selectVariant method

bool selectVariant(String? name)

Dresses every part in its material for the variant called name, or in its default material when name is null.

A part the variant does not mention wears its default, which is what KHR_materials_variants says. Returns false, changing nothing, when no variant has that name.

Switching changes which material each mesh node points at, never the materials themselves, so two instances sharing the asset's materials can still wear two variants at once.

Implementation

bool selectVariant(String? name) {
  final index = name == null ? -1 : variants.indexOf(name);
  if (name != null && index < 0) return false;
  for (final (mesh, part) in _drawn) {
    mesh.material = _materialFor(
      part.variantMaterials[index] ?? part.material,
    );
  }
  _variant = name;
  return true;
}