box2d_viewer.py 文件源码

def CheckKeys(self):
        """
        Check the keys that are evaluated on every main loop iteration.
        I.e., they aren't just evaluated when first pressed down
        """

        pygame.event.pump()
        self.keys = keys = pygame.key.get_pressed()
        if keys[pygame.K_LEFT]:
            self.viewCenter -= (0.5, 0)
        elif keys[pygame.K_RIGHT]:
            self.viewCenter += (0.5, 0)

        if keys[pygame.K_UP]:
            self.viewCenter += (0, 0.5)
        elif keys[pygame.K_DOWN]:
            self.viewCenter -= (0, 0.5)

        if keys[pygame.K_HOME]:
            self.viewZoom = 1.0
            self.viewCenter = (0.0, 20.0)