Leonte, thanks for your help. I think you are correct. But even then, I can only make the selection smaller but not bigger! For example, if I use the mouse to make a selection rectangle of 50x100 in a single mouse action, I can then reduce the selection while maintaining the aspect ratio of 1:2. I cannot increase the selection rectangle!!
Shouldn't constrained selection resizing be constrained to the current selection rather than to some selection in the past?
I am sure editing a raw picture to a certain dimension is a very common task. For example I have a taken a facial photo at 2048 x 1920 and now need to edit it to 400x514 for a passport. I would:
a. Open the image to see the whole picture
b. Make an arbitrary rectangle selection, adjust it manually using side handles to 400x514 (it is impossible to do a rectangle with one single mouse action as the image is displayed at reduced size and sometimes there isn't enough granularity to give me 400 for example, it may jump from 398 to 401)
c. Do a constrained enlargement until it is approximately large enough to show my face
d. Move the selection to show my face in the center
e. Repeat steps c and d until I am happy that the rectangle, in the correct aspect ratio of 400:514, covers the area of the picture I want.
f. Do a resize to 400 wide.
g. I now have a image of 400x514 of the exact picture I want.
Without the ability to do constrained selection resizing (reducing and enlarging), I have to operate a calculator while keeping one finger down on the mouse!