220 32764 <3f730e70-23a7-2654-486f-af9151cbc957@gmail.com> article Path: news.gmane.org!.POSTED!not-for-mail From: Matthew Woehlke Newsgroups: gmane.comp.lang.c++.isocpp.proposals Subject: Re: Why do we include a Matrix and Vector class into the proposed 2D Graphics Library? Date: Tue, 13 Jun 2017 16:48:26 -0400 Lines: 30 Approved: news@gmane.org Message-ID: <3f730e70-23a7-2654-486f-af9151cbc957@gmail.com> References: <7e3ee19d-f758-4d38-a015-0c474424073d@isocpp.org> <4f11ca6c-d24c-4c56-8297-bdbbbc45a517@isocpp.org> <18d7bd61-8c41-d0e5-9691-6defb0dacb21@gmail.com> <293bb74a-165d-46b2-a567-0561ee0a9dbd@isocpp.org> Reply-To: std-proposals@isocpp.org NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" X-Trace: blaine.gmane.org 1497386916 27069 195.159.176.226 (13 Jun 2017 20:48:36 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 13 Jun 2017 20:48:36 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.0 Cc: jakob.riedle@gmail.com To: std-proposals@isocpp.org, Chet Original-X-From: std-proposals+bncBC37LBFWUIFBBI47QHFAKGQECFMHNXI@isocpp.org Tue Jun 13 22:48:32 2017 Return-path: Envelope-to: gclcip-std-proposals@m.gmane.org Original-Received: from mail-qt0-f198.google.com ([209.85.216.198]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dKsjn-0006m6-Nl for gclcip-std-proposals@m.gmane.org; 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[66.194.253.20]) by smtp.googlemail.com with ESMTPSA id t193sm6264256ita.24.2017.06.13.13.48.33 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 13 Jun 2017 13:48:34 -0700 (PDT) Original-Newsgroups: gmane.comp.lang.c++.isocpp.proposals In-Reply-To: <293bb74a-165d-46b2-a567-0561ee0a9dbd@isocpp.org> Content-Language: en-US X-Original-Sender: mwoehlke.floss@gmail.com X-Original-Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com; spf=pass (google.com: domain of mwoehlke.floss@gmail.com designates 2607:f8b0:4001:c0b::243 as permitted sender) smtp.mailfrom=mwoehlke.floss@gmail.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=gmail.com Precedence: list Mailing-list: list std-proposals@isocpp.org; contact std-proposals+owners@isocpp.org List-ID: X-Google-Group-Id: 399137483710 List-Post: , List-Help: , List-Archive: List-Subscribe: , List-Unsubscribe: , Xref: news.gmane.org gmane.comp.lang.c++.isocpp.proposals:32764 Archived-At: On 2017-06-13 15:19, Chet wrote: > Existing practice is inconsistent with the ordering. > > Example: Northing and Easting, although sometimes reversed, world > coordinates are often presented with Northing first. Northing being Y and > Easting being X, however this can differ in different geographic regions. Geodesy is *weird* :-). (And I don't just mean the habit of ordering point values "backwards".) On a note of amusing coincidence, I committed https://github.com/Kitware/kwiver/commit/5680fd16db4349e37f1f94896e385b2ab8a22b32 only 19 days ago. (Executive summary: kwiver::vital::geo_point specifies Easting, Northing storage.) The previous geo-point type I wrote was not an array, and had members "northing" and "easting". (Granted, they were in that order.) IMO, as soon as you have something that can be accessed like an array, you're going to have users expecting that `p[0]` is the "x" value. -- Matthew -- You received this message because you are subscribed to the Google Groups "ISO C++ Standard - Future Proposals" group. To unsubscribe from this group and stop receiving emails from it, send an email to std-proposals+unsubscribe@isocpp.org. 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