3D modeling & numerical simulation

### What is Draw? Example

 We will now try a simple example using Draw.

 Launch the Draw executable. Draw displays, prompts and waits for commands.Example # create two views : 2d and axonometric Draw[1]> av2d # create a 2d circle Draw[2]> circle c 0 0 1 0 5 Draw[3]> 2dfit # trim the circle and dump it Draw[4]> trim c c 0 pi/2 Draw[5]> dump c 0*********** Dump of c ************* Trimmed curve Parameters : 0 1.5707963267949 Basis curve : Circle Center :0, 0 XAxis :1, 0 YAxis :-0, 1 Radius :5 # create a 3d circle from it, and convert it into a bspline Draw[6]> to3d c c Draw[7]> fit Draw[8]> convert c c Draw[9]> dump c 0*********** Dump of c ************* BSplineCurve rational Degree 2, 3 Poles, 2 Knots Poles : 1 : 5, 0, 0 1 2 : 5, 5, 0 0.707106781186548 3 : 3.06161699786838e-16, 5, 0 1 Knots : 1 : 0 3 2 : 1.5707963267949 3 # create a surface of revolution from the spline Draw[10]> fit Draw[11]> help rev reverse : reverse name ... revsurf : revsurf name curvename x y z dx dy dz # here you must click on the curve Draw[12]> revsurf s . 5 5 0 -1 1 0 Pick an object Draw[13]> fit # rotate the view Draw[14]> u Draw[15]> erase c c # build a bspline surface and intersect it with a plane Draw[20]> convert s s Draw[21]> fit Draw[22]> plane p 5 5 5 1 1 1 1 0 0 Draw[23]> intersect c p s # pick on one of the intersection curves # you may get c_2 instead of c_1 Draw[24]> whatis . Pick an object c_1 is a 3d curve Draw[25]> clear Draw[27]> rename c_1 c Draw[28]> fit # save the curve, use any directory where you can write Draw[29]> datadir \$env(WBCONTAINER)/data/default /adv_20/BAG/data/default Draw[30]> save c curveinter c Draw[31]> exit