Path: chuka.playstation.co.uk!news From: James Russell Newsgroups: scee.yaroze.freetalk.english Subject: Re: S*ga Dreamc*st Date: Wed, 05 Aug 1998 10:46:18 +0100 Organization: Sony Computer Entertainment Europe Lines: 99 Message-ID: <35C829EA.55EFA3B1@scee.sony.co.uk> References: <3569980E.51FC@saqnet.co.uk> <356A77BD.596@dma-design.com> <356a4d1f.24746116@news.scea.sony.com> <356A8BBD.5DD9@dma-design.com> <35C13E1E.4A99D280@mail.datasys.net> <1dd416x.1cqaclz4vkpc1N@a1-88-110.a1.nl> <6q1g2e$fvf13@chuka.playstation.co.uk> <1dd8b4y.1g33oa41ggvfzhN@[194.151.88.144]> NNTP-Posting-Host: mailgate.scee.sony.co.uk Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Mailer: Mozilla 4.5b1 [en] (Win95; I) X-Accept-Language: en Toby Sargeant wrote: > > b) adding OS development time to hardware development time means that the > time-to-market of a console would (at a guess) be more than doubled. Of > _course_ companies will like the option of choosing off the shelf OS > solutions. It's a pity that the choice has been Microsoft's offering, > though. From what I've heard, MS Windows CE is actually very good. You're forgetting that the _main_ reason why people hate Windows is because it crashes alot. That's because there's millions of lines of code, dating to way back when, some 16 bit, some 32, lots of horrible legacy code. Windows CE was created from scratch, and hence its a very stable system. However, I think Sega are missing the point somewhat. Initially, DC games will use DirectX because it's a standard and easy to port from the PC. But to get the full power out of a console, you have to go low-level. You can't do that anymore on a PC, because you have to write drivers for every video card around, which is why DirectX exists in the first place. But with a standard platform like the DC, programmers will drop to low level to get more speed. There's no question about them doing that eventually, because if you spend that extra time, you can get a much better looking game. Once one company does it, it will be the standard, and everyone else will have to drop to low level to compete. So DirectX will go out the door very quickly. It will only be useful for PC developers wanting to port games. > The problem is not that, it's the fact that on large projects > like Windows 95, the code base has reached critical mass, and the > management has fallen apart, allowing bugs to creep in unnoticed. No, I think we noticed them alright... :O) > > > Having said that, there are a few things that I think could have been better. > Rather than sticking with a hitachi processor, i would have liked to have seen > a mid - high end MIPS, PPC or Alpha processor. The cost of such processors is large in comparison with the rest of the console. Remember that they have to churn out millions of these CPUs _and_ make them cheap enough to put into a home console in the first place. I would want to see a 1Ghz PPC or a 400 PII in PSX2, but nobody wants to pay £600 for a console! :O) > I don't know whether the dual CPU approach of the saturn was a > good idea. Multi threading tends to confuse developers, and introduce all > kinds of subtle bugs. On the other hand, it's a good way to get better > performance for less cost. In the balance, a multi CPU with less powerful > CPUs wins in my book. Programming for multi-CPUs _efficiently_ is at least twice as hard as normal coding. And the complications with the system bus are massive. For instance, there are problems with cache inconsistency between processors. All of these are solvable, of course, but getting 200% power out of 2 CPUs is almost impossible and very difficult to design. From what Colin tells me, most Saturn programmers used the second CPU like a GPU - it just sat there waiting for commands in a queue and processed them whenever they arrived. That's not efficient, but it's easy to program. The other thing about multi-CPUs is that they're only good when you want to do many independent things at once. If you consider that CPU time spent on sound/controller/CD is almost negligible, then the rest of the time is divided into Pre-Scene Creation (like doing all the physics calculations in Gran Turismo), Scene Creation (creating the polygons) and Scene Drawing (drawing them). Since Scene Creation can't be done in parallel with Pre-Scene Creation (with the exception of some games, and assuming you haven't got enough memory for triple buffering), and Scene Drawing is done by the GPU anyway, then multi-CPUs aren't going to help in most cases. > Operating system? QNX. Beats Windows CE hands down. Is stable, _small_, > and it is a realtime OS. AFAIK, Windows CE offers none of those things. Yeah, QNX rocks. However, as I recall, it's only available on Intel CPUs, or at least CPUs with a proper MMU. For speed and cost reasons, I don't think Next-Next-Gen systems will be either Intel or have a MMU. QNX was designed for real-time work, like controlling industrial machines. In comparison, a console OS is really an just an API to the hardware. It only handles interrupts and system calls to hide the effects possible changes in the ROMs and other hardware from developers. I don't consider the PSX libraries to be a true OS, which QNX is. > Memory management. I think it was a minor crime for sony to rip out the MMU > from the Playstation. Why do you need an MMU? You're only running one program. Multi-threading is still possible. Set up of the MMU registers takes extra time and is potentially buggy (ever written a DPMI stub?). It marginally slows down the chip. It requires more silicon, which ups the cost of the chip. In any event, its unlikely that programmers and debuggers would use it much. > Peripherals and connectors. Why not be the first console to be easily > connected to an SVGA monitor? if the PoverVR is rendering at 1600x1200 for > HDTV, then surely it'd be pretty simple to provide SVGA output. The minimum res for the DC is supposed to be 640x480 (although I doubt that is _is_ the minimum). So to view it on an SVGA screen would be great! But I remember seeing Amiga games on the old 1084 monitors (which were slightly better than a TV) and seeing the same game on a PC - graphics actually looked smoother and better on the 1084/TV because, well, TVs are terrible. Everything was too sharp-edged on the PC. But that's just a personal opinion. Cheers, James -- == James_Russell@scee.sony.co.uk +44 (171) 447-1626 == Developer Support Engineer - Sony Computer Entertainment Europe Where there's a will, I want to be in it.