Vertex Buffer 2GB size limit?

Development Rendering
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1

There appears to be a 2GB limit per Vertex Buffer object, and as soon as it’s reached no primitives belonging to this VB are being rendered. Running stat rhi still shows correct number of primitives drawn, draw calls, VRAM usage of VB and IB, etc. but nothing is actually visible.

This is reproducible even if the VB is not fully populated with the usable data. If you, for example, allocate 100MB to the VB, then populate the whole 100MB of it with data, it renders just fine. But if you then change the allocation size to above 2GB, leaving everything else intact, you get nothing rendered.

Am I missing something?

EDIT:
Correction: they all render without material (pure black), cramped on top of each other at [0,0,0], even tho, stat rhi doesn’t report them as such, judging by the numbers it shows.

248590-vb2gb.jpg
248590-vb2gb.jpg2652×1059 217 KB

The plane at the bottom is just few polys, used purely as orientation reference

2

Try running with -d3ddebug. I suspect you’re just hitting the limits of what d3d11 allows for buffer sizes.
-d3ddebug should dump to the log when you’re attached with visual studio and let you know if something is wrong there.

3

Thanks for that, will check when I get to the machine. But consulting the link it does indeed look like there’s a hard cap of 2048 MB (or 25% of ded VRAM) hard limit per resource. This is going to seriously mess up my plans. Also, I thought it was d3d12, good to know.