Canvas Games: Part II - HTML5 Canvas - page 800

Finally, it sets the game state to GAME_STATE_ANIMATE_ENEMY .
GAME_STATE_ANIMATE_ENEMY
Like GAME_STATE_ANIMATE_PLAYER , this state moves and animates the tank to its new loc-
ation represented by its destinationX and destinationY values. It must do this for each
of the enemy tanks, so it uses the enemyMoveCompleteCount variable to keep count of how
many of the enemy tanks have finished their moves.
When all the enemy tanks have completed their moves, the game state is changed to the
GAME_STATE_EVALUATE_ENEMY_MOVE state.
GAME_STATE_EVALUATE_ENEMY_MOVE
Like GAME_STATE_EVALUATE_PLAYER_MOVE ,thisstatelooksatthelocationofeachtanktode-
termine which ones need to be destroyed.
If a tank occupies the same tile as the player, a wall, or another tank, the tank is “to be des-
troyed.” If the player and enemy tank occupy the same tile, the player is also “to be des-
troyed.” This “to be destroyed” state is set by placing true in the hit attribute of the enemy
tank or the player.
The game is then moved to the GAME_STATE_EVALUATE_OUTCOME state.
GAME_STATE_EVALUATE_OUTCOME
This function looks at each of the enemy tanks and the player tank to determine which have a
hit attribute set to true . If any do, that tank's dead attribute is set to true , and an explosion
is created by calling createExplode() and passing in the object instance (player or enemy
tank). In the case of the enemy, a dead enemy is also removed from the enemy array.
The GAME_STATE_ANIMATE_EXPLODE state is called next.
GAME_STATE_ANIMATE_EXPLODE
Ifthe explosions arraylengthisgreaterthan 0 ,thisfunctionloopsthrougheachinstanceand
animates it, using the explodeTiles array. Each explosion instance is removed from the ex-
plosions arrayafteritfinishesitsanimation.Whentheexplosionsarraylengthis 0 ,thegame
moves to the GAME_STATE_CHECK_FOR_GAME_OVER state.
GAME_STATE_CHECK_FOR_GAME_OVER
This state first checks whether the player is dead and then checks to see whether she has won.
The player cannot win if an enemy tank makes it to the goal on the same try as the player.