Height field in alpha channel with GIMP?

Hi!

I’m doing a parallax mapping shader.
I want to use a normal map texture, with a height field stored in the alpha channel.

(The height field image is created with the GIMP Normalmap-plug in, from my existing normal map.)

It would be great if GIMP could be used, but I can’t figure out how to copy a channel from one image into the alpha channel of another.

Any ideas?

I’m not quite following you. Are you saying you have two files on disk - one is a normal map and the other a height map?
Why can’t you just use Photoshop or paintshop pro and convert height hap to grayscale then copy that image into the alpha channel if the normal map.

I found out how to do it, see link (credz to ofnuts and mike_m).

http://gimpforums.com/thread-make-alpha-channel-from-another-image

Hmm… Can’t edit the post title?
Want to mark this as solved …