2D random walk using Processing

//To show 2D random [some limitation in the code] walk using Processing // Copyright by http://scriptdemo.blogspot.com myParticles[] myP; int numP=2; boolean IsLine=false; void setup() {   size(400,400);   background(0);   myP=new myParticles[numP];   for (int i=0; i<numP; i++)   {     myP[i]= new myParticles();     myP[i].x=random(100,300);     myP[i].y=random(100,300);   }   frameRate(50); } void draw() {   for(int i=0; i<numP; i++)   {     myP[i].move();     if (ceil(myP[i].x)== width | ceil(myP[i].y) == height)     {       noLoop();     }   } } void mouseClicked() {   background(0); } void mouseReleased() {   for(int i=0; i<numP; i++)   {     myP[i].setxy(mouseX,mouseY);   }   IsLine=!IsLine;   loop(); } class myParticles {   public float x0;   public float y0;   public float x;   public float y;   public void myParticles()   {   }   public void setxy(float tmpx, float tmpy)   {     x=tmpx;     y=tmpy;   }   public void move()   {     for ( int i=20; i<=60; i=i+10 )     {       float tmpx, tmpy;       float myangle;       float dx=5;       float dy=5;       x0=x;       y0=y;       myangle=(i+floor(random(-5,5)))*PI/180.0;       tmpx=dx*random(-1,1);       tmpy=dy*random(-1,1);       x=x+tmpx*cos(myangle)-tmpy*sin(myangle);       y=y+tmpy*cos(myangle)+tmpx*sin(myangle);       if ( x<0 ) { x=0.0; }       if ( x>width ) { x=width; }       if ( y<0 ) {y=0.0;}       if ( y>height ) { y=height; }       int rr=floor(random(255));       int rg=floor(random(255));       int rb=floor(random(255));       stroke(rr,rr,rb);       if (IsLine)         {           line(x0,y0,x,y);         }        else       {         point(x,y);       }     }   } }