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
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
/* clang-format off */
[vertex]
#version 450
VERSION_DEFINES
layout(location = 0) out vec2 uv_interp;
/* clang-format on */
void main() {
vec2 base_arr[4] = vec2[](vec2(0.0, 0.0), vec2(0.0, 1.0), vec2(1.0, 1.0), vec2(1.0, 0.0));
uv_interp = base_arr[gl_VertexIndex];
gl_Position = vec4(uv_interp * 2.0 - 1.0, 0.0, 1.0);
}
/* clang-format off */
[fragment]
#version 450
VERSION_DEFINES
layout(location = 0) in vec2 uv_interp;
/* clang-format on */
#ifdef MODE_CUBE_TO_DP
layout(set = 0, binding = 0) uniform samplerCube source_cube;
layout(push_constant, binding = 0, std430) uniform Params {
float bias;
float z_far;
float z_near;
bool z_flip;
}
params;
layout(location = 0) out float depth_buffer;
#endif
void main() {
#ifdef MODE_CUBE_TO_DP
vec3 normal = vec3(uv_interp * 2.0 - 1.0, 0.0);
normal.z = 0.5 - 0.5 * ((normal.x * normal.x) + (normal.y * normal.y));
normal = normalize(normal);
normal.y = -normal.y; //needs to be flipped to match projection matrix
if (!params.z_flip) {
normal.z = -normal.z;
}
float depth = texture(source_cube, normal).r;
// absolute values for direction cosines, bigger value equals closer to basis axis
vec3 unorm = abs(normal);
if ((unorm.x >= unorm.y) && (unorm.x >= unorm.z)) {
// x code
unorm = normal.x > 0.0 ? vec3(1.0, 0.0, 0.0) : vec3(-1.0, 0.0, 0.0);
} else if ((unorm.y > unorm.x) && (unorm.y >= unorm.z)) {
// y code
unorm = normal.y > 0.0 ? vec3(0.0, 1.0, 0.0) : vec3(0.0, -1.0, 0.0);
} else if ((unorm.z > unorm.x) && (unorm.z > unorm.y)) {
// z code
unorm = normal.z > 0.0 ? vec3(0.0, 0.0, 1.0) : vec3(0.0, 0.0, -1.0);
} else {
// oh-no we messed up code
// has to be
unorm = vec3(1.0, 0.0, 0.0);
}
float depth_fix = 1.0 / dot(normal, unorm);
depth = 2.0 * depth - 1.0;
float linear_depth = 2.0 * params.z_near * params.z_far / (params.z_far + params.z_near - depth * (params.z_far - params.z_near));
depth_buffer = (linear_depth * depth_fix + params.bias) / params.z_far;
#endif
}
|