# Loops: Drawing with loops¶

"""

This example shows how to use functions and loops to draw a scene.
It does not assume that the programmer knows how to use classes yet.
"""

# Library imports
import random

SCREEN_WIDTH = 800
SCREEN_HEIGHT = 600

def draw_background():
"""
This function draws the background. Specifically, the sky and ground.
"""
# Draw the sky in the top two-thirds
arcade.draw_rectangle_filled(SCREEN_WIDTH / 2, SCREEN_HEIGHT * 2 / 3,
SCREEN_WIDTH - 1, SCREEN_HEIGHT * 2 / 3,

# Draw the ground in the bottom third
arcade.draw_rectangle_filled(SCREEN_WIDTH / 2, SCREEN_HEIGHT / 6,
SCREEN_WIDTH - 1, SCREEN_HEIGHT / 3,

def draw_bird(x, y):
"""
Draw a bird using a couple arcs.
"""

def draw_pine_tree(center_x, center_y):
"""
This function draws a pine tree at the specified location.

Args:
:center_x: x position of the tree center.
:center_y: y position of the tree trunk center.
"""
# Draw the trunkcenter_x

tree_bottom_y = center_y + 20

# Draw the triangle on top of the trunk
point_list = ((center_x - 40, tree_bottom_y),
(center_x, tree_bottom_y + 100),
(center_x + 40, tree_bottom_y))

def main():
"""
This is the main program.
"""

# Open the window

# Start the render process. This must be done before any drawing commands.

# Call our drawing functions.
draw_background()

# Loop to draw ten birds in random locations.
for bird_count in range(10):
# Any random x from 0 to the width of the screen
x = random.randrange(0, SCREEN_WIDTH)

# Any random y from in the top 2/3 of the screen.
# No birds on the ground.
y = random.randrange(SCREEN_HEIGHT / 3, SCREEN_HEIGHT - 20)

# Draw the bird.
draw_bird(x, y)

# Draw the top row of trees
for x in range(45, SCREEN_WIDTH, 90):
draw_pine_tree(x, SCREEN_HEIGHT / 3)

# Draw the bottom row of trees
for x in range(65, SCREEN_WIDTH, 90):
draw_pine_tree(x, (SCREEN_HEIGHT / 3) - 120)

# Finish the render.
# Nothing will be drawn without this.
# Must happen after all draw commands