text: /**
   * CG Space Invaders
   * CG45179 16'17
   *
   * @author: Rui Ventura ( ist181045 )
   * @author: Diogo Freitas ( ist181586 )
   * @author: Sara Azinhal ( ist181700 )
   */
  
  /**
   * According to http://keycode.info
   */
  
  export const KEY_TAB = 9;
  
  export const KEY_SHIFT = 16;
  export const KEY_CTRL  = 17;
  export const KEY_ALT   = 18;
  export const KEY_CAPS  = 20;
  
  export const KEY_ESC = 27;
  
  export const KEY_SPACEBAR = 32;
  
  export const KEY_LEFT  = 37;
  export const KEY_UP    = 38;
  export const KEY_RIGHT = 39;
  export const KEY_DOWN  = 40;
  
  export const KEY_0 = 48;
  export const KEY_1 = 49;
  export const KEY_2 = 50;
  export const KEY_3 = 51;
  export const KEY_4 = 52;
  export const KEY_5 = 53;
  export const KEY_6 = 54;
  export const KEY_7 = 55;
  export const KEY_8 = 56;
  export const KEY_9 = 57;
  
  export const KEY_A = 65;
  export const KEY_B = 66;
  export const KEY_C = 67;
  export const KEY_D = 68;
  export const KEY_E = 69;
  export const KEY_F = 70;
  export const KEY_G = 71;
  export const KEY_H = 72;
  export const KEY_I = 73;
  export const KEY_J = 74;
  export const KEY_K = 75;
  export const KEY_L = 76;
  export const KEY_M = 77;
  export const KEY_N = 78;
  export const KEY_O = 79;
  export const KEY_P = 80;
  export const KEY_Q = 81;
  export const KEY_R = 82;
  export const KEY_S = 83;
  export const KEY_T = 84;
  export const KEY_U = 85;
  export const KEY_V = 86;
  export const KEY_W = 87;
  export const KEY_X = 88;
  export const KEY_Y = 89;
  export const KEY_Z = 90;
  
  export const KEY_F1  = 112;
  export const KEY_F2  = 113;
  export const KEY_F3  = 114;
  export const KEY_F4  = 115;
  export const KEY_F5  = 116;
  export const KEY_F6  = 117;
  export const KEY_F7  = 118;
  export const KEY_F8  = 119;
  export const KEY_F9  = 120;
  export const KEY_F10 = 121;
  export const KEY_F11 = 122;
  export const KEY_F12 = 123;
  