Grounded Pilot

Hi, I have been developing a VB6 DX8 3D engine for some time and I have a terrain made from one continoues triangle strip which winds back and forth.

Now when i recently tried to run this engine on a IBM T41 laptop, the terrain didn't appear. Debugging the code on the laptop itself shows all kinds of corruption, once the triangle strip reverses direction everything gets either corrupted or not drawn (depends on total number of primitives drawn)

Any reason why one graphics card cannot cope and another can? Surely even if the vertices and incorrectly programmed, the triangle strip should always be drawn.

STufaro

The T41 may not have DirectX 8 compatible hardware (though it's modern enough that it should...)

AdrianDeAngelis

I found for myself that when I made the switch from an older videocard to a new one that certain rendering options (eg colourkeying etc...) were not supported the same as on the old card. Running those caused all primitives and blits afterwards to be totally messed up so it might be something else that you are doing, not the triangle strips.

Try rendering without any textures using just a null texture... If you get correct geometry then consider a texture memory/rendering incompatability... first one I can think of is trying to render from a non-square texture.

Grounded Pilot

It all works now, it was caused by a long winding trianglestrip which winds back and forth for the terrain. I don't know why it didn't work but all I did was to render the terrain a many individual trianglestrips and all works again on different PCs/graphics cards.

STufaro

Ah, yes, the importance of the Caps - the amount of primitives to draw in a single call is limited by the hardware.