Global variables and functions that need refactored into classes. And an opportunity for composition.

composition_start.pde

// YOUR NAME
// Refactoring global variables and functions into appropriate classes.
// And an exploration of composition.

int carX;
int carY;
int carW;
int carH;
int engineX;
int engineY;
int engineW;
int engineH;

void setup() {
  size(500, 500);
  carX = width / 4;
  carY = height / 2;
  carW = 250;
  carH = 100;
  engineX = carX + 30;
  engineY = carY + 30;
  engineW = 50;
  engineH = 20;
}

void draw() {
  drawCar();
  drawEngine();
}

void drawCar() {
  fill(200);
  rect(carX, carY, carW, carH);
  fill(33);
  text("car", carX, carY + 10);
}

void drawEngine() {
  fill(100);
  rect(engineX, engineY, engineW, engineH);
  fill(255);
  text("engine", engineX, engineY + 10);
}