Re: [Opengc-devel] Compiling the latest version of openGC with CYGWIN

[Damion S. <da...@op...>]

Hi,

Please go ahead and send the detailed information on the linking
errors. I tested the CVS version under both Windows (Visual Studio) and
Mac (gcc) and they both compiled & linked without problems.

Offhand, I suspect that the linking problem is related to how CMake
does or does not detect Cygwin as a valid Unix/Win32 system. Is the
_WIN32 symbol defined during GCC compiles under Cygwin? Right now, the
logic is set up something like:

Is the system Win32?
    Yes. Use Windows OpenGL API.
Is the system Unix?
    Is it a Mac?
      Yes. Use the Carbon GL framework.
      No. Use the X11 GL framework.

I have used cygwin very little, and from what I've read online, _WIN32
is not defined as a valid compiler symbol under GCC in cygwin. This
means that the system would detect the OS as Unix, but not Mac, and
would try to use the X11 GL libraries (which is not correct either).

Some additional poking around suggests that the following procedure may
work, though I have not tested it. CMake is used to build the
Visualization Toolkit as well, and it sounds like similar linker errors
were encountered. Their solutions was:

---<snip>---

1. cmake.  You need to have cmake running under CYGWIN.  This is
available
as a standard package now.  You can install it from any CYGWIN
distribution
mirror.  This sure beats building it by hand.

2. opengl header files.  You must move or delete the opengl headers in
/usr/X11R6/include/GL (gl.h, glu.h,.....).  These header files are not
congruent with opengl32.  The -I flag in the makefile forces these
header
files to be found first, if they are present.  If you fail to do this,
you
will get a bunch of undefined library errors when you try to link the
vtk
libraries with an application.  The correct headers are present as part
of
the w32api package.

3. w32api.  You must have a recent version of w32api.  This insures that
your build will correctly reference opengl-1.1.  I suggest installing
the
lastest one from a CYGWIN distribution mirror.

---<snip>---

The full text of the message I grabbed that procedure from can be found
at http://public.kitware.com/pipermail/vtkusers/2003-January/015655.html

Let me know if there's anything else I can help you with, or if you
want me to take a look at the link errors.

Cheers,
-Damion-

On Wednesday, October 22, 2003, at 11:08 AM, Stein,Jeffrey L. wrote:

> Hi all,
>
> I was wondering if anybody has managed to compile the lastest version 
> of OpenGlass cockpit on cygwin.  I did a co install on linux and 
> cygwin and while I found both installs were quite buggy, especially 
> the building of the FTGL libraries finally we managed to get the linux 
> version working.  The cygwin install, however, ran into some issues.  
> Two cpp files would not compile at first but then I managed to fix 
> those issues.
>
> Currently after about 6 hrs of trying I have given up.  I can build 
> the app but it is not linking correctly.  Before I post detailed 
> information I was wondering if anybody has in fact managed to compile 
> under cygwin / gcc lately.
>
> Any help would be appreciated.  I will try to debug the linking errors 
> later today.
>
> -Jeff Stein

---------
Damion Shelton
Carnegie Mellon University, Robotics Institute
A408-o Newell Simon Hall
412.268.3866 (office)
412.818.8829 (cell)
412.268.6436 (fax)
http://www.cs.cmu.edu/~beowulf
---------
I hope that after I die, people will say of me: "That guy sure owed me 
a lot of money."