MeshData class Geometry

An isolate-transferable snapshot of a mesh's vertex and index data.

MeshData separates the CPU work of building a mesh (assembling vertex arrays and generating normals) from the GPU upload. Its construction is pure and touches no GPU resources, so it can run on a background isolate; the result is sent back and turned into a live mesh on the render isolate. This keeps heavy meshing, such as remeshing a voxel chunk, off the render isolate.

It is also the interchange type for reading geometry back and deriving new geometry from it: Geometry.extractMeshData produces one from a loaded mesh, and the pure derivation methods (unweld, extractEdges, merge) consume and produce them, so a whole derivation chain can run off the render isolate.

Recipe (using compute from package:flutter/foundation.dart):

// Top-level or static, runs on the background isolate.
MeshData buildChunk(ChunkInput input) {
  final positions = ...; // your generator
  final indices = ...;
  return MeshData.build(positions: positions, indices: indices);
}

// On the render isolate:
final data = await compute(buildChunk, input);
final geometry = MeshGeometry.fromMeshData(data);
// or, to update an existing updatable mesh in place:
existing.applyMeshData(data);