Arduino DIY Gamer invaders

#include <Gamer.h>
Gamer gamer;

const int laserY = 7;
int laserX = 0;
const int shipY = 0;
int shipX = 7;
int bomb1 = 0;
int bomb2 = 0;
int bomb1Y = 1;
int bomb2Y = 1;
int gunX = 0;
int gunY = 0;
boolean newShip = true;

//setup device
void setup()
{
  gamer.begin();
}
void setBombs()
{
  bomb1 = random(8);
  bomb2 = random(8);
  while (bomb2 == bomb1) bomb1 = random(8);
}


void drawShip()
{
  if (shipX > -1 && shipX < 8) gamer.display[shipX][shipY] = 1;
  if (shipX - 1 > -1 && shipX -1 < 8) gamer.display[shipX - 1][shipY] = 1;
  if (shipX - 2 > -1 && shipX -2 < 8)gamer.display[shipX - 2][shipY] = 1;
}

void drawBombs()
{
  gamer.display[bomb1][bomb1Y] = 1;
  gamer.display[bomb2][bomb2Y] = 1;
}

void drawLaser()
{
  gamer.display[laserX][laserY] = 1;
}

void readSwitches()
{
  if (gamer.isHeld(LEFT)) laserX--;
  if (laserX < 0) laserX = 0;
  if (gamer.isHeld(RIGHT)) laserX++;
  if (laserX > 7) laserX = 7;
  if (gamer.isPressed(START)) drawLaser();
}

void loop()
{
  gamer.clear();
  if (newShip)
  {
    shipX = 7;
    newShip = false;
    setBombs();
  }
  else
  {
    shipX--;
      if (shipX < 0) newShip = true;
  }

  if (shipX == bomb1)
  {
    bomb1Y++;
      if (bomb1Y < 0) bomb1Y = 7;
    bomb2Y++;
      if (bomb2Y < 0) bomb2Y = 7;
  }

  readSwitches();
  drawShip();
  drawBombs();
  drawLaser();
  gamer.updateDisplay();
  delay(300);
}