Shader stages

The function for each stage has a predefined name, so we recommend you don't change it.

HSMain for hull shader
HSConstantMain for patch constant function
DSMain for domain shader
VSMain for vertex shader (takes no arguments)
GSMain for geometry shader
PSMain for pixel shader (takes no arguments)
CSMain for compute shader (takes no arguments)

These are all void methods.

The geometry and tessellation shaders need some kind of predefined structure as input and output. However, since Stride shaders are generic, it's impossible to know beforehand what the structure will be. As a result, these shaders use Input and Output structures that are automatically generated to fit the final shader.

Vertex shader

A vertex shader has to set the variable with the semantic SV_Position. In ShaderBase, it's ShadingPosition.

For example:

override stage void VSMain()
{
    ...
    streams.ShadingPosition = ...;
    ...
}

Pixel shader

A pixel shader has to set the variable with the semantic SV_Target. In ShaderBase, it is ColorTarget.

For example:

override stage void PSMain()
{
    ...
    streams.ColorTarget = ...;
    ...
}

Geometry shader

An example of geometry shader:

[maxvertexcount(1)]
void GSMain(triangle Input input[3], inout PointStream<Output> pointStream)
{
    ...
    // fill the streams object
    streams = input[0];
    ...

    // always append streams
    pointStream.Append(streams);
    ...
}

Input can be used in the method body. It behaves like the streams object and contains the same members.

Output is only used in the declaration of the method. You should append the streams object to your geometry shader output stream.

Tessellation shader

An example of a tessellation shader:

[domain("tri")]
[partitioning("fractional_odd")]
[outputtopology("triangle_cw")]
[outputcontrolpoints(3)]
[patchconstantfunc("HSConstantMain")]
[maxtessfactor(48.0)]
void HSMain(InputPatch<Input, 3> input, out Output output, uint uCPID : SV_OutputControlPointID)
{
    ...
    output = streams;
}

void HSConstantMain(InputPatch<Input, 3> input, const OutputPatch<Input2, 3> output, out Constants constants)
{
    ...
    output = streams;
    ...
}

[domain("tri")]
void DSMain(const OutputPatch<Input, 3> input, out Output output, in Constants constants, float3 f3BarycentricCoords : SV_DomainLocation)
{
    ...
    output = streams;
    ...
}

Input and Input2 both behave like streams.

Note

Don't forget to assign output to streams at the end of your stage.

Compute shader

An example of a compute shader:

[numthreads(2, 3, 5)]
void CSMain()
{
    ...
}

You can inherit from ComputeShaderBase and override the Compute method.