(15-05-2020, 02:47 AM)venam Wrote: In sum, windows and pixmap are instances of something more abstract called a drawable. The difference is that a window is something on the screen already while a pixmap only lives in a memory buffer. You can then apply the pixmap pixels over some other drawables.

Thanks venam! Your post was very informative. I bookmarked it here for the links in the references.
I will check the other linked posts on your blog either. They might come in handy when I venture in the task of creating my own window manager, the next project I want to do in order to learn more Xlib.

(15-05-2020, 09:49 AM)vain Wrote: ... and one of the main reasons why anyone would want to draw into a pixmap and then copy it to a window is: Double buffering. When you do a lot of drawing operations directly onto a window, it can happen that you see glitches, artifacts, flickering. Even on today's brutally fast machines. So, you first draw an entire frame into a pixmap and then copy the final result to a window. It'll be smoother.

I was indeed experiencing some flickering on the windows of my menus while remapping them. I solved it by improving the algorithm that decides when to remap stack of menus to it preform less remapping.
I will rewrite the code to use a pixmap for each window.