Let's say you'd like to add some realism or supplementary detail to your track's surface. You'll then need of course ... ? Yes, that's right, skid marks
. Here are some settings that give a nice blend for your skidmarks texture (preferably saved as DDS DXT5 with alpha channel). You can set the intensity by playing with the alpha value: 0=none to 0.x. The bigger the X, the more intense the marks will be. In the screen below: 0.8