[Perf] Changing actor visibility should not compute actor matrix #3378
Description
High-level description
vtkActor.onModified triggers a computeMatrix(). This is useless:
- when only the actor visibility is changed
- because there is already a mechanism that computes the matrix each time it is accessed
Steps to reproduce
call vtkActor.setVisibility() and see that computeMatrix() is recomputing the matrix.
Detailed Current Behavior
too slow
Environment
master