I'll try that...
Nothing doing. The sliders keep moving and don't give me a choice. The granularity of the expected number of volcanos just doesn't allow for it on this size of map (257x129, 99% = 331 squares. 100% = 0 squares. No middle ground).
So my choices are either to use the in-game painter (ugh) or paint 331 volcanos into the map, then hack the game to make sure it generates them all, so I can be sure that the volcanos I paint actually show up, leading to a very very very volcanic map.
In a pocket region it might be possible (1% of 17x17 = ~2.5 square granularity... so there would still need to be extra volcanoes painted in that situation), but on this map it's just not going to work.
I know the map data itself can support any specific values and be understood by DF. Possibly I could intentionally paint 200+ "fake volcanoes" with 0.99 as their specific value, then Find+Replace that with 0 or something when importing the data... but it seems a very hackish way to get things done. Ultimately it may be what I need to do...
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Well, here is a needed feature. Very simple too Ceph.
A [CLEAR] button.
Some way to erase all information and clear everything back to null without closing the program and re-doing all the other maps to get what you need on the one screen you just need to clear out.
I know I ask for a lot, but this program is amazing and there are just some things that I can't do with it, even tho I know they're very possible (like telling the program not to "bend" the output to fit some kind of expected percentage, as an option, or adding a button to clear the whole tab out without wiping out any of the other data).
((EDIT: Nope, this won't work either. The slider sets the amount of squares that will be exported with a value of "100" exactly, letting them be volcanos. If PWDF thinks they're volcanos there seems to be no way to trick it into exporting them as any other value.)
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Also, the paint functionality isn't "buggy" unless I use the Large Smoothing brush and push those percentage sliders beyond the breaking point. Using the point brush works fine, every time, but once it goes past a threshold it annoyingly moves a slider or otherwise "bends" the output to fit the percentage sliders again. This is what I was running into with the volcanos.
I'd have all the volcanos painted on there as 1x1 boxes, in precisely the area I'd want them, then once I passed a threshold (99% below volcano, 331 count on a 257x129 map), !!BOOM!! All of a sudden the slider moved and I have thousands of volcanos, which once were Igneous Extrusive layers (seems it grabbed the next closest value for the volcanos, and since there was nothing between 0.7 - 1.0, it said all of that range was 100% volcano territory). Then the program freaks out and turns the slider up again sometimes, meaning that there were NO volcanos.