4.1 Processing Basic 3D

///camera varibles
int oldx = mouseX;
int oldy = mouseY;
float rotx = 0;
float roty = 0;
float zcam = 0;

void setup() {
  size(1000, 500, P3D);
}

void draw(){
  background(0);
  cam();
  fill(255);
  rectMode(CENTER);
  rect(0,0,200,200);
}

void cam() {
  int newx = mouseX;
  int newy = mouseY;
  translate(width/2, height/2,zcam);
  rotateY(rotx);
  rotateX(roty);
  //rotateZ(PI);
  if ((mousePressed == true)) {
    rotx = rotx + (oldx-newx)/50.0;
    roty = roty + (oldy-newy)/50.0;
  }
  oldx = newx;
  oldy = newy;
}

void mouseWheel(MouseEvent event) {
  float e = event.getCount();
  zcam = zcam - e*5;
}