Rotate & Enlarge Image to Fit Result //SOS//

[huangwj]

Hi,

    I used Image=>Transform=>Rotate commands to rotate an active image for an angle A. In order to avoid clipping, I also check Enlarge to Fit Result meanwhile. The size of the former image is M * N pixel, and K*L pixel for the rotated and enlarged image.  If there is a point in the former image, the coordinate of which in the former image is (X, Y), and the coordinate of the point in the rotated and enlarged image is (X2, Y2), could you please tell me the relationship between (X, Y) and (X2, Y2)?
I do not know at all about the algorithm of Rotate & Enlarge Image to Fit Result. Is there anyone who know about the algorithm?

Huang
Tohoku University