PNG-s support offset for whatever renders them in the file format. However, the
way GIMP handles the offset is less than optimal. I've included a sample image
for anybody interested to see for themselves.
So whats the issue? The file is loaded with the layer offset on canvas. That is
not productive if the person has opened the image to EDIT it. You need to
correct the offset first, then edit. Then you need to somehow restore your
offset and save remembering to check the "Save layer offset" check box. If you
forgot and closed GIMP before noticing this you end up with a broken and
ruined image and lost work. This is not good.
My suggestion is as follows:
a) do not apply the th offset to the layer.
b) save offsets from load time
c) add numeric entry boxes to the save dialog and fill them with load time
This lets the person open edit and save the particular kind of PNG-s without
any extra hassle and loss of productivity.
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