add 9

9/9.1.py

@@ -0,0 +1,94 @@
+# -*- coding: utf-8 -*-
+import pygame
+from pygame.locals import *
+from sys import exit
+import math
+# from gameobjects.vector2 import Vector2
+
+class Vector2(tuple):
+    def __new__(typ, x=1.0, y=1.0):
+        # print(typ, x, y)
+        n = tuple.__new__(typ, (int(x), int(y)))
+        n.x = x
+        n.y = y
+        return n
+
+    # def __init__(self, x=1.0, y=1.0):
+    #     print(self)
+
+    def __str__(self):
+        return "(%s, %s)"%(self.x, self.y)
+
+    def __add__(self, other):
+        return self.__new__(type(self), self.x+other.x, self.y+other.y)
+
+    def __sub__(self, other):
+        return self.__new__(type(self), self.x-other.x, self.y-other.y)
+
+    def __mul__(self, other):
+        return self.__new__(type(self), self.x*other, self.y*other)
+
+    def __div__(self, other):
+        print('.=======div==========')
+        return self.__new__(type(self), self.x/other, self.y/other)
+
+    def __floordiv__(self, other):
+        print('.=======floordiv==========')
+        return self.__new__(type(self), self.x/other, self.y/other)
+
+    def __truediv__(self, other):
+        print('.=======truediv==========')
+        return self.__new__(type(self), self.x/other, self.y/other)
+
+    @staticmethod
+    def from_points(P1, P2):
+        return Vector2( P2[0] - P1[0], P2[1] - P1[1] )
+
+    def get_magnitude(self):
+        return math.sqrt( self.x**2 + self.y**2 )
+
+    def normalize(self):
+        magnitude = self.get_magnitude()
+        self.x /= magnitude
+        self.y /= magnitude
+
+background_image_filename = '../res/sushiplate.jpg'
+sprite_image_filename = '../res/fugu.png'
+
+pygame.init()
+
+screen = pygame.display.set_mode((640, 480), 0, 32)
+
+background = pygame.image.load(background_image_filename).convert()
+sprite = pygame.image.load(sprite_image_filename).convert_alpha()
+
+clock = pygame.time.Clock()
+
+position = Vector2(100.0, 100.0)
+heading = Vector2()
+# print(type(position), position)
+
+while True: 
+    for event in pygame.event.get():
+        if event.type == QUIT:
+            exit()
+
+    screen.blit(background, (0,0))
+    screen.blit(sprite, position)
+
+    time_passed = clock.tick()
+    time_passed_seconds = time_passed / 1000.0
+
+    # 参数前面加*意味着把列表或元组展开
+    destination = Vector2(*pygame.mouse.get_pos()) - Vector2(*sprite.get_size())/2
+    # 计算鱼儿当前位置到鼠标位置的向量
+    vector_to_mouse = Vector2.from_points(position, destination)
+    # 向量规格化
+    vector_to_mouse.normalize()
+
+    # 这个heading可以看做是鱼的速度，但是由于这样的运算，鱼的速度就不断改变了
+    # 在没有到达鼠标时，加速运动，超过以后则减速。因而鱼会在鼠标附近晃动。
+    heading = heading + (vector_to_mouse * .6)    
+
+    position += heading * time_passed_seconds
+    pygame.display.update()