Which side of the plane?

[daiku]

I have a plane and a group of points. How do I find out which side of the plane a particular point is on? I want all the points that are on the same side as a given point. All I can think of is to project each point onto the plane, and then get a vector between each point and it's projection, and then compare the directions of those vectors. Is there an easier way?

[TIG]

That's about it!
If the plane is from a face the face.normal is easily found.
You could also extract the plane's vector from it's 'array' ?
Project the original_point onto the plane, then offset! that cloned_point along the plane's 'normal' vector by the distance between the original_point and its projected cloned_point... and then if cloned_point == original_point the original_point is in front of the plane, otherwise it's behind the plane; you should also check separately for the original_point being exactly on the plane... and decide whether that counts or not.