Direct3D rendering 2D images with “multiply” blending mode and alpha

Question

I\'m trying to replicate the Photoshop filter multiply with Direct3D. I\'ve been reading and googling about the different render states and I\'ve got the effect almost worki

Answer 1

dev->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_DESTCOLOR);
dev->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);

Will do the trick. You cannot use the 'alpha' from the diffuse vertex color anymore though. Setting a low alpha on the vertex colors will actually brighten your overlaying pixels.