Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm List-Subscribe: List-Archive: List-Post: List-Help: , Sender: cygwin-owner AT cygwin DOT com Mail-Followup-To: cygwin AT cygwin DOT com Delivered-To: mailing list cygwin AT cygwin DOT com Message-Id: <5.2.0.9.0.20030708160702.0287c8a0@irispavp.igb.umontreal.ca> X-Sender: bleau3 AT irispavp DOT igb DOT umontreal DOT ca (Unverified) Date: Tue, 08 Jul 2003 16:25:32 -0400 To: cygwin AT cygwin DOT com From: Andre Bleau Subject: Re: Performance problem Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1"; format=flowed Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by delorie.com id h68KMRJ00530 If I am interpreting the output below correctly, you are developing an OpenGL program under X11; that's the main reason it is so slow. OpenGL under X11 renders everything in software, without any hardware acceleration, so it's rendering is orders of magnitude slower. It is true that Cygwin's I/O and memory management are somewhat slower than under Linux, but that's peanuts compared to the OpenGL penalty. If you want a fast program, you will have to use Window's native OpenGL implementation, which renders through hardware accelerators. That's what the OpenGL package for Cygwin provides. Unfortunately, to use Window's native OpenGL implementation, you will have to rewrite completely such parts of your program as window management and user interface. Last point (before you ask): the OpenGL implementation under X11 cannot be easily modified to use hardware acceleration, and I doubt it can be modified at all to do so. To know why, please search the archives for this list. Vladimir Baltchev wrote: >Hi there, >We are about to port Unix - Irix and Linux applications to Windows using >Cygwin. However the Cygwin version is very slow compared to Linux, even I >compiled with the optimize option -O2. It is a Windows 2000, the program >is a segmentation editor using Qt, OpenGl and some image processing. >What is the reason? Is it OpenGL on cygwin, or both? >Here is the library dependency list: >segeditorMax.exe >C:\cygwin\usr\X11R6\bin\libGL.dll >C:\cygwin\usr\X11R6\bin\libX11.dll >C:\cygwin\bin\cygwin1.dll >C:\winnt\System32\KERNEL32.dll >C:\winnt\System32\NTDLL.DLL >C:\cygwin\usr\X11R6\bin\libXext.dll >C:\cygwin\usr\X11R6\bin\libGLU.dll >c:\qt-cygwin\qt-3\bin\cygqt-mt-3.dll >C:\cygwin\usr\X11R6\bin\libICE.dll >C:\cygwin\usr\X11R6\bin\libSM.dll >C:\cygwin\usr\X11R6\bin\libXrender.dll >C:\cygwin\bin\cygpng12.dll >C:\cygwin\bin\cygz.dll >C:\winnt\System32\ADVAPI32.DLL >C:\winnt\System32\RPCRT4.DLL >c:\Vlad\build\Dev\lib\libOip.dll >C:\winnt\System32\GDI32.dll >C:\winnt\System32\USER32.DLL André Bleau, Cygwin's OpenGL package maintainer. email: bleau at igb dot umontreal dot ca (Fight SPAM: encode your email-address) Please address all questions and problem reports about Cygwin's OpenGL package to cygwin AT cygwin DOT com . -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Problem reports: http://cygwin.com/problems.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/