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Artifacts in translucent mode

Hi to all. I am having some troubles with a skirt I have in my scene when I am changing its material to translucent mode, some artifacts are then appearing. I have checked the mesh, the normals, and the material values, and I am not able to fix this. Can anyone give me a solution in order to solve this? is my first project in Unreal. Thank you!

Try enabling “Two-Sided” in the material properties, and enable it in the mesh.

This is a translucency sorting issue, how you go about fixing it depends on what you’re trying to accomplish. In general the best approach is to either used masked instead of translucency, or break off the translucent parts of the mesh into their own material, then use opaque on everything else.

I already tried this, does not solve it

I already have tried masked and all other options and does not fix it. About your other proposal, it is already like that, the translucent part has its own ID and even I paint in black those parts it keeps appearing with the artifacts

Try it again and post the result

in mixed there are no artifacts, but the transparency is not smooth anymore

Your options aren’t good.

  1. Do something else. Redesign your skirt. This is your best option.
  2. You can use a masked material by piping the translucency mask into a DitherTemporalAA node in order to smooth out the transition but it comes with its own downsides, namely that it only has a few steps of translucency and if you use temporal AA then it will smear during any motion.
  3. Render the material to custom depth and depth test the pixels to determine the sort order. This will most likely not work in your case because you lose all translucent overlap so I would expect that you would get artifacts anywhere that you have overlapping translucent surfaces that are not at 0 or 1 opacity. But if you’re desperate I suppose you could try it.
  4. Come up with some other even more elaborate way to render the material.

You’re trying to do something that can’t really be done easily. As I said before, your original artifact is caused by translucency sorting. The engine needs to know which surfaces are in front of other surfaces, I believe it usually does this by using the object position, so breaking your surfaces up into multiple objects will usually help manage the issue. But that is not a practical option in the case of a sheer translucent skirt.