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=-1.9 required=5.0 tests=BAYES_00 autolearn=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,c3768896d3e82ec X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news4.google.com!news.glorb.com!feeder.enertel.nl!nntpfeed-01.ops.asmr-01.energis-idc.net!216.196.110.149.MISMATCH!border2.nntp.ams.giganews.com!nntp.giganews.com!news-in.ntli.net!newsrout1-win.ntli.net!ntli.net!newspeer1-win.ntli.net!newsfe4-gui.ntli.net.POSTED!53ab2750!not-for-mail From: "Dr. Adrian Wrigley" Subject: Re: Game Programming / Graphics User-Agent: Pan/0.14.2 (This is not a psychotic episode. It's a cleansing moment of clarity.) Message-Id: Newsgroups: comp.lang.ada References: <1112471680.276284.42140@o13g2000cwo.googlegroups.com> <1112540503.324258.129700@z14g2000cwz.googlegroups.com> <425d9a2e$0$12427$626a14ce@news.free.fr> <3Xgbe.582$Gd7.398@newssvr21.news.prodigy.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Date: Tue, 26 Apr 2005 17:50:28 GMT NNTP-Posting-Host: 80.4.127.115 X-Complaints-To: http://www.ntlworld.com/netreport X-Trace: newsfe4-gui.ntli.net 1114537828 80.4.127.115 (Tue, 26 Apr 2005 18:50:28 BST) NNTP-Posting-Date: Tue, 26 Apr 2005 18:50:28 BST Organization: ntl Cablemodem News Service Xref: g2news1.google.com comp.lang.ada:10725 Date: 2005-04-26T17:50:28+00:00 List-Id: On Tue, 26 Apr 2005 01:37:03 +0000, adaworks wrote: ... > Also, I think some of the work being done by Dr. Wrigley is appropriate > to this domain. In particular, his work in high-performance rendering > with Ada might be worth learning, if he is willing to share it with those > who need to see it. I saw my name mentioned... The work I was doing was at Advanced Rendering technology, now ARTVPS (See: http://www.artvps.com/ ). I haven't worked for that business for several years now. In summary: the problem (realistic image generation using numerical models of light distribution) seems well suited to OO techniques, but we'd had difficulty (in the mid '90s) getting the right kind of flexibility, coupled with memory and run-time efficiency. We implemented the first products mainly in C and assembly language, with chip design in VHDL (Ada's close cousin!). This had the advantage of familiarity (to management and key staff), and the tools were robust and mature. C++ was an obvious (but contentious) alternative. But taking on a big C++ project was risky because of lack of team experience with projects of this size, as well as uncertainty over meeting performance and interface constraints. A second generation of software was developed, factoring in experience from the first generation. The numerical core (infinite dimensional integration engine(!)) was factored out, and the module boundaries strengthened. The existing low-level C, Assembly code was retained. The new, high-level code was in Ada. The strengths of Ada really shone in this project, particularly the robust encapsulation, the (contract-based) genericity, and the concurrency. But staff familiarity was still an issue, as was performance. I had to leave the company when a key investor rejected (essential) changes to the business model, and it collapsed just over two years later :( The investors received nil. The business was bought out, and is still going today, but the second generation software was abandoned when I left (in late 1999). >From this experience, I became convinced that Ada 95 gives a very strong technical approach to development of complex systems in numerical computing (an ideal replacement for the Fortrans). But projects face significant risks in staff acceptance, training etc. Often people want to work in languages which further their careers, ie *not* Ada! At the moment, I am building computationally intensive statistical models of the US stock markets, and have built a fully automated, real-time stock trading system. The low defect density and code readability is invaluable, even for a one-person project such as this. Hope this helps! -- Dr. Adrian Wrigley, Cambridge, UK.