feat(three): add Math bridge for Three

[krispya]

Adds a zero-copy bridge for Three while keeping the usual Object3D math interfaces like position, scale, rotation and quaternion synced. No patching, all userland code.

Basically, we take advantage of the fact that the Three Matrix4 are already array backed and directly copied for GPU buffers. We take this over and then replace the Object3D math objects with our own that access the Math tuples via getters and setters. This makes using Math path very fast with a small hit to perf (the cost of accessors) on the Object3D path. In hot paths we get a 1.4-2.7x speedup.

Workload	Vanilla three	math/three	Speedup
Instanced transforms, 10 000 instances	728 µs	318 µs	2.3×
Scene graph, 4 096 nodes (extend)	777 µs	331 µs	2.3×
Scene graph, 4 096 nodes (per-object mirror)	777 µs	284 µs	2.7×
Frustum culling, 4 096 meshes	293 µs	152 µs	1.9×
Vertex transform, 8 481 vertices	127 µs	59 µs	2.2×
Scene graph step + read every position/rotation	820 µs	606 µs	1.4×

The API uses a handle to get the Math tuples associated with the Object3D.

extend(scene);      // returns the scene math-backed
const t = transformOf(mesh);  // { position, rotation, scale, local, world }
vec3.set(t.position, x, y, z);      // the fast path

[changeset-bot]

⚠️ No Changeset found

Latest commit: 102c6f2

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

Click here to learn what changesets are, and how to add one.

Click here if you're a maintainer who wants to add a changeset to this PR