Hans Goudey
89c7c115ce
Avoiding creating empty components can be a hassle for code that interacts with a geometry set. One easy way to do that was calling the functions that retrieved mutable access to geometry data directly, like get_mesh_for_write. This commit makes it so that sort of direct function does not create an empty component if there is no data. Another way to create an empty component was calling the replace_* methods with a null pointer. It's more convenient to have a nice API that handles those cases without creating an empty component. It's still convenient that the regular get_component_for_write adds the component if it doesn't exist, because that's often a nice way to add data to the geometry set. Differential Revision: https://developer.blender.org/D12862