When rendering a SurfaceAppearance consisting of Transparency, a Color Map with alpha, and a Normal Map, at a certain range black artifacts appear in the shader.
I was not able to see these on mobile, but it happens consistently on PC on a wide range of normal maps.
The really strange part is that it only appears for a small band of distance.
It is not there between 0 and 200 studs away
It appears when an object is between 200 and 205 studs away
It is not there when an object is 206+ studs away
Extra details:
Happens in both Future and Shadowmap
Happens regardless of the shadow settings (cast shadows, global shadows, time of day)
Note: I thought it might of been the sparkly normals on the edge of the balls, but it wasn’t that - I tested those normals and they render correctly.
Speculation: I think mipmap generation for normals is failing and making degenerate/length=0 normals when it’s a mix of transparent and not transparent pixels, as all of these artifacts appear where the alpha changes from 0 to 1
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I had same issue. I partially solved it, by recoloring transparent pixels. But still bad result. Hope this bug will be fixed.
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Just want to point out that there are some black pixels on your normal maps along the shapes’ edges, mostly on the top right which is where the issue occurs, in the dark blue the contrast is fairly low so the effect may not be as pronounced, which is also where the effect doesn’t seem to appear as much. Have you tested this with those buffed away? Roblox does have trouble with alpha boundaries and these could be getting blown up into the problem you’re seeing, but I’m also not sure if this would be a bug if it’s just black present on the normal; I don’t think anything handles any amount of black on a normal map gracefully.
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It still happens with that cleaned up.
Those normals are valid, with a Z still pointing out of the map
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I can take a look at the issue. Could you send a .rbxl file of the experience in the video you linked? I am having trouble recreating this bug for some reason using the files sent as colormap and normal map.
Just out of curiosity also, I was wondering how developers have been measuring studs in the studio app. I can’t recall if there are straightforward tools for doing this.
I just eyeballed it . Those numbers I originally posted were just made up for reference - approximately about what it looked like.
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Quite literally using a part and dragging it out like a measuring tape!
A lot of devs also like the default floor-texture which is 1-stud increments
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Hello, sorry to be a pest but any updates? 
Hey there MrChickenRocket! I believe I merged a fix to this issue. I believe it will be rolled out to the next Studio release.
It will have a small section in the patch notes mentioning surface appearances in the release it comes out on.
The issue involved pixels with surface normals with a blue value of 128 not being handled correctly at that distance.
Thanks for submitting this bug report! Please let me know if the fix was what you expected, and I hope you keep submitting bug reports in the future.
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Fantastic news, that’s what I thought might of been going on. Phew! Thankyou!
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