Can you invert the face normals of a figure?

Questions
1

So in my project I’ve been generating shapes via for loops, some of them generate the shape in a correct way and some doesn’t, so I want to know if there is any way to force Babylon.JS to calculate everytime the normals to the outside?

I wish I could give a playground but this time the shape is being generated from a json file and the playground didn’t let me put a tunnel to call that json.

This is the shape in question (ignore the lines), some of the shapes are with the correct normals but others are with inverted normals.

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image1325×628 65.9 KB

if is needed I can send code scripplets of the loop.

2

You could just copy and paste the json into the PG

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3

https://playground.babylonjs.com/#GI8Z7K

4

You can check VertexData.ComputeNormals: Create Custom Meshes From Scratch | Babylon.js Documentation (babylonjs.com)

Keep in mind that, for the normals to be correctly computed, the faces should be specified in the correct orientation: Counterclockwise in a Left Handed System.

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5

https://playground.babylonjs.com/#GI8Z7K#1
Look at lines 392-410. I have used this previously to determine winding order when using 2D clipping libraries supporting holes etc.

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6

Finally! thanks for the answer it really helped me a lot with the normals issue!

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