Legacy Installation

Unity versions between 2018.2 and 2019.2 are supported by glTFast 1.x, which can be found in the gltfast-1 branch

So the GIT URL you have to install in the package manager becomes https://github.com/atteneder/glTFast.git#gltfast-1 (note the # and the branch at the end).

With older versions of Unity and the Package Manager you have to add the package in a manifest file manually. Add the package's URL into your project manifest

Inside your Unity project there's the folder Packages containing a file called manifest.json. You have to open it and add the following lines inside the dependencies category:

"com.atteneder.draco": "https://github.com/atteneder/DracoUnity.git",
"com.atteneder.gltfast": "https://github.com/atteneder/glTFast.git#gltfast-1",

It should look something like this:

{
  "dependencies": {
    "com.atteneder.draco": "https://github.com/atteneder/DracoUnity.git",
    "com.atteneder.gltfast": "https://github.com/atteneder/glTFast.git#gltfast-1",
    "com.unity.package-manager-ui": "2.1.2",
    "com.unity.modules.imageconversion": "1.0.0",
    "com.unity.modules.imgui": "1.0.0",
    "com.unity.modules.jsonserialize": "1.0.0",
    "com.unity.modules.unitywebrequest": "1.0.0",
    "com.unity.modules.unitywebrequesttexture": "1.0.0"
  }
}

Next time you open your project in Unity, it will download the packages automatically. There's more detail about how to add packages via GIT URLs in the Unity documentation.

Draco support

If you use Unity older than 2019.1 and glTFast with DracoUnity, you additionally have to add DRACO_UNITY to your projects scripting define symbols in the player settings.

Trouble shooting

If you run into an error like com.atteneder.gltfast: Version is invalid. Expected a pattern like 'x.x.x[-prerelease]', got 'https://github.com/atteneder/glTFast.git' instead.:

This is a legacy Unity bug. A workaround would be to make a local clone of the gltfast-1 branch and add it via a local path (see the documentation).