Neither ITK or SimpleITK are visualization tools. They are primarily image analysis tools with ITK also supporting mesh operations.
If you need to visualize images and meshes, then you should save the images and meshes in standard formats and load them into a visualization program (e.g. Slicer or MITK workbench). This can be done programmatically (e.g. write code in vtk) but is not recommended if you are not already familiar with the visualization toolkit you choose to use (significant effort).
Thanks for response ! I understand that i need external viewer, but i want just to display scrollable data fir fast prototyping of the algorithms, slicer3d would be ok if it can be integrated.
What i mean is execute some line of code see the results execute another see change in results etc
I don’t think napari can visualize 3D meshes. In general, its 3D visualization capabilities are still very limited (it does not even have the basic view with 3 orthogonal slices + 3D view) and its main strength is in displaying large 2D/2.5D microscopy images.