Vanilla: entries 128 to 255 of the color table

[backwardsEric]

In Vanilla, using a color index between 128 and 255 for a grid is going to trigger Windows, SDL, SDL2, or Mac front ends to try and render that grid with the front end's pict_hook (i.e. as a graphical tile). Are those entries there so the text-only front ends (GCU, X11, Nintendo) can use them? Or is there another rationale for those entries?

I'm tempted to cut the color table size to 128 (and adjust how the same/hybrid background options are implemented since those are tied to MAX_COLORS).

[smbhax]

Does anything use a color table entry higher than 28?

[backwardsEric]

As far as I know, the data files only use the first 27 colors and the code has named constants (well preprocessor macros) for the first 28. The preference files do allow color assignments from the full range of the table to features, monsters, and objects.

[Nick]

In Vanilla, using a color index between 128 and 255 for a grid is going to trigger Windows, SDL, SDL2, or Mac front ends to try and render that grid with the front end's pict_hook (i.e. as a graphical tile). Are those entries there so the text-only front ends (GCU, X11, Nintendo) can use them? Or is there another rationale for those entries?

The only thing I know of is that NPP (and other variants that copied it) introduced a wider variety of colours by adding shades of the basic (then) 16. IIRC this was used as the basis for adding the new V colours 17-27. 28 was introduced for doing Sil-style shading of monsters and hybrid walls, and FA has a 29 originally for the trap detection line in wilderness, I think.

So I think your plan is fine.