I''m trying to write a sample program that use vertex shader and immediate mode ( i means the input vertices are already in screen position). For example: vertices = 0,0 0,480 640, 480 640, 0 and my vertex shader is something like this v.1.1 mov oPos, v0 mov oD0, c0 This seems not to work. looks like D3D is doing the projection, thing I don''t want, and then draw nothing is it possible ? in fact this is to set a primitive covering the whole screen (in 640x480 and i want to use a vertex shader for doing some UV coordinates modifications Is someone already tried to do that ? you can download the sample code i''ve trying to make it works http://www.realtech.scene.org/download/vs8-im.zip