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//TEST(compute):COMPARE_COMPUTE:-xslang -use-ir
//TEST_INPUT:Texture2D(size=4, content = one) : dxbinding(0),glbinding(0)
//TEST_INPUT: Sampler : dxbinding(0),glbinding(0,1,2,3,4,5,6)
//TEST_INPUT: ubuffer(data=[0 0 0 0], stride=4):dxbinding(0),glbinding(0),out
struct SurfacePosition
{
float3 position;
float3 normal;
float2 uv;
float3 color;
};
struct LightSample
{
float3 direction;
float3 intensity;
};
interface ILight
{
int getSampleCount(SurfacePosition pos);
LightSample getSample(SurfacePosition pos, int n, int i);
}
struct View
{
float3 cameraPos;
float3 cameraDir;
float2 viewportSize;
float4x4 viewTransform, projectionTransform, worldTransform,
viewProjTransform, invViewTransform, invWorldTransform;
SamplerState samplerState;
};
interface IBRDFEvaluator
{
associatedtype SurfaceProperty;
SurfaceProperty evalSurfaceProperty(SurfacePosition pos, View view);
float3 evalLighting(SurfaceProperty surf, LightSample lightSample);
float getOpacity();
}
interface IMaterial
{
associatedtype BRDFEvaluator : IBRDFEvaluator;
BRDFEvaluator evalPattern(View view, SurfacePosition surf);
}
struct DirectionalLight : ILight
{
float3 direction;
float3 intensity;
int getSampleCount(SurfacePosition pos)
{
return 1;
}
LightSample getSample(int n, int i)
{
LightSample ls;
ls.direction = direction;
ls.intensity = intensity;
return ls;
}
};
float3 EnvBRDFApprox( float3 SpecularColor, float Roughness, float NoV )
{
float4 c0 = float4(-1, -0.0275, -0.572, 0.022);
float4 c1 = float4(1, 0.0425, 1.04, -0.04);
float4 r = Roughness * c0 + c1;
float a004 = min( r.x * r.x, exp2( -9.28 * NoV ) ) * r.x + r.y;
float2 AB = float2( -1.04, 1.04 ) * a004 + r.zw;
AB.y *= min(50.0 * SpecularColor.g, 1.0);
return SpecularColor * AB.x + AB.y;
}
float PhongApprox(float Roughness, float RoL)
{
float a = Roughness * Roughness;
a = max(a, 0.008);
float a2 = a * a;
float rcp_a2 = 1.0/(a2);
float c = 0.72134752 * rcp_a2 + 0.39674113;
float p = rcp_a2 * exp2(c * RoL - c);
// Total 7 instr
return min(p, rcp_a2);
}
struct DisneyBRDFSurfaceProperty
{
float3 diffuseColor;
float3 fspecularColor;
float3 R;
};
struct DisneyBRDFEvaluator : IBRDFEvaluator
{
float3 baseColor;
float3 normal;
float3 emissive;
float roughness, metallic, specular, opacity;
typedef DisneyBRDFSurfaceProperty SurfaceProperty;
DisneyBRDFSurfaceProperty evalSurfaceProperty(SurfacePosition pos, View view)
{
DisneyBRDFSurfaceProperty rs;
float3 viewDir = normalize(pos.position - view.cameraPos);
rs.diffuseColor = baseColor * (1.0-metallic);
float dielectricSpecluar = 0.02 * specular;
float3 specularColor = float3(dielectricSpecluar - dielectricSpecluar * metallic)
+ baseColor * metallic;
float NoV = max(dot(normal, viewDir), 0.0);
rs.fspecularColor = EnvBRDFApprox(specularColor, roughness, NoV);
rs.R = reflect(-viewDir, normal);
return rs;
}
float3 evalLighting(DisneyBRDFSurfaceProperty surf, LightSample lightSample)
{
float RoL = max(0, dot(surf.R, lightSample.direction));
float dotNL = clamp(dot(normal, lightSample.direction), 0.01, 0.99);
float3 color = lightSample.intensity.xyz * dotNL *
(surf.diffuseColor + surf.fspecularColor * PhongApprox(roughness, RoL)) + emissive;
return color;
}
float getOpacity()
{
return opacity;
}
};
struct DisneyMaterial0 : IMaterial
{
typedef DisneyBRDFEvaluator BRDFEvaluator;
Texture2D diffuseMap;
DisneyBRDFEvaluator evalPattern(View view, SurfacePosition surf)
{
DisneyBRDFEvaluator rs;
rs.baseColor = diffuseMap.Sample(view.samplerState, surf.uv).xyz;
rs.normal = float3(0.0, 1.0, 0.0);
rs.emissive = float3(0.0);
rs.roughness = 1.0;
rs.metallic = 0.0;
rs.specular = 1.0;
rs.opacity = 0.5;
return rs;
}
};
__generic<TMaterial : IMaterial, TLight : ILight>
float4 computeShading(View view, SurfacePosition surfPos, TMaterial mat, TLight light)
{
TMaterial.BRDFEvaluator brdf = mat.evalPattern(view, surfPos);
int lightSampleCount = light.getSampleCount(surfPos);
float3 color = 0;
TMaterial.BRDFEvaluator.SurfaceProperty surfProp = brdf.evalSurfaceProperty(surfPos, view);
for (int i = 0; i < lightSampleCount; i++)
{
color += brdf.evalLighting(surfProp, light.getSample(surfPos, lightSampleCount, i));
}
return float4(color, brdf.getOpacity());
}
Texture2D diffuseMap;
SamplerState samplerState;
RWStructuredBuffer<float> outputBuffer;
[numthreads(1, 1, 1)]
void computeMain(uint3 dispatchThreadID : SV_DispatchThreadID)
{
View view;
view.cameraPos = 0.0;
view.cameraDir = float3(0.0, 0.0, -1.0);
view.viewportSize = float2(1920.0, 1080.0);
view.samplerState = samplerState;
DisneyMaterial0 material;
material.diffuseMap = diffuseMap;
DirectionalLight dirLight;
dirLight.direction = float3(0.0, 1.0, 0.0);
dirLight.intensity = float3(1.0, 1.0, 1.0);
SurfacePosition surfPos;
surfPos.position = float3(0.0, -10.0, -10.0);
surfPos.normal = float3(0.0, 1.0, 0.0);
surfPos.uv = float2(0.5, 0.5);
surfPos.color = 0.0;
float4 outVal = computeShading<DisneyMaterial0, DirectionalLight>(view, surfPos, material, dirLight);
outputBuffer[0] = outVal.x;
outputBuffer[1] = outVal.y;
outputBuffer[2] = outVal.z;
outputBuffer[3] = outVal.w;
}
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