Hey Ice,
As I understand it(and my knowledge on the landscaping tool is limited), but it essentially just places static meshes around the world in the defined area of the brush. So one possibility is creating custom object, that have different stages and have animation montages that tie the stages together.
So for Example you have a grass class. Well you could have 5 different basic meshes; one for 0%, 25%, 50%, 75%, and 100%.
Then basically have the grass determine if it needs to grow to the next stage, and use a simple animation to transfer from one stage to another.
So lets say you cut your grass, so it would be at 0%.
Create a function that basically is bool canGrow(), and pass in any parameters; like how many times its been run over or passed by. How much time has passed in the game world, or anything that you would want to influence it.
Then let that be called either on the tick or every x seconds.
Once you have that running, and assuming it calls the function and we can grow; check which stage it should be at. So, lets say we are at ~24% and about to hit the 25%. Well we keep playing the animation at the grow rate, and when we hit the 25%, remove the old 0% mesh, and stop the animation for it. Then spawn in the 25% mesh at its location and call the appropriate functions and have the animations start running.
That is how I would imagine it would work for making grass grow and being influenced by the players. Apologies if this sounds like rambling.
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