Horde3D

Is there anyway to add attachments without a plugin? Like raw text or something?

Also does anyone run the editor using plugins on Linux? All the plugin configuration I've found refers to .dll files.

I thought about it some years ago but never implemented anything like that. Since the GameEngine was something that was only compilable under Windows for a long time I never did any tests with plugins under Linux. But in theory there shouldn't be any problem to use plugins under Linux too.

So how do the plugins actually work? I see where you point to a plugins folder in the editor's settings, which is where I've placed my linux compiled .so files, but it doesn't seem to be bringing anything in.

In the the SVN repository, there is this file: http://mm-werkstatt.informatik.uni-augsburg.de/public/Horde3D/trunk/Tools/Horde3DEditor/bin/plugin.cfg which refers to a bunch of plugin dlls. Where does this file go? Is it still necessary?

There are two types of plugins: the editor plugins that are using Qt's plugin mechanism and the GameEngine's components which are using the plugin.cfg file. I'm not sure if it's still be used. Maybe nuschii can tell you something about it, since he mentioned that he ported the GameEngine to linux some time ago.
The Qt mechanism should try to load editor plugins from the folder configured in the editor settings. AFAIK if there is an error during the loading there should be an error message in the console.

Yeah I have the .so plugins in that folder, but I'm not seeing anything in the logs referring to loading or erroring out plugins, and I'm not seeing anything under the Tools menu, and the add attachment menu option is always grey'd out.

I'll start looking through the source and see if it's looking specifically for .dll's or something.

Nope, it looks like it's looking for .so files on linux:

Returns true if fileName has a valid suffix for a loadable library; otherwise returns false.

From: http://cep.xor.aps.anl.gov/software/qt4-x11-4.2.2-browser/da/d77/class_q_library.html#401854f4aeeeb725d104d14f08bfb16a

Regarding the Add attachment gray out, you have to activate a plugin when creating a new scene. The last wizard page should list all available plugins. Did you have implemented the AttachmentPlugins interface in your plugins like it is done in the GameControllerAttachment.h/.cpp ?
Check especially the Q_EXPORT_STATIC_PLUGIN and Q_EXPORT_PLUGIN2 statements in your cpp file. Otherwise the Qt plugin loader won't be able to load your plugin.

For scene node enhencements there is the ExtSceneNodePlugIn interface and for Tools you have to implement ToolPlugIn interface.