Houdini
Earth Rendering in Karma
I'm a space render geek
If I had a nickel for every time I was asked to do a God's eye / Earth Orbit shot zooming down to the ground, I'd have nearly a dollar. I've always had a fascination with rendering space imagery in Blender (the image below is nearly a decade old). But in recent years I've needed to create this type of stuff in both Unreal & Houdini, and so with Karma coming out of beta I built a super simple setup.

Earth LOPS
Thanks to Karma's Sky Atmosphere LOP, this was a super simple task (but not one I've seen documented anywhere in this use case). A quick note: the Sky Atmosphere LOP mirror's Unreal's Sky Atmosphere actor in nearly all settings (they're based on the same physics), so it's very easy to do the same in Unreal!

Neat things about my setup:
Everything is true-to-scale
You can simple google for a location's Lat Long coordinates, which by default are in degrees. I then enter those into a dedicated transform and you can line up that location with the world origin/ground plane
The result is that you can easily zoom in from orbit all the way down to city level, where the atmosphere still reacts to the sun appropriately
All that's left to do is some traditional landscape/height field work, add some environment meshes, and you've got a pretty seamless effect that works at nearly any scale (with some motion blur)
The textures can be swapped for different resolutions (40k is what I found at the max)
Adding cloud VDB's at the correct atmospheric height also works perfectly, and is a an easy way around issues that appear when the 2D cloud textures don't quite hold up


6/25/24