Ok, here''s some code. It''s a few years old so I would probably not do it like this today but it worked then, and it should work for you too.
void CFlatSurface::SetTextureData(CTextureContainer *pTexture, float fWidth, float fHeight, float fU, float fV, float fRotate, float fSkew){ D3DMATRIX dmtxRotate; D3DVECTOR dvecUPrim, dvecVPrim; D3DVECTOR *pdvecVertex; if( m_pTextureContainer ) m_pTextureContainer->Release(); m_pTextureContainer = pTexture; if( m_pTextureContainer ) { m_pTextureContainer->Acquire(); m_bTextureApplied = TRUE; } else { m_bTextureApplied = FALSE; return; } m_fTextureWidth = fWidth; m_fTextureHeight = fHeight; // Get the coordinate axises of the plane if( fabs(m_dvecNormal.dvY) < (float)sqrt(0.5) ) { // A vertical plane (almost) m_dvecTextureUAxis = Normalize(CrossProduct(m_dvecNormal,Vector(0,1,0))); m_dvecTextureVAxis = Normalize(CrossProduct(m_dvecNormal,m_dvecTextureUAxis)); } else { // A horizontal plane m_dvecTextureUAxis = Normalize(CrossProduct(m_dvecNormal,Vector(0,0,1))); m_dvecTextureVAxis = Normalize(CrossProduct(m_dvecNormal,m_dvecTextureUAxis)); } // Rotate the axises dmtxRotate = RotationMatrix(m_dvecNormal, fRotate); VectorMatrixMultiply(m_dvecTextureUAxis, m_dvecTextureUAxis, dmtxRotate); VectorMatrixMultiply(m_dvecTextureVAxis, m_dvecTextureVAxis, dmtxRotate); // Skew them dmtxRotate = RotationMatrix(m_dvecNormal, fSkew); VectorMatrixMultiply(m_dvecTextureUAxis, m_dvecTextureUAxis, dmtxRotate); m_dvecTextureOrigo = Vector(0,0,0); m_dvecTextureOrigo = m_dvecTextureOrigo - fU * (m_fTextureWidth*m_pTextureContainer->GetWidth()/g_wTextureSize) * m_dvecTextureUAxis; m_dvecTextureOrigo = m_dvecTextureOrigo - fV * (m_fTextureHeight*m_pTextureContainer->GetHeight()/g_wTextureSize) * m_dvecTextureVAxis; dvecUPrim = m_dvecTextureUAxis - DotProduct(m_dvecTextureUAxis, m_dvecTextureVAxis) * m_dvecTextureVAxis; dvecVPrim = m_dvecTextureVAxis - DotProduct(m_dvecTextureVAxis, m_dvecTextureUAxis) * m_dvecTextureUAxis; // Compute the texturecoordinates pdvecVertex = m_pShell->GetVertexList(); for( int n = 0; n < m_iIndexCount; n++ ) { m_pvtxIndex[n].fTU = DotProduct(pdvecVertex[m_pvtxIndex[n].wIndex]-m_dvecTextureOrigo,dvecUPrim)/ (dvecUPrim.dvX*dvecUPrim.dvX+dvecUPrim.dvY*dvecUPrim.dvY+dvecUPrim.dvZ*dvecUPrim.dvZ)/ (m_fTextureWidth*m_pTextureContainer->GetWidth()/g_wTextureSize); m_pvtxIndex[n].fTV = DotProduct(pdvecVertex[m_pvtxIndex[n].wIndex]-m_dvecTextureOrigo,dvecVPrim)/ (dvecVPrim.dvX*dvecVPrim.dvX+dvecVPrim.dvY*dvecVPrim.dvY+dvecVPrim.dvZ*dvecVPrim.dvZ)/ (m_fTextureHeight*m_pTextureContainer->GetHeight()/g_wTextureSize); }}
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WitchLord
You know how when you are trying to fix a problem for days, and you end up repeating things you''ve already tried ? Well i''m on the 6th time round them all i think 
If you could find it in your heart to provide a bit of source which I can disect and implement, i don''t want to completely rip it off, just to understand how it works for future use.
