Note: You cannot use repl.it for this session. Make sure you've installed everything before you come to the session.
You can check if you have pygame installed by typing import pygame in the shell and hitting enter. If you have it setup, it will not do anything. If you don't, you will get an error.
##Starting out with Pygame
Do not name your file pygame.py! IDLE will think your file is the pygame module we are trying to use, which won't work!
We can start out by telling Pygame to open a window. This will give us a place to draw things on the screen.
import pygame
pygame.init()
screen = pygame.display.set_mode((640,480))If you tried running that code, you might notice that it doesn't work too well. Depending on your computer, it might have frozen, crashed, or opened a window and closed it really fast. This is because the program doesn't have an event loop - a way to tell the program how to keep the window open and respond to things the user does.
Here's what our code looks like with an event loop added:
import pygame
pygame.init()
screen = pygame.display.set_mode((640,480))
running = True
while running:
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
pygame.quit()##The coordinate grid
Pygame uses a coordinate system to describe where things are on the screen. (0,0) is the top-left and (640,480) is the bottom right, and anything in between is somewhere inside the window.
##Drawing Shapes
We can use Pygame to draw lines, rectangles, and circles on the screen.
Start with this code:
#setup
import pygame
pygame.init()
screen = pygame.display.set_mode((640,480))
screen.fill(pygame.color.THECOLORS['black'])
pygame.draw.line(screen,pygame.color.THECOLORS['white'],(500,450),(400,300))
pygame.draw.circle(screen,pygame.color.THECOLORS['white'],(300,300),50)
pygame.draw.rect(screen,pygame.color.THECOLORS['white'],(200,100,50,100))
pygame.display.flip()
#closing the window
running = True
while running:
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
pygame.quit()####Challenge 1 Can you change the color of all the shapes?
####Challenge 2 Can you make the circle twice as big?
####Challenge 3 Can you make the line go from the bottom left corner of the screen all the way to the top right?
####Challenge 4 Can you make another rectangle that is short and fat?
####Challenge 5 Can you make the line be on top of the other shapes?
We can also have shapes that aren't filled in:
#setup
import pygame
pygame.init()
screen = pygame.display.set_mode((640,480))
screen.fill(pygame.color.THECOLORS['black'])
pygame.draw.line(screen,pygame.color.THECOLORS['red'],(500,450),(400,300),6)
pygame.draw.circle(screen,pygame.color.THECOLORS['blue'],(300,300),50,4)
pygame.draw.rect(screen,pygame.color.THECOLORS['green'],(200,100,50,100),8)
pygame.display.flip()
#closing the window
running = True
while running:
for event in pygame.event.get():
if event.type == pygame.QUIT:
running = False
pygame.quit()####Challenge 5 Can you make another rectangle inside the existing one that has a thinner border?
##Drawing Random Shapes
We can combine random and pygame to create art! Copy the code from the starter file [random drawing.py](random drawing.py).
How can we change the art the program creates?
####Challenge 1 Can you make it draw lines with a thickness of 2?
####Challenge 2 Can you make it draw 100 lines?
####Challenge 3 Can you add to the program so it also draws circles at random locations with a random color?
####Challenge 4 Can you make those circles have a random radius between 2 and 10?
####Challenge 5 Can you add rectangles too?
####Challenge 6
Can you change the program so it adds shapes to the screen one at a time? You can use pygame.time.delay(20) to pause for a bit.
##Take Home Challenge
Draw your own picture! Go to http://colorpicker.com/ to determine the RGB values for different colors to use in your image. [Here is the finished code](finished/house drawing.py) for drawing this image:
