// donnat.bvr\n \n \n// donnat\na=parametricSurface\na.setMinMax=s,0,6.3\na.setMinMax=t,0,6.6\na.setEquation=x,((2+cos(t))*cos(s))\na.setEquation=y,((2+cos(t))*sin(s))\na.setEquation=z,(sin(t))\na.setSegmentCount=20\na.color=blue\na.spawn \n\n\n\n// curve1\nb=parametricCurve\nb.setMinMax=t,-10,10\nb.setEquation=x,(2+cos(t))\nb.setEquation=y,(0)\nb.setEquation=z,(sin(t))\nb.setSegmentCount=70\nb.setThickness=0.2\nb.color=red\nb.spawn\n\n\n// curve2\nc=parametricCurve \nc.setMinMax=t,-5,5\nc.setEquation=x,(3*cos(t))\nc.setEquation=y,(3*sin(t))\nc.setEquation=z,(0)\nc.setSegmentCount=70\nc.setThickness=0.2\nc.color=gray\nc.spawn