Via the bug reports 486902 - 569330, I learned that:
- in Gimp 2.6.x there was an intentional change to change the logic
concerning transparancy of upper layers depending on the
limitations/nature of the added picture.
- requesting to revisit this change - or to ask a way to re-install
the concept of Gimp 2.4.x should be done via this e-mail way
Therefore, please find my motivation below - as can also be
found in above bug reports. Note that also other express
an opinion in these bug reports.
Subject: default transparancy in upper layers disappeared
(you only get transparancy if the source image you add has this feature)
Pro (or why the change was introduced):
1. unclear - possibly a theoretical consideration
2. background layer is treated the same way as top layer (?)
1. the user must understand which types of source images have transparancy
2. the user must manually add transparancy = additional burden
3. a sudden interface change, away from the industry standard
4. a jpg image has no transparancy, but also no background color, so something
5. there is already a tool to fill to the background color
1. The learning curve is increased (newcommers are now already overwhelmed)
2. People using Photoshop, are less inclined to step over. They could use
this very recognisable deviation as motivation with "what's next?"
I see no application where an upper layer would NOT need transparancy:
It is part of the design:
Images need to be imported in the design, so the design is key, not the
of the imported image. i.e. if you import an image with 8 bit colors,
it should be converted. In the same way, the missing feature (transparancy)
must be added for jpg.
I vaguely remember that some image-formats have a background color (an 'extra'
In line with your comment #10, you claim that in that case you must preserve
that background color only for that layer, so you end up that a layer may have
In a similar way, OpenOffice.Org could decide to use white as default
pen colour, whith the motivation that pens exist in so many colours,
and the paper could be of any colour too, so that the user must first select
a pen colour.
I give basic training to beginners. I keep away from any advanced feature,
because it is already a steep learning curve. Upto now, I could get away
by not explaining anything about an alpha channel. This happens also for
other programs like i.e. MS Word: most advanced features remain unused
until the user has sufficient skills.
Intensive users use most likely Photoshop due to peer pressure, so newcommers
With this long explanation, I hope to reopen the discussion and open the
way to introduce at least an option parameter, which preferably defaults
in transparancy in all (upper) layers.
--> and not to start a discussion on every point I made <--
The option that all layers have default transparancy also looks fine:
Adding layers is a basic skill, so adding a white layer as background
image looks quite logical.
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