setXYZ method
Sets the x, y and z components of the item at the given index.
Implementation
@override
InterleavedBufferAttribute setXYZ(int index, x, y, z) {
index = index * data!.stride + offset;
data!.array[index + 0] = x;
data!.array[index + 1] = y;
data!.array[index + 2] = z;
return this;
}