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

It sounds like you want:

dst.rgb = (src.a * src.rgb) * ((1 - src.a) * dst.rgb)

You would use D3DRS_BLENDOP to do that, but unfortunately there isn't a D3DBLENDOP_MULTIPLY. I don't think this operation is possible without a fragment shader.