about SphereMapping Texcoord

Original Post

Mar 19, 2009 at 1:04 AM

this is the calcuate sphere mapping uv code In Vertex Shader: the algorithm of calculate uv is from the DirectX SDK. float3x3 mat=ViewITXf; //ViewInverseTranspose matrix float3 n=mul(IN.Norma,mat); n=mul(n,float3(0.5,0.5,1.0))+float3(0.5,0.5,0); OUT.UV = n.xy; it seems there are something wrong from the result of FX Composer.

Jroggy

Mar 19, 2009 at 5:10 AM

I can't remember if FX Composer uses row major or column major matricies.. but try switching your matrix multiplications around, like so:

float3x3 mat=ViewITXf; //ViewInverseTranspose matrixfloat3 n=mul(mat,IN.Norma);n=mul(float3(0.5,0.5,1.0),n)+float3(0.5,0.5,0);OUT.UV = n.xy;

Namethatnobodyelsetook

118

Namethatnobodyelsetook

Mar 19, 2009 at 8:27 AM

I'm pretty sure you want the (world*view) inverse transpose, not just view.

Topic Locked