Pass ClientContext from Unity to plugin to RenderManager

[Greg Aring]

In reference to: ca5227c

Given the declaration:

extern "C" OSVR_ReturnCode EXPORT_API CreateRenderManagerFromUnity(OSVR_ClientContext ctx)

And in Unity:

[DllImport(PluginName, CallingConvention = CallingConvention.StdCall)]
private static extern Byte CreateRenderManagerFromUnity(IntPtr /*OSVR_ClientContext*/ ctx);

(@JeroMiya has noted that the IntPtr above should be a SafeClientContextHandle which is currently not exposed. SafeClientContextHandle maps to OSVR_ClientContext.)

What is the proper way to cast OSVR_ClientContext so that it can be passed to RenderManager::createRendermanager ?:

RenderManager *createRenderManager(clientkit::ClientContext &context
    , std::string displayConfigJsonFileName
    , std::string pipelineConfigJsonFileName)

[Rylie Pavlik]

ah, so that clientkit::ClientContext is the C++ wrapper around the client context. Trying to think if I can make a non-owning constructor.

[Greg Aring]

After @JeroMiya changed the render manager to use the client kit C api, I'm able to successfully pass a ClientContext from Unity and create a RenderManager.

Wasn't having success passing an IntPtr, so I also added a property in Managed-OSVR ClientKit.cs:

public SafeClientContextHandle Context
{
    get { return m_context; }
}

I can push this to Managed-OSVR if this is acceptable.