Anomalous preview for semi-transparency
GIMP version:
Operating System: Linux kubuntu 16.04
Package: Gimp 2.10.8 flatpak
Description of the bug
8 bit preview Levels or Brightness-Contrast
Reproduction
Is the bug reproducible? always
Reproduction steps:
- A working 8 bit canvas
- A transparent layer with semi-transparent graphic. Typically a copy-paste that had C2A applied.
- Apply a default Levels or Brightness-Contrast to make the graphic darker.
- Ok it and the layer is unaltered.
…
Expected result: Darker graphic
Actual result: No change.
Alter the precision to 16 or 32 bit FP and the change is applied.
Going to be a rare occurrence, but this came up on a Gimp forum. Just the sort of problem that affects beginners and what-you-see is not what-you-get. Of course the solution is use the Alpha Channel in Levels but nothing is available in Brightness-Contrast.
In Gimp 2.8 the effect is not shown in the first place and makes the user look for a solution.