lizard wrote:Works here on Mint 18 64. Never tried .res in FB. Then you could link it in the .exe to have all in one file, i suppose.
The .res extension is arbitrary but yeah, you could. But it's not such a good idea, for several reasons. The technique could be used to avoid, for example, having hundreds of files, each with a small bitmap. Of course, you can also use it to pack all the textures you need, ready to be used by OpenGL, for example.
The file format is rather dull, as the header only consist in the number of images found in the file. You can create your own custom binary file, or you custom .pak file (to have several file types in one, like Quake-era games did) if you wish.