I'm developing a cloud of points viewer that allows user to select points with drawing on top of them a rectangle.
While drawing this rectange user can't manipulate cloud of points until rectangle is drawn and points are selected.
My problem is when there are many points in the field of view the FPS count while redrawing entire scene is very low and selecting desired points with a rectangle becomes difficult for a user.
What I want is to not have to redraw entire scene but keep cloud of points "frozen" - to be just background/layer for drawing rectangle on top of it.
I thought of some workarounds but I want to know first if there is not some OpenGL feature that supports just that.