Lesson 13

Review Homework

Returning a list from a function

from random import randint

def get_random_list(low, high, length):
    result = []
    for _ in range(length):
        result.append(randint(low, high))
    return result

For Each Loops

Last lesson we iterated over a list using an index variable.

some_list = [1, 4, 5, 7, 2, 56, 8]
for i in range(len(some_list)):
    element = some_list[i]
    print(element)

A simpler way to do the same thing:

for element in some_list:
    print(element)

Exercise:

Rewrite the is_in_list(any_list, x) function from last week using a for each loop.

Extension: rewrite functions from the last homework to use for each loops

Particle Effects

Exercise:

Create a Particle(Sprite) class. A particle should:

  • have a random starting direction

  • a random speed

  • deletes itself if touching edge

Create 100 particles using a for loop

Extensions:

  • bouncing off edge

  • fades out over time

  • find an image so particles look more like fire/explosion

Exercise:

Create a Button to change the color of all of the particles. Use a for each loop and window.get_all_sprites_with_tag('particle') to get the list of particles

Extensions:

  • Add multiple buttons to change the particles different colors. Can you use a single Button class?

  • Add a button to change the image or scale of the particles.

  • Create a Button to create new particles

  • Create a button to delete all particles

  • Create a button to delete particles in the order they were created.

Exercise:

Create an fireworks animation when the user clicks on the window or presses a key. The animation should have an explosion animation where particles shoot out radially from the point of explosion.