Hi, I ported a project from 5.3 to 5.6 yesterday and overall everything is working great, it 100% looks smoother and I have more FPS than before. However… One of the 'effect’s we use is now ‘glitching’ it uses a RVT which controls a opacity map and I’m getting some odd results when it activates, after which it all runs fine.
I’m certain it’s to do with the RVT, if I change the Virtual texture content to exclude Alpha it visually looks fine minus the required alpha.
The best way to describe it is chunks are coming through and others are not before it’s fully loaded, Have RVT’s fundamentally changed now or do they use some sort of tiling? - The problem is we are not fully Unreal techs and although I’m gradually learning I’m not to the point I can debug this on my own.
Does any one have suggestions for how I can fix this please?
Ok So found the answer to my problem, I needed to tweak the number of tiles for the RVT texture, this was untouched from the 5.3 so what ever has happened from 5.3 to 6.3 means I had to modify it.
Ok I take that back, the above ‘fix’ works in Editor, soon as I package however it seems to revert back to previous artefacts - anyone have a clue as to why?
I’m fairly confident it’s to do with the Virtual texture pools, I’ve tried setting up some Fixed pools but when it comes to packaging up it still reverts to the issue.
Has anyone got any suggestions I could try? I even deleted out all the INI on a copy of the project ini;s encase somthing old was causing the issue, but I’m till getting the artefacts in packaged builds.
Bump - I’ve tried everything I can think of on this, it’s the one issue preventing me from going live with this version. All trials with 5.6 are great it’s soo much faster, smoother and better for pixelstreaming however, If I can’t resolve this issue it’s not going any where.
I can’t change the way this feature works, it has to use a Realtime virtual texture, but is there a way to stop it tiling / glitching?
So with a lot of back and forth with… ChatGPT ha! and some luck in the Epic docs the thing that solved it for me was “r.VT.MaxUploadsPerFrame” I played with different values, r.VT.MaxUploadsPerFrame 1 was the worst and r.VT.MaxUploadsPerFrame 128 was fine, so I played with the figure till everything was good without increasing it higher than I needed and settled on “r.VT.MaxUploadsPerFrame 128”.
I think VRT is one of thoes triangles of variables where if you play with one you need to adjust the other so I don’t think it’s a this setting will fix all your problems but if you need places to look you want to make sure you have your DefaultDeviceProfile.ini , ConsolVaribles.ini & Default Engine.ini all match up correctly. Half my issues was that what I was seeing in editor wasn’t what was happening when I packaged which added another level of complexity that was due to incorrect .ini’s. once I knew what ever I had inputted in the ini’s was controlling the package I started to play with figures.
adjusting the VRT in Realtime helped understand what affected what but wasn’t a proper reflection of what happened when packaged. Hope this helps someone as it was driving me mad for weeks / months.
my variables i used in the end which worked for me -
r.VT.Size=32768, r.VT.MaxUploadsPerFrame=128, r.VT.TileSize=1024, r.VT.TileBorderSize=8, r.VT.FeedbackBias=-2, single-channel pool 1536MB, fixed frame rate 30, AA=TSR.
