Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270879AbUJVEgQ (ORCPT ); Fri, 22 Oct 2004 00:36:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270857AbUJUTeP (ORCPT ); Thu, 21 Oct 2004 15:34:15 -0400 Received: from mail.scitechsoft.com ([63.195.13.67]:65005 "EHLO mail.scitechsoft.com") by vger.kernel.org with ESMTP id S270845AbUJUTaM (ORCPT ); Thu, 21 Oct 2004 15:30:12 -0400 From: "Kendall Bennett" Organization: SciTech Software, Inc. To: Alan Cox Date: Thu, 21 Oct 2004 12:30:01 -0700 MIME-Version: 1.0 Subject: Re: HARDWARE: Open-Source-Friendly Graphics Cards -- Viable? CC: Linux Kernel Mailing List Message-ID: <4177ABC9.22263.20E9CAFD@localhost> In-reply-to: <1098313825.12374.74.camel@localhost.localdomain> References: <4176E08B.2050706@techsource.com> X-mailer: Pegasus Mail for Windows (4.21c) Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Content-description: Mail message body X-Spam-Flag: NO Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1860 Lines: 43 Alan Cox wrote: > I've actually always wondered what a hybrid video device would > look like for 3D. Doing the alpha blend and very basic operations > only in the hardware that are expensive in software - alpha and > perhaps some of the texture scaling, but walking textures in > software, doing shaders in software and so on. Well that is what most of the early 3D cards started out as. A lot of the early SGI boxes that has '3D' were not full 3D rendering engines but span based rendering engines. Not only was setup done in software, but so was the walking of the triangle sides and the only thing passed to the hardware was commands to render spans (flat, smooth or textured). You could build any kind of complex renderer on top of this and in those days it was SGI GL (pre OpenGL) that was the rendering API. The systems were also reasonably fast for the day too. I think the original 3DLabs GLINT SX chipset also did span rendering and support textured spans. The biggest problem is that the overhead required by the CPU to process anything close to the volume of triangles per second that high end cards can handle today is overwhelming. Even a 4Ghz P4 probably couldn't keep up trying to match the transform, lighting and span traversal to match even a basic Radeon 9000 card IMHO. And then you've got no CPU cycles left for anything else such as sound and game physics ;-) Regards, --- Kendall Bennett Chief Executive Officer SciTech Software, Inc. Phone: (530) 894 8400 http://www.scitechsoft.com ~ SciTech SNAP - The future of device driver technology! ~ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/