I got sidetracked working on #XResources support ... it all started from the wish that a child #widget should used its container's font when it doesn't have its own font configured (will be helpful e.g. for tooltips...)

Now I also integrated command-line overrides for resources in my XRdb resource database implementation, which is very cool. Actually, this system slightly reminds of CSS ... I can configure the looks of my #X11 application very flexibly!

Last thing I added was support for more formats to specify colors, plus querying the X server for named colors 😎.

#TIL: #XLib has some "color management" code and can parse and convert color specifications in different color spaces. 🤯 Ok, I don't want to link XLib (only #xcb), and I won't implement *this* myself, #RGB and #RGBA (together with "well-known" X11 color names) should really be all you ever need 🤪

https://github.com/Zirias/xmoji/blob/e342bd7612b9ce953849e2e8b374591d61c22d5b/src/bin/xmoji/colorset.c#L224

@thomasadam Adventures in #X11 #programming using #xcb ... I think I discovered some strange (and, undocumented?) behavior in #Xorg.

Getting more seemingly(!) "stray" Expose events, I finally discovered what's happening. I already decoupled my drawing logic from handling Expose, and instead maintain information in a widget whether it's visible and invalidated (with invalidation triggered by whatever, e.g. an Expose event). Only after processing a batch of input from the X server, I check whether a widget is both visible and invalidated, and if yes, draw it. So far a common pattern to avoid excessive drawing.

Now, setting the "root" widget (the window) visible as soon as a MapNotify is received, this *could* lead to start drawing before receiving the first Expose. Drawing still works perfectly fine, but this somehow delays the Expose event until something else "happens" to the window (like moving it), then you suddenly receive this Expose ... 🤯

Solution: Only set the window "visble" after the first Expose event is received...

I guess it would be impossible to trigger this with #Xlib because its API makes you wait for the response to every request... 😉