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
87
88
89
90
91
92
93
94
95
96
|
#import "Common/ShaderLib/MultiSample.glsllib"
uniform COLORTEXTURE m_Texture;
uniform DEPTHTEXTURE m_DepthTexture;
uniform vec2 g_Resolution;
uniform vec2 m_FrustumNearFar;
uniform sampler2D m_Normals;
uniform sampler2D m_RandomMap;
uniform vec3 m_FrustumCorner;
uniform float m_SampleRadius;
uniform float m_Intensity;
uniform float m_Scale;
uniform float m_Bias;
uniform vec2[4] m_Samples;
in vec2 texCoord;
float depthv;
vec3 getPosition(in vec2 uv){
//Reconstruction from depth
depthv =getDepth(m_DepthTexture,uv).r;
float depth= (2.0 * m_FrustumNearFar.x) / (m_FrustumNearFar.y + m_FrustumNearFar.x - depthv* (m_FrustumNearFar.y-m_FrustumNearFar.x));
//one frustum corner method
float x = mix(-m_FrustumCorner.x, m_FrustumCorner.x, uv.x);
float y = mix(-m_FrustumCorner.y, m_FrustumCorner.y, uv.y);
return depth* vec3(x, y, m_FrustumCorner.z);
}
vec3 getNormal(in vec2 uv){
return normalize(texture2D(m_Normals, uv).xyz * 2.0 - 1.0);
}
vec2 getRandom(in vec2 uv){
//float rand=(fract(uv.x*(g_Resolution.x/2.0))*0.25)+(fract(uv.y*(g_Resolution.y/2.0))*0.5);
vec4 rand=texture2D(m_RandomMap,g_Resolution * uv / 128.0 * 3.0)*2.0 -1.0;
return normalize(rand.xy);
}
float doAmbientOcclusion(in vec2 tc, in vec3 pos, in vec3 norm){
vec3 diff = getPosition(tc)- pos;
vec3 v = normalize(diff);
float d = length(diff) * m_Scale;
return max(0.0, dot(norm, v) - m_Bias) * ( 1.0/(1.0 + d) ) * m_Intensity;
}
vec2 reflection(in vec2 v1,in vec2 v2){
vec2 result= 2.0 * dot(v2, v1) * v2;
result=v1-result;
return result;
}
//const vec2 vec[4] = vec2[4](vec2(1.0,0.0), vec2(-1.0,0.0), vec2(0.0,1.0), vec2(0.0,-1.0));
void main(){
float result;
//vec2 vec[4] = { vec2(1.0, 0.0), vec2(-1.0, 0.0), vec2(0.0, 1.0), vec2(0.0, -1.0) };
vec3 position = getPosition(texCoord);
//optimization, do not calculate AO if depth is 1
if(depthv==1.0){
gl_FragColor=vec4(1.0);
return;
}
vec3 normal = getNormal(texCoord);
vec2 rand = getRandom(texCoord);
float ao = 0.0;
float rad =m_SampleRadius / position.z;
int iterations = 4;
for (int j = 0; j < iterations; ++j){
vec2 coord1 = reflection(vec2(m_Samples[j]), rand) * vec2(rad,rad);
vec2 coord2 = vec2(coord1.x* 0.707 - coord1.y* 0.707, coord1.x* 0.707 + coord1.y* 0.707) ;
ao += doAmbientOcclusion(texCoord + coord1.xy * 0.25, position, normal);
ao += doAmbientOcclusion(texCoord + coord2 * 0.50, position, normal);
ao += doAmbientOcclusion(texCoord + coord1.xy * 0.75, position, normal);
ao += doAmbientOcclusion(texCoord + coord2 * 1.00, position, normal);
}
ao /= float(iterations) * 4.0;
result = 1.0-ao;
gl_FragColor=vec4(result,result,result, 1.0);
//gl_FragColor=vec4(depthv,depthv,depthv, 1.0);
}
|
