Elevation XIII: The Uplifting II: Return of the Uplift

So let's examine some of the intermediate output. The full blended map is a little hard to process, so I'll crack it apart:

C

T

D

So there is very heavy C+T concentration in a few areas, and essentially flat elsewhere. Same with D, but at least its not in the same spots.

While IDW gives a nice smooth interpolation, I want it to be a bit spikier. The top-left continent should have a small C band running across it, yet this is smoothed all the way out (with small whiter patches where T is dominant).

The problem with IDW is that it does not know that the value is supposed to drop off from the actual fault line. Instead, it's a smooth interpolation. Which is good for many other things, but might be a bad design choice here.

What about a multi-modal Gaussian? I could determine the distance to the different peaks, have a controllable drop-off, and then sum it all together to get a nice smooth distribution.

Much better. I could improve a few things, of course. The simulation takes a long time to run still, but that has more to do with the distance calculation - I have to calculate every hex's distance from every other hex.

So the uplift becomes:

This uses $c=1.0, t=0.5, d=-0.3$ for weighting factors, with an additional gamma correction of $\gamma=5$. Gamma correction is common in photomanipulation, but if you want to do it by hand, use this formula:

\[x' = x^{1/\gamma}\]

Where $x$ is your scalar between 0 and 1. This adjusts where the "average" greyscale value is, and can therefore be useful if an image is too bright or dark, while maintaining the 0-1 scale. All in all, there's a nice Fresnel effect going on here.

A niggling thought has entered my mind that I should do like everyone else and build coastlines from the ground up terrain generation. We'll see how things go...it's very tempting. A lot of the highest uplift here is beneath the sea! And many divergent boundaries cross the land (which isn't wrong, but uncommon).