I have searched a lot about this, and couldn't find anything apart a few lines
in an old summer of code page, and in this old webpage :
unfortunately this patch only applies to 2.3
this is why I allow myself to post here as a feature wish, even though I am
absolutely not a coder.
I am using GIMP every single day for my 3D texturing work, and i have to blend
together parts of photographies in an interactive way.
Parts need to be lined accurately so that you don't create blur in the
( someone told me Hugin does it perfectly, but at a first glance, it seems to
involve complex settings and a lot of click work before it computes a
solution, when you just need to move things on the fly and see how it goes .
Hugin seems to be more suitable for assembling large images together than a
lot of little parts )
As GIMP is now, you need to move/scale/rotate/shear/perspective a selection or
a layer, apply transformation, check if it lines good, undo, transform again,
check, etc, because the preview always turn to totally opaque , whatever the
layer opacity is.
Having a little slider to set the preview mode/transparency would be a real
enhancement for this kind of workflow.
Another clean solution would be that the preview simply follows the active
layer mode/opacity .
I have read about Iwarp as a tool, that combined with a transparent transform
preview would turn GIMP into a fantastic texturing tool.
I have no clue how difficult it can be to code this, but I hope the developers
of GIMP can find an interest in this.
With all my thanks for all the work done,
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