   Problem with ATI drivers - polygon edges
  I recently got a new ATI video card for a new game I'm working on. It's working great, but there's one issue that I've been having that I'm not sure how to fix under DirectX. It seems that if I render two polygons with touching edges, sometimes a small gap appears between them. This does not happen on my old nVidia card. Here's a screenshot demonstrating what's going on:You can see some bright dots in middle of the screenshot, which is the skybox bleeding through.Any idea how to fix this?   
  Are you using indexed vertices, or are you just duplicating the vertices? Are you absolutely sure that the vertex positions are exactly the same? Remember that floating point rounding could cause the numbers to be off unless you directly copy one value to another.   ;  Have you tried using the REF rasterizer?   ;  Well, each face has its own unique set of vertices that are indexed. I've done some more testing, and the problem doesn't happen along a boundary of two faces sharing two vertices in the same position; instead, it only happens in a situation like this: ________________| || || ||________________|    |    |    |    |    |    |    |____|Whereas something like this: ________|   ||   ||   ||________||   ||   ||   ||________|... produces no problems.Also, I've tried the REF rasterizer, but I just get a black screen.   ;  Strange. Ref rasterizer should show you same scene (even if it will need a lot of time to render it).   ;  Well, I've got a lot of stuff going on: shading, rendering to a texture, multisampling, an alternate depth-stencil surface, etc. I would think any of those things could be screwing with it.   ;  If the reference rasterizer doesn't render anything, it's likely that you're doing something that is relying on undefined behaviour. Do the Debug Runtimes say anything?   ;  Yeah, I was using D3DTEXF_LINEAR with StretchRect(), which the reference rasterizer didn't like. Oops!Anyway, now that I have that working, the bright dots do NOT appear with the reference rasterizer - they only appear when using hardware. So, does this mean that it's an ATI driver issue?   ;Quote:Original post by Carnevil_Yeah, I was using D3DTEXF_LINEAR with StretchRect(), which the reference rasterizer didn't like. Oops!Anyway, now that I have that working, the bright dots do NOT appear with the reference rasterizer - they only appear when using hardware. So, does this mean that it's an ATI driver issue?Almost definitely. Do you have the latest drivers for your card? And what card do you have?   ;  Wow, ATI has buggy drivers? There's a shocker! I'm using Catalyst v9.5, which is the latest version to my knowledge.EDIT: Just upgraded to 9.6, and it doesn't help.[Edited by - Carnevil_ on June 25, 2009 9:46:22 AM]