How create plane from 4 points, and then get a normal from that plane?

PrecisionRender

I'm trying to align a Node3D based on the average positions of 4 points. This picture illustrates what I'm trying to do quite well:
Edit: C and D are reversed in that image. 😵

How would I go about getting an upward-facing normal from these 4 points? Should I create two triangles and average out their normals, or something else? Currently, I'm using this solution on Stack Overflow, but it's quite glitchy and doesn't work correctly.

xyz

PrecisionRender A plane is defined by 3 points. The fourth point may lay out of the plane defined by other 3 points. The cross product solution you linked is the best way to get the normal. So if you have points A, B and C, then the normalized cross product between vectors BA and BC will give you the plane normal, given that points are not collinear/coincident.

PrecisionRender

xyz Thanks!