Fixing incorrect normal map when using triplanar world mapping and mesh rotation

[RPicster]

Fixes #82311

On the original PRs (#82317) branch I unfortunately did a dumb move and it was faster moving the commit to a new branch. Sorry for the extra work @clayjohn @AThousandShips

This PR includes the feedback that @clayjohn gave on the original PR.

[clayjohn]

It looks like you missed my comment in the original PR.

For ease of reference, the correct code (for world space) is:

vec3 normal = MODEL_NORMAL_MATRIX * NORMAL;
TANGENT = vec3(0.0,0.0,-1.0) * abs(normal.x);
TANGENT+= vec3(1.0,0.0,0.0) * abs(normal.y);
TANGENT+= vec3(1.0,0.0,0.0) * abs(normal.z);
TANGENT = inverse(MODEL_NORMAL_MATRIX)* normalize(TANGENT);
BINORMAL = vec3(0.0,1.0,0.0) * abs(normal.x);
BINORMAL+= vec3(0.0,0.0,-1.0) * abs(normal.y);
BINORMAL+= vec3(0.0,1.0,0.0) * abs(normal.z);
BINORMAL = inverse(MODEL_NORMAL_MATRIX)* normalize(BINORMAL);

You can't rely on the post-multiplication trick like in this PR as it only works for planes.

[clayjohn]

Looks great to me!

[AThousandShips]

Can't speak for the functionality but the style looks good!

[RPicster]

Can't speak for the functionality but the style looks good!

This is a good point. I didn't even test the latest version.
Don't merge yet, I'll do some testing first 😅

[akien-mga]

Thanks!

[akien-mga]

Don't merge yet, I'll do some testing first 😅

Welp I didn't see this, just two approvals :)
You can mark PRs as drafts to prevent from merging them (and then turn them back to ready to review/merge once done).

[RPicster]

Don't merge yet, I'll do some testing first 😅

Welp I didn't see this, just two approvals :) You can mark PRs as drafts to prevent from merging them (and then turn them back to ready to review/merge once done).

Argh 🙈

But today is our lucky day! I just tested everything and it works perfectly ⭐