如何在pygame中从其中心旋转精灵，旋转后仍然能够将精灵向前移动

Question

我正在尝试使用python和pygame制作游戏，我需要一个精灵能够从其中心旋转，然后以其面对的任何方向向前移动，并以相同的方式向后移动。 Sprite旨在模仿机器人及其运动。

目前，它可以很好地上下移动，但是每次单击旋转按钮时图像都会失真。

我还是python和pygame的新手，因此非常感谢您能通过一种简单的方法来解决我的问题！ 谢谢。

            import pygame
            pygame.init()
            pygame.mixer.init()         # this will allow game to have sound

            #basic settings

            grey = (227,221,220)
            black = (0,0,0)  # defining colour scheme of the game
            displayWidth = 1000
            displayLength = 600
            lead_x = displayWidth/2 - 50 # 100 is sprite length and width, so 50 is half of the sprite
            lead_y = displayLength - 100   # starting position of robot
            vel = 2            # vel = velocity: the number of pixels it will move with each movement
            rotSpeed = 15 # rotation speed
            rot = 0


            gameDisplay = pygame.display.set_mode((displayWidth,displayLength))   # game screen size

            pygame.display.set_caption('Robot Race')    # name of window

            robot = pygame.image.load('robotproto.png')


            gameExit = False
            while gameExit == False:               # defining main loop
                pygame.time.delay(15)

                for event in pygame.event.get():
                    if event.type == pygame.QUIT:
                        gameExit = True

                keys = pygame.key.get_pressed()    # variable affecting keys pressed

                # keys for up and down movement
                if keys[pygame.K_q] and keys[pygame.K_p] and lead_y > -20:
                    lead_y -= vel
                if keys[pygame.K_a] and keys[pygame.K_l] and lead_y < displayLength - 80:
                    lead_y += vel

                # keys for rotation
                rotate = pygame.transform.rotate
                if keys[pygame.K_w]:
                    robot = rotate(robot, 1)
                if keys[pygame.K_o]:
                    robot = rotate(robot, -1)


                gameDisplay.fill(grey)
                gameDisplay.blit(robot, (lead_x, lead_y))
                pygame.display.update()






            pygame.quit()
            quit()