Generates christmas trees.

christmas-tree.py

# -*- coding:UTF-8 -*-
#######################################################
#                                                     #
# This program creates chrismas trees. The initial    #
# purpose of it was to have a template to make pixel  #
# art trees for the windows of the office at NTNU.    #
#                                                     #
# Author: Håvard Slettvold aka. melwil                #
#                                                     #
# Dependencies: PyPNG                                 #
#                                                     #
#######################################################

import random
import png

GREEN = (34, 177, 76)
BROWN = (128, 64, 0)
YELLOW = (253, 216, 2)
PINK = (255, 0, 128)
RED = (237, 28, 26)

# These settings adjust the dimentions of the final tree
height = 20
width = 15
# This is to scale the pixels, if set to 1, height and width
# will be actual pixels in the image.
# If set to higher than 1, it will include a grid pattern.
degree_of_magnification = 1

def make_tree(height, width):
    if width % 2 == 0:
        width -= 1

    tree = [[(255, 255, 255) for i in xrange(width)] for i in xrange(height)]
    width_of_stem = calc_width_of_stem(width)
    height_of_stem = calc_height_of_stem(height)

    height_pointer = height-1
    width_pointer = 0
    middle = int((width / 2) + 1)

    # Input stem
    width_pointer += (width - width_of_stem) / 2
    for x in xrange(0, width_of_stem):
        for y in xrange(0, height_of_stem-1):
            tree[height_pointer - y][width_pointer + x] = BROWN

    height_pointer -= height_of_stem - 1
    width_pointer = 0

    width_of_next_branch = (width - width_of_stem) / 2

    # Branches
    while True:
        width_of_branch = width_of_next_branch
        for y in xrange(width_of_branch + int((width_of_stem / 2) + 1)):
            for x in xrange(width_of_branch + int((width_of_stem / 2) + 1)):
                tree[height_pointer - y][middle -1 + x ] = get_tree_fill()
                tree[height_pointer - y][middle -1 - x ] = get_tree_fill()
                if height_pointer - y == 0:
                    break
            width_of_branch -= 1
            if height_pointer - y == 0:
                break
        height_pointer -= (width_of_next_branch)
        width_of_next_branch -= 1
        if height_pointer - width_of_next_branch <= 0:
            break
        elif width_of_next_branch == int(width_of_stem / 2) + 1:
            break

    return tree

def get_tree_fill():
    num = random.randint(0, 90)
    if num < 10:
        return YELLOW
    if num < 20:
        return RED
    if num < 30:
        return PINK
    else:
        return GREEN

def calc_width_of_stem(width_of_tree):
    width = int(width_of_tree * 0.2)

    if width < 1:
        return 1
    else:
        if width % 2 == 0:
            return width - 1
        return width

def calc_height_of_stem(height_of_tree):
    height = int(height_of_tree * 0.2)

    if height < 1:
        return 1
    return height

def magnify(tree, degree):
    magnified = []
    for row in tree:
        magnified.append([(0, 0, 0)]*((len(row) * (degree + 1) )+1))
        for n in xrange(degree):
            current = []
            current.append((0, 0, 0))
            for pixel in row:
                current.extend([pixel]*degree)
                current.append((0, 0, 0))
            magnified.append(current)
    magnified.append([(0, 0, 0)]*((len(row) * (degree + 1) )+1))

    return magnified

tree = make_tree(height, width)
magnified = tree
magnified_width = width
magnified_height = height

if degree_of_magnification > 1:
    magnified = magnify(tree, degree_of_magnification)
    magnified_width = (width * (degree_of_magnification + 1)) + 1
    magnified_height = (height * (degree_of_magnification + 1)) + 1

flat_format = []
for row in magnified:
    current = []
    for pixel in row:
        for value in pixel:
            current.append(value)
    if width % 2 == 0:
        current.extend([255,255,255])
    flat_format.append(current)

f = open('tree.png', 'wb')
w = png.Writer(magnified_width, magnified_height)
w.write(f, flat_format)
f.close()