I'm working on a map that's basically one huge cliff, and I want to add texture to it by covering the whole cliff with rocks. But it will take thousands of rocks to do the job. I've tried using a forest brush, but the rocks all align to the XY plane, and I want them aligned with the local ground surface, which is anywhere from 30 to 80 degrees. Is there a way to instantiate objects, automatically aligning them to the local ground surface? I was trying to create a prefab, but I can't even get that figured out!
Try activating the "Terrain Snap" option before using the forest brush, and activate the "Keep relative rotation" checkbox. (You can see the options by right clicking the button) Although there might be an issue where they still appear to have a too horizontal rotation on steep terrain. We will look into it. A workaround that should work is to place the rocks on a horizontal surface and then selecting and moving them to the cliff while having the same options active i showed above.
Unfortunately, using that size range resulted in so many rocks, the level took forever to load. (I haven't even started adding content to the flat areas.) So I bumped up the rock size. I'm still playing around with the sink range to balance between good surface texture and having too many places to get stuck on the way down.
