Are there resources around for people who want to start making tilesets for this game? Or should I start by hacking one? Which one?
Most of the time people start by modifying their favorite set. If you're a purist start with an ASCII (ASCII, Duerer, Wanderlust, Taffer etc.) it's the easiest to install/replace, as you don't need to modify the raws, or you can go for a graphic set, then I'd recommend Phoebus/Spacefox, they are almost identical in their raw modifications. The new kid on the block is
TWBT graphics: This dfhack plugin provides the most flexibility, but keep in mind that users will need to use dfhack load the set. The best/most complete TWBT set is
Gemset (though buildings/workshops are not complete yet.)
I'm making a colour palette. How many colours does DF support? DF Wiki talks about colour schemes in 16 colours.
But Spacefox has many, many colours in its art folder. This is confusing me.
16. I'm not sure what you mean by many colours in the art folder in Spacefox. Color information is stored in data/init/colors.txt, this tells the game what rgb value it should use for coloring the tiles with color defined. This is different from colors in the tilesheet. You may want to read how to use/abuse this with
Tile Magic.I'm a bit confused at the distinction of tileset and graphics set. Does the tileset just replace the ASCII characters and the graphics set does separate graphics for creatures and so on? So... do all graphics sets use a tileset also?
Yes. Yes. Graphic sets can use any number of spritesheets. I'm lazy, so let me quote BlackFlyme here.
Tilesets are images that the game uses to display the majority of non-creature objects, from terrain on the map to tools and numbers/letters. A tileset image is typically saved within data/art in the Dwarf Fortress directory, and the selection of the tileset is made within the init file.
Graphics are images stored within raw/graphics in the Dwarf Fortress directory. They are used to create images for creatures, and can include many different images for a single creature based on things such as their profession, whether they are a child or infant, or if they are an animated corpse. The definitions for these graphics are done in files that are also saved within raw/graphics.
How does the game apply a particular graphic from a graphics set to a creature, if it only has 100+ ASCII characters to choose from? Is there a piece of logic that says Hoary Marmot = this bit of a sprite sheet?
Tilesets are mapped by the files in raw/objects, and are limited by the ASCII sprites.
Graphics sets use their own configuration files and spritesheets. Check the raw/graphics folder to see how these look like. Only creature graphics are possible, for everything else you are limited by the main tileset. Except of course if you use twbt: then there's a 3rd configuration file in data/init/overrides.txt. Again, check Gemset for examples.
And... I see existing tilesets keep the letters a-z. Is this so that in-game text is rendered correctly? But I thought that TWBT did that, so can I use the full set of characters to make a tileset?
Yes, more or less.
And how do graphics sets integrate with TWBT, is that a prerequisite as well?
As mentioned above graphics use their own config files. Generally speaking creature graphics are not a problem, and they can work with or without twbt if the config file is written correctly.