There's like money now Update
This was about 85% another backend update, static declaration of where my actual plot squares sit (since I'm not using a grid or tilemap for this demo) are now sent to a helper method that calculates where everything goes based on some 'constants', and anything I can define before a _ready or _init function are defined at the top of my scripts. I'm not sure if it's cleaner but it will at least be more modular.
But also... money was added to the demo... so now there's a point to growing plants, and you start with a singular dollar.
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There's only one seed you can buy to start, it grows quick and sells for 2 dollars. The custom slower plant I made in Slow Update is 3 dollars but sells for 5 after growing slowly. There's not a shop yet, it's just automatically credited to your Inventory, which currently only holds money.
What I'd like to do to wrap up the demo is have the player choose what seeds go where from their inventory, and have the shop have seeds available, because right now the plots are set to a specific type of seed. Additionally, the graphics for the plot may need to be separated from the logic of the growth of the plant, but that may be for an actual game.
I at least feel like this is a reasonable demo for a farm, with the last one or two bits added in. Soon I will have a very bland farming mechanic, and it's going to be very basic, but it'll be created.