::bind_method(D_METHOD("compress_from_channels", "mode", "channels", "astc_format"), &Image::compress_from_channels, DEFVAL(ASTC_FORMAT_4x4));
	ClassDB::bind_method(D_METHOD("decompress"), &Image::decompress);
	ClassDB::bind_method(D_METHOD("is_compressed"), &Image::is_compressed);

	ClassDB::bind_method(D_METHOD("rotate_90", "direction"), &Image::rotate_90);
	ClassDB::bind_method(D_METHOD("rotate_180"), &Image::rotate_180);

	ClassDB::bind_method(D_METHOD("fix_alpha_edges"), &Image::fix_alpha_edges);
	ClassDB::bind_method(D_METHOD("premultiply_alpha"), &Image::premultiply_alpha);
	ClassDB::bind_method(D_METHOD("srgb_to_linear"), &Image::srgb_to_linear);
	ClassDB::bind_method(D_METHOD("normal_map_to_xy"), &Image::normal_map_to_xy);
	ClassDB::bind_method(D_METHOD("rgbe_to_srgb"), &Image::rgbe_to_srgb);
	ClassDB::bind_method(D_METHOD("bump_map_to_normal_map", "bump_scale"), &Image::bump_map_to_normal_map, DEFVAL(1.0));

	ClassDB::bind_method(D_METHOD("compute_image_metrics", "compared_image", "use_luma"), &Image::compute_image_metrics);

	ClassDB::bind_method(D_METHOD("blit_rect", "src", "src_rect", "dst"), &Image::blit_rect);
	ClassDB::bind_method(D_METHOD("blit_rect_mask", "src", "mask", "src_rect", "dst"), &Image::blit_rect_mask);
	ClassDB::bind_method(D_METHOD("blend_rect", "src", "src_rect", "dst"), &Image::blend_rect);
	ClassDB::bind_method(D_METHOD("blend_rect_mask", "src", "mask", "src_rect", "dst"), &Image::blend_rect_mask);
	ClassDB::bind_method(D_METHOD("fill", "color"), &Image::fill);
	ClassDB::bind_method(D_METHOD("fill_rect", "rect", "color"), &Image::fill_rect);

	ClassDB::bind_method(D_METHOD("get_used_rect"), &Image::get_used_rect);
	ClassDB::bind_method(D_METHOD("get_region", "region"), &Image::get_region);

	ClassDB::bind_method(D_METHOD("copy_from", "src"), &Image::copy_internals_from);

	ClassDB::bind_method(D_METHOD("_set_data", "data"), &Image::_set_data);
	ClassDB::bind_method(D_METHOD("_get_data"), &Image::_get_data);

	ClassDB::bind_method(D_METHOD("get_pixelv", "point"), &Image::get_pixelv);
	ClassDB::bind_method(D_METHOD("get_pixel", "x", "y"), &Image::get_pixel);
	ClassDB::bind_method(D_METHOD("set_pixelv", "point", "color"), &Image::set_pixelv);
	ClassDB::bind_method(D_METHOD("set_pixel", "x", "y", "color"), &Image::set_pixel);

	ClassDB::bind_method(D_METHOD("adjust_bcs", "brightness", "contrast", "saturation"), &Image::adjust_bcs);

	ClassDB::bind_method(D_METHOD("load_png_from_buffer", "buffer"), &Image::load_png_from_buffer);
	ClassDB::bind_method(D_METHOD("load_jpg_from_buffer", "buffer"), &Image::load_jpg_from_buffer);
	ClassDB::bind_method(D_METHOD("load_webp_from_buffer", "buffer"), &Image::load_webp_from_buffer);
	ClassDB::bind_method(D_METHOD("load_tga_from_buffer", "buffer"), &Image::load_tga_from_buffer);
	ClassDB::bind_method(D_METHOD("load_bmp_from_buffer", "buffer"), &Image::load_bmp_from_buffer);
	ClassDB::bind_method(D_METHOD("load_ktx_from_buffer", "buffer"), &Image::load_ktx_from_buffer);

	ClassDB::bind_method(D_METHOD("load_svg_from_buffer", "buffer", "scale"), &Image::load_svg_from_buffer, DEFVAL(1.0));
	ClassDB::bind_method(D_METHOD("load_svg_from_string", "svg_str", "scale"), &Image::load_svg_from_string, DEFVAL(1.0));

	ADD_PROPERTY(PropertyInfo(Variant::DICTIONARY, "data", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_STORAGE), "_set_data", "_get_data");

	BIND_CONSTANT(MAX_WIDTH);
	BIND_CONSTANT(MAX_HEIGHT);

	BIND_ENUM_CONSTANT(FORMAT_L8); //luminance
	BIND_ENUM_CONSTANT(FORMAT_LA8); //luminance-alpha
	BIND_ENUM_CONSTANT(FORMAT_R8);
	BIND_ENUM_CONSTANT(FORMAT_RG8);
	BIND_ENUM_CONSTANT(FORMAT_RGB8);
	BIND_ENUM_CONSTANT(FORMAT_RGBA8);
	BIND_ENUM_CONSTANT(FORMAT_RGBA4444);
	BIND_ENUM_CONSTANT(FORMAT_RGB565);
	BIND_ENUM_CONSTANT(FORMAT_RF); //float
	BIND_ENUM_CONSTANT(FORMAT_RGF);
	BIND_ENUM_CONSTANT(FORMAT_RGBF);
	BIND_ENUM_CONSTANT(FORMAT_RGBAF);
	BIND_ENUM_CONSTANT(FORMAT_RH); //half float
	BIND_ENUM_CONSTANT(FORMAT_RGH);
	BIND_ENUM_CONSTANT(FORMAT_RGBH);
	BIND_ENUM_CONSTANT(FORMAT_RGBAH);
	BIND_ENUM_CONSTANT(FORMAT_RGBE9995);
	BIND_ENUM_CONSTANT(FORMAT_DXT1); //s3tc bc1
	BIND_ENUM_CONSTANT(FORMAT_DXT3); //bc2
	BIND_ENUM_CONSTANT(FORMAT_DXT5); //bc3
	BIND_ENUM_CONSTANT(FORMAT_RGTC_R);
	BIND_ENUM_CONSTANT(FORMAT_RGTC_RG);
	BIND_ENUM_CONSTANT(FORMAT_BPTC_RGBA); //btpc bc6h
	BIND_ENUM_CONSTANT(FORMAT_BPTC_RGBF); //float /
	BIND_ENUM_CONSTANT(FORMAT_BPTC_RGBFU); //unsigned float
	BIND_ENUM_CONSTANT(FORMAT_ETC); //etc1
	BIND_ENUM_CONSTANT(FORMAT_ETC2_R11); //etc2
	BIND_ENUM_CONSTANT(FORMAT_ETC2_R11S); //signed ); NOT srgb.
	BIND_ENUM_CONSTANT(FORMAT_ETC2_RG11);
	BIND_ENUM_CONSTANT(FORMAT_ETC2_RG11S);
	BIND_ENUM_CONSTANT(FORMAT_ETC2_RGB8);
	BIND_ENUM_CONSTANT(FORMAT_ETC2_RGBA8);
	BIND_ENUM_CONSTANT(FORMAT_ETC2_RGB8A1);
	BIND_ENUM_CONSTANT(FORMAT_ETC2_RA_AS_RG);
	BIND_ENUM_CONSTANT(FORMAT_DXT5_RA_AS_RG);
	BIND_ENUM_CONSTANT(FORMAT_ASTC_4x4);
	BIND_ENUM_CONSTANT(FORMAT_ASTC_4x4_HDR);
	BIND_ENUM_CONSTANT(FORMAT_ASTC_8x8);
	BIND_ENUM_CONSTANT(FORMAT_ASTC_8x8_HDR);
	BIND_ENUM_CONSTANT(FORMAT_MAX);

	BIND_ENUM_CONSTANT(INTERPOLATE_NEAREST);
	BIND_ENUM_CONSTANT(INTERPOLATE_BILINEAR);
	BIND_ENUM_CONSTANT(INTERPOLATE_CUBIC);
	BIND_ENUM_CONSTANT(INTERPOLATE_TRILINEAR);
	BIND_ENUM_CONSTANT(INTERPOLATE_LANCZOS);

	BIND_ENUM_CONSTANT(ALPHA_NONE);
	BIND_ENUM_CONSTANT(ALPHA_BIT);
	BIND_ENUM_CONSTANT(ALPHA_BLEND);

	BIND_ENUM_CONSTANT(COMPRESS_S3TC);
	BIND_ENUM_CONSTANT(COMPRESS_ETC);
	BIND_ENUM_CONSTANT(COMPRESS_ETC2);
	BIND_ENUM_CONSTANT(COMPRESS_BPTC);
	BIND_ENUM_CONSTANT(COMPRESS_ASTC);
	BIND_ENUM_CONSTANT(COMPRESS_MAX);

	BIND_ENUM_CONSTANT(USED_CHANNELS_L);
	BIND_ENUM_CONSTANT(USED_CHANNELS_LA);
	BIND_ENUM_CONSTANT(USED_CHANNELS_R);
	BIND_ENUM_CONSTANT(USED_CHANNELS_RG);
	BIND_ENUM_CONSTANT(USED_CHANNELS_RGB);
	BIND_ENUM_CONSTANT(USED_CHANNELS_RGBA);

	BIND_ENUM_CONSTANT(COMPRESS_SOURCE_GENERIC);
	BIND_ENUM_CONSTANT(COMPRESS_SOURCE_SRGB);
	BIND_ENUM_CONSTANT(COMPRESS_SOURCE_NORMAL);

	BIND_ENUM_CONSTANT(ASTC_FORMAT_4x4);
	BIND_ENUM_CONSTANT(ASTC_FORMAT_8x8);
}

void Image::set_compress_bc_func(void (*p_compress_func)(Image *, UsedChannels)) {
	_image_compress_bc_func = p_compress_func;
}

void Image::set_compress_bptc_func(void (*p_compress_func)(Image *, UsedChannels)) {
	_image_compress_bptc_func = p_compress_func;
}

void Image::normal_map_to_xy() {
	convert(Image::FORMAT_RGBA8);

	{
		int len = data.size() / 4;
		uint8_t *data_ptr = data.ptrw();

		for (int i = 0; i < len; i++) {
			data_ptr[(i << 2) + 3] = data_ptr[(i << 2) + 0]; //x to w
			data_ptr[(i << 2) + 0] = data_ptr[(i << 2) + 1]; //y to xz
			data_ptr[(i << 2) + 2] = data_ptr[(i << 2) + 1];
		}
	}

	convert(Image::FORMAT_LA8);
}

Ref<Image> Image::rgbe_to_srgb() {
	if (data.size() == 0) {
		return Ref<Image>();
	}

	ERR_FAIL_COND_V(format != FORMAT_RGBE9995, Ref<Image>());

	Ref<Image> new_image = create_empty(width, height, false, Image::FORMAT_RGB8);

	for (int row = 0; row < height; row++) {
		for (int col = 0; col < width; col++) {
			new_image->set_pixel(col, row, get_pixel(col, row).linear_to_srgb());
		}
	}

	if (has_mipmaps()) {
		new_image->generate_mipmaps();
	}

	return new_image;
}

Ref<Image> Image::get_image_from_mipmap(int p_mipamp) const {
	int ofs, size, w, h;
	get_mipmap_offset_size_and_dimensions(p_mipamp, ofs, size, w, h);

	Vector<uint8_t> new_data;
	new_data.resize(size);

	{
		uint8_t *wr = new_data.ptrw();
		const uint8_t *rd = data.ptr();
		memcpy(wr, rd + ofs, size);
	}

	Ref<Image> image;
	image.instantiate();
	image->width = w;
	image->height = h;
	image->format = format;
	image->data = new_data;

	image->mipmaps = false;
	return image;
}

void Image::bump_map_to_normal_map(float bump_scale) {
	ERR_FAIL_COND(!_can_modify(format));
	clear_mipmaps();
	convert(Image::FORMAT_RF);

	Vector<uint8_t> result_image; //rgba output
	result_image.resize(width * height * 4);

	{
		const uint8_t *rp = data.ptr();
		uint8_t *wp = result_image.ptrw();

		ERR_FAIL_COND(!rp);

		unsigned char *write_ptr = wp;
		float *read_ptr = (float *)rp;

		for (int ty = 0; ty < height; ty++) {
			int py = ty + 1;
			if (py >= height) {
				py -= height;
			}

			for (int tx = 0; tx < width; tx++) {
				int px = tx + 1;
				if (px >= width) {
					px -= width;
				}
				float here = read_ptr[ty * width + tx];
				float to_right = read_ptr[ty * width + px];
				float above = read_ptr[py * width + tx];
				Vector3 up = Vector3(0, 1, (here - above) * bump_scale);
				Vector3 across = Vector3(1, 0, (to_right - here) * bump_scale);

				Vector3 normal = across.cross(up);
				normal.normalize();

				write_ptr[((ty * width + tx) << 2) + 0] = (127.5 + normal.x * 127.5);
				write_ptr[((ty * width + tx) << 2) + 1] = (127.5 + normal.y * 127.5);
				write_ptr[((ty * width + tx) << 2) + 2] = (127.5 + normal.z * 127.5);
				write_ptr[((ty * width + tx) << 2) + 3] = 255;
			}
		}
	}
	format = FORMAT_RGBA8;
	data = result_image;
}

void Image::srgb_to_linear() {
	if (data.size() == 0) {
		return;
	}

	static const uint8_t srgb2lin[256] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 8, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 14, 14, 15, 15, 16, 16, 16, 17, 17, 18, 18, 19, 19, 20, 20, 21, 22, 22, 23, 23, 24, 24, 25, 26, 26, 27, 27, 28, 29, 29, 30, 31, 31, 32, 33, 33, 34, 35, 36, 36, 37, 38, 38, 39, 40, 41, 42, 42, 43, 44, 45, 46, 47, 47, 48, 49, 50, 51, 52, 53, 54, 55, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 70, 71, 72, 73, 74, 75, 76, 77, 78, 80, 81, 82, 83, 84, 85, 87, 88, 89, 90, 92, 93, 94, 95, 97, 98, 99, 101, 102, 103, 105, 106, 107, 109, 110, 112, 113, 114, 116, 117, 119, 120, 122, 123, 125, 126, 128, 129, 131, 132, 134, 135, 137, 139, 140, 142, 144, 145, 147, 148, 150, 152, 153, 155, 157, 159, 160, 162, 164, 166, 167, 169, 171, 173, 175, 176, 178, 180, 182, 184, 186, 188, 190, 192, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 218, 220, 222, 224, 226, 228, 230, 232, 235, 237, 239, 241, 243, 245, 248, 250, 252, 255 };

	ERR_FAIL_COND(format != FORMAT_RGB8 && format != FORMAT_RGBA8);

	if (format == FORMAT_RGBA8) {
		int len = data.size() / 4;
		uint8_t *data_ptr = data.ptrw();

		for (int i = 0; i < len; i++) {
			data_ptr[(i << 2) + 0] = srgb2lin[data_ptr[(i << 2) + 0]];
			data_ptr[(i << 2) + 1] = srgb2lin[data_ptr[(i << 2) + 1]];
			data_ptr[(i << 2) + 2] = srgb2lin[data_ptr[(i << 2) + 2]];
		}

	} else if (format == FORMAT_RGB8) {
		int len = data.size() / 3;
		uint8_t *data_ptr = data.ptrw();

		for (int i = 0; i < len; i++) {
			data_ptr[(i * 3) + 0] = srgb2lin[data_ptr[(i * 3) + 0]];
			data_ptr[(i * 3) + 1] = srgb2lin[data_ptr[(i * 3) + 1]];
			data_ptr[(i * 3) + 2] = srgb2lin[data_ptr[(i * 3) + 2]];
		}
	}
}

void Image::premultiply_alpha() {
	if (data.size() == 0) {
		return;
	}

	if (format != FORMAT_RGBA8) {
		return; //not needed
	}

	uint8_t *data_ptr = data.ptrw();

	for (int i = 0; i < height; i++) {
		for (int j = 0; j < width; j++) {
			uint8_t *ptr = &data_ptr[(i * width + j) * 4];

			ptr[0] = (uint16_t(ptr[0]) * uint16_t(ptr[3]) + 255U) >> 8;
			ptr[1] = (uint16_t(ptr[1]) * uint16_t(ptr[3]) + 255U) >> 8;
			ptr[2] = (uint16_t(ptr[2]) * uint16_t(ptr[3]) + 255U) >> 8;
		}
	}
}

void Image::fix_alpha_edges() {
	if (data.size() == 0) {
		return;
	}

	if (format != FORMAT_RGBA8) {
		return; //not needed
	}

	Vector<uint8_t> dcopy = data;
	const uint8_t *srcptr = dcopy.ptr();

	uint8_t *data_ptr = data.ptrw();

	const int max_radius = 4;
	const int alpha_threshold = 20;
	const int max_dist = 0x7FFFFFFF;

	for (int i = 0; i < height; i++) {
		for (int j = 0; j < width; j++) {
			const uint8_t *rptr = &srcptr[(i * width + j) * 4];
			uint8_t *wptr = &data_ptr[(i * width + j) * 4];

			if (rptr[3] >= alpha_threshold) {
				continue;
			}

			int closest_dist = max_dist;
			uint8_t closest_color[3];

			int from_x = MAX(0, j - max_radius);
			int to_x = MIN(width - 1, j + max_radius);
			int from_y = MAX(0, i - max_radius);
			int to_y = MIN(height - 1, i + max_radius);

			for (int k = from_y; k <= to_y; k++) {
				for (int l = from_x; l <= to_x; l++) {
					int dy = i - k;
					int dx = j - l;
					int dist = dy * dy + dx * dx;
					if (dist >= closest_dist) {
						continue;
					}

					const uint8_t *rp2 = &srcptr[(k * width + l) << 2];

					if (rp2[3] < alpha_threshold) {
						continue;
					}

					closest_dist = dist;
					closest_color[0] = rp2[0];
					closest_color[1] = rp2[1];
					closest_color[2] = rp2[2];
				}
			}

			if (closest_dist != max_dist) {
				wptr[0] = closest_color[0];
				wptr[1] = closest_color[1];
				wptr[2] = closest_color[2];
			}
		}
	}
}

String Image::get_format_name(Format p_format) {
	ERR_FAIL_INDEX_V(p_format, FORMAT_MAX, String());
	return format_names[p_format];
}

Error Image::load_png_from_buffer(const Vector<uint8_t> &p_array) {
	return _load_from_buffer(p_array, _png_mem_loader_func);
}

Error Image::load_jpg_from_buffer(const Vector<uint8_t> &p_array) {
	return _load_from_buffer(p_array, _jpg_mem_loader_func);
}

Error Image::load_webp_from_buffer(const Vector<uint8_t> &p_array) {
	return _load_from_buffer(p_array, _webp_mem_loader_func);
}

Error Image::load_tga_from_buffer(const Vector<uint8_t> &p_array) {
	ERR_FAIL_NULL_V_MSG(
			_tga_mem_loader_func,
			ERR_UNAVAILABLE,
			"The TGA module isn't enabled. Recompile the Godot editor or export template binary with the `module_tga_enabled=yes` SCons option.");
	return _load_from_buffer(p_array, _tga_mem_loader_func);
}

Error Image::load_bmp_from_buffer(const Vector<uint8_t> &p_array) {
	ERR_FAIL_NULL_V_MSG(
			_bmp_mem_loader_func,
			ERR_UNAVAILABLE,
			"The BMP module isn't enabled. Recompile the Godot editor or export template binary with the `module_bmp_enabled=yes` SCons option.");
	return _load_from_buffer(p_array, _bmp_mem_loader_func);
}

Error Image::load_svg_from_buffer(const Vector<uint8_t> &p_array, float scale) {
	ERR_FAIL_NULL_V_MSG(
			_svg_scalable_mem_loader_func,
			ERR_UNAVAILABLE,
			"The SVG module isn't enabled. Recompile the Godot editor or export template binary with the `module_svg_enabled=yes` SCons option.");

	int buffer_size = p_array.size();

	ERR_FAIL_COND_V(buffer_size == 0, ERR_INVALID_PARAMETER);

	Ref<Image> image = _svg_scalable_mem_loader_func(p_array.ptr(), buffer_size, scale);
	ERR_FAIL_COND_V(!image.is_valid(), ERR_PARSE_ERROR);

	copy_internals_from(image);

	return OK;
}

Error Image::load_svg_from_string(const String &p_svg_str, float scale) {
	return load_svg_from_buffer(p_svg_str.to_utf8_buffer(), scale);
}

Error Image::load_ktx_from_buffer(const Vector<uint8_t> &p_array) {
	ERR_FAIL_NULL_V_MSG(
			_ktx_mem_loader_func,
			ERR_UNAVAILABLE,
			"The KTX module isn't enabled. Recompile the Godot editor or export template binary with the `module_ktx_enabled=yes` SCons option.");
	return _load_from_buffer(p_array, _ktx_mem_loader_func);
}

void Image::convert_rg_to_ra_rgba8() {
	ERR_FAIL_COND(format != FORMAT_RGBA8);
	ERR_FAIL_COND(!data.size());

	int s = data.size();
	uint8_t *w = data.ptrw();
	for (int i = 0; i < s; i += 4) {
		w[i + 3] = w[i + 1];
		w[i + 1] = 0;
		w[i + 2] = 0;
	}
}

void Image::convert_ra_rgba8_to_rg() {
	ERR_FAIL_COND(format != FORMAT_RGBA8);
	ERR_FAIL_COND(!data.size());

	int s = data.size();
	uint8_t *w = data.ptrw();
	for (int i = 0; i < s; i += 4) {
		w[i + 1] = w[i + 3];
		w[i + 2] = 0;
		w[i + 3] = 255;
	}
}

void Image::convert_rgba8_to_bgra8() {
	ERR_FAIL_COND(format != FORMAT_RGBA8);
	ERR_FAIL_COND(!data.size());

	int s = data.size();
	uint8_t *w = data.ptrw();
	for (int i = 0; i < s; i += 4) {
		uint8_t r = w[i];
		w[i] = w[i + 2]; // Swap R to B
		w[i + 2] = r; // Swap B to R
	}
}

Error Image::_load_from_buffer(const Vector<uint8_t> &p_array, ImageMemLoadFunc p_loader) {
	int buffer_size = p_array.size();

	ERR_FAIL_COND_V(buffer_size == 0, ERR_INVALID_PARAMETER);
	ERR_FAIL_COND_V(!p_loader, ERR_INVALID_PARAMETER);

	const uint8_t *r = p_array.ptr();

	Ref<Image> image = p_loader(r, buffer_size);
	ERR_FAIL_COND_V(!image.is_valid(), ERR_PARSE_ERROR);

	copy_internals_from(image);

	return OK;
}

void Image::average_4_uint8(uint8_t &p_out, const uint8_t &p_a, const uint8_t &p_b, const uint8_t &p_c, const uint8_t &p_d) {
	p_out = static_cast<uint8_t>((p_a + p_b + p_c + p_d + 2) >> 2);
}

void Image::average_4_float(float &p_out, const float &p_a, const float &p_b, const float &p_c, const float &p_d) {
	p_out = (p_a + p_b + p_c + p_d) * 0.25f;
}

void Image::average_4_half(uint16_t &p_out, const uint16_t &p_a, const uint16_t &p_b, const uint16_t &p_c, const uint16_t &p_d) {
	p_out = Math::make_half_float((Math::half_to_float(p_a) + Math::half_to_float(p_b) + Math::half_to_float(p_c) + Math::half_to_float(p_d)) * 0.25f);
}

void Image::average_4_rgbe9995(uint32_t &p_out, const uint32_t &p_a, const uint32_t &p_b, const uint32_t &p_c, const uint32_t &p_d) {
	p_out = ((Color::from_rgbe9995(p_a) + Color::from_rgbe9995(p_b) + Color::from_rgbe9995(p_c) + Color::from_rgbe9995(p_d)) * 0.25f).to_rgbe9995();
}

void Image::renormalize_uint8(uint8_t *p_rgb) {
	Vector3 n(p_rgb[0] / 255.0, p_rgb[1] / 255.0, p_rgb[2] / 255.0);
	n *= 2.0;
	n -= Vector3(1, 1, 1);
	n.normalize();
	n += Vector3(1, 1, 1);
	n *= 0.5;
	n *= 255;
	p_rgb[0] = CLAMP(int(n.x), 0, 255);
	p_rgb[1] = CLAMP(int(n.y), 0, 255);
	p_rgb[2] = CLAMP(int(n.z), 0, 255);
}

void Image::renormalize_float(float *p_rgb) {
	Vector3 n(p_rgb[0], p_rgb[1], p_rgb[2]);
	n.normalize();
	p_rgb[0] = n.x;
	p_rgb[1] = n.y;
	p_rgb[2] = n.z;
}

void Image::renormalize_half(uint16_t *p_rgb) {
	Vector3 n(Math::half_to_float(p_rgb[0]), Math::half_to_float(p_rgb[1]), Math::half_to_float(p_rgb[2]));
	n.normalize();
	p_rgb[0] = Math::make_half_float(n.x);
	p_rgb[1] = Math::make_half_float(n.y);
	p_rgb[2] = Math::make_half_float(n.z);
}

void Image::renormalize_rgbe9995(uint32_t *p_rgb) {
	// Never used
}

Image::Image(const uint8_t *p_mem_png_jpg, int p_len) {
	width = 0;
	height = 0;
	mipmaps = false;
	format = FORMAT_L8;

	if (_png_mem_loader_func) {
		copy_internals_from(_png_mem_loader_func(p_mem_png_jpg, p_len));
	}

	if (is_empty() && _jpg_mem_loader_func) {
		copy_internals_from(_jpg_mem_loader_func(p_mem_png_jpg, p_len));
	}

	if (is_empty() && _webp_mem_loader_func) {
		copy_internals_from(_webp_mem_loader_func(p_mem_png_jpg, p_len));
	}
}

Ref<Resource> Image::duplicate(bool p_subresources) const {
	Ref<Image> copy;
	copy.instantiate();
	copy->_copy_internals_from(*this);
	return copy;
}

void Image::set_as_black() {
	memset(data.ptrw(), 0, data.size());
}

Dictionary Image::compute_image_metrics(const Ref<Image> p_compared_image, bool p_luma_metric) {
	// https://github.com/richgel999/bc7enc_rdo/blob/master/LICENSE
	//
	// This is free and unencumbered software released into the public domain.
	// Anyone is free to copy, modify, publish, use, compile, sell, or distribute this
	// software, either in source code form or as a compiled binary, for any purpose,
	// commercial or non - commercial, and by any means.
	// In jurisdictions that recognize copyright laws, the author or authors of this
	// software dedicate any and all copyright interest in the software to the public
	// domain. We make this dedication for the benefit of the public at large and to
	// the detriment of our heirs and successors. We intend this dedication to be an
	// overt act of relinquishment in perpetuity of all present and future rights to
	// this software under copyright law.
	// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
	// AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
	// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

	Dictionary result;
	result["max"] = INFINITY;
	result["mean"] = INFINITY;
	result["mean_squared"] = INFINITY;
	result["root_mean_squared"] = INFINITY;
	result["peak_snr"] = 0.0f;

	ERR_FAIL_NULL_V(p_compared_image, result);
	Error err = OK;
	Ref<Image> compared_image = duplicate(true);
	if (compared_image->is_compressed()) {
		err = compared_image->decompress();
	}
	ERR_FAIL_COND_V(err != OK, result);
	Ref<Image> source_image = p_compared_image->duplicate(true);
	if (source_image->is_compressed()) {
		err = source_image->decompress();
	}
	ERR_FAIL_COND_V(err != OK, result);

	ERR_FAIL_COND_V(err != OK, result);

	ERR_FAIL_COND_V_MSG((compared_image->get_format() >= Image::FORMAT_RH) && (compared_image->get_format() <= Image::FORMAT_RGBE9995), result, "Metrics on HDR images are not supported.");
	ERR_FAIL_COND_V_MSG((source_image->get_format() >= Image::FORMAT_RH) && (source_image->get_format() <= Image::FORMAT_RGBE9995), result, "Metrics on HDR images are not supported.");

	double image_metric_max, image_metric_mean, image_metric_mean_squared, image_metric_root_mean_squared, image_metric_peak_snr = 0.0;
	const bool average_component_error = true;

	const uint32_t w = MIN(compared_image->get_width(), source_image->get_width());
	const uint32_t h = MIN(compared_image->get_height(), source_image->get_height());

	// Histogram approach originally due to Charles Bloom.
	double hist[256];
	memset(hist, 0, sizeof(hist));

	for (uint32_t y = 0; y < h; y++) {
		for (uint32_t x = 0; x < w; x++) {
			const Color color_a = compared_image->get_pixel(x, y);

			const Color color_b = source_image->get_pixel(x, y);

			if (!p_luma_metric) {
				ERR_FAIL_COND_V_MSG(color_a.r > 1.0f, Dictionary(), "Can't compare HDR colors.");
				ERR_FAIL_COND_V_MSG(color_b.r > 1.0f, Dictionary(), "Can't compare HDR colors.");
				hist[Math::abs(color_a.get_r8() - color_b.get_r8())]++;
				ERR_FAIL_COND_V_MSG(color_a.g > 1.0f, Dictionary(), "Can't compare HDR colors.");
				ERR_FAIL_COND_V_MSG(color_b.g > 1.0f, Dictionary(), "Can't compare HDR colors.");
				hist[Math::abs(color_a.get_g8() - color_b.get_g8())]++;
				ERR_FAIL_COND_V_MSG(color_a.b > 1.0f, Dictionary(), "Can't compare HDR colors.");
				ERR_FAIL_COND_V_MSG(color_b.b > 1.0f, Dictionary(), "Can't compare HDR colors.");
				hist[Math::abs(color_a.get_b8() - color_b.get_b8())]++;
				ERR_FAIL_COND_V_MSG(color_a.a > 1.0f, Dictionary(), "Can't compare HDR colors.");
				ERR_FAIL_COND_V_MSG(color_b.a > 1.0f, Dictionary(), "Can't compare HDR colors.");
				hist[Math::abs(color_a.get_a8() - color_b.get_a8())]++;
			} else {
				ERR_FAIL_COND_V_MSG(color_a.r > 1.0f, Dictionary(), "Can't compare HDR colors.");
				ERR_FAIL_COND_V_MSG(color_b.r > 1.0f, Dictionary(), "Can't compare HDR colors.");
				// REC709 weightings
				int luma_a = (13938U * color_a.get_r8() + 46869U * color_a.get_g8() + 4729U * color_a.get_b8() + 32768U) >> 16U;
				int luma_b = (13938U * color_b.get_r8() + 46869U * color_b.get_g8() + 4729U * color_b.get_b8() + 32768U) >> 16U;
				hist[Math::abs(luma_a - luma_b)]++;
			}
		}
	}

	image_metric_max = 0;
	double sum = 0.0f, sum2 = 0.0f;
	for (uint32_t i = 0; i < 256; i++) {
		if (!hist[i]) {
			continue;
		}

		image_metric_max = MAX(image_metric_max, i);

		double x = i * hist[i];

		sum += x;
		sum2 += i * x;
	}

	// See http://richg42.blogspot.com/2016/09/how-to-compute-psnr-from-old-berkeley.html
	double total_values = w * h;

	if (average_component_error) {
		total_values *= 4;
	}

	image_metric_mean = CLAMP(sum / total_values, 0.0f, 255.0f);
	image_metric_mean_squared = CLAMP(sum2 / total_values, 0.0f, 255.0f * 255.0f);

	image_metric_root_mean_squared = sqrt(image_metric_mean_squared);

	if (!image_metric_root_mean_squared) {
		image_metric_peak_snr = 1e+10f;
	} else {
		image_metric_peak_snr = CLAMP(log10(255.0f / image_metric_root_mean_squared) * 20.0f, 0.0f, 500.0f);
	}
	result["max"] = image_metric_max;
	result["mean"] = image_metric_mean;
	result["mean_squared"] = image_metric_mean_squared;
	result["root_mean_squared"] = image_metric_root_mean_squared;
	result["peak_snr"] = image_metric_peak_snr;
	return result;
}