paint - OpenProcessing

mySketch
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int black=-16777216; //get() returns an int to represent color so using this to compair pixel colors lets us get colors with a red value of 0;
​
void setup(){
  //size(700,700);
  fullScreen();
  reset();
}
​
void draw(){
  for(int m=0;m<width*height;m++){
    int a = floor(random(1,width));
    int b = floor(random(1,height));
    if((get(a,b))!=black){// if pixel is not black
      int c = floor(random(0,4));// one of 4 directions
      int d = 0;// an x offset for direction
      int e = 0;// an y offset for direction
      if(c==0){// assign x and y offsets
       d=1;
       e=0;
      }else if(c==1){
       d=0;
       e=1;
      }else if(c==2){
        d=-1;
        e=0;
      }else if(c==3){
        d=0;
        e=-1;
      }
      if((get(a+d,b+e)==black)&&((a+d>0)&&(b+e>0)&&(a+d<width)&&(b+e<height))){// if the target is inside screen and is black
        int ran = 10;// makes the color change
        color clr = get(a,b);//
        int re = int(constrain(red(clr)+random(-ran,ran),0,255));
        int gr = int(constrain(green(clr)+random(-ran,ran),0,255));
        int bu = int(constrain(blue(clr)+random(-ran,ran),0,255));
        set(a+d,b+e,color(re,gr,bu));
      }
    }
  }
}
​
void keyPressed(){
  if(key==' '){
    reset();
  }
}
​
void reset(){
  background(0);
  noFill();
  stroke(255,135,0);// orange
  //stroke(random(255),random(255),random(255));
  point(width/2,height/2);
}