src/cursor/WarpingCursor.py

   1 '''
   2 Created on 29 mai 2009
   3
   4 @author: samsam
   5 '''
   6
   7 import os, sys, math
   8
   9 import pygame
  10 from pygame.sprite import Sprite
  11
  12 class WarpingCursor(Sprite):
  13     '''
  14     The class for animating the warping cursor
  15
  16         screen:
  17             the screen on which the WarpingCursor is painted
  18         images:
  19             The images constituting the animation of the cursor
  20         durations:
  21             The duration of each image in the animation
  22         centerPosition:
  23             The Position of the center of the cursor
  24         _imagePointer:
  25             A pointer to the current image
  26         _animationOffset:
  27             The time elapsed since when the current image should have been displayed
  28     '''
  29     screen = None
  30     images = None
  31     durations = None
  32     centerPosition = None
  33     _imagePointer = None
  34     _animationOffset = None
  35
  36
  37     def __init__(self, scr, images, durations, initCenterPosition,flashImage):
  38         '''
  39         Constructor
  40
  41             scr:
  42                 the screen on which the WarpingCursor is painted
  43             images:
  44                 The images constituting the animation of the cursor
  45             durations:
  46                 The duration of each image in the animation
  47             initCenterPosition:
  48                 The Position of the center of the cursor at the beginning
  49         '''
  50         self.screen = scr
  51         self.images = images
  52         self.flashImagePath = flashImage
  53         self.durations = durations
  54         self.centerPosition = initCenterPosition
  55         self.flashLength = 100
  56         self.flashing = False
  57         self.image = pygame.image.load(self.images[0]).convert_alpha()
  58         self._imagePointer = 0
  59         self._animationOffset = 0
  60         self._flashTimer = 0
  61
  62     def update(self, elapsedTime, centerPosition):
  63         '''
  64         Update the cursor's look and position
  65
  66             elapsedTime:
  67                 The time passed since the previous update
  68             centerPosition:
  69                 the new position of the creep
  70         '''
  71         self._updateImage(elapsedTime)
  72         self.centerPosition = centerPosition
  73         if self.flashing :
  74             self._flashTimer += elapsedTime
  75             if self._flashTimer > self.flashLength:
  76                 self.flashing = False
  77
  78     def _updateImage(self, elapsedTime):
  79         '''
  80         Update the cursor's image
  81
  82             elapsedTime:
  83                 The time passed since the previous update
  84         '''
  85         self._animationOffset += elapsedTime
  86
  87         if self._animationOffset > self.durations[self._imagePointer]:
  88             #New animation offset is computed first, before updating the pointer
  89             self._animationOffset -= self.durations[self._imagePointer]
  90             #point to the next image (restarts from the beginning when it reaches the end)
  91             self._imagePointer = (self._imagePointer + 1) % len(self.images)
  92
  93         if self.flashing:
  94             self.image = pygame.image.load(self.flashImagePath).convert_alpha()
  95         else :
  96             self.image = pygame.image.load(self.images[self._imagePointer]).convert_alpha()
  97
  98     def flash(self,flashLength = None):
  99         self._flashTimer = 0
 100         self.flashing = True
 101         if flashLength:
 102             self.flashlength = flashLength
 103
 104     def blit(self,surface):
 105         '''
 106         Draw the circle on surface
 107         '''
 108
 109         newPos = (self.centerPosition[0] - self.image.get_width() / 2, self.centerPosition[1] - self.image.get_height() / 2)
 110         surface.blit(self.image, newPos)
 111
 112 def createImageListFromPath(path, imageCount):
 113     '''
 114     Create a list of images for a cursor (the concatenation of the original and reversed lists of images).
 115     Images must be stored as path/imageNumber.png
 116
 117         path:
 118             The folder where the images for that cursor are stored
 119         imageCount:
 120             The number of images in the folder
 121     '''
 122
 123     tempImages = [''.join([path, '/', str(i), '.png']) for i in range(imageCount)]
 124     #tempImagesReversed = tempImages[:]
 125     #tempImagesReversed.reverse()
 126     #return(tempImages+tempImagesReversed)
 127     return(tempImages)
 128
 129 #testing
 130 if __name__ == "__main__" :
 131     window = pygame.display.set_mode((1680, 1050), pygame.FULLSCREEN)
 132     screen = pygame.display.get_surface()
 133     clock = pygame.time.Clock()
 134
 135     images = createImageListFromPath('cursorImages/black',11)
 136     durations = [50 for i in range(22)]
 137     position = (400, 300)
 138     cursor = WarpingCursor(screen, images, durations, position)
 139
 140     while True:
 141         # Limit frame speed to 50 FPS
 142         #
 143         timePassed = clock.tick(50)
 144
 145         for event in pygame.event.get():
 146             if event.type == pygame.QUIT:
 147                 sys.exit()
 148             if event.type == pygame.MOUSEMOTION:
 149                 position = event.pos
 150
 151         cursor.update(timePassed, position)
 152         cursor.blit(screen)
 153         pygame.display.flip()
 154
 155