Ridgetop Rivers

I’m not sure if this is a bug, or just an unfortunate feature, but I ran into a problem following the Alpine Lakes example terrain where the water creation is done before the erosion. I had not added any lakes to my layout generator, doing a quick test of eroding into the created tributaries. What I ended up with was terrain eroded below the water level in places which resulted in streams running on top of ridges.

This sort of prompts a feature request, hoping that future versions of WM will lower the terrain while preserving the water channels at the erosion level.

Just an afterthought, the idea for what I was working on was to add a lake to an existing terrain, where the erosion would flow into the lake and rivers. Originally, I did my flow restructure and create water after my erosion, ending up with rivers at the correct elevations. Adding a layout lake to the existing node network after the erosion would look unnatural.

There’s a parameter called “uplift” in your erosion device. What happened is, you eroded terrain with “geological time enhancement” enabled, that exaggerates the erosion effect artificially, lowering your terrain. There’s a slider named “uplift” right below that checkbox, it raises your terrain to fit the channels properly into your terrain. This is available in the latest stable build at least. That example must be from before that feature was implemented. Project may need a complete “device version” update for new settings to appear. If you’re okay with it, PM me the project. I’ll fix it for you tomorrow.

As for the lake, I personally build my lake geometry separately. Layouts are good for blocking shapes, but a bit too crude for plugging in directly. Add a noise, and then some sparse erosion to it, and it’s ready to be combined after. Or before, if you have water in your scene. Lake needs to be plugged in “after flow restructure”, and “before create water”.

I’ll block out an example with correct usage tomorrow, it’s a bit late over here. You can already plug in water to most of your erosion devices, so that it all flows in a unifying fashion. It’s just the “order” that needs some thinking.

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I appreciate the quick reply!

I kept experimenting, but had not gotten as far as trying to check “uplift” when I came up with a nice work around. I used a spline in layout to create a rough copy of the ridgeline the flow restructure broke through to create a dam, which I added in the smallest increment in a combiner just before creating water. That gave me nice terrain-based lake(s) (I actually got three linked lakes instead of the one I envisioned, but I was pretty happy with that.

I’ll be sure to try a new scene using the “uplift” method you described to get erosion flowing into lakes and rivers the way I was going for today. I am curious about your preferred method of building lake geometry, so I look forward to your follow-up.

Thanks!

@davidroberson Here you go! This is a quick and simple example of a lake integrated into a terrain based on “create water” node.

Lake_Demo_WFab.zip (43.9 KB)

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Excellent! Thank you. I’ll look at in the morning, first thing. I’m already pushing past my bedtime!

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Hmm. Create Water is hanging at 33.3% forever. I’ve never seen water take so long to build before. Did this happen with this build for you?

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Yep, it’s natural. I cranked up “discharge scalar” to max value (16), set it back to 1 if you don’t mind smaller rivers. It adds to the build time significantly.

Good to know. I never played with that parameter, and would not have understood the rendering cost associated with higher settings.

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