virtualx-engine/drivers/gles3/shaders/particles_copy.glsl
clayjohn 9ce57050a5 Add GPUParticles to the OpenGL3 renderer.
This includes collision (2D SDF, Box, Sphere, Heightmap),
attraction (Box, Sphere), and all sorting modes.

This does not include 3D SDF collisions, trails, or
manual emission.
2022-11-14 23:28:25 -08:00

122 lines
3.2 KiB
GLSL

/* clang-format off */
#[modes]
mode_default =
#[specializations]
MODE_3D = false
#[vertex]
#include "stdlib_inc.glsl"
// ParticleData
layout(location = 0) in highp vec4 color;
layout(location = 1) in highp vec4 velocity_flags;
layout(location = 2) in highp vec4 custom;
layout(location = 3) in highp vec4 xform_1;
layout(location = 4) in highp vec4 xform_2;
#ifdef MODE_3D
layout(location = 5) in highp vec4 xform_3;
#endif
/* clang-format on */
out highp vec4 out_xform_1; //tfb:
out highp vec4 out_xform_2; //tfb:
#ifdef MODE_3D
out highp vec4 out_xform_3; //tfb:MODE_3D
#endif
flat out highp uvec4 instance_color_custom_data; //tfb:
uniform lowp vec3 sort_direction;
uniform highp float frame_remainder;
uniform highp vec3 align_up;
uniform highp uint align_mode;
uniform highp mat4 inv_emission_transform;
#define TRANSFORM_ALIGN_DISABLED uint(0)
#define TRANSFORM_ALIGN_Z_BILLBOARD uint(1)
#define TRANSFORM_ALIGN_Y_TO_VELOCITY uint(2)
#define TRANSFORM_ALIGN_Z_BILLBOARD_Y_TO_VELOCITY uint(3)
#define PARTICLE_FLAG_ACTIVE uint(1)
void main() {
mat4 txform = mat4(vec4(0.0), vec4(0.0), vec4(0.0), vec4(0.0)); // zero scale, becomes invisible.
if (bool(floatBitsToUint(velocity_flags.w) & PARTICLE_FLAG_ACTIVE)) {
#ifdef MODE_3D
txform = transpose(mat4(xform_1, xform_2, xform_3, vec4(0.0, 0.0, 0.0, 1.0)));
#else
txform = transpose(mat4(xform_1, xform_2, vec4(0.0, 0.0, 1.0, 0.0), vec4(0.0, 0.0, 0.0, 1.0)));
#endif
switch (align_mode) {
case TRANSFORM_ALIGN_DISABLED: {
} break; //nothing
case TRANSFORM_ALIGN_Z_BILLBOARD: {
mat3 local = mat3(normalize(cross(align_up, sort_direction)), align_up, sort_direction);
local = local * mat3(txform);
txform[0].xyz = local[0];
txform[1].xyz = local[1];
txform[2].xyz = local[2];
} break;
case TRANSFORM_ALIGN_Y_TO_VELOCITY: {
vec3 v = velocity_flags.xyz;
float s = (length(txform[0]) + length(txform[1]) + length(txform[2])) / 3.0;
if (length(v) > 0.0) {
txform[1].xyz = normalize(v);
} else {
txform[1].xyz = normalize(txform[1].xyz);
}
txform[0].xyz = normalize(cross(txform[1].xyz, txform[2].xyz));
txform[2].xyz = vec3(0.0, 0.0, 1.0) * s;
txform[0].xyz *= s;
txform[1].xyz *= s;
} break;
case TRANSFORM_ALIGN_Z_BILLBOARD_Y_TO_VELOCITY: {
vec3 sv = velocity_flags.xyz - sort_direction * dot(sort_direction, velocity_flags.xyz); //screen velocity
float s = (length(txform[0]) + length(txform[1]) + length(txform[2])) / 3.0;
if (length(sv) == 0.0) {
sv = align_up;
}
sv = normalize(sv);
txform[0].xyz = normalize(cross(sv, sort_direction)) * s;
txform[1].xyz = sv * s;
txform[2].xyz = sort_direction * s;
} break;
}
txform[3].xyz += velocity_flags.xyz * frame_remainder;
#ifndef MODE_3D
// In global mode, bring 2D particles to local coordinates
// as they will be drawn with the node position as origin.
txform = inv_emission_transform * txform;
#endif
txform = transpose(txform);
}
instance_color_custom_data = uvec4(packHalf2x16(color.xy), packHalf2x16(color.zw), packHalf2x16(custom.xy), packHalf2x16(custom.zw));
out_xform_1 = txform[0];
out_xform_2 = txform[1];
#ifdef MODE_3D
out_xform_3 = txform[2];
#endif
}
/* clang-format off */
#[fragment]
void main() {
}
/* clang-format on */