Some frames made transparent by default when using picom/compton

[lambdadog]

Alacritty and Firefox are two examples of windows that gain "frame transparency" when picom is running with default configuration. xterm and emacs are two examples of windows that do not.

(with default frame colors)

Transparency seems to be partially based on darkness of frame, perhaps?

I'm going to continue debugging this, but my first guess is that there's perhaps some property the frame should be setting that marks them "off limits", even if the window requests transparency (or whatever it is that firefox is doing that xterm isn't)? Or maybe something should be done when setting the background color, as the buttons (the entirety of the pixie Image it's drawn into, that is, including the portions where the window background color is drawn in) are unaffected.

[lambdadog]

This may be related to chjj/compton#162, given that worm uses XSetWindowBackground to set the color of frames, but it's unclear whether this only applies to the root window or not.

[lambdadog]

I believe what's happening here is that picom is assuming that you're using RGBA rather than RGB and

wormc frame-active-pixel $((16#FF161821))
wormc frame-inactive-pixel $((16#FF666666))
wormc border-active-pixel $((16#FF7499CC))
wormc border-inactive-pixel $((16#FF000000))

does in fact solve the issue.

I'm not sure whether the rest of the color values will accept RGBA, but I'll figure that out and submit a PR that changes the defaults and documentation to use RGBA.