Hello, I’m trying to use path tracer but when I turn it on, some of my megascan assets are rendering black. The weird thing is, I have many copies of the same asset all over my map, but only some are affected, it seems to be random…
PT
Lumen
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I am having the very same issue… Have you found a solution to this by any chance, @YosiSK ?
I had a very similar issue, but with Megascans assemblies. It turned out that, for some reason, they had a negative scale transformation applied to some of the instanced meshes, causing mirroring. To explain, if you apply a negative scale to an actor (e.g., using -1 on the X-axis), it mirrors along that axis. This mirroring can result in inverted normals when using path tracing, at least within the Assemblies. Unfortunately, the Assemblies seemed to ‘forget’ about this operation; in fact, from the transformation tab, the scale still showed as 1,1,1. In my case, it was on the X-axis, so I solved it by manually setting the X transformation back to 1 (typing 1 again) and removing the 180-degree rotation on the X-axis (in my case).
follow this steps:
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open your assembly
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find which meshes is being rendered black (Isolate it by hiding them one by one.
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once you found it, go to the details panel, instances tab. You should probably have a rotation somewhere of almost 180°, probably this is it. In my case it was the X axis.
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type 1 on the corresponding scale axis, and put back to 0 the rotation otherwise the meshes will be upside down.
Thank you I will try looking into it. BTW I recently tried using PT again and strange thing is that using MRQ and Path-traced render the black objects disappeared, they only appear in 3D view.
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Ok update on the situation, I’ve just found out that the reason it renders ok is because I use command r.RayTracing.Nanite.Mode 1 that is used for rendering Nanite geometry when using ray tracing.
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thanks a lot ,it wokr!!!
Although this method is effective, I have a problem. When I use path tracing to render the “Electric Dreams Env” scene, I find that some assets of the level instance blueprint appear black. Even if I turn off the nanite of the static model, it still cannot be solved. When I render the static model in the scene alone, it will not turn black. So I think this problem is partly related to the level instance blueprint. I encountered the same problem when testing the assets of “Uscans Workshop 01” before.
虽然这个方法有效，但我有一点太理解，当我路径路径追踪渲染Electric Dreams Env 的场景时，发现有部分关卡实例蓝图的资产会出现黑色，就算我关闭了静态模型的nanite，还是无法解决，而单独将静态模型放到场景里渲染，不会变成黑色，所以我觉得这个问题，有部分原因是跟关卡实例蓝图有关。之前测试Uscans Workshop 01 的资产也遇到同样的问题。
