Hello,
I've been trying to locate a webpage that teaches you how to create normal maps for textures using simple graphics editor, but I seemed to have lost the link I had bookmarked for a while ago.
The author of the article explains the making of normal maps by using an example texture, manipulating the bitmap pixels by grayscaling, then use blue and red channels, offset a bit, and then recombine them as a normal map.
I forgot some of the steps that the author did, but I only recalled that the author just uses GIMP, I think. The author did not use any plugins or external 3rd party programs to generate the normal maps.
If anyone can help me relocate the webpage, that would be very grateful.
Thank you.