TetrArcade/arcade/examples/mountains_random_walk.py

141 lines
3.5 KiB
Python

"""
Mountains Random Walk
Idea and algorithm from:
https://hackernoon.com/a-procedural-landscape-experiment-4efe1826906f
If Python and Arcade are installed, this example can be run from the command line with:
python -m arcade.examples.mountains_random_walk
"""
# Library imports
import arcade
import random
SCREEN_WIDTH = 1200
SCREEN_HEIGHT = 700
SCREEN_TITLE = "Mountains Random Walk Example"
def create_mountain_range(height_min, height_max, color_start, color_end):
shape_list = arcade.ShapeElementList()
step_max = 1.5
step_change = 0.5
height = random.random() * height_max
slope = (random.random() * step_max * 2) - step_max
line_point_list = []
line_color_list = []
for x in range(SCREEN_WIDTH):
height += slope
slope += (random.random() * step_change * 2) - step_change
if slope > step_max:
slope = step_max
elif slope < -step_max:
slope = -step_max
if height > height_max:
height = height_max
slope *= -1
elif height < height_min:
height = height_min
slope *= -1
line_point_list.extend(((x, height), (x, 0)))
line_color_list.extend((color_start, color_end))
lines = arcade.create_lines_with_colors(line_point_list, line_color_list)
shape_list.append(lines)
return shape_list
def create_line_strip():
shape_list = arcade.ShapeElementList()
colors = (
arcade.color.RED,
arcade.color.BLACK,
arcade.color.GREEN,
arcade.color.BLACK,
arcade.color.BLUE,
arcade.color.BLACK
)
line_strip = arcade.create_lines_with_colors(
([10, 10], [500, 10],
[10, 250], [500, 250],
[10, 500], [500, 500]),
colors,
line_width=4)
shape_list.append(line_strip)
return shape_list
class MyGame(arcade.Window):
"""
Main application class.
"""
def __init__(self, width, height, title):
super().__init__(width, height, title)
self.mountains = None
arcade.set_background_color(arcade.color.WHITE)
def setup(self):
"""
This, and any function with the arcade.decorator.init decorator,
is run automatically on start-up.
"""
self.mountains = []
background = arcade.ShapeElementList()
points = (0, 0), (SCREEN_WIDTH, 0), (SCREEN_WIDTH, SCREEN_HEIGHT), (0, SCREEN_HEIGHT)
colors = (arcade.color.SKY_BLUE, arcade.color.SKY_BLUE, arcade.color.BLUE, arcade.color.BLUE)
rect = arcade.create_rectangles_filled_with_colors(points, colors)
background.append(rect)
self.mountains.append(background)
for i in range(1, 4):
color_start = (i * 10, i * 30, i * 10)
color_end = (i * 20, i * 40, i * 20)
min_y = 0 + 70 * (3 - i)
max_y = 120 + 70 * (3 - i)
mountain_range = create_mountain_range(min_y, max_y, color_start, color_end)
self.mountains.append(mountain_range)
def on_draw(self):
"""
This is called every time we need to update our screen. About 60
times per second.
Just draw things in this function, don't update where they are.
"""
# Call our drawing functions.
arcade.start_render()
for mountain_range in self.mountains:
mountain_range.draw()
def main():
""" Main method """
window = MyGame(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_TITLE)
window.setup()
arcade.run()
if __name__ == "__main__":
main()