Collision Detection and Input - Invent Your Own Computer Games with Python - page 355

18 - Collision Detection and Input
72. player.left = random.randint(0,
WINDOWWIDTH - player.width)
We will also add teleportation to our game. If the user presses the "X" key, then we will
set the position of the user's square to a random place on the window. This will give the user
the ability to teleport around the window by pushing the "X" key (though they can't control
where they will teleport: it's completely random).
Handling the MOUSEBUTTONUP Event
74. if event.type == MOUSEBUTTONUP:
75. foods.append(pygame.Rect(event.pos[0],
event.pos[1], FOODSIZE, FOODSIZE))
Mouse input is handled by events just like keyboard input is. The MOUSEBUTTONUP
event occurs when the user clicks a mouse button somewhere in our window, and releases
the mouse button. The pos attribute in the Event object is set to a tuple of two integers for
the XY coordinates. On line 75, the X-coordinate is stored in event.pos[0] and the Y-
coordinate is stored in event.pos[1] . We will create a new Rect object to represent a
new food and place it where the MOUSEBUTTONUP event occurred. By adding a new Rect
object to the foods list, a new food square will be displayed on the screen.
Moving the Bouncer Around the Screen
86. # move the player
87. if moveDown and player.bottom < WINDOWHEIGHT:
88. player.top += MOVESPEED
89. if moveUp and player.top > 0:
90. player.top -= MOVESPEED
91. if moveLeft and player.left > 0:
92. player.left -= MOVESPEED
93. if moveRight and player.right < WINDOWWIDTH:
94. player.right += MOVESPEED
We have set the movement variables ( moveDown , moveUp , moveLeft , and
moveRight ) to True or False depending on what keys the user has pressed. Now we
will actually move the player's square (which is represented by the pygame.Rect object
stored in player ) around by adjusting the XY coordinates of player . If moveDown is set
to True (and the bottom of the player's square is not below the bottom edge of the window),
then we move the player's square down by adding MOVESPEED to the player's current top
attribute. We do the same thing for the other three directions as well.