Awarding the Player Extra Ships
We want to award the player extra ships at regular intervals based on her score. We do this by setting an amount of points that the game player must achieve to earn a new ship—this also helps us keep a count of the number of ships earned:
function
checkForExtraShip
()
{
if
(
Math
.
floor
(
score
/
extraShipAtEach
)
>
extraShipsEarned
)
{
playerShips
++
extraShipsEarned
++
;
}
}
We call this function on each frame tick. The player earns an
extra ship if the score/extraShipAtEach
variable (with the
decimals stripped off) is greater than the number of ships earned. In
our game, we have set the extraShipAtEach
value to 10000
. When the game starts, extraShipsEarned
is 0
. When the player’s score is 10000
or more, score/extraShipAtEach
will equal 1
, which is greater than the extraShipsEarned
value of 0
. An extra ship is given to the player, and
the extraShipsEarned
value is
increased by 1
.
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