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
|
/**
* This shader only compute maximum horizon angles for each directions.
* The final integration is done at the resolve stage with the shading normal.
**/
uniform float rotationOffset;
out vec4 FragColor;
#ifdef DEBUG_AO
uniform sampler2D normalBuffer;
void main()
{
vec2 texel_size = 1.0 / vec2(textureSize(depthBuffer, 0)).xy;
vec2 uvs = saturate(gl_FragCoord.xy * texel_size);
float depth = textureLod(depthBuffer, uvs, 0.0).r;
vec3 viewPosition = get_view_space_from_depth(uvs, depth);
vec3 V = viewCameraVec;
vec3 normal = normal_decode(texture(normalBuffer, uvs).rg, V);
vec3 bent_normal;
float visibility;
vec4 noise = texelfetch_noise_tex(gl_FragCoord.xy);
gtao_deferred(normal, noise, depth, visibility, bent_normal);
/* Handle Background case. Prevent artifact due to uncleared Horizon Render Target. */
FragColor = vec4((depth == 1.0) ? 0.0 : visibility);
}
#else
#ifdef LAYERED_DEPTH
uniform sampler2DArray depthBufferLayered;
uniform int layer;
# define gtao_depthBuffer depthBufferLayered
# define gtao_textureLod(a, b, c) textureLod(a, vec3(b, layer), c)
#else
# define gtao_depthBuffer depthBuffer
# define gtao_textureLod(a, b, c) textureLod(a, b, c)
#endif
void main()
{
vec2 uvs = saturate(gl_FragCoord.xy / vec2(textureSize(gtao_depthBuffer, 0).xy));
float depth = gtao_textureLod(gtao_depthBuffer, uvs, 0.0).r;
if (depth == 1.0) {
/* Do not trace for background */
FragColor = vec4(0.0);
return;
}
/* Avoid self shadowing. */
depth = saturate(depth - 3e-6); /* Tweaked for 24bit depth buffer. */
vec3 viewPosition = get_view_space_from_depth(uvs, depth);
vec4 noise = texelfetch_noise_tex(gl_FragCoord.xy);
vec2 max_dir = get_max_dir(viewPosition.z);
vec4 dirs;
dirs.xy = get_ao_dir(noise.x * 0.5);
dirs.zw = get_ao_dir(noise.x * 0.5 + 0.5);
/* Search in 4 directions. */
FragColor.xy = search_horizon_sweep(dirs.xy, viewPosition, uvs, noise.y, max_dir);
FragColor.zw = search_horizon_sweep(dirs.zw, viewPosition, uvs, noise.y, max_dir);
/* Resize output for integer texture. */
FragColor = pack_horizons(FragColor);
}
#endif
|
