ZDoom

The recent renderer overhauls seem to have knocked these console commands into disuse.

Fire up any old game/mod/map, whathaveyou, bring down the console, type "test[color/fade] red" or "test[color/fade] "ff 00 00"" and you'll get no results.

Can't say for certain when this was introduced but this is present in both QZDoom (1.4.0) and GZDoom (3.0.0) - I would guess it's been this way for awhile.

Did those work only in the software renderer or also in GL renderer?

I'm pretty sure they used to work in GL.

Yes, they did.

I fixed this in the software renderer. However, due to the way colormaps were moved to be handled internally by the software renderer, I'm not sure how to do an easy fix in the GL renderer. Essentially the CCMDs are changing internal variables that the GL renderer no longer depends upon.

I suppose that I will use an older version to mod with until it is fixed

This was a classic case of a gross hack that was convenient but depended on an implementation that ultimately blocked certain editing features - the refactor was done to allow defining per-sector colors for walls, flats and sprites and handle them in the software renderer. The old colormap feature constantly stood in the way of making lighting more flexible and the test CCMDs depended on some idiosyncrasies of how the engine stored colors as colormaps, not as RGB values.

Of course this can be added to the GL renderer again, but it involves adding a check for each single element that gets rendered and, while not really expensive, would add some overhead only to suppoer a rarely used test feature - if you do it once it won't be an issue, but imagine 10 of such features starting to pile up.

Putting on hold because I really do not want to litter the core rendering functions with this baggage.