Converting a map from World Builder to Wilbur

[masdog]

Thanks to another post on this board, I found out about World Builder. I've been playing with the software, but I don't like the climate model that it generated after reading the Climate Cookbook. I'd like to import it into Fractal Terrains to see if it generates a better climate model, or baring that, a decent altitude map that I can bring into Photoshop to generate my own climate model. Everything I've seen shows that I need to bring the map into Wilbur before importing it into Fractal Terrains.

Unfortunately, I can bring the file into Wilbur, but I can't figure out how to generate an actual sea-floor or bump up the terrain to match the roughness that shows up in World Builder. It also comes in very blocky. Is there a good tutorial that explains how to do it? Does anyone have any tips for adjusting the height field?

I've included the output from World Builder.

[hohum]

Because you don't have any sea data in the original image it may be hard. I have struggled with this myself. The other thing that can be difficult is retaining your coastlines if you can't figure out your sea level in Wilbur. What you might do is paint your own sea floor dem with the brushes from here. This is actually the DEM tutorial, but the brushes link is in the first paragraph or so. Good Luck.

[waldronate]

In the grayscale BMP you posted it looks like your sea level is at 22 and the maximum altitude is at 217. The blockiness of the terrain is a feature of World Builder.

Assuming that the spectral color scheme is the output from WB, it is exactly the same as the grayscale heightfield in the second image in terms of image content. Your eye/brain combination is better able to interpret the gray ramp as it is more sensitive to the intensity changes than to the smooth color changes.

A little processing with Wilbur can get some kind of results, but the ocean floor is probably not going to ever turn out really well.

[masdog]

Wow! Thank you, Waldonate! That's very impressive. What steps did you take to turn my world builder output into that amazing map, if I may ask?

[waldronate]

It pretty much follows the steps in http://www.ridgenet.net/~jslayton/CGTutorial/ as far as the land processing went. The general technique is:

Load the HF bmp.
Lower the land to get the coastline correct (Filter>>Mathematical>>Offset with -22 as the value).

Select the land areas (Select>>From Terrain>>Height Range with Min=0 and Max=100000)

Then repeat as often as desired:
1 ) Filter>>Noise>>Absolute Magnitude noise with a value of about 5
2 ) Filter>>Fill>>Fill Basins to fill the little pits and let incise flow work
3 ) Filter>>Erosion>>Incise Flow with blur amount=2 and blur=2 to get river channels
4 ) Filter>>Erosion>>Precipiton-Based
5 ) Filter>>Height Clip with land selected and min=0 and max=10000
6 ) Select>>Inverse to select the sea
7 ) Filter>>Height Clip with sea selected and min=-10000 and max=-0.001
8 ) Select>>Inverse to select the land again

The undersea parts were equally simple.

a ) Select>>From Terrain>>Height Range with Min=-10000 and Max=0 to select the sea.
b ) Filter>>Fill>>Mound with min=0, max=-10, and operation=add to get the basic channel shapes moving away from the land.
c ) Select>>Deselect to stop using the selection for a bit
d ) Filter>>Noise>>Absolute Magnitude noise with a value of about 5
e ) Filter>>Fill>>Fill Basins to fill the little pits and let incise flow work
f ) Filter>>Erosion>>Incise Flow with blur amount=2 and blur=2 to get river channels
g ) Filter>>Erosion>>Precipiton-Based and use the defaults
h ) Select>>Reselect to restore the sea selection
i ) Filter>>Height Clip with sea selected and min=-10000 and max=-0.001
j ) Select>>Inverse to select the land
k ) Filter>>Height Clip with land selected and min=0 and max=10000

The important parts here are steps 5-8 and h-k because they enforce the basic landform shapes in the face of ongoing noise distortion. The absolute magnitude noise will turn the coastlines into fairy dust without them.

One of these years I need to do scripting for Wilbur to simplify these types of things. On the plus side, I did come across and fix a bug with the Wilbur shader that was preventing the opacity feature from working correctly. I had intended to do something like the attachment (resolution was bumped up a little, too).

[masdog]

Thank you for the general process, Waldronate. I've started to play around with my world, and it's amazing the changes I can make. I'm curious, though. What is the reason for running Precipitation Erosion after running Incise Flow. It seems to wipe out any narrow, easy to follow rivers and replace them with a wide channels.

How hard would it be to create something similar to the Actions Palette in Photoshop that allows you to create macros from frequently repeated actions?

[waldronate]

Incise Flow has a tendency to leave little basins and Add Noise has a tendency to leave little altitude pimples. Precipiton erosion will tend to smooth out the pimple and fill the basins as well as reducing some of the effects of the very steep canyon walls that occur during incise flow. If you look at a 3D view of the terrain, those nice little canyons that Incise flow generates with small blur values would correspond to incredibly deep gorges in the real world. The second image I posted uses the Texture>>Other Maps>>River Flow feature to put rivers in the image without disturbing the underlying terrain.

As far as the actions palette thing goes, it requires an infrastructure where each command places its parameters into a structure which can be stored. This change is fairly simple on a per-case basis, but there are many, many cases. Each action in Photoshop is effectively a simple declarative script in most other programs. When I set out to implement the feature in Wilbur my estimate was that it would take roughly 7 weeks of effort to accomplish. In short, an awful lot of effort to expend when I'm chronically short of free time and motivation these days.