From owner-freebsd-current Wed Nov 3 14:24: 0 1999 Delivered-To: freebsd-current@freebsd.org Received: from rah.star-gate.com (216-200-29-190.snj0.flashcom.net [216.200.29.194]) by hub.freebsd.org (Postfix) with ESMTP id C94ED150E6 for ; Wed, 3 Nov 1999 14:23:53 -0800 (PST) (envelope-from hasty@rah.star-gate.com) Received: from rah.star-gate.com (localhost.star-gate.com [127.0.0.1]) by rah.star-gate.com (8.9.3/8.8.8) with ESMTP id OAA39942 for ; Wed, 3 Nov 1999 14:23:15 -0800 (PST) (envelope-from hasty@rah.star-gate.com) Message-Id: <199911032223.OAA39942@rah.star-gate.com> X-Mailer: exmh version 2.0.2 2/24/98 To: current@FreeBSD.ORG Subject: vga driver and signal Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Wed, 03 Nov 1999 14:23:15 -0800 From: Amancio Hasty Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Say is there anyone that can add signal delivery to the /sys/dev/fb/vga.c? (For now any quick hack to the driver for delivering the signal will do ) The context is from a posting to the xfree86 mailing list: keithp@suse.com said: > You need to fit one event in per retrace. If you knew > the phase of the sampling clock with respect to the retrace > you could do that by skipping one sample then two then one, etc... > But we don't know the phase and if you do that with > arbitrary phase you end up sending two events in one retrace > and then skipping the next and it looks worse. > If we had a signal delivered at vertical retrace time, we could easily > sync the mouse rate with the video rate -- run the mouse events > through a simple filter and estimate mouse position at the vertical > retrace interval using some forward estimation. > Additionally, the vertical retrace signal could be used for the double > buffering extension to avoid tearing, and for the sync extension which > kinda wants this. And for many video cards which can't update > colormaps or cursor positions at other times without visible artifacts > on the screen. > It would take some kernel work though; the results might well be worth > the effort. > -keith I am too busy nowdays working :( Have Fun Guys! -- Amancio Hasty hasty@rah.star-gate.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message