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shaderhlsl

HLSL getting world position of PIXEL

what I'm searching for is a simple way to get the world space coordinates for each pixel running throu the pixel shader.

I've found this topic: Pixel World Position

and it seems to work, but I'm yet not that used to shader language that I completly understand it.

Isn't there an easy way to solve this?

Kind regards, Marius

Solution

  • Easiest way is to pass it from the vertex shader as texture coordinate, like this (dx9 sample easy to convert to 10 if you use it):

    cbuffer cbmat : register( b0 )
{
    float4x4 tW; //World transform
    float4x4 tWVP: //World * View * Projection
};



struct vs2ps
{
    float4 Pos : POSITION;
    float4 TexCd : TEXCOORD0;
    float3 PosW : TEXCOORD1;
};

vs2ps VS(float4 Pos : POSITION,float4 TexCd : TEXCOORD0)
{
    vs2ps Out;
    Out.Pos = mul(Pos, tWVP);
    Out.TexCd = TexCd;
    Out.PosW = mul(Pos, tW);
    return Out;
}

float4 PS(vs2ps In): COLOR
{
    return float4(In.PosW,1.0f);
}