From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Stabellini Subject: Re: opengl=1? Date: Thu, 11 Dec 2008 11:11:41 +0000 Message-ID: <4940F56D.30202@eu.citrix.com> References: <4940EC5E.5000401@eu.citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Jun Koi Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org Jun Koi wrote: > On Thu, Dec 11, 2008 at 7:33 PM, Stefano Stabellini > wrote: >> Jun Koi wrote: >> >>> Hi, >>> >>> I found that we have an option named opengl. What is that for? So if I >>> put "opengl=1" in my VM configuration file, what advantage my VM will >>> get?? >>> >> opengl=1 is the default and makes qemu render the guest framebuffer >> using opengl. > > OK, so the patch you posted on QEMU mailing list is to enable this > function on QEMU. Yes. >> Otherwise if you set opengl=0 qemu will use the sdl library. >> opengl=1 makes sense if you don't use vnc > > So this means "opengl=1" (default) and "vnc=0" will give a better > performance than "vnc=1, sdl=0", right? Just to be clear opengl is used only together with sdl: sdl is still needed to create the window. So the three possibilities are: /* window on the host screen, opengl acceleration */ sdl=1 opengl=1 vnc=0 /* window on the host screen, no opengl acceleration */ sdl=1 opengl=0 vnc=0 /* no window on the host screen just a vnc server */ sdl=0 (opengl does not matter) vnc=0 >> and you have good drivers for >> your graphic card in dom0. > > I am using Ubuntu 8.10 with chipset Intel 945GM, so certainly I have > "good driver", right? > If you are using the intel driver (intel, i815, i915, etc.) in xorg, yes; if you are using the vesa driver, no. If you are using opengl=1 and the vesa driver in xorg, you'll notice because it is really slow.