WPF 3D - How can I save and load a Camera view?

Question

I have a WPF 3D scene where I can pan, rotate and zoom using the TrackballDecorator from the 3DTools library. I would like to save the camera settings (transformation) and be able to re-apply them when the application restarts the next time (so the view is restored).

I tried to save each individual value of the Camera:

private void SaveCameraSettings()
{
  var d = Properties.Settings.Default;
  d.CameraPositionX = camera.Position.X;
  d.CameraPositionY = camera.Position.Y;
  ...
  d.Save();
}

This doesn't work, I guess because those settings are not updated according to the transformations applied to the camera (I always get the initial values set in xaml).

I checked the the Transformation3D class but couldn't find any way to set its value...

The problem is what values do I need to get from the PerspectiveCamera in order to be able to restore it the way it was when I closed my application the last time. The camera is set to a default position (in Xaml), then a transformation is applied to this camera by the TrackBallDecorator. How can I save this transformation (what values to store)? And how can I re-apply them at a later time?

Answer 1

You would need both the cameras view matrix data and the projection matrix data. The view matrix will contain the data about the position, rotation, scale and translation of the camera and the projection matrix will contain things like the field of view, near plane, far plane and other data.

Sorry I cant help with exporting/importing that data since I've not used WPF, but there might be rawdata properties exposed if it uses anything to do with as3's built in Matrix classes, this is usualy a as3 Vector. Object the the matrices 16 values exposed as row ordered floating point values.