From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rafi Rubin Subject: Re: [PATCH] hid-ntrig.c Multitouch cleanup and fix Date: Tue, 09 Mar 2010 17:32:00 -0500 Message-ID: <4B96CC60.8030608@seas.upenn.edu> References: <4B75E14A.2050602@seas.upenn.edu> <1266027185-5311-1-git-send-email-rafi@seas.upenn.edu> <4B760D60.6020907@seas.upenn.edu> <4B96B740.7020208@euromail.se> <4B96BAF1.5070209@seas.upenn.edu> <5423752A-3AE0-4848-9149-B0C01B0BCA39@enac.fr> <20100309222731.GA29517@core.coreip.homeip.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from LION.seas.upenn.edu ([158.130.12.194]:46735 "EHLO lion.seas.upenn.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755363Ab0CIWcL (ORCPT ); Tue, 9 Mar 2010 17:32:11 -0500 In-Reply-To: <20100309222731.GA29517@core.coreip.homeip.net> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Dmitry Torokhov Cc: =?ISO-8859-1?Q?St=E9phane_Chatty?= , Jiri Kosina , Henrik Rydberg , linux-input@vger.kernel.org >> With this regard, I am a big fan of the idea of having hierarchical >> devices, just like with have hierarchical file systems. Each finger >> on the dual-touch panel would be a device, child of the panel >> device. Each would be equivalent to a mouse, and voila, the symmetry >> is restored. Conceptually, saying (panel/finger1, any event) or >> (panel, finger1 events) are equivalent; but in the first case the >> routing is done by the OS and in the second case it has to be done >> by the app, which breaks reusability. There are other interesting >> perspectives, but I don't want to get carried away too much. > > Theoretically it is nice but it practice the cases are differemt: with > mice you are dealing with 2 separate devices whereas with touchscreen > there is one and it is mater of interpretation whether 2 touches should > be taken as independent events or a complex gestures. I see your point, reporting the position on separate axes (ABS_X and ABS_MT_X) isn't as problematic as seeing TOUCH turn on twice.