我有一项任务要求我执行以下操作：
使用 Google 的高级图片搜索功能可以找到尺寸合理、可免费重复使用且包含透明度的球图片。修改示例代码，使您的球在屏幕底部来回滑动。球从左侧移动到右侧需要 2 秒。改进问题 5 的动画，使球准确地旋转，就好像它来回滚动一样。修改问题 6 的动画，使球逆时针绕屏幕边缘移动
我在最后一部分。尝试修改问题 6 的动画以执行此操作：(1:24) http://www.youtube.com/watch?v=CEiLc_UFNLI&feature=c4-overview&list=UUpbgjjXBL3hdTKDZ0gZvdWg
我很难过。我似乎无法理解如何让球慢慢地从一个点移动到另一个点。球是一个图像。这是我到目前为止所拥有的，但它不起作用。
"""Some simple skeleton code for a pygame game/animation
This skeleton sets up a basic 800x600 window, an event loop, and a
redraw timer to redraw at 30 frames per second.
"""
from __future__ import division
import math
import sys
import pygame
class MyGame(object):
def __init__(self):
"""Initialize a new game"""
pygame.mixer.init()
pygame.mixer.pre_init(44100, -16, 2, 2048)
pygame.init()
# set up a 640 x 480 window
self.width = 800
self.height = 600
self.img = pygame.image.load('ball.png')
self.screen = pygame.display.set_mode((self.width, self.height))
self.x = 0
self.y = 0
self.angle = 0
self.rotate_right=True
self.first = True
#0: Move bottomleft to bottomright 1: Move from bottomright to topright 2:Move from topright to topleft 3:Move from topleft to bottomleft
self.mode = 0
# use a black background
self.bg_color = 0, 0, 0
# Setup a timer to refresh the display FPS times per second
self.FPS = 30
self.REFRESH = pygame.USEREVENT+1
pygame.time.set_timer(self.REFRESH, 1000//self.FPS)
def get_mode(self):
rect = self.img.get_rect()
if self.first == True:
self.first = False
return
if (self.x, self.y) == (0, self.height - rect.height):
#Our starting point, bottom left
self.mode = 0
elif (self.x, self.y) == (self.width-rect.width, self.height-rect.height):
#Bottom right
self.mode = 1
elif (self.x, self.y) == (self.width-rect.width, 0):
#Top Right
self.mode = 2
elif (self.x, self.y) == (0,0):
#Top Left
self.mode = 3
def get_target(self):
rect = self.img.get_rect()
if self.mode == 0:
targetPosition = (0, self.height - rect.height)
elif self.mode == 1:
targetPosition = (self.width-rect.width, self.height-rect.height)
elif self.mode == 2:
targetPosition = (self.width-rect.width, 0)
elif self.mode == 3:
targetPosition = (0,0)
return targetPosition
def get_angle(self):
if self.angle == 360:
self.rotate_right = False
elif self.angle == 0:
self.rotate_right = True
if self.rotate_right == True:
self.angle+=12
else:
self.angle-=12
def run(self):
"""Loop forever processing events"""
running = True
while running:
event = pygame.event.wait()
# player is asking to quit
if event.type == pygame.QUIT:
running = False
# time to draw a new frame
elif event.type == self.REFRESH:
self.draw()
else:
pass # an event type we don't handle
def draw(self):
"""Update the display"""
# everything we draw now is to a buffer that is not displayed
self.screen.fill(self.bg_color)
#Draw img
rect = self.img.get_rect()
#Note: this can be made dynamic, but right now since this is typically a poor structure, we will use static values.
#80 is the padding, so it hits right before.
#0,0 : top left
#self.width-rect.width, 0 : top right
#0, self.height-rect.height : bottom left
#self.width-rect.width, self.height-rect.height : bottom right
targetPosition = ()
#img = pygame.transform.rotate(self.img, self.angle)
img = self.img
self.get_angle()
self.get_mode()
targetPosition = self.get_target()
print targetPosition
print self.x, self.y
if self.x < targetPosition[0]:
self.x+= targetPosition[0]-self.x//self.FPS
elif self.x > targetPosition[0]:
self.x-= targetPosition[0]+self.x//self.FPS
if self.y < targetPosition[1]:
print "s"
self.y+= targetPosition[1]-self.y//self.FPS
elif self.y > targetPosition[1]:
self.y-= targetPosition[1]+self.y//self.FPS
rect = rect.move(self.x, self.y)
self.screen.blit(img, rect)
# flip buffers so that everything we have drawn gets displayed
pygame.display.flip()
MyGame().run()
pygame.quit()
sys.exit()