Hey folks, I know we have Mesh.flipFaces(true) working on meshes to flip faces and normals. On material we have sideOrientation to doing similar things but this feature doesn’t flip normals at all. Just wondering is there a similar function but only filp normals on material end? Or at least flip …

Here it is: Babylon.js Playground Babylon.js playground is a live editor for Babylon.js WebGL 3D scenes

No, there’s no existing option to just negate the normal in the shader code. What is your use case for this? What you can do is to create a material plugin and negate vNormalW at the CUSTOM_VERTEX_UPDATE_WORLDPOS injection point.

@Evgeni_Popov Thank you for the response! Can you provide a PG for this material plug in? I actually asked a follow up question here 1 day ago: [image] Make an imported mesh double sided and apply two materials Questions Thank you very much! I would rather not admit how …

You can enable two sided lighting and disable back face culling. This way, you don’t need to call makeGeometryUnique: Babylon.js Playground Babylon.js playground is a live editor for Babylon.js WebGL 3D scenes Using a material plugin, you can avoid cloning …

@Evgeni_Popov Thank you for the PGs! Actually can you give me an example of Material plug in that only flip normal at render time? I know I can use twoSidedLighting but ran into some issues when I use it in practice. So for my case just trying to find a way enabling the material to flip normal at…

@Evgeni_Popov Yes!! that’s it! And its awesome it works for both PBR and Standard materials! Thank you so much again!

@Evgeni_Popov @sebavan Btw do you guys think this function it’s worth to be promoted to an official feature?

This sounds really edge case to be a general feature and easy enough to deploy as part of the app itself. Let s integrate as soon as it gets more traction.

Simple solution to flip normals on materials?

Questions

Evgeni_Popov September 18, 2023, 7:43am 6

Here it is:

Make an imported mesh double sided and apply two materials

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Simple solution to flip normals on materials?

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