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TerrainRiverTool

Options:
use in editor.
use in game.
clear after carve; whether to clear or re-use nodes after carving.

Note: options menu does not update visual until use and restart. But its functions work!

-When subscribed and checked-
A menu will appear in editor with a button called "CreateRiver"
When pushed the menu will disappear and, if aimed at the terrain, a cursor (yellow blob) will show.

By clicking on the terrain nodes can be placed.

If you keep the cursor close to an existing node the cursor will snap to that node; the node is now 'selected'

-When node selected'
Click and drag to change the position of the node.
Hold 'Left Shift' and drag to change the size (width & depth) of the node.
Click right mouse button to delete node.
(At this moment new nodes can not be placed in between existing nodes!)

A Bezier-line will be drawn along the nodes (In order of placement!).

Press the right mouse button (without having a node selected!) to leave editmode and go back the menu.

-Menu-

Edit; To go back to editmode.

LerpHeight; All node heights will be interpolated between start-height and end-height.
After this; nodes can be hidden underneath the terrain.
To get them back: alter the terrain a bit and, if necessary, undo afterwards.

LerpWidth; All node widths will be interpolated between start-width and end-width.

LerpDepth; All node depths will be interpolated between start-depth an end-depth.

(individual nodes can be changed afterwards)

Reset; Deletes all nodes and preview. Don't press it by accident!

Carve; Your river will be created.

TryRiver!; If you have placed only one node. It (kind of) simulates water and finds (most of the time) a way

tip:
If you set all depths to zero; you can also use it to make pathways to build your road on it.
If you set all depths to zero,place start-height and end-height higher, LerpHeights; you can create walls/banks.

My mods are published with code.
If you have more time and skills than me...please steal and improve!