Zoom Sample
Source code for Zoom sample is available in Samples\VC  folder of the installation directory. It is recommended to 
copy whole VC directory to location outside of the installation folder
before loading or compilation. Zoom sample demonstrates  manipulation of
.viewing volume using ILook
 interface. It also demonstrates manipulation of the Eye frame
with the help of it IFrame interface  
See also C# .NET Samples,  All samples 
The application  
The "Center of zoom" group allows entering a point in pixels with
respect to which zoom operation will be performed. "Translate Eye
Frame" group allows manipulation of the vieving plane 
Implementation
All implementation is contained in the main form class named CZoomDlg. 
CZoomDlg::OnZoom() handler converts screen coordinates of the zoom center to
global 3D coordinates using ILookEx.creenTo3DEx.
The point has to be converted to loca to the Eye frame to use the ILook.ZoomEx
method. This is accomplished via IFrameEx.ToLocal.for
the IFrame of the Eye Frame. 
  
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