Allow for partial I/O operations

[reczkok]

No description provided.

[iwoplaza]

Sparse/Partial write proposal

const Boid = struct({
  pos: vec2f,
  vel: vec2f,
});

const buffer = root.createBuffer(arrayOf(Boid, 100));

buffer.write(/* { pos: v2f, vel: v2f }[] */);
buffer.writePartial(/* Record<number, { pos?: v2f | undefined, vel?: v2f | undefined }> */);

// Updating only the position of the 5th boid.
buffer.writePartial({
  5: { pos: vec2f(1, 2) },
});