12 Days of Python – Day 2
Welcome to Day 2 of the 12 Days of Python. This is the second in a series of posts where we will use Python and the Pygame module to draw a Christmas scene. Each day we’ll add something else to the scene, and we’ll 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.
For Day 2 we’re going to make Santa’s arm wave.
We add a second surface on which to draw the waving arm. We add a new function called rotatePointAroundCenter
to rotate surface on which the waving arm is drawn. Then, in the main loop, we use transform.rotate
to rotate that surface.
The rotatePointAroundCenter
function is used to figure out the correct position of the arm as we rotate it. We use a little bit of trigonometry with a sine function to get a smooth waving motion.
# santa_2.py # This is the code for Day 2 of "12 Days of Python", # by the authors of "Hello World! Computer Programming for Kids and Other Beginners". import pygame, sys, math 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 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)) #---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() pygame.image.save(santa,"santa.png") 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(rotatedArm, rotArmRect) screen.blit(santa, (0,0)) pygame.display.flip() counter += 1
To try the code out yourself, you can cut-and-paste it from the code window above into your favorite Python editor.
On Day 3, we’ll add a Calendar to the scene.
Warren & Carter