D2D_PS_ENTRY function

Article
03/22/2021

A macro that defines a pixel shader entry point with the given function name.

Syntax

void WINAPI D2D_PS_ENTRY(
  in string Entryname
);

Parameters

Entryname [in]: The pixel shader entry point name.

Return value

This function does not return a value.

Remarks

Use this macro instead of specifying the entry point s input signature in the normal manner: all parameters are implicit and added by Direct2D during compilation depending on the compilation target type (full shader or export function).

#define D2D_INPUT_COUNT 1 
#define D2D_INPUT0_SIMPLE 
#include  d2d1effectauthor.hlsli  

D2D_PS_ENTRY(LinkingCompatiblePixelShader) 
{ 
    float4 input = D2DGetInput(0);  

    input.rgb *= input.a; 

    return input; 
}

In this short example note that no function parameters are declared, that the number of inputs and type of each input is declared before the entry function, the input is retrieved by calling D2DGetInput, and that preprocessor directives must be defined before the helper file is included.

A linking-compatible shader must provide both a regular single-pass pixel shader and an export shader function. The D2D_PS_ENTRY macro allows each of these to be generated from the same code, when used in conjunction with the shader compilation script.

When compiling a full shader, the macros are expanded into the following code, which has a D2D Effects-compatible input signature.

Texture2D<float4> InputTexture0; 
SamplerState InputSampler0; 

float4 LinkingCompatiblePixelShader(
    float4 pos   : SV_POSITION,   
    float4 posScene : SCENE_POSITION,    
    float4 uv0  : TEXCOORD0 
    ) : SV_Target 
{ 
    float4 input = InputTexture0.Sample(InputSampler0, uv0.xy);  

    input.rgb *= input.a; 

    return input; 
}

When compiling an export function version of the same code, the following code is generated:

// Shader function version 
export float4 LinkingCompatiblePixelShader_Function( 
    float4 input0 : INPUT0 
    ) 
{ 
    input.rgb *= input.a; 

    return input; 
}

Note that the texture input, normally retrieved by sampling a Texture2D, has been replaced with a function input input0.

Requirements

Requirement	Value
Header	D2d1effecthelpers.hlsli
DLL	D2d1.dll