virtualx-engine/thirdparty/basis_universal/basisu_pvrtc1_4.h

363 lines
9.5 KiB
C++

// basisu_pvrtc1_4.cpp
// Copyright (C) 2019 Binomial LLC. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#pragma once
#include "basisu_gpu_texture.h"
namespace basisu
{
enum
{
PVRTC2_MIN_WIDTH = 16,
PVRTC2_MIN_HEIGHT = 8,
PVRTC4_MIN_WIDTH = 8,
PVRTC4_MIN_HEIGHT = 8
};
struct pvrtc4_block
{
uint32_t m_modulation;
uint32_t m_endpoints;
pvrtc4_block() : m_modulation(0), m_endpoints(0) { }
inline bool operator== (const pvrtc4_block& rhs) const
{
return (m_modulation == rhs.m_modulation) && (m_endpoints == rhs.m_endpoints);
}
inline void clear()
{
m_modulation = 0;
m_endpoints = 0;
}
inline bool get_block_uses_transparent_modulation() const
{
return (m_endpoints & 1) != 0;
}
inline bool is_endpoint_opaque(uint32_t endpoint_index) const
{
static const uint32_t s_bitmasks[2] = { 0x8000U, 0x80000000U };
return (m_endpoints & s_bitmasks[open_range_check(endpoint_index, 2U)]) != 0;
}
// Returns raw endpoint or 8888
color_rgba get_endpoint(uint32_t endpoint_index, bool unpack) const;
color_rgba get_endpoint_5554(uint32_t endpoint_index) const;
static uint32_t get_component_precision_in_bits(uint32_t c, uint32_t endpoint_index, bool opaque_endpoint)
{
static const uint32_t s_comp_prec[4][4] =
{
// R0 G0 B0 A0 R1 G1 B1 A1
{ 4, 4, 3, 3 }, { 4, 4, 4, 3 }, // transparent endpoint
{ 5, 5, 4, 0 }, { 5, 5, 5, 0 } // opaque endpoint
};
return s_comp_prec[open_range_check(endpoint_index, 2U) + (opaque_endpoint * 2)][open_range_check(c, 4U)];
}
static color_rgba get_color_precision_in_bits(uint32_t endpoint_index, bool opaque_endpoint)
{
static const color_rgba s_color_prec[4] =
{
color_rgba(4, 4, 3, 3), color_rgba(4, 4, 4, 3), // transparent endpoint
color_rgba(5, 5, 4, 0), color_rgba(5, 5, 5, 0) // opaque endpoint
};
return s_color_prec[open_range_check(endpoint_index, 2U) + (opaque_endpoint * 2)];
}
inline uint32_t get_modulation(uint32_t x, uint32_t y) const
{
assert((x < 4) && (y < 4));
return (m_modulation >> ((y * 4 + x) * 2)) & 3;
}
// Scaled by 8
inline const uint32_t* get_scaled_modulation_values(bool block_uses_transparent_modulation) const
{
static const uint32_t s_block_scales[2][4] = { { 0, 3, 5, 8 }, { 0, 4, 4, 8 } };
return s_block_scales[block_uses_transparent_modulation];
}
// Scaled by 8
inline uint32_t get_scaled_modulation(uint32_t x, uint32_t y) const
{
return get_scaled_modulation_values(get_block_uses_transparent_modulation())[get_modulation(x, y)];
}
inline void byte_swap()
{
m_modulation = byteswap32(m_modulation);
m_endpoints = byteswap32(m_endpoints);
}
// opaque endpoints: 554, 555
// transparent endpoints: 3443 or 3444
inline void set_endpoint_raw(uint32_t endpoint_index, const color_rgba& c, bool opaque_endpoint)
{
assert(endpoint_index < 2);
const uint32_t m = m_endpoints & 1;
uint32_t r = c[0], g = c[1], b = c[2], a = c[3];
uint32_t packed;
if (opaque_endpoint)
{
if (!endpoint_index)
{
// 554
// 1RRRRRGGGGGBBBBM
assert((r < 32) && (g < 32) && (b < 16));
packed = 0x8000 | (r << 10) | (g << 5) | (b << 1) | m;
}
else
{
// 555
// 1RRRRRGGGGGBBBBB
assert((r < 32) && (g < 32) && (b < 32));
packed = 0x8000 | (r << 10) | (g << 5) | b;
}
}
else
{
if (!endpoint_index)
{
// 3443
// 0AAA RRRR GGGG BBBM
assert((r < 16) && (g < 16) && (b < 8) && (a < 8));
packed = (a << 12) | (r << 8) | (g << 4) | (b << 1) | m;
}
else
{
// 3444
// 0AAA RRRR GGGG BBBB
assert((r < 16) && (g < 16) && (b < 16) && (a < 8));
packed = (a << 12) | (r << 8) | (g << 4) | b;
}
}
assert(packed <= 0xFFFF);
if (endpoint_index)
m_endpoints = (m_endpoints & 0xFFFFU) | (packed << 16);
else
m_endpoints = (m_endpoints & 0xFFFF0000U) | packed;
}
};
typedef vector2D<pvrtc4_block> pvrtc4_block_vector2D;
uint32_t pvrtc4_swizzle_uv(uint32_t XSize, uint32_t YSize, uint32_t XPos, uint32_t YPos);
class pvrtc4_image
{
public:
inline pvrtc4_image() :
m_width(0), m_height(0), m_block_width(0), m_block_height(0), m_uses_alpha(false)
{
}
inline pvrtc4_image(uint32_t width, uint32_t height) :
m_width(0), m_height(0), m_block_width(0), m_block_height(0), m_uses_alpha(false)
{
resize(width, height);
}
inline void clear()
{
m_width = 0;
m_height = 0;
m_block_width = 0;
m_block_height = 0;
m_blocks.clear();
m_uses_alpha = false;
}
inline void resize(uint32_t width, uint32_t height)
{
if ((width == m_width) && (height == m_height))
return;
m_width = width;
m_height = height;
m_block_width = (width + 3) >> 2;
m_block_height = (height + 3) >> 2;
m_blocks.resize(m_block_width, m_block_height);
}
inline uint32_t get_width() const { return m_width; }
inline uint32_t get_height() const { return m_height; }
inline uint32_t get_block_width() const { return m_block_width; }
inline uint32_t get_block_height() const { return m_block_height; }
inline const pvrtc4_block_vector2D &get_blocks() const { return m_blocks; }
inline pvrtc4_block_vector2D &get_blocks() { return m_blocks; }
inline uint32_t get_total_blocks() const { return m_block_width * m_block_height; }
inline bool get_uses_alpha() const { return m_uses_alpha; }
inline void set_uses_alpha(bool uses_alpha) { m_uses_alpha = uses_alpha; }
inline bool are_blocks_equal(const pvrtc4_image& rhs) const
{
return m_blocks == rhs.m_blocks;
}
inline void set_to_black()
{
memset(m_blocks.get_ptr(), 0, m_blocks.size_in_bytes());
}
inline bool get_block_uses_transparent_modulation(uint32_t bx, uint32_t by) const
{
return m_blocks(bx, by).get_block_uses_transparent_modulation();
}
inline bool is_endpoint_opaque(uint32_t bx, uint32_t by, uint32_t endpoint_index) const
{
return m_blocks(bx, by).is_endpoint_opaque(endpoint_index);
}
color_rgba get_endpoint(uint32_t bx, uint32_t by, uint32_t endpoint_index, bool unpack) const
{
assert((bx < m_block_width) && (by < m_block_height));
return m_blocks(bx, by).get_endpoint(endpoint_index, unpack);
}
inline uint32_t get_modulation(uint32_t x, uint32_t y) const
{
assert((x < m_width) && (y < m_height));
return m_blocks(x >> 2, y >> 2).get_modulation(x & 3, y & 3);
}
// Returns true if the block uses transparent modulation.
bool get_interpolated_colors(uint32_t x, uint32_t y, color_rgba* pColors) const;
color_rgba get_pixel(uint32_t x, uint32_t y, uint32_t m) const;
inline color_rgba get_pixel(uint32_t x, uint32_t y) const
{
assert((x < m_width) && (y < m_height));
return get_pixel(x, y, m_blocks(x >> 2, y >> 2).get_modulation(x & 3, y & 3));
}
void deswizzle()
{
pvrtc4_block_vector2D temp(m_blocks);
for (uint32_t y = 0; y < m_block_height; y++)
for (uint32_t x = 0; x < m_block_width; x++)
m_blocks(x, y) = temp[pvrtc4_swizzle_uv(m_block_width, m_block_height, x, y)];
}
void swizzle()
{
pvrtc4_block_vector2D temp(m_blocks);
for (uint32_t y = 0; y < m_block_height; y++)
for (uint32_t x = 0; x < m_block_width; x++)
m_blocks[pvrtc4_swizzle_uv(m_block_width, m_block_height, x, y)] = temp(x, y);
}
void unpack_all_pixels(image& img) const
{
img.crop(m_width, m_height);
for (uint32_t y = 0; y < m_height; y++)
for (uint32_t x = 0; x < m_width; x++)
img(x, y) = get_pixel(x, y);
}
void unpack_block(image &dst, uint32_t block_x, uint32_t block_y)
{
for (uint32_t y = 0; y < 4; y++)
for (uint32_t x = 0; x < 4; x++)
dst(x, y) = get_pixel(block_x * 4 + x, block_y * 4 + y);
}
inline int wrap_x(int x) const
{
return posmod(x, m_width);
}
inline int wrap_y(int y) const
{
return posmod(y, m_height);
}
inline int wrap_block_x(int bx) const
{
return posmod(bx, m_block_width);
}
inline int wrap_block_y(int by) const
{
return posmod(by, m_block_height);
}
inline vec2F get_interpolation_factors(uint32_t x, uint32_t y) const
{
// 0 1 2 3
// 2 3 0 1
// .5 .75 0 .25
static const float s_interp[4] = { 2, 3, 0, 1 };
return vec2F(s_interp[x & 3], s_interp[y & 3]);
}
inline color_rgba interpolate(int x, int y,
const color_rgba& p, const color_rgba& q,
const color_rgba& r, const color_rgba& s) const
{
static const int s_interp[4] = { 2, 3, 0, 1 };
const int u_interp = s_interp[x & 3];
const int v_interp = s_interp[y & 3];
color_rgba result;
for (uint32_t c = 0; c < 4; c++)
{
int t = p[c] * 4 + u_interp * ((int)q[c] - (int)p[c]);
int b = r[c] * 4 + u_interp * ((int)s[c] - (int)r[c]);
int v = t * 4 + v_interp * (b - t);
if (c < 3)
{
v >>= 1;
v += (v >> 5);
}
else
{
v += (v >> 4);
}
assert((v >= 0) && (v < 256));
result[c] = static_cast<uint8_t>(v);
}
return result;
}
uint32_t m_width, m_height;
pvrtc4_block_vector2D m_blocks;
uint32_t m_block_width, m_block_height;
bool m_uses_alpha;
};
} // namespace basisu