From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: * X-Spam-Status: No, score=1.6 required=5.0 tests=BAYES_40,CTE_8BIT_MISMATCH, FREEMAIL_FROM,HELO_NO_DOMAIN,MAILING_LIST_MULTI, PP_MIME_FAKE_ASCII_TEXT,RDNS_NONE,SPOOFED_FREEMAIL_NO_RDNS autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII X-Google-Thread: 103376,7af3eb61e15f9a0b X-Google-Attributes: gid103376,public X-Google-ArrivalTime: 2001-11-17 06:19:31 PST Path: archiver1.google.com!news1.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!fr.usenet-edu.net!usenet-edu.net!enst!enst.fr!not-for-mail From: "Gautier Write-only-address" Newsgroups: comp.lang.ada Subject: Re: pointer movement? Date: Sat, 17 Nov 2001 14:18:17 +0000 Organization: ENST, France Sender: comp.lang.ada-admin@ada.eu.org Message-ID: Reply-To: comp.lang.ada@ada.eu.org NNTP-Posting-Host: marvin.enst.fr Mime-Version: 1.0 Content-Type: text/plain; format=flowed X-Trace: avanie.enst.fr 1006006769 59118 137.194.161.2 (17 Nov 2001 14:19:29 GMT) X-Complaints-To: usenet@enst.fr NNTP-Posting-Date: Sat, 17 Nov 2001 14:19:29 +0000 (UTC) To: comp.lang.ada@ada.eu.org Return-Path: X-Originating-IP: [217.162.132.78] X-OriginalArrivalTime: 17 Nov 2001 14:18:18.0413 (UTC) FILETIME=[B43FF5D0:01C16F72] Errors-To: comp.lang.ada-admin@ada.eu.org X-BeenThere: comp.lang.ada@ada.eu.org X-Mailman-Version: 2.0.6 Precedence: bulk List-Help: List-Post: List-Subscribe: , List-Id: comp.lang.ada mail<->news gateway List-Unsubscribe: , List-Archive: Errors-To: comp.lang.ada-admin@ada.eu.org X-BeenThere: comp.lang.ada@ada.eu.org Xref: archiver1.google.com comp.lang.ada:16643 Date: 2001-11-17T14:18:17+00:00 >From: "Andrzej Rybczynski" >I want to do some transformations of large bitmap (dynamically >allocated). With c/c++ I used to do this by moving pointer from >pixel to pixel over all array. What is most important - it has to be >extremely fast. How should I do this in Ada? Can I use package >System.Storage_Elements for this purpose ? Depending on the compiler, the code for moving an index in an array like "bitmap: array(0..xmax*xmax-1) of pixel_type" might deliver the same speed as moving the equivalent pointer - this, when optimisation is on and checks are off... ______________________________________________________ Gautier -- http://www.mysunrise.ch/users/gdm/e3d.htm NB: Do not answer to sender address, visit the Web site! Ne r�pondez pas � l'exp�diteur, visitez le site ouaibe! _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp