
How to build and run FreeCAD under MSYS/MinGW
=============================================

Prerequisites
-------------

Here comes a short introduction how to setup a MSYS/MinGW environment
on a Windows system, to build all needed libraries and finally to build
the FreeCAD sources.

o MSYS/MinGW
If not already installed get a MinGW installer from the Sourceforge page at
http://sourceforge.net/projects/mingw. When writing this tutorial the latest
version was mingw-get-inst-20100831.exe. Download and just double-click the
excutable. This installs the compiler and a minimal Windows developer environment.
Make sure to also install the Fortran compiler because there is a single Fortran
file in the 3rd party folder of the FreeCAD sources.

Then as second step MSYS needs to be installed to have an environment to run
./configure scripts which we make heavy use of in order to build all needed
libraries. From the Soureforge page the file MSYS-1.0.11.exe was taken.

A virginal MSYS/MinGW installation lacks of a few modules we later need.
First, we need the utility pexport which can be found in the file
pexports-0.44-1-mingw32-bin.tar.lzma. I don't know where to put this file
and how to make MSYS to install the stuff inside. But the file can be opened
with a ZIP program and the content can be copied to their destination manually.
Here, the pexports utility can go to the bin directory of your MinGW installation.

Then, we also need the development files for the pthreads module which is part
of the file pthreads-w32-2.8.0-3-mingw32-dev.tar.lzma. Just download and copy
the files inside to your MinGW installation.


o CMake
Download the CMake utility from http://www.cmake.org/cmake/resources/software.html.
Get the archive with the binaries for the Windows platform and unpack whereever you
want. There is nothing further to do for this.

o SWIG
Download the SWIG utility from www.swig.org and extract it somewhere on your harddisk.


Third party libraries
---------------------

Here is a description which libraries we need for FreeCAD and how to build them from
the sources. In order not to pollute our MinGW installation with too many files from
the 3rd party libraries we have to build you can e.g. create a sub-directory "local"
in your MSYS installation. If you have installed MSYS under C:\MSYS then simply create
the directory C:\MSYS\1.0\local.


o zlib
For zlib there is already a ready package for MinGW. So, therefore simply download
the file libz-1.2.3-1-mingw32-dev.tar.gz from the Sourceforge site and extract the
two directories lib and include to C:\MSYS\1.0\local.


o Python
It seems to be nearly impossible to build the Python sources directly with the MinGW
compiler. This is because some Python modules require some features which are not
implemented on the MinGW platform. Fortunately, the Python sources are plain C code
and instead of trying to build it with MinGW you can get a ready binary package built
with the MSVC compiler. You can install the Python stuff whereever you want. Afterwards
copy the include folder to C:\MSYS\1.0\local, the DLL can go to C:\MSYS\1.0\local\bin.

Now we also need the so called import library. There we cannot use the .lib file which
comes together with the installer. But it's easy to create one with the pexports/dlltool
utilities. Assuming the Python version is 2.6 do these two steps:

  pexports python26.dll > python26.def
  dlltool -D python26.dll -d python26.def -l libpython26.dll.a
  
The file libpython26.dll.a can now be moved to C:\MSYS\1.0\local\lib.


o f2c
For this library we don't need any header files but only the import library to build the
Salome SMESH sources. The easiest way to build this file is:

  pexports libgfortran-3.dll > f2c.def
  dlltool -D libgfortran-3.dll -d f2c.def -l libf2c.dll.a

The file libf2c.dll.a can now be moved to C:\MSYS\1.0\local\lib.

  
o xerces-c
Download a source archive from http://xml.apache.org/dist/xerces-c/ and extract it.
Open a MSYS command line window and change to the xerces-c sources. From there run

 ./configure LDFLAGS=-no-undefined 

Once ./configure has finished it's best to move to the source directory because we
don't need to build the dozens of test applications and other stuff. So, do this:

  cd src
  make
  make install
 
This takes a few minutes to be done.


o boost
For boost there exists a testing package with cmake support. This, however, seems to be
stable enough to build with the MinGW compiler. So, get the file boost-1.41.0.cmake0.zip
from http://sodium.resophonic.com/boost-cmake/1.41.0.cmake0/ and unpack it.

Now, start the cmake-gui.exe from within the MSYS command line. This is necessary for cmake
in order to find the compiler and other stuff. Select the folder of the boost sources with
the CMakeLists.txt file, select a build directory and start Configure. You'll be asked for
which system you want to generate the Makefiles. Select MSYS/Makefiles, not MinGW/Makefiles.

When the configuration step has finished go to the options and search for WINMANGLE_LIBNAMES.
Switch this off because otherwise the boost library names contain the compiler name. This
causes the boost cmake check to fail later when we try to build the FreeCAD sources. And for
the installtion folder choose the directory C:\MSYS\1.0\local.

So, reconfigure boost and press on Generate once it has finished. Close the CMake GUI window
and enter

  make
  make install

into the command line. This will take a couple of minutes.


o eigen2
Download eigen-2.0.15.tar.gz or any later version from http://eigen.tuxfamily.org/index.php?title=Main_Page.
Unpack the files and start again cmake-gui. Set the installation directory to C:\MSYS\1.0\local
and press on Configure and Generate. Close the window and start the installation with

  make
  make install


o Qt4
From the Qt website at ftp://ftp.trollech.com you can download already prebuilt packages for the
MinGW platform. But depending on the version you have installed it can happen that they don't fit
together. In this case the source tarball must be downloaded. Use version 4.5.3 or higher. Unpack
the sources and start the configure.exe you'll find inside the sources.

  ./configure
 
By default the build the debug and release version. If you only want the release version use the
option "-release". 
  
Configure will ask you some questions under which license you want to use Qt. Choose LGPL here. 
Now run the build with
  
  make
  
This can take quite some time because Qt has become a really huge library over the years. Once the
build has finished run a

  make install
  
to copy the header files to their right place. All the binaries and header files are still inside
the source folder. If you like you can copy all the .dll, .a, and the direcories under "include" to
the subdirectories of C:\MSYS\1.0\local.


o Coin
Get a source archive from www.coin3d.org. Unpack the sources and run

  ./confiure
  make
  make install

It may happen that a message dialog pops up due to a missing cygwin1.dll. You simply ignore this.


o SoQt
Get a source archive from www.coin3d.org. Unpack the sources and run

  ./configure CXXFLAGS="-DCOIN_DLL" --with-qt=/usr/local
  make
  make install

In case your Qt development files are not under /usr/local choose the correct directory there.
Again a message dialog may pop up due to the missing cygwin1.dll.


o PyQt/sip
Download the sources archives for sip and PyQt4 from www.riverbankcomputing.co.uk.

In order to build sip extract the archive and open a MSYS command line. From within
its source archive call

  python configure.py --platform win32-g++ --destdir=/usr/local
  make

It may happen that this step aborts because the Python include headers cannot be found.
In this case edit the Makefile and add the include path for the ython headers and also
the path and filename of the Python library.

Unfortunately, the 'make install' command doesn't work because the Makefile was generated
to use Windows batch commands instead of bash commands. Thus, copy the following files to
a path where Python can find it, e.g. /usr/local/bin.

  sipconfig.py
  sipdistutils.py
  siputils.py
  sip.pyd
  sip.exe

In order to build PyQt4 extract the source archive and open a MSYS command line. Go to the
directory and start

  export PATH=/usr/local/lib/:$PATH
  python configure.py --destdir=/usr/local/lib/site-packages
  make

Since the Makefile doesn't find the Python header files copy them all and also the file sip.h
to a directory where they can be found. A good place seems to be the directory of the Qt sources.
There copy the files to $QTDIR/include. The Python library file python26.dll.a can go  $QTDIR/lib.

After the build has finished you have to copy all files that end with .pyd to their destination,
e.g. /usr/local/lib/site-packages/PyQt4. Lateron when you have built the FreeCAD sources you have
to copy the PyQt4 directory and sip.pyd to the FreeCAD bin directory or set a symlink.


o ODE
TODO: Still not clear if this will be used. (http://www.ode.org), >= 0.10.x


o OpenCASCADE
For the build of the OpenCASCADE libraries get the sources from www.opencascade.org or alternatively
it is also possible to download a stripped source tarball from the Debian mirrors which don't include
any fonts and other resource files.

Unpack the sources and download a CMake script from http://opencascade-cmake.googlecode.com/svn/trunk/
and the file occ_config.h.cmake. Copy both files into the 'ros' directory, start cmake-gui from
within a MSYS command line and select MSYS Makefiles. In the options  the following switches can be
disabled:

  OPENCASCADE_WRAPPERS
  OPENCASCADE_VISUALISATION
  OPENCASCADE_OCAF
  OPENCASCADE_DRAW
  
Then specify for OPENCASCADE_INSTALL_PREFIX C:/MSYS/1.0/local as destination directory-

Now click the Configure button which takes a while and afterwards the Generate button.

Note: The original sources don't completely compile with MinGW. Therefore you have to apply the patch
      OpenCASCADE6.3.0-MinGW.patch from http://code.google.com/p/opencascade-cmake/source/browse/trunk

Note: The original sources includes also a configure script and the Makefile.am files.
      But it appeared to be very hard to build the libraries this way. Thus, it highly
	  recommended to do it the CMake way.

Note: For a couple of libraries the arguments passed to the linker exceeds the number of
      allowed characters and thus the linker stops with an error: "Bad file number".
	  To solve this issue you can open the file build.make of the according library and
	  split the block (e.g. TKGeomAlgo_OBJECTS) into several smaller ones and modify the
	  build rule this way that you create first a static library, add the other object
	  files to the group and then unpack the static archive into one directory. This
	  trick solves the problem to reduce the whole number of characters.
      Afterwards the shared library can be built out of these object files.
      Example:
      If the build.make file has a line of the form
        g++ <options> -shared -o libTKGeomAlgo.dll $(TKGeomAlgo_OBJECTS) <libs>
	  then change it into
	    ar rcs win32/libTKGeomAlgo.a $(TKGeomAlgo_OBJECTS1)
	    ar q win32/libTKGeomAlgo.a $(TKGeomAlgo_OBJECTS2)
	    ...
	    ar x win32/libTKGeomAlgo.a
        g++ <options> -shared -o libTKGeomAlgo.dll *.obj  <libs>
		rm -f *.obj


Building the FreeCAD sources
----------------------------

In order build the FreeCAD sources either get the developer sources from the SVN repository
or get one of the .tar.gz tarballs and extract it.
Now start cmake-gui.exe from within a MSYS command line window and browse to the FreeCAD
sources and also define the build directory. Now run Configure. It may happen that cmake
complains about some not found libraries. In this case go through the listed libraries and
choose the include directory and/or the path to the library where needed. Once Confgiure
accepts all your input create the Makefiles by clicking on Generate. Now close the window
and enter

  make
  make install

This will take a couple of minutes. From the command line window change to the FreeCAD bin
folder and start the application with ./FreeCAD. In case it complains about some DLLs it cannot
find you have to extend your PATH environment variable with

  export PATH=$PATH:/usr/local/bin:/usr/local/lib

If no grave problems remains repeating ./FreeCAD should start the application now.

Note: In order to let CMake detect the boost libraries you must make sure that the
      DLLs are in the system path because the check builds some test applications
      and tries to start them. If the DLLs are not in path CMake says that it cannot
      find boost. In this case do a export PATH=/usr/local/lib:$PATH

Have fun!
