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KhronosGroup / glTF-Sample-Assets

To store all models and other assets related to glTF
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NormalTangentMirrorTest has (compression?) artifacts in normal map #58

Closed Raveler closed 7 months ago

Raveler commented 6 years ago

If you take a look at the NormalTangentTest_Normal.png file in the NormalTangentMirrorTest example, you'll notice some visible artifacts (gradients, color diffs) around the globes.

This causes visible artifacts when rendering the model, and I believe these are unintentional. Here's two screenshots of the same artifact, one with my own engine and one with babylonjs:

image

image

cx20 commented 6 years ago

I tried posterization of NormalTangentTest_Normal.png at paint.net. It seems that artifacts certainly exist. before: image after: image

emackey commented 6 years ago

My current theory is that I should have triangulated the quads before baking these normals. Substance Painter (or the intermediate export format that got the mesh over to SP) may have triangulated them differently from the final glTF. Will have to re-do this bake at some point.

emackey commented 6 years ago

But it's safe to ignore the artifacts. The model is about testing whether the reflections are at all rightside-up, or if the normal vector math is completely broken. The minor artifacts don't detract from the ability to see if the math is right, because when it's wrong it's completely sideways.

Raveler commented 6 years ago

Sure, but I would at least mention it in the description. I spent a couple of hours looking for errors in my rendering until I figured out it was the normal map.

DRx3D commented 11 months ago

@emackey : Has this issue been resolved? If not, is it possible to do an update to the README for this model in glTF-Sample-Assets repo? Default is to close by 27 Nov.

lexaknyazev commented 10 months ago

We should fix those artifacts. Please transfer.