Example of fog.
MGL code:
call 'prepare2d' title 'Fog sample':rotate 50 60:light on:fog 1 box:surf a:cont a 'y'
C++ code:
void smgl_fog(mglGraph *gr)
{
mglData a; mgls_prepare2d(&a);
if(big!=3) gr->Title("Fog sample");
gr->Light(true); gr->Rotate(50,60); gr->Fog(1); gr->Box();
gr->Surf(a); gr->Cont(a,"y");
}