[vtkusers] vtkImageViewer2 image display

[Oleksandr Dzyubak]

vtkusers-request at vtk.org wrote:
> Date: Fri, 4 Apr 2008 02:11:46 -0700 (PDT)
> From: tobse <tobias.meisel at phacon-leipzig.de>
> Subject: Re: [vtkusers] vtkImageViewer2 image display
> To: vtkusers at vtk.org
> Message-ID: <16489656.post at talk.nabble.com>
> Content-Type: text/plain; charset=us-ascii
>
>
> Hi,
>
> I calculated the FocalPoint and the Position of the camera with respect to
> the image size
>
> 1. determine the size of the image in x and y direction (using the extent
> and the spacing of the input image)
> 2. based on the larger axes, you can modify the view angle or the distance
> of the camera
>   
>             angle = Camera->GetViewAngle();
>             distance= SizeOfLargerAxes/2/tan(angle/2);
> 3. Determine the middle of the image
> 4. Focus the camera to the middle of the image 
>
>       
>             Camera->SetFocalPoint(xmax/2, ymax/2, 0);
>              Camera->SetPosition(xmax/2,ymax/2,distance);
>
> This will work as long as the image is in the xy-plane , with z=0.
>
> hope this will help
>
> tobse
>   
Hi Tobias,

Thanks for your answer.
I understand that the remedy against getting my image in a render window
so tiny is to preset the focal points and position before calling 
methods below.

viewer->Render();
renderWindowInteractor->Start();

I try to use vtkImageViewer2 class and as a starting point
I use the slightly modified code from GettingStarted-II attached below.
Searching the classes used in the code, I cannot find where I could
access the camera methods to preset the values.

Where is it?

Thanks,

Alex


#include "itkImage.h"
#include "itkImageFileReader.h"
#include "itkImageToVTKImageFilter.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkImageViewer2.h"

int main( int argc, char **argv) {
typedef itk::Image <signed short, 3> ImageType;

typedef itk::ImageFileReader <ImageType> ReaderType;
typedef itk::ImageToVTKImageFilter <ImageType> ConnectorType;

ReaderType::Pointer reader= ReaderType::New();
ConnectorType::Pointer connector= ConnectorType::New();
reader->SetFileName( argv[1]);
connector->SetInput( reader->GetOutput() );
vtkImageViewer2* viewer= vtkImageViewer2::New();

vtkRenderWindowInteractor* renderWindowInteractor =
vtkRenderWindowInteractor::New();

viewer->SetupInteractor( renderWindowInteractor);
viewer->SetInput( connector->GetOutput() );

viewer->SetSlice(3);
viewer->SetSize(300, 300);

viewer->Render();
viewer->SetColorWindow( 255);
viewer->SetColorLevel( 128);

renderWindowInteractor->Start();
return 0;
}