What kind of graphical oddities does this graphics pack avoid, and how does it avoid them?
Everything in DF relies on a simple code page (or "ASCII") tileset. These tiles are used and reused
everywhere, from menus to the map screen to the game. If you want barrels to look like little pixellated barrels, you also end up with screw pumps that look like barrels. This is so common among tilesets that I've seen fan artwork that depicts screw pumps
as barrels. They're not supposed to look like barrels, they just both happen to use the same tile. If you've ever looked around a DF map before embarking and wondered why towns look like backpacks, or wondered why dwarven settlements look like statues, or wondered why goblin camps look like bundles of cloth, or wondered why somebody put traps in the mountains, then you've run into this issue. There's official support for graphics sets, but they only work on living creatures. Worse, in adventure mode they only work on living creatures that are
in view of the adventurer. A dog may look like a dog, but if it dies, or it's an engraving of a dog, or you're in adventure mode and the dog is around the corner but still onscreen, it's back to being a 'd', not a nice little dog graphic. CLA cleverly makes all of its animals resemble their original letter, presumably because of this issue.
These are just a very small handful of the issues that come up: personally, they drove me insane when I started playing and I didn't understand why almost every tileset I ran into (including Tocky's tileset, the distant ancestor of my own work) had issues like these that nobody commented on. Fixing the graphical oddities that I encountered with Tocky's set is literally how my set got started. I suppose most users don't mind, or don't notice? Or the users that do mind just play "ASCII"? I'll watch Let's Plays and see screenshots, and I see weirdness everywhere. The world map--or the adventure mode map--make no sense in my opinion with many tilesets. (There's a "trap" to the north, a "backpack" to the west, and a "statue" to the east). Every set that doesn't mimic the vanilla ASCII exactly--or doesn't use TWBT--will have similar "issues". I avoid it by having every tile mean the same thing as the default tileset: if you see an icon, then it's more or less what Toady wanted to be there. Hopefully my version of the tile looks a little nicer. Note that none of this is the fault of the tileset artists, it's just fundamental limitations of the game. My set still has
some graphical issues, which are detailed in a text file in the download. These can be fixed by disabling graphics, and are DF bugs.
This hasn't been as big of an issue lately because the DF Starter Pack and some graphics sets use TWBT, a wonderful DFHack plugin. Many of these complaints have been fixed now, as far as I know. I still see oddities in various screenshots, but not as much as I used to. (As a side note, I think that my set would make a wonderful "TWBT font", but nobody seems to have thought of that. I should consider releasing such a plugin)
Apologies for the "mini rant", if I offended anybody. I don't mean to, it's just that I've been seeing confusing bugs for years now in many Reddit or 4chan screenshots and certainly in every Youtube Let's Play, but nobody seems to ever talk about it or express any confusion. Even when people describe why they prefer "ASCII", it's invariably "it lets me use my imagination more", not "there's no graphical weirdness" (the best reason to use ASCII or an ASCII look-alike set, in my opinion).
Considering the (small) conversation I had with Toady and Baughn about the graphics code, nothing official will be done about this anytime soon. Toady's happy reusing his code page graphics and the fans are happy with either TWBT or graphical glitches, if they even notice the presence of either. Hopefully one day Toady cleans up the official graphics code, fixes all of these issues, and lets tileset artists do things they currently can't (like draw a dwarf
on top of grass, not
instead of grass).
Completely incidentally, I recommend trying out my "dwarf letters" version of the tileset if you want consistency. If I didn't have many users it would be the only supported version. Without graphics enabled you get the most bug-free experience, and by having dwarves represented as letters and not smiley faces their graphics are consistent with every other species in the game.