123a192963
SSAO is a medium frequency effect, using half res fbo is fine and improve performance and look by doing an additionnal bilinear filtering. Also tune up some values.
69 lines
2.1 KiB
GLSL
69 lines
2.1 KiB
GLSL
uniform sampler2D ntex;
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uniform sampler2D dtex;
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uniform sampler2D noise_texture;
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uniform mat4 invprojm;
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uniform mat4 projm;
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uniform vec4 samplePoints[16];
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#if __VERSION__ >= 130
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in vec2 uv;
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out float AO;
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#else
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varying vec2 uv;
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#define AO gl_FragColor.x
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#endif
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const float strengh = 3.;
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const float radius = 1.f;
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#define SAMPLES 16
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const float invSamples = strengh / SAMPLES;
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vec3 rand(vec2 co)
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{
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return texture(noise_texture, co * pow(3.14159265359, 2.)).xyz;
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}
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vec3 DecodeNormal(vec2 n);
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void main(void)
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{
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vec4 cur = texture(ntex, uv);
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float curdepth = texture(dtex, uv).x;
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vec4 FragPos = invprojm * (2.0f * vec4(uv, curdepth, 1.0f) - 1.0f);
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FragPos /= FragPos.w;
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// get the normal of current fragment
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vec3 norm = normalize(DecodeNormal(2. * texture(ntex, uv).xy - 1.));
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// Workaround for nvidia and skyboxes
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float len = dot(vec3(1.0), abs(cur.xyz));
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if (len < 0.2 || curdepth > 0.9955) discard;
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// Make a tangent as random as possible
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vec3 randvect = rand(uv);
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vec3 tangent = normalize(cross(norm, randvect));
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vec3 bitangent = cross(norm, tangent);
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float bl = 0.0;
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for(int i = 0; i < SAMPLES; ++i) {
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vec3 sampleDir = samplePoints[i].x * tangent + samplePoints[i].y * bitangent + samplePoints[i].z * norm;
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sampleDir *= samplePoints[i].w;
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vec4 samplePos = FragPos + radius * vec4(sampleDir, 0.0);
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vec4 sampleProj = projm * samplePos;
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sampleProj /= sampleProj.w;
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bool isInsideTexture = (sampleProj.x > -1.) && (sampleProj.x < 1.) && (sampleProj.y > -1.) && (sampleProj.y < 1.);
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// get the depth of the occluder fragment
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float occluderFragmentDepth = texture(dtex, (sampleProj.xy * 0.5) + 0.5).x;
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// Position of the occluder fragment in worldSpace
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vec4 occluderPos = invprojm * vec4(sampleProj.xy, 2.0 * occluderFragmentDepth - 1.0, 1.0f);
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occluderPos /= occluderPos.w;
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bool isOccluded = isInsideTexture && (sampleProj.z > (2. * occluderFragmentDepth - 1.0)) && (distance(FragPos, occluderPos) < radius);
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bl += isOccluded ? samplePoints[i].z * smoothstep(5 * radius, 0, distance(samplePos, FragPos)) : 0.;
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}
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AO = 1.0 - bl * invSamples;
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}
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