I think this is a useful addition for the cropping of images. The
way I now have to crop an image is to guess some numbers, press
Apply, check in the main LyX window whether it is correct, adjust
the numbers, check.. and so forth.
It might be useful to select the region to crop to just by using the
mouse.
Vincent
This is exactly what motivated me. And even after a lot of practice, it
still always takes a few tries to get it right.
The preview of figures in LyX is rather small by default, which is
usually good because it saves space. However, I think that would make it
a bit difficult to select the desired image region easily, because
another pixel or two makes a big difference at a small zoom factor.
So I think I would favor a pop-up window in a first implementation. This
would also be consistent with similar dialogs (such as "Browse..."). The
pop-up window could be activated by a "Crop..." button and have a couple
of controls to make a precise selection of the image region easier:
(1) "+"/"-" to zoom in and out.
(2) Two half-rectangles ("corner markers") to mark the top left and
bottom right corners? Like ┌ and ┘ (Unicode characters), or in ASCII:
___
|
|
| (image) |
|
___|
This design (unlike clicking and dragging to "draw" a rectangle) has the
advantage that an existing selection can be easily adjusted.
(a) Dragging each corner changes the size of the selected region.
(b) A finer line marks the entire selection (maybe the corners are
shown in bold red, the finer line as a hair line).
(c) With this control, panning could perhaps be implemented (in
addition to scrolling). Panning would be activated by clicking in the
center of the image (or just more than a certain number of pixels away
from the corner markers). Maybe this extra function confuses users,
though, who may be more used to using scroll bars.
An alternative to 2.a) would be to make a selection by "drawing" a
rectangle: click on the top left, and then drag the mouse to the bottom
right. That's faster but it's not obvious how to adjust the selection.
Obviously panning cannot be implemented in this version, as clicking and
dragging is already used for marking the rectangle.
Using two markers for corners would also allow keeping the default
selection; in existing documents, some users may already have defined a
bounding box. In the "drawing" approach, the existing selection is lost
each time the "Crop..." button is used.
Other opinions? For a first version, zooming is optional; panning is
definitely something that can be added at the end. So a first version
would implement 2.a) and 2.b), or the alternative to 2.a) in addition to
2.b).
--
Regards,
Cyrille Artho - http://artho.com/
We are all like soldiers,
crouching behind the fortifications we have raised.
-- Steven Erikson, "Midnight Tides"
