I guess I should go into more detail about how I made the last map in gimp. At this point pretty much everyone who played or especially worked on last serb knows how cursed this knowledge really is, but wgen and its variants make the most boring maps imaginable and I'm really sick of playing on them. Just make sure to do lots of testing and double-check the colors in your biomes values.
I started with an IRL river that I grew up next to and wanted to capture the some of the feelings of. I found heightmaps of it, but I could tell just by looking at them they wouldn't work well in wurm. So I traced the outlines of the rivers and made up my own heightmap. Set gimp to grayscale 16-24 bit color,I forget which, single layer PNG. This is hard to work with if you're using a real thing as a basis, so you can just manually export one single layer at a time as you work. I suggest starting with not-quite-black and painting the rivers over it. You can mess with the opacity of your layers and your brush to get better views and softer edges. Do some google searching for "scatter brushes" or "dust/particle" and download some free ones, they're more useful for biomes but you can have fun in the heightmap too. Most IRL rivers flow through the low point between hills and mountains, and this one in particular is a bit south of a very famous gorge in the pacific northwest. Use high-opacity fuzzy edge brushes to make nice pale smudges beside your river, maybe leaving some space for floodplains or lowcountry (another place I lived near was a flat coastal marsh). Narrow and harden your brush over several passes and try to bring each mountain to a ridge or a line. IRL mountains are most commonly ridges like >>293860
, not singular pointy things with snow on top. Even then, they're usually much more rounded and less pointy. After lots of tests in-game (about 15 for the heightmap alone) I eventually used lots of blurring and smudging to make the terrain flow together more naturally, which took out some of the hard ridge shapes. I figured this was okay, mostly because I'd already spent like 15 hours on the heightmap and wanted to move on.
Painting biomes is even more cursed. One of the wgen variants I don't remember has an "import height map" button. The biomes map I included here is an early WIP version since I cleaned my desktop a few days ago and deleted most of my work without bothering to back it up first (oops). Most wgen programs can export a png of biomes when finished, and you can easily color-pick the stuff you want. There's also a forum post somewhere that has a huge list of every tile type and its RGB values. The pitfalls with this method are obvious, the colorcode for kelp is almost identical to grass, and somehow the two got mixed up in an early build like I mentioned in >>296134
. Another one was the birch tree / lavender bush issue. The forum post I found falsely listed a "generic bush" and "generic tree" color, which I assumed meant "put a tree/bush here and randomly generate which one later." I liked that idea, but also liked having some homogeneous forests and biomes, but ultimately failed to make a mixture. I wish I still had the finished biomes image we used, because you could clearly see that some biomes followed the shore and height very closely. This was deliberate, wgens usually include an "elevation map" too, much like what livemap uses on that setting. I opened one of these in gimp, put it underneath my WIP biomes image, and used fuzzy select around the conveniently-placed elevation demarcation lines for most of the biomes I painted. For trees and bushes I used free scatter-powder brushes like mentioned earlier.
Once you've done this, plug your heightmap into a wgen program, drop your dirt, then import your biomes file confident that fucking up at this stage might only cost you as little as 30 seconds of time. Or more, if you do the kelp thing too.
Oh, and certain things like clay and tar are much better placed with the wgen tool, or in-game. I sincerely hope some of you use this knowledge better than I did and add to it, something that desperately needs researching is hand-painting the cave layer.
Anyone want to know anything else, or just want to point and laugh at the guy who spent weeks >painting maps in gimp