[vtkusers] Problems building vtk (nightly update) on cygwin

[Roger Blum]

Hello vtk users,

I have tried to build the nightly update of vtk with tcl wrapping under 
cygwin.

ccmake .
BUILD_EXAMPLES                   ON
BUILD_SHARED_LIBS                OFF
CMAKE_BACKWARDS_COMPATIBILITY    2.0
CMAKE_BUILD_TYPE                   Win32-cygwin
CMAKE_INSTALL_PREFIX             /usr/local
VTK_DATA_ROOT                    /home/Roger/VTKData
VTK_USE_CG_SHADERS               OFF
VTK_USE_GLSL_SHADERS             OFF
VTK_USE_PARALLEL                 OFF
VTK_USE_RENDERING                ON
VTK_USE_X                        ON
VTK_WRAP_JAVA                    OFF
VTK_WRAP_PYTHON                  OFF
VTK_WRAP_TCL                     ON

When i execute make, I get the following error message:
...
Building object file vtkTkRenderWidget.o...
/home/Roger/VTK/Rendering/vtkTkRenderWidget.cxx: In function `LRESULT 
vtkTkRenderWidgetProc(HWND__*, UINT, WPARAM, LPARAM)':
/home/Roger/VTK/Rendering/vtkTkRenderWidget.cxx:796: error: invalid use of 
undefined type `struct _XDisplay'
/usr/X11R6/include/X11/Xlib.h:289: error: forward declaration of `struct 
_XDisplay'
make[3]: *** [vtkTkRenderWidget.o] Error 1
make[2]: *** [default_target] Error 2
make[1]: *** [default_target_Rendering] Error 2
make: *** [default_target] Error 2

What am I doing wrong? What do I have to change?

Regards,
Roger