Maya API: MSelectionList::getSelectionStrings() - Getting a flattened list?

Coding
#1

Question about the MSelectionList object in Maya API.
I see that the getSelectionStrings() function returns selection on the format of pCube1.vtx[0:7] instead of a flattened list which you can get via maya.cmds.ls(flatten=True). Is there any smart way around this?

Problem I have with this is that you can’t really loop thru a component selection (without getting the DAG-path and running a mesh iterator on the entire mesh - which will go through ALL the components if I am not mistaken?) I want an easy way of storing partial component selections and the ability to loop thru these at a later stage.

I tried doing maya.cmds.ls(selectionList.getSelectionStrings(), flatten=True) but ran into some performance problems (100k vertices) where it would lag for several seconds. I also tried making my own flattened string list using regular expressions (which was 5x faster but still slow). It feels like I’m fighting this from the wrong end here.

#2

Okay so I found this:

Code from the blog post:

sel = OpenMaya.MGlobal.getActiveSelectionList()
__, vertices = sel.getComponent(0)
fn_vertices = OpenMaya.MFnSingleIndexedComponent(vertices)
vertex_indices = fn_vertices.getElements()

So getComponent(index) will return the DAG path and an MObject of the components - in this case vertices.
Then you can create a function set for retrieving the indices.

PROBLEM is multi-selections. The MObject that getComponent(index) return only holds data about the FIRST component type you selected. Running apiTypeStr() on it will return “kMeshPolygonComponent”, “kMeshVertComponent”, “kMeshVtxFaceComponent” - whatever thing that was first selected. This is not what I expected. :frowning:

#3

Ok problem solved.
MSelectionList is limited. But MItSelectionList can be used for iterating over multiple component types.

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