Hello, I'm new to this forum, so I apologize for starting out by asking for help.

I'm having a problem trying to get my custom vertex shader in DirectX 8 to recognize that I'm trying to send it transformed vertices for the screen sized quad I'm trying to render. Instead, the quad appears to be picking up the world/view transformation from the last object I rendered in my scene.

Here's a screen shot:
http://www.epochstar.com/VS1.jpg

Notice my quad is being rendered in the upper left corner of the screen. I'm trying to get it to take up the entire screen. Is there something I can do in my vertex shader to make it recognize I'm dealing with pre-transformed vertices? Is there anything else I can do to get my quad to render full screen?

Thanks

While the screenshot helps illustrate the problem, without some relevant code posted things become a guessing game. So here's my first guess ;)

In your FVF declaration are you using D3DFVF_XYZ instead of D3DFVF_XYZRHW?

If you are using a vertex shader, then you have to map screen coordinates to the viewport clipping volume inside the shader. From DxDocs, "Microsoft Direct3D assumes that the viewport clipping volume ranges from -1.0 to 1.0 in X, and from 1.0 to -1.0 in Y."

I've run across and solved this problem numerous times. Post more specifics and we'll help you out further if you need it.

Remember that you must set the matrices before (for shader) the object and need to also recalculate them again (if there is some chances been made).