my first post in this forum ;D

I have a simple pyramid shape in 3D, with increased strokeweight. (Taken from  http://processing.org/learning/p3d/ under 3d shapes). Now the vertices look edgy, not smooth or "straight" as I'd like them to be. What can I do? 

I've already tried "smooth()" but it doesn't seem to do anything.

Thanks in advance!

This program should run as it is, try pressing X, Y or Z key to rotate the pyramid.

2. void setup() {
3. size(800, 600, P3D); 
4. smooth();
5. }
6. 
   
7.   float x=0;
8.   float y=0;
9.   float z=0;
10. 
    
11. void draw() {
12.   background(255,0,0);
13.   strokeWeight(20);
14.   
15.   translate(width/2, height/2, 0);
16.   rotateX(x);
17.   rotateY(y);
18.   rotateZ(z);
19.   scale(100);
20. 
    
21.   beginShape();
22.   vertex(-1, -1, -1);
23.   vertex( 1, -1, -1);
24.   vertex( 0,  0,  1);
25. 
    
26.   vertex( 1, -1, -1);
27.   vertex( 1,  1, -1);
28.   vertex( 0,  0,  1);
29. 
    
30.   vertex( 1, 1, -1);
31.   vertex(-1, 1, -1);
32.   vertex( 0, 0,  1);
33. 
    
34.   vertex(-1,  1, -1);
35.   vertex(-1, -1, -1);
36.   vertex( 0,  0,  1);
37.   endShape();
38. 
    
39.   if(keyPressed && key=='x')x = x + 0.01;
40.   if(keyPressed && key=='y')y = y + 0.01;
41.   if(keyPressed && key=='z')z = z + 0.01;
42. }