From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59318) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VePus-0002VX-EA for qemu-devel@nongnu.org; Thu, 07 Nov 2013 08:46:40 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VePum-0000AP-Ab for qemu-devel@nongnu.org; Thu, 07 Nov 2013 08:46:34 -0500 Received: from mx1.redhat.com ([209.132.183.28]:54815) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VePum-00009i-0P for qemu-devel@nongnu.org; Thu, 07 Nov 2013 08:46:28 -0500 Message-ID: <1383831984.3511.78.camel@nilsson.home.kraxel.org> From: Gerd Hoffmann Date: Thu, 07 Nov 2013 14:46:24 +0100 In-Reply-To: <527A62BD.2010401@spineless.org> References: <52795824.3090105@citrix.com> <1383735351.1739.57.camel@nilsson.home.kraxel.org> <527A62BD.2010401@spineless.org> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] Multi-head support RFC List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: John Baboval Cc: qemu-devel@nongnu.org Hi, > As far as the EDID is concerned, there can only be one EDID for a > display+hw pair, or the guest won't know what to do. In my use-case, I > simply pass real EDIDs through, and create a full-screen window for each > real monitor. Ok, makes sense. > If you wanted to have two UIs displaying the same > DisplaySurface, the EDID would have to come from one of them, and the > other would have to clip, or scale. Yes. > > Why not? That is exactly my plan. Just have the virtual graphic card > > call graphic_console_init() multiple times, once for each display > > connector it has. > > > > Do you see fundamental issues with that approach? > Currently only one QemuConsole is active at a time, so that would have > to change.... That isn't mandatory any more. It is still the default behavior of a DisplayChangeListener to follow the active_console, for compatibility reasons. SDL and VNC still behave that way. You can explicitly bind a DisplayChangeListener to a QemuConsole though, by setting DisplayChangeListener->con before calling register_displaychangelistener(). gtk binds to QemuConsole #0. spice creates a display channel per (graphical) console. Each display channel has a DisplayChangeListener instance, and each DisplayChangeListener is linked to a different QemuConsole. For your UI you probably want follow the spice model. Have a DisplayChangeListener for each physical monitor of the host, have a fixed QemuConsole bound to each DisplayChangeListener. DisplayChangeListeners can come and go at runtime just fine, so you should be able to create/destroy them on monitor plug/unplug events on the host. cheers, Gerd