3.7.9 Dens projection sample

Functions densz, densy, densx draw density plot on plane perpendicular to corresponding axis. One of possible application is drawing projections of 3D field. The sample code is:

int sample(mglGraph *gr)
{
  mglData c;  mgls_prepare3d(&c);
  gr->Title("Dens[XYZ] sample");  gr->Rotate(50,60);
  gr->Box();  gr->DensX(c.Sum("x"),0,-1);
  gr->DensY(c.Sum("y"),0,1);  gr->DensZ(c.Sum("z"),0,-1);
  return 0;
}