How to make all the content fit the size of viewport3d automatically?

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C#

WPF

I have a ViewPort3D, Which has been inserted many objects. the ViewPort3D has its width and height defined. how can I make the objects displayed wholly inside the width and height


I am Adding all 3D shapes in this viewport3D and whenever I add new object which is bigger than the height and width of viewport I have to rotate the whole 3D scene to look for the object ....is there any solution to it?please suggest any solution –

What I have tried:

this is my camera of viewport3D

<PerspectiveCamera x:Name="camera" FarPlaneDistance="100" LookDirection="0,0,-10" UpDirection="0,1,0" NearPlaneDistance="0" Position="0,0,7" FieldOfView="50" />