Hello World!

12 Days of Python – Day 7

This is Day 7 of 12 Days of Python  This is the seventh in a series of posts where we use Python and the Pygame module to draw a Christmas scene.  Each day we add something else to the scene, and we show a new aspect of Python or Pygame.  We’re also having a giveaway , where you can win a Kindle Touch!

On Day 1, we made a Pygame window and used the Pygame draw functions to draw Santa using lines circles and polygons.  On Day 2, we made Santa’s arm wave.  On Day 3, we added a calendar.  On Day 4 we added code to cross off the days on the calendar.  On Day 5, we added a background. On Day 6, we addded a Christmas tree (using recursion).

For Day 7 we’re going to add Christmas lights to the scene.  We add a new function called draw_a_light(), which draws a light of a random color.  The lights on the tree are added to the draw_a_tree() function.  It draws some arcs for the cords, and then uses the draw_a_light() function to draw the lights.  The lights in the room are drawn in lines 68 to 78.

# santa_7.py
# This is the code for Day 7 of "12 Days of Python",
# by the authors of "Hello World! Computer Programming for Kids and Other Beginners".

import pygame, sys, math, datetime, random

def draw_a_light(surface, pos):
    pygame.draw.circle(surface, pygame.color.THECOLORS[random.choice(pygame.color.THECOLORS.keys())], pos, 6)

def rotatePointAroundCenter(point, center, degrees):
    displacement = (point[0] - center[0], point[1] - center[1])
    radians = math.radians(degrees)
    newPoint = [0,0]
    newPoint[0] = displacement[0] * math.cos(radians) + displacement[1] * math.sin(radians)
    newPoint[1] = displacement[1] * math.cos(radians) - displacement[0] * math.sin(radians)
    return newPoint

def draw_a_tree(surface, leaf_size, (x,y), is_trunk=True):
    if is_trunk:
        rect = pygame.rect.Rect((x - 25, y - 30), (50,60))
        pygame.draw.rect(surface, (102,68,34), rect)
        draw_a_tree(surface, leaf_size, (x, y-30), False)
    elif leaf_size <= 2:
        return
    else:
        pygame.draw.polygon(surface, (0,200,0),((x-leaf_size/2,y),(x+leaf_size/2,y),(x,y-(2*leaf_size/3))))

        draw_a_tree(surface, 3*leaf_size/4, (x, y-leaf_size/3), False)
        if leaf_size > 30:
            light_rect=pygame.rect.Rect((0,0), (1,1))
            light_rect.width = leaf_size
            light_rect.height = 2*leaf_size/3
            light_rect.bottom = y
            light_rect.centerx = x
            pygame.draw.arc(surface, (0,0,0), light_rect, math.radians(-143), math.radians(74-110), 2)
            draw_a_light(surface, (x,y))
            draw_a_light(surface, (x - leaf_size/4, y-leaf_size/20))
            draw_a_light(surface, (x + leaf_size/4, y-leaf_size/20))

pygame.init()

pygame.display.set_caption("12 Days of Python")

screen = pygame.display.set_mode((640,480))
santa = pygame.surface.Surface((640,480)).convert_alpha()
santa.fill((0,0,0,0))
screen.fill((0,0,0))

santasArm = pygame.surface.Surface((640,480)).convert_alpha()
santasArm.fill((0,0,0,0))

background = pygame.surface.Surface((640,480))
background.fill((255,0,0))

#---BACKGROUND DRAW
pygame.draw.polygon(background, (148,123,90), ((0,480), (100,320), (540, 320), (640, 480)))
pygame.draw.polygon(background, (139,89,49), ((0,0), (100,0), (100,320), (0,480)))
pygame.draw.polygon(background, (139,89,49), ((640,0), (540,0), (540,320), (640,480)))
pygame.draw.polygon(background, (102,68,34), ((100,0) ,(540, 0), (540, 320), (100, 320)))
calendar = pygame.surface.Surface((189,150))
calendar.fill((255,255,255))

tree = pygame.surface.Surface((640,480)).convert_alpha()
tree.fill((0,0,0,0))
draw_a_tree(tree, 200, (100, 360))

#---LIGHTS DRAW
pygame.draw.arc(background, (0,0,0), pygame.rect.Rect((0,-30),(320, 60)), -math.pi, 0, 5)
pygame.draw.arc(background, (0,0,0), pygame.rect.Rect((320,-30),(320, 60)), -math.pi, 0, 5)
draw_a_light(background, (6,6))
draw_a_light(background, (80,25))
draw_a_light(background, (160,30))
draw_a_light(background, (240, 25))
draw_a_light(background, (320, 6))
draw_a_light(background, (400,25))
draw_a_light(background, (480,30))
draw_a_light(background, (560, 25))
draw_a_light(background, (634, 6))

#---CALENDAR DRAW
for i in range(0, 189, 27):
    pygame.draw.line(calendar, (0,0,0), (i,30), (i,150), 2)
for i in range(30, 151, 24):
    pygame.draw.line(calendar, (0,0,0), (0, i), (189, i), 2)

cal_head_font = pygame.font.Font(None, 26)
cal_head_surface = cal_head_font.render("DECEMBER", True, (0,0,0))
cal_head_rect = cal_head_surface.get_rect()
cal_head_rect.center = (94.5, 15)

cal_num_font = pygame.font.Font(None, 20)

for i in range(1,32):
    cal_num_surface= cal_num_font.render(str(i), True, (0,0,0))
    cal_num_rect = cal_num_surface.get_rect()
    cal_num_rect.center = (((i+3) % 7 * 27) + 13.5,((i+3) // 7 * 24) + 42)
    calendar.blit(cal_num_surface, cal_num_rect)

calendar.blit(cal_head_surface, cal_head_rect)

#---CALENDAR CROSSOUT
today = datetime.datetime.now().day

for i in range(1, today):
    pygame.draw.line(calendar, (0,0,0), (((i+3) % 7 * 27) + 27, ((i + 3) // 7 * 24) + 30),
                (((i + 3) % 7 * 27),  ((i + 3) // 7 * 24)+54), 3   )

#---L ARM DRAW
pygame.draw.polygon(santasArm,(255,0,0),((274,207),(264,197),(243,182),(226,168),
                    (215,154),(212,153),(206,158),(192,155),(183,157),
                    (182,172),(204,190),(219,208),(244,231),(261,245))) #arm n hand
pygame.draw.polygon(santasArm, (255,255,255),((243,182),(242,176),(231,167),
                    (226,168),(218,181),(204,190),(204,200),(212,208),
                    (219,208),(232,197))) #arm fur
santasRotArm = santasArm.subsurface(pygame.rect.Rect((182,153),(92, 92)))
#---R ARM DRAW
pygame.draw.polygon(santa,(255,0,0),((358,191),(405,202),(428,207),(448,212),
                    (457,220),(459,226),(457,232),(444,236),(440,243),(421,237),
                    (399,233),(389,233),(344,236))) #arm n hand
pygame.draw.polygon(santa,(255,255,255),((428,207),(418,197),(406,197),
                    (407,204),(400,215),(401,237),(421,238),(421,223))) #arm fur
#---L LEG DRAW
pygame.draw.polygon(santa,(255,0,0),((270,323),(268,345),(266,352),(305,361),
                    (309,352),(317,326),(319,312),(272,306))) #leg
pygame.draw.polygon(santa,(102,68,34),((301,370),(266,361),(247,356),(231,357),
                    (224,368),(227,380),(245,388),(272,386),(274,390),(295,391))) #boot
pygame.draw.polygon(santa,(255,255,255), ((301,370),(312,355),(303,352),(293,348),
                    (279,346),(268,342),(263,343),(266,361))) #fur
#---R LEG DRAW
pygame.draw.polygon(santa,(255,0,0),((322,326),(330,352),(331,359),(372,350),
                            (369,323),(367,311),(316,314))) #leg
pygame.draw.polygon(santa, (102,68,34),((340,369),(373,361),(396,356),(410,359),
                    (415,375),(400,387),(366,386),(365,392),(347,393),(340,386))) #boot
pygame.draw.polygon(santa,(255,255,255),((373,361),(340,369),(334,368),(326,353),
                    (345,348),(359,347),(375,343)))
#---BODY DRAW
pygame.draw.polygon(santa, (255,255,255), ((234,289),(226,299),(230,316),
                    (281,322),(304,327),(317,326),(333,322),(363,324),
                    (408,304),(410,287),(402,275),(328,208),(281,207))) #vest fur
pygame.draw.polygon(santa, (255,0,0), ((271,188),(245,231),(236,259),(234,272),
                    (235,287),(241,295),(294,302),(300,298),(304,285),
                        (298,217))) #vest 1
pygame.draw.polygon(santa, (255,0,0), ((326,235),(328,286),(330,295),(335,300),
                    (369,297),(401,277),(389,234),(357,192),(334,197))) #vest 2

pygame.draw.circle(santa,(0,0,0),(315,243),4)
pygame.draw.circle(santa,(0,0,0),(314,257),4)
pygame.draw.circle(santa,(0,0,0),(315,274),4)
pygame.draw.circle(santa,(0,0,0),(317,293),4)
#---HEAD DRAW
pygame.draw.polygon(santa, (255,255,255),((278,153),(272,188),
                    (281,211),(300,232),(315,238),(326,232),(346,215),(357,191),
                    (351,151),(278,153))) #beard
pygame.draw.polygon(santa, (255, 218, 185),((282,151),(283,166),(309,178),
                    (315,179),(321,177),(345,166),(346,152),(335,140),(310,133),
                    (289,141))) #head
pygame.draw.polygon(santa, (255,0,0),((266,139),(278,123),
                    (293,112),(315,110),(343,115),(312,85),(260,134))) #hat main
pygame.draw.polygon(santa,(255,255,255),((346,152),(335,140),(310,133),
                    (289,141),(282,151),(270,150),(261,146),(266,139),(278,123),
                    (293,112),(315,110),(343,115),(357,132))) #hat rim
pygame.draw.circle(santa,(255,255,255),(255,149),15) #hat ball
pygame.draw.circle(santa,( 50, 50, 50),(307,151),3) #eye
pygame.draw.circle(santa,( 50, 50, 50),(319,151),3) #eye
pygame.draw.polygon(santa,(255,255,255),((310,140),(301,141),(294,145),(294,149),
                    (303,145),(309,144))) #eyebrow
pygame.draw.polygon(santa,(255,255,255),((315,146),(324,146),(330,150),(331,146),
                    (326,142),(317,140))) #eyebrow
pygame.draw.polygon(santa,(255,255,255),((283,167),(287,177),(296,182),(311,176),
                    (305,169),)) #mustachelet
pygame.draw.polygon(santa,(255,255,255),((344,168),(323,166),(319,176),(336,178))) #mustachelet
pygame.draw.lines(santa, (0,0,0), False, ((307,165),(307,169),(310,173),(321,171),(322,164)),2) #nose
counter = 0
clock = pygame.time.Clock()
while 1:
    clock.tick(30)
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()
    screen.fill((0,0,0))
    #screen.blit(santasArm, (0,0))
    rotatedArm = pygame.transform.rotate(santasRotArm,math.sin(counter/5.0)*10-7)
    rotArmRect = rotatedArm.get_rect()
    rotArmPos = rotatePointAroundCenter((86,73),santasRotArm.get_rect().center,-math.sin(counter/5.0)*10+7)
    rotArmPos[0] += 190
    rotArmPos[1] += 180
    rotArmRect.center = rotArmPos
    screen.blit(background, (0,0))
    screen.blit(tree, (0,0))
    screen.blit(calendar, (400, 20))
    screen.blit(rotatedArm, rotArmRect)
    screen.blit(santa, (0,0))
    pygame.display.flip()
    counter += 1

Here’s what it looks like when you run it:

To try the code out yourself, you can cut-and-paste it from the code window above into your favorite Python editor.

On Day 8, we’ll add a computer-generated piece of art to the scene.

Warren & Carter