How to do "Annotation&Measurement" on MPR?

How to do “Annotation&Measurement” on MPR like MITK or 3D Slicer?

Both MITK and Slicer are VTK-based open-source software with restriction-free license, so you can use them or copy-paste any code from them as you see fit.

If you only need to make measurements in a single view then you might do away with stock VTK widgets, otherwise it probably makes more sense to use/customize/extend MITK or Slicer. Both these application frameworks are developed to serve as a basis for custom applications.

sorry, I thank it is too complex, I want an simple VTK widget,like vtkLineWidget,vtkDistanceWidgete,etc.

There is no place for simple desktop applications anymore: that field has been taken over by web applications. You would have really hard time convincing anybody nowadays to install a desktop application for doing simple tasks, because users expect they can do simple tasks anywhere, anytime, on any device, without installing anything.

If you are completely sure that your application GUI will never evolve to be anything more complex then I would recommend to implement a web application using VTK.js.

If you want to develop sophisticated desktop applications then it is probably worth learning an application framework that people in your field use to avoid design, development, support, and maintenance workload.

thank you very much! And I want to know How it draw a line when I using the vtkLineWidget and vtkLineRepresentation. I can’t find the source code like drawing from one point to another. Do you know?