earthmoonstars.py

Python Mini

from processing import *
from random import randint

# the angles for rotation
rotating_sun = 0
rotating_earth = 0
rotating_moon = 0
# the center of the canvas that everything will rotate around
center_x = 250
center_y = 250
# for drawing stars
star_count = 150
stars = []

def setup():
    size(540, 500)
    # generate random star points
    for i in range(star_count):
        x = randint(10, 530)
        y = randint(10, 490)
        width = randint(2, 8)
        height = randint(2, 8)
        color = randint(10, 100)
        stars.append({
            "x": x,
            "y": y,
            "width": width,
            "height": height,
            "color": color
        })

# this function is called once per frame, several times per second
# to draw everything
def draw():
    global rotating_sun, rotating_earth, rotating_moon
    background(0, 0, 0)
    # draw stars as the universe background
    for star in stars:
        fill(star["color"])
        ellipse(star["x"], star["y"], star["width"], star["height"])
    
    # earth orbits
    noFill()
    stroke(60, 60, 60)
    arc(center_x, center_y, 140, 140, 0, 2*PI)
    
    # change planets' rotation angle
    rotating_sun += -0.0001
    rotating_earth += -0.005
    rotating_moon += -0.06
    
    noStroke()
    # Sun
    translate(center_x, center_y)
    rotate(rotating_sun)
    fill(250, 0, 0)
    ellipse(0, 0, 30, 30)
    
    # Earth
    rotate(rotating_earth)
    fill(100, 200, 250)
    ellipse(70, 0, 13, 13)
    
    # Moon, translate its rotation center to earth
    translate(70, 0)
    rotate(rotating_moon)
    fill(250, 250, 0)
    ellipse(10, 0, 4, 4)

run()

( around 61 lines python code )

Published By:

bill nye

Published on 2017-07-14T15:05:03Z

Python Mini - an OYOclass application, own your own class today.

Result

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