Sometimes the question is more important than the answer.
You are right, I am sorry for the lack of clarity.
Some times information is missed in the rush of everyday life, I will take more care in the future.
Here is a comprehensive description:
I have a sprinkler array routine which involves selecting 2 points in the corners of a rectangular space.
It associates these points to a rectangular space and uses this to calculate the required number of sprinklers for said space.
It then arrays sprinkler blocks in a compliant layout around the space.
(Note the space is a merely data created by the 2 points, the only physical entities being made are the sprinklers.)
I want to make the routine more user friendly by providing a preview box around the 2 points while selecting.
The rectangle needs to have a set angle depending on angle of the room being picked.
The user will input the angle at an earlier stage to picking the points.