| passName | The Shader Pass to use when executing ray tracing shaders. |
Selects which Shader Pass to use when executing ray/geometry intersection shaders.
This name is specified in the ShaderLab shaders used by Materials applied to Renderers used in ray tracing. If a shader doesn't have a Shader Pass with the specified name, then no ray/geometry intersection code is executed. This method must be called before calling RayTracingShader.DispatchRays.
The Shader Pass code can include optional closesthit or anyhit shaders.
For procedural ray-traced geometries, an intersection shader must be authored. The engine code will automatically enable a keywork named RAY_TRACING_PROCEDURAL_GEOMETRY if the geometry is proceduraly ray-traced.
The following example shader code returns the color red.
SubShader
{
Pass
{
// SetShaderPass must use this name in order to execute the ray tracing shaders from this Pass.
Name "Test"
// Add tags to identify the shaders to use for ray tracing.
Tags{ "LightMode" = "RayTracing" }
HLSLPROGRAM
#pragma multi_compile_local RAY_TRACING_PROCEDURAL_GEOMETRY
// Specify this shader is a raytracing shader.
#pragma raytracing test
struct AttributeData
{
float2 barycentrics;
};
struct RayPayload
{
float4 color;
};
#if RAY_TRACING_PROCEDURAL_GEOMETRY
[shader("intersection")]
void IntersectionMain()
{
AttributeData attr;
attr.barycentrics = float2(0, 0);
ReportHit(0, 0, attr);
}
#endif
[shader("closesthit")]
void ClosestHitMain(inout RayPayload payload : SV_RayPayload, AttributeData attribs : SV_IntersectionAttributes)
{
payload.color = float4(1, 0, 0, 1);
}
ENDHLSL
}
}