You may come across some specular textures in games using the Quake3 engine. Here's an example in OpenArena 0.8.1: Image:Specular textures-texture original.jpg It may look like an ordinary texture, but when you open it up in GIMP it looks nothing like ordinary. It may seem that it has just some lines, and the other parts are fully transparent, but it's not the case. If you click around with the color picker tool you will find out that the transparent parts have different colors. Image:Specular textures-gimp original.jpg So the specular textures are 100% covered textures, but how do you make them?