Well. My question is very simple : I would like to do " arithmetics " operations between 2 images, of any size, with DirectX (DDraw or D3D) The operator multiplication can to be an other operation, for instance add/soustract/divide … So, how to do this by using DirectX, in order to use the hardware acceleration (HAL) ? ! (here, time is critical). There''s a solution with textures, but the problem is the SIZE : it must to be a multiple of two, not any size. And there''re many others problems (surface->texture take lots of time…). Anybody has got an idea ? ! Thanks. .JuJ. (french) Mail-me at : juj1@caramail.com