From owner-freebsd-current Thu Nov 4 10: 3:17 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 6ABFD151C2 for ; Thu, 4 Nov 1999 10:02:59 -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 KAA46924; Thu, 4 Nov 1999 10:01:37 -0800 (PST) (envelope-from hasty@rah.star-gate.com) Message-Id: <199911041801.KAA46924@rah.star-gate.com> X-Mailer: exmh version 2.0.2 2/24/98 To: Soren Schmidt Cc: yokota@zodiac.mech.utsunomiya-u.ac.jp (Kazutaka YOKOTA), current@FreeBSD.ORG Subject: Re: vga driver and signal In-reply-to: Your message of "Thu, 04 Nov 1999 14:13:23 +0100." <199911041313.OAA93012@freebsd.dk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Thu, 04 Nov 1999 10:01:37 -0800 From: Amancio Hasty Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > It seems Kazutaka YOKOTA wrote: > > > > AFAIK, not all video cards generate the vertical retrace interrupt. > > Even worse, some BIOSes have a configuration option which instract the > > BIOS NOT to assign an IRQ to the PCI video card. > > > > I fully agree that the vertical retrace interrupt will be of great > > value, but I wonder if it is really worth the trouble, because it might > > be available in only few cards and systems at the end of the day... > > > > Well, I may be wrong :-) > > Well, sortof :) > > The delay caused by the system to process the interrupt and deliver > the signal etc is unpredictable (well sortof) and is almost certainly > too long so the window of opportunity will be missed ... > > This has been discussed to death many times in the past for the > mouse pointer updates etc etc... > Let me ask a different question: How does Microsoft's DirectX handle delivery of vertical retrace interrupt? -- 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