GIMP Version: 2.8.14
Operating System: Windows
OS Version: 8.1
GIMP Experience: Intermediate Level

---

Hi all,
For a game I do texture work for, environment reflections on the cars are governed by the Alpha Channel; White is maximum reflection, Black is no reflection.
Before being converted into the game's texture format, files are .tga format.

My normal workflow is painting the car in GIMP (Picture 1), creating a Layer at the top of the stack called 'Alpha' and painting the appropriate grey-scale shades on this layer (Picture 2).

(Doing it like this, when all the components are on separate layers, means I can more easily select areas of the same desired reflection level, rather than trying to select stuff once it's been exported to .tga)

I'll then hide the 'Alpha' layer, export to .tga and copy and paste this 'Alpha' layer into the .tga's Alpha Channel.

What I'm hoping for is a quick and easy way to turn my 'Alpha' layer into the Alpha Channel for the whole image, such that when I export to .tga I don't have to even open it.

Is there a feature (or third-party script/plug-in) to allow me to do this?

Cheers,
Doug

You could just paint a layer mask or copy a layer and paste it onto the mask. Then just apply the mask when your done (or leave it as is).

Grue expounds a very clever trick for this on Reddit.