Questions about water system (simulating LA)

[Almost_Human_Media]

Hello all. New to World Machine but an old hat in 3d landscape modelling. We are working on a very cool project that involves visualizing the water system of LA both as it is and how it could be reformed for the better. We are working in Unreal engine as well as prerendered animation via Cinema and Terragen.

Our plan for WM is to import large elevation maps of LA or pieces of it and then use the water features of WM to create vector flows that can go into Unreal Engine. So a few questions…

• can we sim water off a preexisting DEM?
• What’s the max resolution that WM can import for a DEM?
• Can we sim erosion using a landscape DEM as a starting point?

All the best and really looking forward to diving into WM. It looks like awesome fun.

Ethan Summers
Almost Human Media.

www.almosthumanmedia.com

[HYLK]

Hey, sounds like a fun project.

As far as I know, WM doesn’t support DEM files, but since it is basically a heightmap but encoded differently, would it work for you to create a heightmap out of the DEM, because those are supported by WM. So, from now on, I will answer your question as if you were using a grayscale heightmap.

• Yes, you can sim water off a preexisting heightmap, but, unless this drains water perfectly, you will get artefacts/(small) pools. You can use the Flow Restructure device to ensure water will drain perfectly, removing the artefacts, but, any preexisting lakes will be gone as well… You could do some clever masking, but that will be a lot of tweaking, and not a one button magic solution.
• From my understanding, the WM Pro version does not really have a size limit, but the amount of system RAM is the limiting factor instead. I have 32 GB of RAM and can comfortably work with 4096×4096 px heightmaps and even 8192×8192 px heightmaps are workable, as long as I don’t have that many nodes.
• You can simulate erosion based of an imported heightmap, but it will (obviously) alter your terrain.