Ball Movement in PyGame
When building a game using PyGame, you often encounter the problem of how to move objects on the screen. While building a table tennis game, the author tried to move the ball but ran into some problems. When the move_right method is called, the ball does not move to the right, but extends to the right.
The root of the problem
The root of this problem lies in the drawing mechanism of PyGame. In each frame, PyGame draws all objects onto the display surface. Therefore, if the previous frame is not cleared, the newly drawn object will be superimposed on the old object, causing a trailing effect.
Workaround
To solve this problem, the display surface needs to be cleared at the beginning of each frame. The code can be modified like this:
while True: # [...] screen.fill(0) # <--- 清除顯示表面 main.draw_elements() main.move_ball() main.ball.x_pos += main.ball.speed pygame.display.flip() # [...]
By clearing the display surface at the beginning of each frame, you can remove the trailing effect and allow the ball to move correctly instead of leaving a trail.
The above is the detailed content of Why Does My PyGame Ball Stretch Instead of Move?. For more information, please follow other related articles on the PHP Chinese website!

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