[Award Winner] Fun with Wilbur, Volume 1

[waldronate]

I was fiddling around a bit today and ended up with yet another forgettable terrain section like the one shown below.
http://www.ridgenet.net/~jslayton/Fu...ol1/index.html tells you how to make one like it in Wilbur.

[RobA]

Wow!

Thanks a lot for that. I have been playing with the erosion in Wilbur and was not happy with the geometric artifacts (straight lines) generated in the basin regions. Adding the noise was the missing step I needed!

-Rob A>

[su_liam]

That's looking like a place. Real nice.

[su_liam]

How would that work just adding a little high-frequency low amplitude perlin instead of uncorrelated noise to break up the flat basins? Would that be worthwhile?

[NeonKnight]

What I would REALLY like to see is a good:

FRACTAL TERRAINS to WILBUR and BACK tutorial.

I've played with the Erosion in Wilbur, and I don't know, it almost seems like it does more in Wilbur than it does in FT.

[waldronate]

How would that work just adding a little high-frequency low amplitude perlin instead of uncorrelated noise to break up the flat basins? Would that be worthwhile?

It should work just as well with one of the other noises as with the uncorrelated noise. The problem with relatively large basins will remain unless you use a noise of such high frequency that it's pretty much uncorrelated.

The primary reason to use the uncorrelated noise is that the basins are 1 pixel wide and so will not result in flat areas with straight erosion artifacts. The negative part of using the very high frequency noise is that the river tend to have a very high curvature, which sets a lower limit on plausible size of the map.

[loogie]

nice post.... i'm playing around with it and working on my DEM i made for editing in arcgis... (bryce and my past efforts have been lacking, especially in erosion)

[su_liam]

I see what you're saying there Waldron. Strangely, while I'm pretty well grounded in the math, I have a lot of trouble visualizing the results.

I'm curious is there any way to get a mask of basin areas from the Fill Basins filter? Failing that, and perhaps more generally useful, could you have a 'Select Flat' option. That is a selector that scans a window around each pixel(say 3x3) and selects that pixel if and only if all points within that window are within a given variation(epsilon?) of each other. Then you could noise up the supernaturally flat basins while leaving the yummy ridginess of the mountains pristine.

I wasn't initially sold on the terracing produced by the Remap Altitudes, but I like how the Precipiton mostly beats that down. It also erases a lot of the streambeds. Another thin Incise Flow at that point might be nice. (?)

Anyway this deserves a rep.

[RobA]

The magic wand can be used for selecting a basin. The tolerance is specified in actual height units (I think).

Here is the same example (except I applied an exponent to the height-field at one point) with the basins selected with the magic wand before applying the noise...


-Rob A>

[su_liam]

That sure is purdy RobA. It almost looks glacial. Somebody should point Monks at that. I'm not sure how much of that is the noise masking and how much is the exponent.

It looks like I'll have to fire up Wilbur after work tonight. I'm thinking about adding another Incise flow after the Precipiton stage. Hmm, I think I'd use an intermediate blend(maybe 1.0), a smaller amount(again, perhaps 1.0), the Flow Exponent and Effect Blend are a mystery to me, so that would need fiddling.