[FREE] Terrain Tools 3 Mixer (Open Source, GitHub)

Terrain Tools 3 Mixer

Mixer for Unity's Terrain Tools 3 is a free and Open Source extension for the Unity Terrain Tools version 3. You can stack and order the provided tools via drag & drop and change the size and opacity of the brushes quickly. During painting the tool stack is painted one after the other.

That way you can create an arbitrary order and use the tool as a road painter, path painter, river and lake bed painter, mountain andvances and so on.

This is an update to its predecessor Path Paint Tool which supports now Unity 2021+. The name got changed to "Mixer" because it'll become more over time with Unity's addition of more Terrain Tools like Terrace, Thermal and Hydraulic Erosion, Twist and even with their awesome filters for Noise.


Let's see in a video how it looks like in action, please click on the picture to see the video on youtube. In the example I use the Mixer for creating a path from scratch for a bike driving scene:


In Unity 2020+ or 2021+ open package manager and install via git url:


Additionally you can download this free unity package which includes a Demo Terrain with Textures (see credits) in order to get you started quickly:


For older Unity versions I recommend Path Paint Tool.


  • Unity 2020+ and Unity 2021.1 ... support for Unity's experimental version of their terrain tools
  • Unity 2021.2 ... support for Unity's release version of their terrain tools

Changes compared to Path Paint Tool

The code was adapted to work with Unity 2020+ and 2021+.

The UI has become more compact. The individual Terrain Tools are quickly accessible and the Brush Size and Opacity can be quickly compared and changed.

To the right of the Terrain Tool Name is the slider for the brush size and next to it is the slider for the brush opacity, i. e. strength. Those values are relative to the overall Brush Size and Strength.




Various features are implemented, most notably:

  • Supported Terrain Tools

Any combination of Paint, Path, Smooth, Ridge Erosion, Smudge, Underlay

  • Various Paint Modes

  • Paint Brush: Paint by dragging the mouse

  • Stroke: Create strokes by placing an anchor point and subsequently create strokes from the previous anchor points.

  • Automatic Waypoint creation and Spline manipulation are in development and will be implemented as soon as Unity releases their Spline Package

  • Create roads, paths, plateaus, ramps, lake and river beds, mountain spurs, ...

  • Multi Tile Terrain

  • Unity 2021.1 and 2021.2+ Support

  • Vegetation Studio Pro Support

  • Open Source, FREE for everyone, no DLL


Integrations which can be used for worklfow automatization

  • Vegetation Studio Pro

For Vegetation Studio Pro I recommend to use the include and exclude terrain texture rules for automatic vegetation placement.

The Idea

Unity created and provided various tools for terrain manipulation for free. When I studied them I figured that it would make sense to combine them. So I tried and implemented a quick tool which combines various Terrain Tools in 1 paint stroke.

So the basic idea is to have multiple brushes overlapping, e. g.:

  • inner brush: texture tool
  • middle brush: path tool
  • outer brush: smooth tool


Multi-Tile Terrain Road & Path Painting



Vegetation Studio Pro Integration


Underlay Paint for e. g. River Beds


Another use case in a video:


The demo unitypackage is provided to get you started with a tiled and textured terrain.


Full credit and a BIG THANK YOU(!!!) to the very skilled and most awesome developers at Unity who provided the Terrain Tool Samples for free for the community.

Demo Scene:

World Creator 2 with which the creation of the demo terrain was possible within minutes. Most of all thank you to Yanik for providing the base terrain.

The textures for the terrain after importing into Unity are Creative Common textures which are freely available and can be used without restriction.

Credit to these providers:


  • Integrate the upcoming Terrain Tools 4
  • Automatic Waypoint finder and shaping the terrain
  • Spline creation, Spline saving and flexible adjustment
  • Additional Terrain Tool support
  • Presets & Quick Access Settings
  • Paint and remove terrain details using Unity's detail painter
  • ...

Just to show what's coming in the future with the Terrain Tools 4: You can add jitter and noise which gives some very useful modifications, e. g. here's a simple star brush used with the Path Tool which jitters during painting and in that way also modifies the mountain edges:


I'll add that to Mixer once the Terrain Tools 4 come out of preview. For now, if anyone is interested in that, feel free to check out this path tool core thread .


Awesome! Thanks a lot for providing this for free. Btw, is it possible to have “grab” or “pinch” tool so that we can make cliff/ overhang easily?


The heightmap is just a 2d image in the end, for cliffs and overhangs you'd need dedicated tools that create a mesh. Sebastian Lague has a free solution for that.

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Thanks for sharing I shall look into that. :slight_smile:

Sorry to bother you, but could you help on how to install it? I inserted the above link into package manager & I got error as below:

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Which Unity version are you using exactly? eg in Unity 2020.3.12f1 you should use this option:


Alternatively there's always the manual way. Just go to the GitHub page, click the green Code button, click "Download ZIP"


and extract the TerrainTools folder of the zip file into your project's Assets folder.

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Thank you! :slight_smile:

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Great tool, Thanks for making it available to us!


I can’t wait for spline integration. I have been trying to make Path Painter tool to work with my spline but the result isn’t that great.

Would love to have a tool that just takes a bezier curve as input and draw that path on top of the terrain so I can choose parameters and carve and paint over it.

You could e. g. use the technique I used here:


Basically it’s a separate bitmap. On that bitmap you paint the spline by iterating along in steps and connect the steps using e. g. a simple Bresenham algorithm. Then you blend the bitmap on the heightmap of the terrain. Embankment could be achieved by e. g. blurring. Or you could use Unity’s own Spline Tools (see their examples), have the road mesh created and blend that on the terrain.

That being said, all effort might be a waste of time tomorrow if Unity announces either the support of that for the terrain tools or better yet they announce the new Environment System.

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That seems like exactly what I needed thank you for that.

@Rowlan you're a champion. I appreciate you making this tool free and open source. Keep up your great work.


Can U please attach a license on github repo like MIT?

The license is listed here:


And since it's based on the Unity Terrain Tools, it's a mixed license including the Unity Companion License.

Rowlan can u do anything for the old problem “terrain texture streching” i.e when raising cliffs and mountains …the textures get streched and looks weird …, Thanks a Lot)

Either use a mesh for that or a shader that supports triplanar UVs.

cant triplanar feature be added on your terrain height blend shader on github?

No. That's part of the material of the terrain.

can you add tools for scale system for terrain i mean i scaling entire all objects in scene include terrains

I moved on to more efficient things than the Unity Terrain Tools :wink:






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