max "element" selection cache

Klunk

I've come across a strange issue with elements on meshes..... I was playing around with my own face detach routine as you do It all works fine and as expected but it seems max has "pre-cached" the faces that make up each element for the purposes of speeding up subobject element selection so after the detach when you use element select it still selects the entire mesh.... if you do a convert to mesh you can then select the seperated element... add any mod like mesh select and you can select the seperated element even if you add any mod and delete it you can select the new element. I've looked through the doc and can't find the function that clears this "cache". Anyone found a solution to this oddity ?


I detach the selection and then move it and enter element subobject mode and pick any face....

poopipe

Assuming the process is .. 
select faces, detach to element, move faces, select other element in element subobject mode.... 

I'm not getting it on max 2023 with editable poly or editable mesh objects or with edit-poly/ edit-mesh modifiers 
its the only version i have installed on this machine - what are you on?

Klunk

It's a custom sdk function not a default max action or script

poopipe

ah right - then i am no use to you at all

Klunk

you can replicate it with the attached script  after it's run goto element subobject selection and pick a face

Klunk

It appears to only occur when the mesh is in subobject edit mode when the detach is done.

Klunk

found the fix for the sdk function.... seems it's a thing with editable mesh interface i.e. when it's being edited so you have to enclose your code with....

MeshDeltaUser* mdu = (owner) ? GetMeshDeltaUserInterface(owner) : NULL;

if (mdu && mdu->Editing()) mdu->ExitCommandModes();

......
if(mdu)  mdu->LocalDataChanged(ALL_CHANNELS);

which forces the editable mesh interface to update it's shit, not sure how that would relate to the scripted version, probably just unselect it i guess 
just setting the subObjectLevel to zero before calling the detach does the trick.

the edit mesh doesn't cache the elements per se but does cache a face adjacency list which is then used to collect the elements during the pick mode...
and the MeshDeltaUser interface is the only way to invalidate the adjacency list