PVector p1;
PVector p2;
PVector V1 = new PVector(0,0);
PVector V2 = new PVector(0,0);
int S = 20;

void setup(){
   size(800,800,P3D);//<===This is using the 3D renderer

   //noStroke(); //the sphere looks awful with stroke turned on.
   p1 = new PVector(width/2, height/2, 0);
   p2 = new PVector(width/2, height/2, 0);
   V1.add(PVector.random2D());
   V2.add(PVector.random2D());
}
void mouseWheel(MouseEvent e) {
  int size = 2;
  S += (e.getCount()* size);
  if (S < 0) {
     S = 5;
  }
}
void Limit() {
  if (p1.x > 800-S) {
     V1.mult(-1);
  } else if (p1.x < 0+S) {
    V1.mult(-1);
  } else if (p1.y < 0+S) {
    V1.mult(-1);
  } else if (p1.y > 800-S) {
    V1.mult(-1);
  } else if (p2.x > 800-S) {
    V2.mult(-1);
  } else if (p2.x < 0+S) {
    V2.mult(-1);
  } else if (p2.y < 0+S) {
    V2.mult(-1);
  } else if (p2.y > 800-S) {
    V2.mult(-1);
  }
}
void draw(){
   background(100);
   mouseWheel();
   Limit();
   /*
   p1.x = mouseX;
   p2.x = mouseX;
   p1.y = mouseY;
   p2.y = mouseY;
   */
   p1.z = S;
   p2.z = S;
   //the sphere is drawn at the origin so we need to move the origin to the location we want.

   p1.add(V1);
   p2.add(V2);
   println(p1.z, p2.z);

   pushMatrix();
   translate(p1.x, p1.y, p1.z);//move the origin to where we hant the sphere
   fill(78+ 177*sin((float)frameCount*PI/frameRate) ,128 + 127*sin((float)frameCount*PI/frameRate), 128 + 127*sin((float)frameCount*PI/30),28 + 227*sin((float)frameCount*PI/frameRate));
   sphere(50);
   popMatrix();

   pushMatrix();
   translate(p2.x, p2.y, p2.z);
   fill(78+ 177*sin((float)frameCount*PI/frameRate) ,128 + 127*sin((float)frameCount*PI/frameRate), 128 + 127*sin((float)frameCount*PI/30),28 + 227*sin((float)frameCount*PI/frameRate));
   sphere(50);
   popMatrix();



}