CTDP used a different way of mapping for years. It’s a development of GP4’s way to map on 3 textures. We improved this by mapping all side parts on textures 1 and 2, which are identical in mapping, but only have horizonally flipped logos. So 1 is for the right side of the car, 2 is left.
Texture 3 is the top side or shared material. Usually all cars apply to this standard, so far only Williams uses a fourth texture.
This may sound as a disadvantage at first, as we use 3 times the texture size of a single ISI-FIS-car. The thing is, that both our drivers share the same 3 textures. So not every driver has uniqe textures anymore, but instead driver 2 has the same textures, just slightly remapped. I think the following chart should explain quite well.
This way of texturing wasn’t supported by ISI at the beginning. You could use it, but the Skinning-feature to select own skins in the menu didn’t work. Thanks to ISI for adding this, although it was not easy to implement, we are glad we can use this, since it will make your day way easier.
Of course every rule has it’s exceptions. A case where this occurs is McLaren which has 3 textures per driver.