My example work on AMD but not on NVIDIA

Yeah, I was kinda surprised that a zero instanceCount wasn’t listed under Valid Usage as being invalid.

It actually seems to be valid and there may be use cases for an instanceCount of zero (having shaders write to an indirect buffer e.g.). For details see this issue for the Vulkan docs.

But from my understanding passing zero should never draw anything, which is what the AMD driver does, while NVIDIA does handle this correct. There is already an issue to add a test to the Vulkan CTS for that.

I accept that it’s reasonable for the indirect rendering case for it to be zero. But if you’re drawing from the API, there’s really no need.

Then again, I suppose if the hardware can handle an indirect zero, then it would be consistent to do it from the CPU side too. After all, Vulkan’s all about getting out of the user’s way.

AMD best of the best :slight_smile:
NVIDIA weaklings. Can`t rendering when Instance count = 0

I noticed that Nvidia’s more whimsical to write Vulkan code. And more crushed.

But examples from NVIDIA site not run on Radeons Video Cards.
I mean demo fishes.
NVIDIA uses its expansion.

AMD best of the best
NVIDIA weaklings. Can`t rendering when Instance count = 0

… what?

You said to render zero instances of the vertex data. If it renders even a single instance, then it’s not doing what you told it to.

0 is a valid instance count, and the clear, well-defined, well-specified behavior for it is to render nothing. The Vulkan specification makes this abundantly clear.

AMD is not “best of the best”; they’re broken! It’d be no different from you telling it to render 0 vertices, but the driver arbitrarily decides that you really meant 20 vertices.

Now my example run on NVIDIA but on first frame 3d model and get Device_lost ! NVIDIA weaklings :slight_smile:
On AMD work fine !

http://s000.tinyupload.com/index.php?file_id=34973651486798537235

[QUOTE=Ronniko;40595]Now my example run on NVIDIA but on first frame 3d model and get Device_lost ! NVIDIA weaklings :slight_smile:
On AMD work fine !

http://s000.tinyupload.com/index.php?file_id=34973651486798537235[/QUOTE]

Device Lost is probably a fault on your side. I’m developing my examples on multiple vendors (NVIDIA, AMD, etc.) and if you stick to the specs (and keep validation clean) examples should work fine across them. If you’re sure that you hit a driver problem, do a repo case and inform the driver guys from the IHV it’s happening.

If you want to get real help, please post your code somewhere or upload a RenderDoc trace so we can at least check the API calls made.

[QUOTE=Ronniko;40595]Now my example run on NVIDIA but on first frame 3d model and get Device_lost ! NVIDIA weaklings :slight_smile:
On AMD work fine ![/quote]

It is a poor carpenter who blames his tools…

For this reason NVIDIA set in fishes demo expansion only for NVIDIA videocards ? :slight_smile:
Poor NVIDIA :frowning:

Ha-Ha !!!
Work on Win XP on NVIDIA 720
Simple triangle on FASM !
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