Game Development Reference
In-Depth Information
list. The first item will be stored in the
x
variable and the second will be stored in the
y
variable. We then put these two variables into another two-item list, which we store in the
previousMoves
list with the
append()
method. This means
previousMoves
is a
list of XY coordinates of each move the player makes in this game.
The
x
and
y
variables, along with
theBoard
and
theChests
(which represent the
current state of the game board) are all sent to the
makeMove()
function. As we have
already seen, this function will make the necessary modifications to the game board. If
makeMove()
returns the value
False
, then there was a problem with the
x
and
y
values
we passed it. The
continue
statement will send the execution back to the start of the
while
loop that began on line 179 to ask the player for XY coordinates again.
Finding a Sunken Treasure Chest
195. else:
196. if moveResult == 'You have found a sunken
treasure chest!':
197. # update all the sonar devices currently
on the map.
198. for x, y in previousMoves:
199. makeMove(theBoard, theChests, x, y)
200. drawBoard(theBoard)
201. print(moveResult)
If
makeMove()
did not return the value
False
, it would have returned a string that
tells us what were the results of that move. If this string was
'You have found a
sunken treasure chest!'
, then that means we should update all the sonar devices
on the board so they detect the second closest treasure chest on the board. We have the XY
coordinates of all the sonar devices currently on the board stored in
previousMoves
. So
we can just pass all of these XY coordinates to the
makeMove()
function again to have it
redraw the values on the board.
We don't have to worry about this call to
makeMove()
having errors, because we
already know all the XY coordinates in
previousMoves
are valid. We also know that
this call to
makeMove()
won't find any new treasure chests, because they would have
already been removed from the board when that move was first made.
The
for
loop on line 198 also uses the same multiple assignment trick for
x
and
y
because the items in
previousMoves
list are themselves two-item lists. Because we
don't print anything here, the player doesn't realize we are redoing all of the previous
moves. It just appears that the board has been entirely updated.
Checking if the Player has Won
203. if len(theChests) == 0:
