itch.io

You can change the background with the following script call:

ThreeManager.changeTexture("filename.ext");

Run the above code every x frame in a parallel event and now you have an animated background. Something like so:

ThreeManager.changeTexture("Port_1.png");
Wait: 5 frames
ThreeManager.changeTexture("Port_2.png");
Wait: 5 frames
ThreeManager.changeTexture("Port_3.png");
Wait: 5 frames