TITLE: Dimensions of a rectangle containing a rotated rectangle
QUESTION [5 upvotes]: Given sides a, b, and an arbitrary rotation Θ (0 - 360 degrees) around the centerpoint of the rectangle, how would I calculate sides A and B of a containing rectangle?

REPLY [6 votes]: B = $a*sin(90-\theta)+b*sin(\theta)$
A = $b*sin(90-\theta)+a*sin(\theta)$
(Assuming the image shows minor clockwise rotation)
when $\theta=0\  $ $B=a\  $   $A=b\  $ (matching the image)