Would be nice if with “size, position & rotate” could point the center with mouse by double clicking or ctrl+click or something similar as alternative to dragging the center point (seems to me such is currently not available).
Same for other things that allow moving things around for keyframe animation. Spent many hours last weeks blocking licence plates with keyframes…
It is available.
Did you notice the blue info box that appears under the player after you add a Size, Position & Rotate filter?
Click in rectangle + hold Shift to drag
Thanks. Your explanation has helped more than one person.
This seems to offer only drag, not click. Drag is sloooooooow at least on my machine, (which is still able to play 4k preview pretty ok).
Hmm I don’t understand that click part…
Do you mean you want to move the center point to a different position in the rectangle?
I want to point to a single point (doubleclick, crtl+click or something) in the preview window where the center of the clip I am moving with the filter should be moved immediately, bypassing the need to drag which is just much slower and less precise in some situations + computationally seems quite expensive also
Use case: keyframe animating a licence plate blocking black bar: just doubleclick middle of the plate when plate has moved and go 10 frames forward and repeat
Ok, I think I understand now.
So for example:
SP&R filter applied to a clip, with Keyframes activated.
A Ctrl+click (or any other shortcut) on a pixel in the preview window would automatically transfer the coordinate of that pixel in the filter’s horizontal and vertical Position boxes, and create a new keyframe.
Did I get it? 
Yes! In some situations this would make things much more convenient than dragging the object (and in other situations the dragging is superior way).
I agree that this would be a big time saver when using keyframes to track an object.
Good suggestion!
By the way… Just in case you’re not aware of it: In View > Scopes there is a Video Zoom scope.
It can give you some useful informations.
Color of a pixel, and its X and Y coordinates.
Use the mouse wheel to increase/decrease the zoom factor.
Click + hold in the zoomed area to move it.
Click on the Lock icon to keep the last click displayed.
Preview Scaling should be OFF to get the real coordinate values.
If or when dragging the center point of the SP&R area becomes super slow, maybe entering the coordinates manually will be faster?