DLL not loaded in editor

[Wouter De Keersmaecker]

Hi, thank you for your work on this library!

I’m working on a custom inspector panel in Unity that allows our artist to load some stuff from an FBX file into the Unity Editor. Unfortunately, it seems this library doesn’t work properly at edit-time? Calling ImportFile produces a COMException with the note that the DLL was not loaded. Upon further inspection, it seems that the initialization code in AssimpUnity.cs is only loaded at runtime, but not in the editor.

I fixed this by adding

#if UNITY_EDITOR
    [UnityEditor.InitializeOnLoad]
#endif

to the class, and then adding a static constructor which calls InitializePlugin. This makes sure the DLL loading code is run in the editor too.

[Wouter De Keersmaecker]

During initialization, AssimpUnity also seems to assumes the plugin files are at “app/Plugins/AssimpNet/Native”. However, if this library is part of a package, this path is incorrect in the editor which causes the dll load to fail.

I fixed this with the following snippet:

if(!Directory.Exists(editorPluginNativeFolder))
{
    // Get directory that contains this file.
    string pluginFolder = Path.GetDirectoryName(GetCallerFilePath());

    pluginsFolder = Directory.GetParent(pluginFolder).FullName;
    editorPluginNativeFolder = Path.Combine(pluginFolder, "Native");
}

where GetCallerFilePath is defined as

private static string GetCallerFilePath([System.Runtime.CompilerServices.CallerFilePath] string filepath = "")
{
    return filepath;
}

I can make a PR if you want.

[Nicholas Woodfield]

Thanks for investigating! Please go ahead and make a PR

[Wouter De Keersmaecker]

OK, I made a PR at https://bitbucket.org/Starnick/assimpnet/pull-requests/3/initialize-on-load-in-unity-editor-added