1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
#version 450
#define LIST_END ~0x0
#define SORT_MAX 32
layout (location = 0) out vec4 color;
layout(binding = 0) uniform mvp {
mat4 model;
mat4 view;
mat4 proj;
uint count;
} ubo;
layout(binding = 1) buffer fragment_buffer {
uvec3 fragments[];
};
layout(binding = 2, r32ui) uniform uimage2D head;
layout(binding = 3) buffer counter {
int data;
};
vec4 blend_colors(uint packed_color, vec4 dst_color) {
const vec4 src_color = unpackUnorm4x8(packed_color);
return vec4(mix(dst_color.rgb, src_color.rgb, src_color.a), dst_color.a * (1.0f - src_color.a));
}
void main() {
color = vec4(0, 0, 0, 1);
uint idx = imageLoad(head, ivec2(gl_FragCoord.xy)).r;
imageStore(head, ivec2(gl_FragCoord.xy), ivec4(LIST_END, 0, 0, 0));
uvec2 sorted[SORT_MAX];
uint sorted_count = 0;
// TODO: use a proper struct
while (idx != LIST_END) {
const uvec3 fragment = fragments[idx];
idx = fragment.x;
if (sorted_count < SORT_MAX) {
uint i = sorted_count;
for(; i > 0 && fragment.z > sorted[i - 1].y; i--) {
sorted[i] = sorted[i - 1];
}
sorted[i] = fragment.yz;
sorted_count++;
} else if (fragment.z > sorted[0].y) {
color = blend_colors(sorted[0].x, color);
uint i = 0;
for (; i < SORT_MAX - 1 && fragment.z < sorted[i + 1].y; i++) {
sorted[i] = sorted[i + 1];
}
sorted[i] = fragment.yz;
} else {
color = blend_colors(fragment.y, color);
}
}
for (int i = 0; i < sorted_count; i++) {
color = blend_colors(sorted[i].x, color);
}
color.a = 1.0f - color.a;
}
|