How to enable Chaos

The plugin isn’t installed by default in 4.25. You need to :

  • Download 4.25 on Github and place it in a folder that is close to your disk’s root (if the path is too long, the download/compilation will fail)
  • Modify the UE4Editor.Target.cs file located in YourDisk\YourPathToTheEngine\UnrealEngine-4.25.3-release\Engine\Source\UE4Editor.Target.cs by adding these lines to build & activate Chaos :

bCompileChaos = true;
bUseChaos = true;

**I did not follow the documentation, I did not replace


BuildEnvironment = TargetBuildEnvironment.Shared;

with


BuildEnvironment = TargetBuildEnvironment.Unique; 

because it doesn’t work.**

  • Build the engine
  • Launch it from Visual Studio by debugging or use YourDisk\YourPathToTheEngine\UnrealEngine-4.25.3-release\Engine\Binaries\Win64\UE4Editor.exe and create a new project
  • This is normal if you can’t launch the project. In this case, open the file YourDisk\PathToYourProject\YourProjectName\Source\YourProjectEditor.Target.cs and add :

bCompileChaos = true;
bUseChaos = true;

(That’s another thing you can’t find in the documentation…)

  • Save the file, restart the editor, launch the project, and then you have to go in the plugins manager to activate all these plugins :

  • Chaos Editor

  • Chaos Solver

  • Chaos Niagara

  • Planar Cut

  • Editable Mesh

  • Geometry

  • Geometry Cache

  • Field System

    • Restart the editor to activate the plugins
    • Open the fracture mode using the buttons I circled in red in the screenshot.

About using it for a project, it’s not recommended in 4.25. Use 4.26 instead.