This is driving me mad, I'm converting a game I started in VB with Dx7 into a C++ project that uses Dx9. The whole thing is mainly number crunching to get things to render. The thing is the way the screen co-ordinates work has changed and I have tried to alter my code to adapt. The old axis went like a VB form (0,0 in the top left) and the maximum values were the same as the resolution. The new scale that Dx9 is using is 0,0 in the bottom left corner and the maximum values on both axis is 1.

I thought I'd managed ok but I came to transferring the scaling code over and it screwed up, I've spent most of the day tracing the numbers though the code and they appear to be the same (having to figure out the axis inversion in my head). I thinkthe rendering code is now the problem even though I thought I'd compensated for the changes properly there it appears I've made a mistake .

I can't be bothered to redo the code for the rendering tonight but I can only guess thats where the probem is .