#[compute]
#version 450
#VERSION_DEFINES
layout(local_size_x = 8, local_size_y = 8, local_size_z = 1) in;
#ifdef MODE_RESOLVE_DEPTH
layout(set = 0, binding = 0) uniform sampler2DMS source_depth;
layout(r32f, set = 1, binding = 0) uniform restrict writeonly image2D dest_depth;
#endif
#ifdef MODE_RESOLVE_GI
layout(set = 0, binding = 0) uniform sampler2DMS source_depth;
layout(set = 0, binding = 1) uniform sampler2DMS source_normal_roughness;
layout(r32f, set = 1, binding = 0) uniform restrict writeonly image2D dest_depth;
layout(rgba8, set = 1, binding = 1) uniform restrict writeonly image2D dest_normal_roughness;
#ifdef VOXEL_GI_RESOLVE
layout(set = 2, binding = 0) uniform usampler2DMS source_voxel_gi;
layout(rg8ui, set = 3, binding = 0) uniform restrict writeonly uimage2D dest_voxel_gi;
#endif
#endif
layout(push_constant, std430) uniform Params {
ivec2 screen_size;
int sample_count;
uint pad;
}
params;
void main() {
// Pixel being shaded
ivec2 pos = ivec2(gl_GlobalInvocationID.xy);
if (any(greaterThanEqual(pos, params.screen_size))) { //too large, do nothing
return;
}
#ifdef MODE_RESOLVE_DEPTH
float depth_avg = 0.0;
for (int i = 0; i < params.sample_count; i++) {
depth_avg += texelFetch(source_depth, pos, i).r;
}
depth_avg /= float(params.sample_count);
imageStore(dest_depth, pos, vec4(depth_avg));
#endif
#ifdef MODE_RESOLVE_GI
float best_depth = 1e20;
vec4 best_normal_roughness = vec4(0.0);
#ifdef VOXEL_GI_RESOLVE
uvec2 best_voxel_gi;
#endif
#if 0
for(int i=0;i<params.sample_count;i++) {
float depth = texelFetch(source_depth,pos,i).r;
if (depth < best_depth) { //use the depth closest to camera
best_depth = depth;
best_normal_roughness = texelFetch(source_normal_roughness,pos,i);
#ifdef VOXEL_GI_RESOLVE
best_voxel_gi = texelFetch(source_voxel_gi,pos,i).rg;
#endif
}
}
#else
#if 1
vec4 group1;
vec4 group2;
vec4 group3;
vec4 group4;
int best_index = 0;
//2X
group1.x = texelFetch(source_depth, pos, 0).r;
group1.y = texelFetch(source_depth, pos, 1).r;
//4X
if (params.sample_count >= 4) {
group1.z = texelFetch(source_depth, pos, 2).r;
group1.w = texelFetch(source_depth, pos, 3).r;
}
//8X
if (params.sample_count >= 8) {
group2.x = texelFetch(source_depth, pos, 4).r;
group2.y = texelFetch(source_depth, pos, 5).r;
group2.z = texelFetch(source_depth, pos, 6).r;
group2.w = texelFetch(source_depth, pos, 7).r;
}
//16X
if (params.sample_count >= 16) {
group3.x = texelFetch(source_depth, pos, 8).r;
group3.y = texelFetch(source_depth, pos, 9).r;
group3.z = texelFetch(source_depth, pos, 10).r;
group3.w = texelFetch(source_depth, pos, 11).r;
group4.x = texelFetch(source_depth, pos, 12).r;
group4.y = texelFetch(source_depth, pos, 13).r;
group4.z = texelFetch(source_depth, pos, 14).r;
group4.w = texelFetch(source_depth, pos, 15).r;
}
if (params.sample_count == 2) {
best_index = (pos.x & 1) ^ ((pos.y >> 1) & 1); //not much can be done here
} else if (params.sample_count == 4) {
vec4 freq = vec4(equal(group1, vec4(group1.x)));
freq += vec4(equal(group1, vec4(group1.y)));
freq += vec4(equal(group1, vec4(group1.z)));
freq += vec4(equal(group1, vec4(group1.w)));
float min_f = freq.x;
best_index = 0;
if (freq.y < min_f) {
best_index = 1;
min_f = freq.y;
}
if (freq.z < min_f) {
best_index = 2;
min_f = freq.z;
}
if (freq.w < min_f) {
best_index = 3;
}
} else if (params.sample_count == 8) {
vec4 freq0 = vec4(equal(group1, vec4(group1.x)));
vec4 freq1 = vec4(equal(group2, vec4(group1.x)));
freq0 += vec4(equal(group1, vec4(group1.y)));
freq1 += vec4(equal(group2, vec4(group1.y)));
freq0 += vec4(equal(group1, vec4(group1.z)));
freq1 += vec4(equal(group2, vec4(group1.z)));
freq0 += vec4(equal(group1, vec4(group1.w)));
freq1 += vec4(equal(group2, vec4(group1.w)));
freq0 += vec4(equal(group1, vec4(group2.x)));
freq1 += vec4(equal(group2, vec4(group2.x)));
freq0 += vec4(equal(group1, vec4(group2.y)));
freq1 += vec4(equal(group2, vec4(group2.y)));
freq0 += vec4(equal(group1, vec4(group2.z)));
freq1 += vec4(equal(group2, vec4(group2.z)));
freq0 += vec4(equal(group1, vec4(group2.w)));
freq1 += vec4(equal(group2, vec4(group2.w)));
float min_f0 = freq0.x;
int best_index0 = 0;
if (freq0.y < min_f0) {
best_index0 = 1;
min_f0 = freq0.y;
}
if (freq0.z < min_f0) {
best_index0 = 2;
min_f0 = freq0.z;
}
if (freq0.w < min_f0) {
best_index0 = 3;
min_f0 = freq0.w;
}
float min_f1 = freq1.x;
int best_index1 = 4;
if (freq1.y < min_f1) {
best_index1 = 5;
min_f1 = freq1.y;
}
if (freq1.z < min_f1) {
best_index1 = 6;
min_f1 = freq1.z;
}
if (freq1.w < min_f1) {
best_index1 = 7;
min_f1 = freq1.w;
}
best_index = mix(best_index0, best_index1, min_f0 < min_f1);
}
#else
float depths[16];
int depth_indices[16];
int depth_amount[16];
int depth_count = 0;
for (int i = 0; i < params.sample_count; i++) {
float depth = texelFetch(source_depth, pos, i).r;
int depth_index = -1;
for (int j = 0; j < depth_count; j++) {
if (abs(depths[j] - depth) < 0.000001) {
depth_index = j;
break;
}
}
if (depth_index == -1) {
depths[depth_count] = depth;
depth_indices[depth_count] = i;
depth_amount[depth_count] = 1;
depth_count += 1;
} else {
depth_amount[depth_index] += 1;
}
}
int depth_least = 0xFFFF;
int best_index = 0;
for (int j = 0; j < depth_count; j++) {
if (depth_amount[j] < depth_least) {
best_index = depth_indices[j];
depth_least = depth_amount[j];
}
}
#endif
best_depth = texelFetch(source_depth, pos, best_index).r;
best_normal_roughness = texelFetch(source_normal_roughness, pos, best_index);
#ifdef VOXEL_GI_RESOLVE
best_voxel_gi = texelFetch(source_voxel_gi, pos, best_index).rg;
#endif
#endif
imageStore(dest_depth, pos, vec4(best_depth));
imageStore(dest_normal_roughness, pos, vec4(best_normal_roughness));
#ifdef VOXEL_GI_RESOLVE
imageStore(dest_voxel_gi, pos, uvec4(best_voxel_gi, 0, 0));
#endif
#endif
}