D3DTOP_ADD and Nvidia cards

That last one looks more like you have Z-Write/Z-Test and a render order issue.
Although I would think you would either get green or red depending on the render order…
I've never seen a problem with the additive blend.

Quote:

Original post by Scythen That last one looks more like you have Z-Write/Z-Test and a render order issue. Although I would think you would either get green or red depending on the render order… I've never seen a problem with the additive blend.

In this case, I don't think it is a render order issue. The Green line appears behind the red circle, and is rendered first. Also, if it were a render order issue, I think the problem would also exist on my ATI card.

Any thoughts?

A couple of things to try:

1. Run your application under the REFRAST - depending on what result you get it should indicate whether the NV or ATI hardware is correct. It's likely to just prove the NV card is wrong, but it can't hurt to be sure [wink]

2. Try some different driver combinations if possible. See if it's something that has been fixed/introduced via the software rather than the hardware.

I suppose neither of those present a solution, but it might allow you to write in an NV-specific path. You could also try bugging Nvidia developer relations.

I checked the DX caps database, and every piece of hardware seems to support the additive operation, but I'd make sure that you're not using any other blending modes that might not be supported by the NV hardware.

hth
Jack

Ahh... the old REFRAST. Good call. I've had problems getting that to work on my ATI cards, and it is impossibly slow, but that's not a bad place to start.

Thanks for the advice