*dynamically resize water entities
*split water entities -> two from one
---than remove one on side of ditch
*join water entities -> one from two
---remove extra
*tile system
---raise lower terrain in chunks
---smooth chunks for hills / ditches (ramp procedure)
---save out to hmp / mdl format
*system to store water entity chunk states (with tile system)
---3d bounding checks (cube, etc.)
---on raise
------if intersection
----------split water entity
----------two from one
----------scale / translate two water entities
Other than that:
Quoting Michael_Schwarz.