X-Recipient: archive-cygwin AT delorie DOT com
X-SWARE-Spam-Status: No, hits=-1.8 required=5.0	tests=AWL,BAYES_40,RCVD_IN_DNSWL_LOW
X-Spam-Check-By: sourceware.org
Message-ID: <4C863765.40104@dronecode.org.uk>
Date: Tue, 07 Sep 2010 14:00:21 +0100
From: Jon TURNEY <jon DOT turney AT dronecode DOT org DOT uk>
Reply-To: cygwin AT cygwin DOT com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.9) Gecko/20100825 Thunderbird/3.1.3
MIME-Version: 1.0
To: cygwin AT cygwin DOT com
CC: daviddoria AT gmail DOT com
Subject: Re: OpenGL linking problems
References: <BLU149-W61362F960F0FAABEA6CE9A938E0 AT phx DOT gbl> <AANLkTik5E=zE3NbxNFNcSVSU2QFp3mTqFEOeZfGdCecw AT mail DOT gmail DOT com>
In-Reply-To: <AANLkTik5E=zE3NbxNFNcSVSU2QFp3mTqFEOeZfGdCecw@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 8bit
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Id: <cygwin.cygwin.com>
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com

On 04/09/2010 17:29, André Bleau wrote:
On 05/09/2010 00:16, David Doria wrote:
>> Well, we need more info to help us help you. What kind of application are you trying to build? X11 or native? There are 2 ways to build OpenGL-related programs:
>>
>> 1- Using native OpenGL, with driver supported hardware acceleration. For that, you need some way to
>> get a graphic device context. One portable way to do that is to use the GLUT library, provided by
>> the opengl package that I maintain. Look at the doc in /usr/share/doc/opengl-1.1.0 to learn how to
>> do that.
>>
>> The OpenGL implementation in that case is provided by Window's opengl32.dll. Cygwin's w32api package
>> provides the headers and link library for that version of OpenGL.
>>
>> LD_LIBRARY_PATH has no effect if you go that way.
>>
>> 2- Using X11, which provides an opengl implementation. At one point, there was support for hardware
>> acceleration; then, it went away; I don't know if it came back or if it is coming back "soon". I will let the maintainer of the libGL* packages answer questions you may have about it. You would better send them to cygwin-xfree at cygwin dot com .

[1] discusses the differences between using OpenGL with WGL or with GLX.

AIGLX should be back "soon", indeed :-)

I've had precisely zero feedback on the test releases I've done, so I assume 
nobody is very interested in this feature, and it's very 
2-steps-forward-1-step-back keeping the necessary patches to mesa libGL 
working, but hopefully it will make an appearance in Xserver 1.9

[1] http://x.cygwin.com/docs/faq/cygwin-x-faq.html#q-opengl-link-problems

>> - André Bleau, Cygwin's opengl package maintainer.
>
> Hi André,
>
> I think I'm trying to build an X11 application - I'm trying to use a
> library called VTK (http://www.vtk.org/). I don't believe it uses
> glut, and I do see a bunch of X11 options in the CMake files. Even if
> there is no support for hardware acceleration with this method, it
> should still build, right?
>
> I do have C:\Windows\System32\opengl32.dll . I should also have the
> w32api package because I installed all of the cygwin packages.
>
> Any other thoughts of things that would causes these linking errors?

Since you don't give the link line which is causing the problem, I'd tend to 
assume the problem is [2]

[2] http://cygwin.com/faq/faq-nochunks.html#faq.programming.linker

--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple