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** WARNING: There is absolutely no warranty for this software **
** package. See the file COPYING for details.                 **
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                           Graphics::VTK
                           Version  4.0.001
                                by
                           Roberto De Leo
                               and
                           John Cerney
                        [email protected]

 What is it?
 -----------
 Graphics::VTK  is a module that allows you to call VTK (Visualization
 ToolKit) functions from a perl script. The Visualization ToolKit is
 an open-source 3D Graphics Visualization library available at
 www.kitware.com.

 Graphics::VTK is designed to work similarly to the  TCL bindings
 that come with the stock VTK package. For example, Perl Tk Widgets are provided that
 interface with VTK, similar to the tcl/tk widget interfaces provided with
 the stock VTK.


 Prerequisites
 -------------

 You need to install two packages before trying to compile this:
 - the Tk module, that you can get from http://www.cpan.org
 - the VTK library, version 4.0, that is freely available
   from ftp://public.kitware.com/pub/vtk/vtk4.0
   (Version 4.0 is of VTK is required, not version 3.1, or 3.2.
   Graphics::VTK 4.0.001 is specifically for VTK version 4.0.)

 To test the module, you will need the VTK test data available
 at www.kitware.com. Once you have this data installed, set
 the environment variable VTK_DATA_ROOT to point to the installation
 path of this data. For example, if you extracted the vtk data
 to /home/mydir/vtkdata, set VTK_DATA_ROOT=/home/mydir/vtkdata


 Installation
 ------------

 First of all, you should modify the file VTK.config according to your
 system. Example files are provided that a known to work with Redhat 7.1,
 Solaris 2.6.1, and win32 (with the mingw compiler on win32). Note
 that the installation process is slightly different from the standard
 perl module compilation because we have to use a C++ compiler. Perl
 modules typically use a C compiler.

 Then you can now start the compilation with the standard

 perl makefile.PL
 make
 make test
 make install

 WARNING: during the compilation, consumption of memory arrives to ~200Mb
 so do not try to compile this module if you do not have enough RAM+Swap

 Note: As of this release. This package has been successfully built and
 tested on Sun Solaris, Linux (Red Hat 7.1, 7.3), and Windows NT (using mingw32
 compiler).

 Testing
 -------

 With the VTK data installed (see Prerequisites section), this package
 is tested by running a set of example scripts that are known to work.
 See the examples/README file, or the test.pl script itself for a list
 of these scripts. These test scripts are interactive, so you will
 have to view the results and exit-out of each test as they are run.

 Example Scripts
 ---------------

 The example tcl scripts from the VTK 4.0 distribution have been converted
 to perl and placed in the following directories under the 'examples' dir:
 Annotation, DataManipulation,GUI,  ImageProcessing, IO, Modeling, Rendering,
 Tutorial, VisualizationAlgorithms, VolumeRendering.

 Documentation
 -------------

 Detailed documentation of the VTK package is available at the VTK
 web site at http://www.kitware.com. The documentation included in this
 package details which object methods are  supported. After
 installing type 'perldoc VTK', or perldoc 'Graphics::VTK::Common', etc,
 to access these docs.


 VTK Versions and Graphics::VTK Versions
 ---------------------------------------

 Due to differences between c++ methods of different VTK versions,
 Graphics::VTK versions are closely tied to a particular VTK version.
 For example, Graphics::VTK 4.0.001 is written to work with VTK 4.0
 only. Similarly, Graphics::VTK 3.2.001 is written to work with VTK 3.2
 only.

 Note that any scripts you write using Graphics::VTK 3.2.001 should
 still work with any new releases (version 3.2.001, or 4.0.001),
 unless you are using some feature of VTK that has changed between
 VTK 3.2 and 4.0.


 Known Issues
 ------------
 Under some conditions, perl/VTK will deadlock (i.e. freeze/hang-up) when
 performing i/o operations using C++ streams. This has been observed for
 the using glibc/gcc on a redhat linux 7.2 platform, where the
 supplied perl was not linked against the pthread library. (libpthread
 doesn't show up when performing a perl -V).
 As a work-around, the LD_PRELOAD environment variable can be set to
 fix this problem. i.e. before running perl on the command line (or
 in your .bashrc file) type the following:
 export LD_PRELOAD=libpthread.so