Interface And Graphics :: Performance Invalidating & Drawing A Lot

IGraphics and drawing and invalidating thing.I have improved, that I can tell. I won't explain everything, so here's the essential:Technically, my application will let you draw a rectangle on the form. You click, drag, and boom, a red rectangle is there. This rectangle will disappear when you start drawing another.I got that working.But my problem is performance. You see, obviously I have to update, invalidate and paint my rectangle every time the mouse moves while it is in "drawing mode". I do that every time the mouse's position changes.And that is quite a big deal. Every time the mouse's position changes? That's a lot of invalidations and redraws for a decently-sized rectangle!I thought of skipping some mouse movement, like only update every 5 coordinates moved or something. But that would render my goal quite inaccurate.I already invalidate only the regions necessary, that I can tell.