Three.js: Proposal: Add new BufferAttribute methods

[WestLangley]

Vector3 has these methods:

Vector3.applyMatrix3( matrix3 );
Vector3.applyNormalMatrix( matrix3 );
Vector3.applyMatrix4( matrix4 );
Vector3.transformDirection( matrix4 );

We need to be able to apply the same transforms to each element of a BufferAttribute.

I propose we add the following methods:

BufferAtribute.applyMatrix3( matrix3 );       // to replace Matrix3.applyToBufferAttribute()
BufferAtribute.applyNormalMatrix( matrix3 );  // new
BufferAtribute.applyMatrix4( matrix4 );       // to replace Matrix4.applyToBufferAttribute()
BufferAtribute.transformDirection( matrix4 ); // new

Related:

17997

18001 bug

18005 bug

Suggestions for alternate APIs welcome.

[mrdoob]

transformDirection() > applyDirectionMatrix()?

[WestLangley]

transformDirection() > applyDirectionMatrix()

transformDirection() is applying a transform to the vector, but interpreting the vector not as a position vector, but as a direction vector. That method was introduces a long time ago and I think the name is OK.

[WestLangley]

I never liked the API

matrix.applyToBufferAttribute( attribute );

and this is an opportunity to replace it with an API that is, in my opinion, more natural.

[mrdoob]

Moving them to BufferAttribute sounds good to me. Was just trying to unify the last name.

[Mugen87]

Moving them to BufferAttribute sounds good to me.

👍

[WestLangley]

OK, I'll do it.

[WestLangley]

Closed in #18070.