i'm trying to apply voronoi tessellation on android, but the performance is too slow. it takes about 4 seconds to generate it and after some points it takes even more.

i wonder if the problem is the device or the algorithm is too long ..... or both?!

the device is HTC desireHD (cpu  1 GHz)

i tried to simplify the code as possible as i could

1. float[] px = new float[0];
2. float[] py = new float[0];
3. float[] distance = new float[0];
4. 
   
5. void setup()
6. {
7.   size(800,480);
8.   orientation(LANDSCAPE);
9.   rectMode(CENTER);
10. }
11. 
    
12. 
    
13. void draw()
14. {
15.   //rendering points as rectangles
16.   for(int i=0;i<px.length;i++)
17.   rect(px[i],py[i],10,10);
18. }
19. 
    
20. void mousePressed()
21. {
22.   //add new point
23.   px = append(px,mouseX);
24.   py = append(py,mouseY);
25.   distance = append(distance,0);
26.   if(distance.length<2) return;
27.   
28.   for(int y=0;y<height;y++)
29.   for(int x=0;x<width;x++){
30.     //calculate the distance between the pixel and each point
31.     for(int i=0;i<px.length;i++)
32.     distance[i] = dist(x,y,px[i],py[i]);
33.     sortDistance();
34.     if(abs(distance[0]-distance[1])>5) set(x,y,color(0));
35.     else set(x,y,color(255));
36.   }
37. }
38. 
    
39. void sortDistance()
40. {
41.   for(int i=0;i<px.length-1;i++)
42.   for(int j=i;j<px.length;j++)
43.   if(distance[i]>distance[j]){
44.     float d = distance[i];
45.     distance[i] = distance[j];
46.     distance[j] = d;
47.   }
48. }

waiting for your advice ..