So I was rushing into it earlier, just so I could finish it.
But after some thoughts, I could make it better, I mean, a lot better. The idea is just like day 23, the turtle crossing game, except for just a bit complex. So, I spent some time on finding the good background, the good images to use, the good sound effect etc. But once that’s done, I can almost copy what I did in day 23. So I have a play.py to control the logic, a Ship class to control the ship and its movement, a BulletManager class to control the bullets, an InvaderManager class to control the invaders and the movements, and a scoreboard class to keep the score. All that’s left is the images and sound effect. Now I learned the images can be done by “turtle.register” first, then it can be done like a “shape”, and then the winsound can be used for sound effect.
After all, this is not as hard as I thought it would be, and the finish work is better than I like. The next improvement can be a “random shown invader”, but that’s for next time.