This Object is nearly the same as the aplhablend-example. The only difference between both is the texture used. Alphablend.tga uses nearly all possible alpha values from 0 up to 255;	in contrast alphamask.tga only uses the both values 0(transparent) and 255(opaque). In such cases the graphic card take over the part of z-sorting and all faces will be drawn in the correct order(from far to near).