Hello folks, i've been messing with PVector for now few days and gettinng almost the result i wanted but humm. not exactly... there is my class straightly from master D. Schiffman Path following sample. I'm trying to get an offset curve from vertex, i now miss the connection points for the offset. I might be dumb but cannot see how to get that.

1. // Path Following
2. // Daniel Shiffman <http://www.shiffman.net>
3. // The Nature of Code, Spring 2009
4. class Path {
5.   // A Path is an arraylist of points (PVector objects)
6.   ArrayList points;
7.   // A path has a radius, i.e how far is it ok for the boid to wander off
8.   float radius;
9.   Path() {
10.     // Arbitrary radius of 20
11.     radius = 20;
12.     points = new ArrayList();
13.   }
14.   // Add a point to the path
15.   void addPoint(float x, float y) {
16.     PVector point = new PVector(x,y);
17.     points.add(point);
18.   }
19.   // Draw the path
20.   void display() {
21.     // Draw the radius as thick lines and circles
22.     if (debug) {
23.       // Draw end points
24.       for (int i = 0; i < points.size(); i++) {
25.         PVector point = (PVector) points.get(i);
26.         //ellipse(point.x,point.y,radius,radius);
27.         //}
28.         // Draw Polygon around path
29.         for (int j = 0; j < points.size()-1; j++) {
30.           PVector start = (PVector) points.get(j);
31.           PVector end = (PVector) points.get(j+1);
32.           PVector line = PVector.sub(end,start);
33.           PVector normal = new PVector((line.y),-(line.x));
34.           normal.normalize();
35.           normal.mult(radius);
36.         
37.           PVector a = PVector.add(start, normal);
38.           PVector b = PVector.add(end, normal);
39.        
40.           if(i == points.size()-1) {
41.             start = (PVector) points.get(i);
42.             end = (PVector) points.get(0);
43.             PVector Bline = PVector.sub(end,start);
44.             PVector Bnormal = new PVector((Bline.y),-(Bline.x));
45.             Bnormal.normalize();
46.             Bnormal.mult(radius);
47.             a = PVector.add(start, Bnormal);
48.             b = PVector.add(end, Bnormal);
49.           }
50.           stroke(0);
51.           beginShape();
52.           vertex(a.x,a.y);
53.           vertex(b.x,b.y);
54.           endShape();
55.         }
56.       }
57.     }
58.     // Draw Regular Line
59.     stroke(0);
60.     noFill();
61.     beginShape();
62.     for (int i = 0; i < points.size(); i++) {
63.       PVector loc = (PVector) points.get(i);
64.       // vertex(loc.x,loc.y);
65.     }
66.     endShape();
67.   }
68. }