User manual

This line tells the user, what to do. Each time you press any key on the keyboard rolls the dice.

always writes into the Python Shell window, not in the new graphical window.

while mainloop: Now the main loop of the game starts. In many games an infinite loop is used which is

repeated over and over again and constantly queries any user activity. Somewhere in the loop an abort

statement must be defined, which ensures that the game can exit.

We use the variable

mainloop here which only adopts the two Boolean values True und False (true and

false, on and off). It starts with

True and is queried with each loop run. If it adopts the value False during

the loop, the loop is aborted before the next run.

for event in pygame.event.get(): This line reads the most recent user activity and saves it as event. The

game has only two types of game-relevant user activities: The user presses a key and thus rolls the dice, or

the user wants to end the game.

if event.type == QUIT or (event.type == KEYUP

and event.key == K_ESCAPE):

mainloop = False

There are two ways to exit the game: Either you can click the X icon in the upper right corner on the window

or you can press the

[Esc] key. By clicking on the x icon the operation system delivers the event.type ==

QUIT

. If you press and release a key that is the event.type == KEYUP. In this case, the pressed key is also

stored in

event.key.

The described

if statement verifies whether the user wants to close the window, or (or) has pressed and

released a key and (

and) whether this is the key with the internally used name K_ESCAPE. If this is the case,

the variable

mainloop is set to False that will exit the main loop of the game prior the next run.

if event.type == KEYDOWN: The second type of user activity that reoccurs more than once again during the

game, is the user presses a key. It is not important which key, yet with the exception of the key

[Esc]. As

soon as a key is pressed

KEYDOWN), an important part of the program is actuated, which generates and

displays the dice result.

FIELD.fill(BLUE) First the surface-object, the actually window of the application named FIELD is filled

with the color defined as

BLUE to paint over the dice result scored.

NUMBER = random.randrange (1, 7)

The random function random now generates a random number between 1 and 6 and saves it in the variable

NUMBER.

print ZAHL This line writes the score of the dice roll into the Python Shell window. You may also omit this

line if you rather want to do without the text-based output.

if NUMBER == 1:

pygame.draw.circle(FIELD, WHITE, P1, 40)