Move in relation to surface normal (Project On Plane). Move up / down slopes DOTS [Solved]

Hello,

Was about to post a question about this, but ended up getting my answer. Figured I'de share. Apologies if this seems noobish compared to some of the advanced stuff getting posted here.

Vector3.ProjectOnPlane is:

Code (CSharp):

1. public static Vector3 ProjectOnPlane(Vector3 vector, Vector3 planeNormal)
2. {
3.      return vector - Vector3.Project(vector, planeNormal);
4. }

So you can just use the DOTS math.project to do this same logic.

This will make it so the input direction's "up" will always be in relation to the surface normal. So when moving a player controller up and down slopes, it might prevent the stair-casing jitters or bounces. Hope this helps some people!

more info here:
https://answers.unity.com/questions/1601159/i-dont-understand-vector3projectonplane.html
https://answers.unity.com/questions/1532790/what-exactly-is-the-vector3projectonplane-document.html

 

when you are sure planNormal is a valid unit vector this is faster.

Code (CSharp):

1. public static float3 ProjectOnPlane(float3 vec, float3 planNormal) => vec - math.dot(vec, planNormal);

math.project is for project one vector to other when none of them are required to be unit length. so there are some overhead calculation.

 

Oh. Unity.Physics have a plan struct.
Unity.Physics\Base\Math\Plane.cs
It will fit in most of your use case.

Edit: after a quick check, it does not have vector projection function. but it has point projection to plan funciton

 

Interesting. I'll take a look. Thanks!

 

This code does not work, and frankly I'm not sure what you were trying to do because the result is not even close to the desired. OP's solution works though.