Global math tool in Fractal Terrains Pro

kc1974

I downloaded the demo of Fractal Terrains Pro after using CC2 for many years.

Playing around with it, I feel like it needs to have more tools than it does. Most importantly, the Global Math Tool seems to almost never work. I am trying to create more realistic elevation distributions but raising the offset to an exponent, but when I run it, it just refreshes the map with no changes. I've used Wilbur and feel like there are some things Wilbur does - like the exponential tool - that FT can't do well, which is frustrating. I really like the idea of the product and would like to buy it, but I'm hesitant because it doesn't seem to be quite right. Any advice?

jslayton

In Wilbur there is only a single value for elevation. This value can be computed and processed in a number of ways. This style of editing, however, limits the zoom level on the map. FT, on the other hand, generates its images dynamically from a fractal function, two offsets, and a scale according to the relation altitude=offset+roughness*(fractal+prescaleoffset). If you haven't modified the offset channel then math operations won't have much effect upon the result. You can force FT to treat altitudes in the same way that Wilbur does (including all of the resolution limits) by moving the altitude result to the offset channel using Tools>>Actions>>Burn In To Surface.

FT automatically does exponentiation as part of its processing - it's how the continental shelf feature is implemented. If you'd like to adjust the exponetiation constants for continental shelves to other than the default 1.75 and 0.6 (above shelf/below shelf values) then you can edit the srf file directly. Open the srf file in notepad and look for the line that reads "Misc 1.75000, 0.60000, 0, 0, 1" and modify the first two parameters to your desired values. Load the modified srf file and you'll have the exponentiation values that you're after.

kc1974

Thanks... I can get it to work after burning it in. I didn't realize that I needed to do that.

However, when I did it, everything below sea level turned black and set to altitude and rainfall levels of "-1.$ ft". I've also had this problem with some of the color-to-altitude conversions I've done, too. I assume that's some sort of error value.

kc1974

Let me revise what I said - what I did there was run the math tool.

Now I've altered the srf file and loaded it in, but I can't get it to really generate anything close to realistic relative heights. The problem for me is that when I have it set to a max peak of 30,00 feet, which is reasonable, rather than have an exponential distribution with very few places actually approaching that height, the vast majority of the planetary surface seems to be too far above sea level. The actual elevation distribution should look like this: http://www.nationmaster.com/encyclopedia/Image:Earth-elevation-histogram-2.svg

I can't find a histogram in FT (which is something I like in Wilbur), but I'm sure the distribution doesn't look much like that. I was hoping to use exponentiation to create a higher percentage of lowlands, but I can't seem to get it to do that.

Any advice would be much appreciated. I am really loving the demo so far (after 2 days) but it's hard for me to justify buying it if I'm mostly going to go back to Wilbur to create the landmasses. I wish I could combine the best elements of both programs, since there is so much more you can actually do with this.

jslayton

If you're familiar with the Remap Altitudes tool in Wilbur you will find this tool in the release version of FT (2.3.0.10). The demo version of FT is only version 2.2 so it's lacking some features of the updated retail version.

The -1.$ problem occurs when an infinity is encountered. There is currently no way to fix those values when they occur in FT.

FT and Wilbur serve different audiences. http://www.ridgenet.net/~jslayton/wilburvft.pdf has a (somewhat dated) description of the major differences between the products.

kc1974

Thanks for all the help.

I think I'll probably wind up buying it. Though it has its flaws (why doesn't it ever seem to generate deserts, for instance?), it's a nice program that makes map editing on a true sphere much easier.

jslayton

It will generate deserts if you play with the rainfall and temperature a bit. The climate rules are based on average rainfall and temperature from a static climate model according the table below. The static model in FT doesn't take into account wind or ocean current effects.

brutus

hi jslayton: i have a question to you: where i can see on this nice graphic map, for example, to change the climate values, if i start Fractal Terrains 3?? Are this possible?

jslayton

I'm not sure that I understand your question. The table shown above is the internal map from rainfall and temperature to climate type. Because the table is internal to the software, you can't change it. You can change the colors associated with each climate type by using the Map>>Lighting and Color command and then selecting the Climate tab.

You can also do a direct color mapping of rainfall vs temperature using the Map>>Show Image Climate tool. The default coloring map shown is basically the above table, but turned upside-down because the temperatures start at the upper-left in the Image Climate tool and in the lower left in the above image.

A relative of the climate coloring that I mentioned first is the textured climate setup operation (Map>>Show Textured Climate in the software). Instead of selecting a solid color for a climate type, you select a picture to tile onto the climate areas.

I had considered having an indirect mapping that used an image climate-type stage for the first mapping and a textured climate stage for the second mapping, but I felt that people would probably be utterly baffled by it.