I used masking for breaking an image into the below pattern. Now that it's broken into different pieces I need to make a rectangle of each piece. I need to drag the broken pieces and adjust to the correct position so I can reconstruct the image. To drag and put at the right position I need to make the pieces rectangles but I am not getting the idea of how to make rectangles out of these irregular shapes. How can I make rectangles for manipulating these pieces?

This is a follow up to my previous question.