Can anyone share settings/process for using the erosion features of Wilbur? I've been playing with it, but the documentation doesn't load so I'm stumbling in the dark.
I've been working through some of them, and I get some weird results. Mainly around the Incise Flow. One tutorial says to add noise after filling basins, and I have seen why that is needed (straight rivers, anyone?). Problem is, the 5% noise makes the mountains and deeper oceans look lumpy and spotty.
Have you (or anyone else) ever experienced this? If so, how'd you fix or avoid this?
Your image has the weird pitted appearance that you can get if you do incise flow without a fill basins step right before it. I recommend doing basin fill/noise/basin fill in sequence before incise flow because that second basin fill reconnects all of the rivers that were chopped into little pieces by the noise. I also recommend doing just a little precipiton erosion after an incise operation because the raw incise flow operation does a number of hydrologically implausible things to the surface. They results look plausible, but the raw incise tool leaves a definite mark behind.
Wilbur has several kinds of noise. It's unlikely that you'd ever want to use percentage noise for this type of processing, because it adds a random percentage of each altitude to that altitude (things farther away from zero get more noise, making mountains noisier than plains). For normal river processing, you want the same amount of noise everywhere (possibly you'd want a little less on the mountains, but Wilbur doesn't have a filter to directly do that). What you probably want to do is use Filter>>Noise>>Absolute Magnitude Noise with a value that's about 5% of your current maximum altitude. You can get your maximum altitude using Surface>>Find Min/Max and reading the "Highest" value on that dialog.
Wouldn't be the first time that I said something, then figured out a better way. I'll to remember to fix that tutorial, but I don't know when (or if) I'll get back to documentation.
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You can download a few tutorials from the bottom of this page here:
http://www.fracterra.com/wilbur.html
There are also several tutorials that include information about how to use Wilbur with FT3 in the community blog (tab at the top of this forum)
I've been working through some of them, and I get some weird results. Mainly around the Incise Flow. One tutorial says to add noise after filling basins, and I have seen why that is needed (straight rivers, anyone?). Problem is, the 5% noise makes the mountains and deeper oceans look lumpy and spotty.
Have you (or anyone else) ever experienced this? If so, how'd you fix or avoid this?
Wilbur has several kinds of noise. It's unlikely that you'd ever want to use percentage noise for this type of processing, because it adds a random percentage of each altitude to that altitude (things farther away from zero get more noise, making mountains noisier than plains). For normal river processing, you want the same amount of noise everywhere (possibly you'd want a little less on the mountains, but Wilbur doesn't have a filter to directly do that). What you probably want to do is use Filter>>Noise>>Absolute Magnitude Noise with a value that's about 5% of your current maximum altitude. You can get your maximum altitude using Surface>>Find Min/Max and reading the "Highest" value on that dialog.
In addition to the tutorials at the fracterra site, there are some at https://www.cartographersguild.com/showthread.php?t=29412 if you're willing to trudge through the silly discussion.
Thanks for the advice. I'll give that a try.
Couple of points though:
1- I did do a fill basins before the incise flow.
2- Your tutorial at http://www.fracterra.com/FunWithWilburVol1/index.html instructs users to perform a Percentage Noise operation.