The Rugged Realm -- Realistic Topo

[Peter Toth]

Hello Guild,

Thank you so much for your critiques which were integral to my growth as a fantasy cartographer. I've lately modified my ambitions: No longer actively seeking commission, I now prefer to simply do what I love and cheerfully accept whatever fate may befall me.

I know that these atlas-style pieces aren't everyone's cup of tea, but I find them a better tool to help me visualize the continent of my dreams, which I plan to start sculpting, once I've learned how to render realistic topography.

This piece was created using GIMP and Wilbur.

Let me know what you think.

FinalProj.png

[Tiana]

The results are pretty amazing though, well done.

[Eowyn Cwper]

This is wonderful! I couldn't dream of a better topographic style. My eyes just get caught by that great Valley in the northwestern part. It isn't clear to me where the drainage divide is with the one below it.

[QED42]

Fantastic! I might have said this before but I hope you plan on putting up a tutorial on your method once you have perfected it.

[waldronate]

It's looking better. You've overcome most of the straight-line artifacts, which are usually the hardest part of using Wilbur. You've also done a good job on getting rid of the mostly-parallel rivers. There's one another Wilbur artifact that shows up in this map, but much reduced from your earlier efforts: the crow's foot. This feature results from basin fill operations making a large nearly-flat area with a single outlet and then incise flow making the radial nature of the rivers apparent. This sort of feature doesn't occur in Earth topography (except as a very transient feature in dammed rivers when the dam breaks and never as a very large feature) because stream capture never allows many feeders to dump through a central point.

The way to overcome the crow's foot artifact is to avoid large flat areas in the first place (which means that you shouldn't have bowls that get filled up during the basin fill stage). You might be able to draw a selection around the bowl at its initial filling and do incise flow, but reduce the exponent until there are a minimum number of channels, then use precipiton erosion to break down the flat areas. You can also manually break the exit dam by painting it down a bit. You can find problematic areas using Surface>>Fill>>Compute Basin Deltas. Big areas will show up as lakes and you can work from there. If you'd rather not recompute the surface to see your deltas, you can get that same sort of information by changing the direction of you light to point straight down on your surface (For the default Wilbur shader, using Texture>>Shader Setup, pick the Intensity tab, then set Vertical Exaggeration to 10 (or 100), and Elevation to 90). The flat areas will show up as bright, while sloped areas will show up darker: the larger your vertical exaggeration, the darker slopes will appear. If you use a very large vertical exaggeration (10000 or so), then you can see the slopes added by the default Fill Basins operation. That -1 value on Fill Basins is a cheat to have the system compute a useful value for you. You can also directly enter a value to get interesting effects. Using a value of 0 will give you completely flat basin fills that incise flow wont' do anything to. Running some precipiton erosion on that completely flat area before the noise/incise flow may also be a way to reduce the crow's foot artifacting.

[Peter Toth]

Thank you all for the kind words and support. I haven't exactly figured out the drainage area demarcations or any plausibility details yet... this is merely an experiment in rendering topography. I'm eventually going to incorporate all your feedback to help me create the world of my dreams, which I will even calculate the interior of (proportions of olivine/pyroxene, size of iron sulfide core, etc.) using hard physics equations (another digression of learning from that ol' physics book). I'm hoping to account for every physical detail, which I know is quite ambitious for a person like me. Yes, QED42, I do intend to publish a tutorial on my exact process sometime soon, once I've finalized and refined it. I'm still experimenting using the tools available to me, so expect many failures to crop up in future contributions. Ultimately, I learn through your constructive criticism, so keep it coming. By the way, Waldronate, could you recommend a book that explains cartography concepts and terminology, as I'm very interested in learning. I understand basic geology but haven't specialized at all in subjects such as geomorphology. Thank you all for your interest in my work.

[waldronate]

By the way, Waldronate, could you recommend a book that explains cartography concepts and terminology, as I'm very interested in learning. I understand basic geology but haven't specialized at all in subjects such as geomorphology.

I'm not sure exactly what level of book would be helpful, but starting with an internet search for "introduction to cartography" will get you some articles and blogs, many of which have some very nice bibliographies. I can't be more specific than that, though, because it's been many years since I did much in the way of fundamentals and most of that was from journal articles and other such things way back in the depths of time.