How to get the normal vector of the terrain in a given world position?

Unity Engine
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1

I want to get the normal vector of the terrain in a given world position.

I don’t want to do raycasts since I’ll be repeating this operation a lot of times per frame.

I know the method GetInterpolatedNormal, but since my terrain origin is not in (0,0,0), I wonder if there is some better method to get this normals.

PS: when I say world position, the y-coordinate can be ignored, since there will be only one normal for the position (x, _, z).

2

If you’re not interesting in using physics then you’re best to ask on the Scripting forum and not the physics forum.

I can move your post there if you wish.

3

To add though, even if it’s not physics, the terrain origin is irrelevant.

You can convert the world position you want into the local-space position of the Terrain by using the standard Transform.InverseTransformPoint (with the Terrain GameObject Transform).

This local-space position can then be normalized using the [size of the Terrain](http://The terrain size: Unity - Scripting API: TerrainData.size) (devide it by this). Just a standard normalization.

I’m not a terrain expert though, I’ve never actually used it.