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I have simple images in black and transparent and would like to change it to white and transparent. And I want to keep the transparency (80% black and 20% transparent >> 80% white and 20% transparent, 30% black and …). I tried the fill bucket, but I wasn’t successful.
As far as I remember, in photoshop I would use layer color overlay.
How can I do this in gimp?
2
Answers
I found the solution:
Colors > Invert
does what I want. Lucky me that I want to turn black to white. Other colors would not work this way. And I still don't know how I would do it with other colors.
The general solution is to set the alpha-lock on the layer (checkerboard icon at top of the layer list) and then to bucket-fill the layer with the new color (or pattern, or gradient). The alpha-lock will make the paint only change the RGB channel but not the alpha one.