0 error description
Error in VTK-6.3.0 using VTKVolumerayCastMapper for volume rendering:

Generic Warning: In D:\VTK\VTK-6.3.0\Rendering\Volume\vtkRayCastImageDisplayHelper.cxx, line 20
Error: no override found for 'vtkRayCastImageDisplayHelper'.

1 Solutions
At the beginning of main() add:

VTK_MODULE_INIT(vtkRenderingVolumeOpenGL);

2. Solution Process
How do you know the above VTKrenderingVolumeOpenGL?In VTK Error: No Override Founds for ‘VTKVolumetTextureMapper2D’, a method is already provided, but there are some difficulties in practice. Here is a better method. Here are the detailed steps.
(1) Find a case of VTKVolumerayCastMapper through the help document of VTK-6.3.0:

(2) Find the directory of Medical4.cxx (VTK-6.3.0/Examples/Medical/) in the VTK-6.3.0 source code. There is a cMakelists.txt file in it:

(3) Open the above cmakelist.txt file and find the contents of the find_package section:

VTKRenderingVolume $(VTK_Rendering_Backend) is the module required for VTKVolumerayCastMapper. So what is the value of VTK_RENDERING_BACKEND?
(4) open the VTK 6.3.0/Rendering/Volume/CMakeList. TXT, in its final value judgment about VTK_RENDERING_BACKEND:

So you can guess that VTK_RENDERING_BACKEND refers to a version of OpenGL, either OpenGL or OpenGL2. OpenGL is used by default in VTK-6.3.0 (VTK-7.0.0 has been changed to OpenGL2), so the value of VTK_RENDERING_BACKEND is OpenGL or OpenGL2, and the former is chosen in this paper.