[Lazarus] Getting update rect/region in Windows
Hans-Peter Diettrich
DrDiettrich1 at aol.com
Tue May 24 17:47:07 CEST 2011
Max Vlasov schrieb:
> tetris-inspired game and is gnu gpl. I would like to made it compatible
> with other platforms, but I'm not sure whether I should change
> region-based logic to something else in this case. I will be glad to
> hear any advice on this.
I don't know about concrete window managers, except for Windows, but IMO
there is little room for very different algorithms. A window (screen)
manager has to track modifications to a window (requiring repaint), and
has to take into account possibly overlapping windows, and widgets
inside the client area. In the simplest implementation all update and
clip regions are implemented as lists of rectangles. The only choice is
the implementation of clipping, which can be done by painting all update
rectangles in explicit (sequential) painting requests, or otherwise
leave clipping to the graphics library. In either case the paint
handlers have to deal with a single rectangular area (ClipRect), IMO.
DoDi
More information about the Lazarus
mailing list