Re: [Gimp-user] Why does Export To require confirmation on certain files

[Steve Kinney <admin pilobilus net>]

On 12/25/2016 09:14 AM, Rick C. Hodgin wrote:
> I'm wondering what the thinking / logic was in requiring confirmation when
> exporting to a file that the original source image was loaded from?

Saving an image editing project file and exporting the visible end
result of that project as a flat format image file are very different
things.

The logic:  The GIMP is project oriented software.  If you do not save
your work in progress on an image in XCF format - with layers, paths,
masks etc. intact - you can not resume or modify your work without
starting over from scratch.  Sometimes this does not matter; other times
it matters a lot, i.e. when working on complex images for a school
project, paying customer, etc.

The usual first step when creating or editing an image with the GIMP is
to save it as an XCF file.  "Save early, save often" is a habit that
eventually pays off when a system crash or other mishap interrupts an
editing session that represents an hour's work or more.

All done?  Save as XCF one last time (Control-s), export the finished
product in the required flat pixmap format (Control+e), and close the
editing session (Control+w) or the whole program (Control-q).

If you see a warning dialog you want to ignore, do Control+d to
"discard" your unsaved project, or Control+r to "replace" a.k.a.
overwrite a flat format image file.

> I can understand if I loaded a .xcf file, or .bmp file, and then later went
> to export it to a .png file, for example, asking for confirmation before
> overwrite.  But, if I were to load a .png file, and then went to export it
> (and not "Export As..." to a new destination), but to write-out the
> original .png that was loaded, why does it ask for confirmation the first
> time?  Why not just recognize it as an editing session and save it back out
> in the same format?

If you open an XCF or BMP file and export it to PNG, there is no PNG
source file for you to overwrite and no warning dialog will appear.

But if you accidentally overwrite a source image by exporting an edited
version of it without renaming, you just lost what may have been the
only available copy of that original image forever.

Hence the confirmation dialog:  Without it, expensive mistakes could
pile up pretty fast.

> If I load a .xcf file, and then press Ctrl+S after making changes, it
> doesn't ask for confirmation.  Why does the "Export" feature require
> confirmation when writing back out to the original file it was loaded
> from?  And why after writing out those changes to the original source file,
> and going to exit, does it ask me if I want to discard my changes?  I am
> not discarding them.  I just haven't saved them in the .xcf format, but I
> have saved them in the original format.

See above:  A unique source image, overwritten by an edited version in
the same format with the same name, is a lost source image - so in most
cases, it's better not to do that.  I tend to add a .v01, .v02, etc. to
file names in cases like this.

Closing an editing session without saving an XCF file discards all the
components you may have made during that session - layers, paths, masks,
etc. - things you will have to rebuild from scratch if you come back
later to make changes, after "not" saving an XCF file.

But if you are sure this is not relevant, just do Alt+d (for "discard")
when the warning dialog pops up, to skip saving an XCF file before
closing out.

> It seems to be a conscious effort to make all non-.xcf file formats second
> or third class citizens in GIMP, and it came about when the Ctrl+S change
> was made to only work with .xcf files, and to push everything else to the
> Ctrl+E export area.

That's just the way things work in real life:  When you edit an image, a
flat pixmap file exported for print or display is a product made by
combining components created and used internally by the image editor.
In the GIMP those components can be saved as an XCF file, in Photoshop
as PSD, etc.  The image editor's own native file format is definitive,
exported generic files are derivative - "second class" relative to the
editor's native source file.

> What was the thinking / logic there?  It causes a great deal of problems
> for users.  It's also confusing because I get the message about unsaved
> changes, even after I've exported them out as .png files.  It actually
> makes me cancel the close file operation, go out and export again, and then
> close file and discard changes.
>
> It's counter-productive and it causes people issues in using GIMP for
> non-.xcf file formats.

A big crowd of people signed up at gimp-user for the sole purpose of
complaining about Save vs. Export when it was a new feature.  Some of
them obviously invested at least 10x as much time and energy arguing
about this "issue" than it would have taken them to adapt to the new
workflow.

:o)