Node Material normals flipped

[arobertson0]

Description of the problem

On the newest version of three.js, the normals as seen on the node material example are flipped.

This is what it looked like before the latest release:

After the release:

Three.js version

• Dev
• r108

Browser

• All of them
• Chrome
• Firefox
• Internet Explorer

OS

• All of them
• Android
• Windows
• macOS
• Linux
• iOS

[arobertson0]

@sunag could this be related to recent changes for clearcoat normals?

[sunag]

I think that It is because the pertubNormal2Arb in NodeMaterial was update, now pertub2.. result is diferentes with double-sided material. I am working for NodeMaterial get the core functions in runtime.

[Mugen87]

For testing (latest dev version)

https://raw.githack.com/mrdoob/three.js/dev/examples/webgl_materials_nodes.html

[sunag]

I still am not sure about change this, apparently with use node material and without NodeMaterial the result (MeshStandardNodeMaterial x MeshStandardMaterial) is the same? I have to test this with other sides to assure if this is really a bug or a not.

[sunag]

Maybe this is a bug of the function pertubNormal2Arb from the core?

[sunag]

https://raw.githack.com/sunag/three.js/dev-node-sides/examples/webgl_materials_nodes.html

#17584