1. CADjs Polygons and Polyarcs

2. Review Question Base: (50,50,2) Cylinder: r =5, h = 30 Hole: r = 2
Use one for-loop!
Step 1
Step 2
Step 3
Step 4

3. Review Question - Solution
base = cube(50,50,2);
cyl1 = cylinder(5,30).rotateX(90).translateZ(15);
cyl2 = cylinder(2,40).rotateX(90).translateZ(20);
tube = cyl1.difference(cyl2).translate(20,20,0);
for (i = 0; i < 4;i++) {
tube.rotateZ(90*i);
base = base.union(tube); }
base.display();

4. Wedge
How to create?
Subtract one cube from another!

5. Wedge s=polygon([ [0,0],[1,0],[0,1] ]); s.display(); (1,0) (0,0) (1,0)
g = extrudeShape(s,0.25);//thickness
g.display();

6. Star
(0,50)
(10,10)
s = polygon([[0,50],[10,10],[50,10],[15,-10],[30,-50],[0,-20],[-30,-50],[-15,-10],[-50,10],[-10,10]]);
s.display();
(50,10)

7. Star
s = polygon([[0,50],[10,10],[50,10],[15,-10],[30,-50],[0,-20],[-30,-50],[-15,-10],[-50,10],[-10,10]]);
s.display();
g = extrudeShape(s,10);
g.display();

8. Hollow Wedge s=polygon([ [0,0],[1,0],[0,1] ]);
h = polygon([ [0.1,0.1],[0.8,0.1], [0.1,0.8]]);
s.holes.push(h);
s.display();
g = extrudeShape(s,0.2);
g.display();

9. Star with Hole

10. Star with Hole
s = polygon([[0,50],[10,10],[50,10],[15,-10],[30,-50],[0,-20],[-30,-50],[-15,-10],[-50,10],[-10,10]]);
star = extrudeShape(s,10);
hole = cylinder(5,30).rotateX(90);
star = star.difference(hole);
star.display();

11. Try …
100
R = 5 20 10

12. Engineering Drawings

13. More Examples
Method 1:
Block + Cylinder
Method 2:
Sketch and Extrude

14. 2D Shape with Arcs (0,1) (1,1) (1,0.5) Anti-clockwise (0,0) (1,0)
s = start2DGeom(0,0);
s.addLine(1,0);
s.addArc(1,1,1,0.5,false); //xEnd,yEnd,xCenter,yCenter,Clockwise
s.addLine(0,1);
s.display();//display 2D shape

15. 2D Shape with Arcs s = start2DGeom(0,0);
s.addLine(1,0).addLine(1,0.4).addLine(0.5,0.4);
s.addArc(0.4,0.5,0.5,0.5,true); //xEnd,yEnd,xCenter,yCenter,Clockwise
s.addLine(0.4,1).addLine(0,1).addLine(0,0);
s.display();//display 2D shape
(1,0.4)
(0,0)
(1,0)
(0.4,0.5)
(0.5,0.5)
(0.5,0.4)
Clockwise

16. Example

17. Method 1 g= cube(60,20,38).translateZ(21);
g2 = cylinder(30,20,100);
g3 = cylinder(15,50,39); g = g.difference(g1).union(g2).difference(g3); g.display();

18. Method 2
arc = [38,60,38,30,false];
s=polyarc([[0,0],[38,0], arc,[0,60],[0,45],[10,45],[10,15],[0,15] ] );
g = extrudeShape(s,20);
cyl = cylinder(15,25).rotateX(90).translate(38,30,10);
g = g.difference(cyl);
g.display();

19. Method 3
arc = [38,60,38,30,false];
s = polyarc([[0,0],[38,0], arc,[0,60],[0,45],[10,45],[10,15],[0,15] ] );
c = circle(38,30,15);
s.holes.push(c);
g = extrudeShape(s,20);
g.display();