The game works now! It’s actually quite playable. The fact it’s tetris isn’t really important, more that it helps think about playing a game from a plant’s POV – the blocks could be nutrients provided by the roots, which you fit together to grow your plant. The problem is that you can’t see yourself, (the central player plant is still there, just clipped from the camera). I need to look at more of a third plant perspective next.
The code is here.