Setting layer transparency

[arcnspark]

I just loaded GMIP and am trying to see if I can use it for stacking up many pdf layers of a map.
I'm using white as the transparency color for each layer and have not found a way.
Can anyone help point me in the right direction?

[Ofnuts]

There is no such thing as a "transparency color" in Gimp (this is a concept specific to some (old) image formats). You can however replace the white by transparency:

* Add an alpha-channel if needed (Layer>Transparency>Add alpha channel)
* Colors>Color to alpha and remove the white.

[arcnspark]

(01-03-2020, 08:30 PM)Ofnuts Wrote: There is no such thing as a "transparency color" in Gimp (this is a concept specific to some (old) image formats). You can however replace the white by transparency:

* Add an alpha-channel if needed (Layer>Transparency>Add alpha channel)
* Colors>Color to alpha and remove the white.

I did see that path but thought the faded out "Add Alpha Channel" was next, and seemed blocked, and then select a color
I went directly to "Color to Alpha" as you said and got there.

Thanks a Bunch

[Ofnuts]

(01-04-2020, 04:22 PM)arcnspark Wrote: I did see that path but thought the faded out "Add Alpha Channel" was next, and seemed blocked, and then select a color
I went directly to "Color to Alpha" as you said and got there.

Thanks a Bunch

If "Add alpha channel" is grayed it means the alpha channel has already been added.