Do you mean, how to build a branch on the NvPhysX/UnrealEngine.git fork? There are some instructions in the README for each branch. For example:
Welcome to the HairWorks branch of the NvPhysX fork of Unreal Engine source code!
HairWorks implements physical hair simulation using DirectX Compute.
To build the HairWorks branch, using a git shell:
git clone .git
{wait until it’s done}
cd UnrealEngine
git branch -t HairWorks origin/HairWorks
git checkout HairWorks
.\Setup.bat
.\GenerateProjectFiles.bat
.\UE4.sln
{Build UnrealEngine solution}
{Run the editor.}
Editor Usage:
A new component called Hair Component is added to hook up hair assets into Blueprints. To use a hair asset to a Blueprint, please follow these steps:
• Import hair assets into Content Browser.
o Right click in the Content Browser, use Import to option to select one or more hair asset files, which are usually .apx or .apb exported from 3ds or Maya using HairWorks plugin.
• Open or create a Blueprint. In the Blueprint editor, create a Hair Component. Usually the hair component is attached under a skeletal mesh component.
• Assign an imported hair asset to the Asset/Hair property.
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