Backface Culling On Meshes With Only One Side

I have some meshes of foliage (such as leaves), which are made up of a single mesh plane with no thickness. The problem is that Roblox has backface culling, which means that only the front side of that mesh is visible, and the backside is hidden.

Is there any workaround for this?

  • I know that I can add thickness to the mesh in Blender, but that is not ideal since it adds to the polygon count, and I have too many meshes to convert.

  • The only other thing I can think of trying is to use two versions of the same mesh, one with regular normals, and one with flipped normals, and then overlap the two meshes.

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Could it be a UV mapping issue? It’s worked for me and many others.

Try duplicating the faces and flip them in Blender. That way the plane will be visible from both sides, without needing two separate meshes.

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It is unfortuantely not possible to make a face visible on both sides. As Coeptus mentioned, your only option is to duplicate the faces and flip the normals.

This is pretty easy to do in Blender. Select the faces you want inverted, press Shift + D to duplicate them, then press W and select “Flip Normals”

I highly recommend not to use this method if you plan on using a lot of trees in your game.

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No, if you have a mesh that is just a plane with no thickness, then only the front side will show in Roblox.

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May be a tad old. but this has helped me out! Pretty annoying Robox don’t allow backface culling on a plane, would be great to make it double sided.

I have a question, Instead of doing this in blender, is there any possible way that, if I was to just duplicate the mesh part and flip it(works perfect) If I wanted that model called in via script, would there be any way of doing that? as a majority of my certain assets will be spawned in and controlled via script.(I’m terrible at scripting btw)

No, it’s not possible to flip the normals independent of vertex positions. For some special cases of exactly symmetric models, you can CFrame them inside out, but this is a hack that’s not officially supported or future-proof.

Preparing the model with extra faces for things like leaves is the correct way. You would not want the performance hit of disabling backface culling just to see the backside of some leaves here and there.

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