I'm drawing polygons in an orthogonal projection, but I'm experiencing some texture distortion when I try to draw a quadrilateral that isn't a parallelogram. For example: here's my test texture: Now here's what happens when I try to draw this texture as a trapezoid, using two triangles: I can see what's happening. When the first primitive is drawn, it doesn't know about the other one; so it just assumes that it's part of a parallelogram, and stretches the texture accordingly. I'm drawing the quad as a triangle strip, but it still distorts. My vector format is D3DFVF_XYZ | D3DFVF_TEX1. There must be some way of making the texture stretch according to each vertex of the quad. Do I need to add anything to my vertex format? Or is there some other special way of rendering the quad? Thanks!

OpenGL solution. Direct3D solution follows similarly.