Hi all (okay, probably @Stephen),
A while ago I asked about maya modifying the camera, https://answers.arnoldrenderer.com/questions/20626/control-maya-modifying-camera-attributes-on-camer...
Turns out, mtoa just keeps overriding the translator every time you change the ortho value when you set orthographic to true when the translator type is set to your own camera.
i.e. it's impossible to get your own camera type to be treated as an orthographic camera. If you don't have it set to an orthographic camera, then the translator doesn't export the screen min and max for the ortho bounds, so your camera can't integrate properly with changes in camera size etc.
Which leads back around to the question I asked here https://answers.arnoldrenderer.com/questions/21868/tell-dccs-to-treat-camera-as-orthographic.html
I realize, I could just modify MTOA python scripts, and while yes, that would work for me. This is for a plugin we intend to ship, making that workaround unviable.
What's the proper solution to this? It seems pretty clear this is a bug/deficiency in Maya/mtoa, submitting official support tickets around this issue has literally gotten the response this is out of the scope of their knowledge and to talk to the Arnold support staff, but it's been months and I'm getting nowhere. Somebody at Autodesk needs to take ownership of this and get us a comprehensive, shippable solution.
Further aspects to issues around this are that if you lock the parameter to try force it to remain, the exporter isn't providing all the data you need. In addition, if you use your own translator, registered through the CExtension plugin, which would be needed in order to ensure all the data you want is provided on the Arnold node, then the attribute template, registered through mtioa.ui.ae.templates.registerTranslatorUI will no longer get called back.
So no matter which way you slice and try work around this. It seems impossible to get an othographic style camera registered and exporting in Maya, and custom attributes UIs seem to not be supported with custom translators (using either CCameraTranslator or CAutoCameraTranslator as a base class).
Cheers,
Alan.