[vtkusers] vtkImageMapper

[David Doria]

> When I ran the example, I saw a small 20x20 red-and-green image in the
> corner of the window, just like I would expect.  Your image is just a
> little small, I think.
>
> The vtkImageMapper is a 2D mapper, which means that it uses display
> coordinates.  In display coordinates, one image pixel is always one
> screen pixel.  So you should get rid of the call to ResetCamera(), the
> camera settings have no effect on the display of 2D actors.
>
> Also, just to be clear on this point, the vtkImageMapper is not
> deprecated.  It is a 2D mapper for displaying images in display
> coordinates.  In contrast, the vtkImageMapper3D classes are for
> displaying images in world coordinates.
>
>  - David

Thanks for the explanation David! I added a note to that effect in the
documentation:

http://review.source.kitware.com/#change,2857

David