Determine position in front of 3D plane (cartesian math)

Question

I have a planar element in 3D space that I've rotated on the x, y and z axis. I'm positioning a 3D camera in front of the planar but I need to find a way to calculate the x, y, z of the camera.

I'm trying to figure out how to place the camera at x distance from the planes face. There's obviously a bit of trig involved but for the life of me can't figure it out. Gah.

Dave

Answer 1

If you have a plane then you also have its normal vector N and some point on it P.
If you calculate P'=P+x*N you'll get the point P' which is x units infront of point P in the direction of the normal.