Hi! Hope somebody can help me figure this out.
I'm testing a new 6700XT card, and I noticed that on some games there is some kind of texture on transparent or translucent elements. I understand that sometimes the card can use dithering to solve complex situations with transparencies, but this looks more like a fixed pattern than dithering. So far I noticed it happening on Unity games, but I managed to grab this on Horizon Zero Dawn:
Note that there is no dithering gradient, but a fixed pattern (and looks like bump-mapped?) on the area the smoke is present.
I'm using Windows 10 and Adrenalin 22.11.1 Optional. The card is also working as PCIe 3, since I get problems on PCIe 4.
The effect rarely bothers me, but I want to be sure this is something related to the image processor and not a defect on the GPU.
Thanks in advance.
EDIT: forgot to mention, tested it with the old 22.5 drivers, also, doing a full reset on the Adrenalin options.
Ok, just to give some kind of closure to this.
The effect is indeed ordered dithering, and it is a technique in use for a long time in the industry on cases where you can't have a proper alpha channel.
Horizon Zero Dawn seems to be using this technique while rendering smoke and other fire effects. The dithering can even been seen on the volcano smoke on Forbidden West DLC:
But this not exactly what I see, and I think it is because I was using Fidelity FX, that was up-scaling the dithering, and applying some kind of sharpening to it, so it looks bigger and "embossed":
This is "ok", but I'm kind of wondering if the effect should be applied AFTER the up-scaling, based on this:
No sure if the dithering is considered "noise", probably not, but I would love to hear from someone that knows more about the technology. Also, I'm now kind of curious if newer versions of FSR changed or improved the way they handle dithering.
Some updates. Someone on the Steam forum with another 6700XT and 22.2.1 driver kindly provided me some similar screenshots of the game, and I can't see any pattern on the smoke (https://steamcommunity.com/app/1151640/discussions/0/3594464430433122356/). He/she recommended taking the picture using the photo mode feature, so I did, and I still can see the effect. Not sure if it is caused by the smoke or the heat distortion effect.
Looking at the GPU-Z information, seems that my vBIOS is up-to-date (113-EXT800254-L04). So, I'm going to experiment with the drivers, and if this is not resolved, I'm inclined to think something is wrong with this card.
Another person kindly provided a screenshot from the Linux version, and I can see the pattern on the fire. It is very faint, probably because of the resolution (I'm running the game in a 1680 monitor), but looks similar to what I have, so, might be dithering after all!
https://steamcommunity.com/sharedfiles/filedetails/?id=2892961192 (check the fire)
Another thing I noticed is that the FidelityFX engine increases the effect quite a lot. I was using the feature, so, that might also explain why I can see it more than I might usually do.
Ok, just to give some kind of closure to this.
The effect is indeed ordered dithering, and it is a technique in use for a long time in the industry on cases where you can't have a proper alpha channel.
Horizon Zero Dawn seems to be using this technique while rendering smoke and other fire effects. The dithering can even been seen on the volcano smoke on Forbidden West DLC:
But this not exactly what I see, and I think it is because I was using Fidelity FX, that was up-scaling the dithering, and applying some kind of sharpening to it, so it looks bigger and "embossed":
This is "ok", but I'm kind of wondering if the effect should be applied AFTER the up-scaling, based on this:
No sure if the dithering is considered "noise", probably not, but I would love to hear from someone that knows more about the technology. Also, I'm now kind of curious if newer versions of FSR changed or improved the way they handle dithering.
