Allow setting label color and background defaults

[olibclarke@…]

• The default label style used when using the “label” mouse mode vs the

“zone” mouse mode is different. The “label” mouse mode defaults to black
text (or white text if the background is black), while the “zone” mode
defaults to yellow text, on a black boxed background. The “zone” labels in
my opinion are much more readable, particularly when zoomed out a bit -
the opaque box background helps a lot with visibility in the context of a
complex structure. Is there any reason why both modes couldn’t use the
same label style? Perhaps for distances also?

Or maybe just let users configure some default global display preferences
in the “Labels” section of preferences - font (+color+scale in Å/px),
background (yes/no/color/transparency), etc, and then have these apply by
default to all labels.

Cheers
Oli

[Tom Goddard]

It would be nice to be able to choose the label defaults in ChimeraX preferences and also with a "label defaults" command.

I made the zone mouse mode use yellow text and a black background because my initial uses of it were in virtual reality and the solid background and yellow color were especially necessary with that kind of display. Transparent background makes the letters look like worms floating in space in VR. I agree it has some merit for viewing on conventional displays too. But it is unclear what the best default is and so allowing the user to choose the default is reasonable.