Here is a generic version of the growing mod. I've made it so other mods can use it such as my bread mod which uses it for wheat to grow. Look at the examples for papyrus and cactus on how to us it. The function add_grow_type is called with the first param as the node type you want to grow. The second param is a table of tables. Each inner table has a field for name, odds and max_height. The name field is the surface node name that the growing node must be on top of to grow. The odds field controls how fast it will grow(between 1 and 1000; lower numbers are slower growing) Figure about ((odds/100)/2)% will grow every 5 minutes. The last field, max_height, controls how many nodes high it will grow.
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