From: broehl@sunee.waterloo.edu (Bernie Roehl) Subject: Re: TECH: My standard is better than your standard. Date: Thu, 6 Aug 1992 14:03:24 GMT Message-ID: Organization: University of Waterloo In article <1992Aug5.055021.1606@u.washington.edu> Jeremy Lee writes: >Let me present my idea, and to do it I will reason by analogy. Okay. (By the way, did you ever post your paper? If you did, I missed it; I'd appreciate getting a copy by email). >[idea of "circle of friends" omitted to keep this article short] It's a good idea, but how do you implement it? In other words, how do I know who I want to to talk to, without first talking to *everyone* to find out enough about them to make that decision? (To save some newsgroup bandwidth: if your answer is "talk to one object and ask it who *it* talks to, and so on", then I would argue that you'll wind up talking to a vast number of objects that you don't need to. Worst case is you wind up having to talk to the entire universe). >>Therefore "objects I can touch" is a subset of "objects I can see". > >Can you touch the back of your head? Can you feel inside an >almost-closed box? We have to clearly define the "objects I can see" to include such cases. >What if I "dislocate" my hand. I'd say "see the doctor about it", but that's only because I'm not sure what you mean. >Or better yet, how do I simulate a cold breeze. The breeze can be modelled in several ways, but the simplest may be an object that can "see" everything it goes past and sends messages to them along the way saying "I'm a breeze and here's my force vector and air temperature". (Wind chill is computed by the receiving object). >[Regarding the issue of 128-bit coordinates] >And so every time I change worlds I have to recompile my objects? No, of course not. Why would you? >I have a 32bit RISC computer that does 4 mips. >The company that made it (Acorn) was a very forward thinking one Are they still around? If not, is anybody making reasonably-priced machines of equivalent horsepower? >I also think VR will only take off on >massivley parallel machines, and that it it still 5-10 years away. I disagree completely. I think we're looking at a timeframe of less than a year. There are already systems out there (e.g. Virtuality) that proclaim themselves to be VR, and by most people's definitions they certainly are. What we're discussing is how to define a standard protocol for allowing virtual worlds to be shared. Saying "Well, we don't have to worry about it for another decade" is (in my opinion) short-sighted; I suspect that if we follow that route, and design a protocol that can't be implemented for ten years, then the protocol we come up with will *never* be implemented at all. Instead, we'll wind up stuck with either a variety of incompatable proprietary protocols whose only virtue is that they run on existing hardware. >What needs to be done is for >every person to sit down and write a largish document describing how >they would like VR to be done. I think it's still far too early for this. I know that my own views are changing daily, shaped by this discussion; I couldn't put together a largish document at this point, because I think there are still far too many unanswered questions (and my own answers are very much in a state of flux). I've also found that as soon as people invest time in writing a "largish document", they become so attached to the ideas contained within it (because of the amount of time and effort they've invested in writing it) that they become inflexible and reluctant to accept approaches that differ from their own. If everyone were to write a document, we'd have a discussion in which everyone works to make their document the standard (or to make the standard as close to their ideas as possible); I suspect this would be counter- productive. I much prefer the free-wheeling kind of discussion we're having now. >Then submit them to the newsgroup and >have some proper discussion about a document that we all have sitting in >front of us, so that we can make references to "paragraph 3 on page 14" >and have some intelligent conversation. I see your point on this, and I think it's a useful way of reviewing and improving whatever standard we come up with; I just think it's too soon in the discussion process for everyone to put their ideas on paper. I'd also rather see us work toward one (or possibly two) specifications, rather than have everyone submit their own and then argue its merits. >I also suggest that we start getting together on IRC (Those who have >access). I think this is a great idea, and I'd like to meet with you on IRC and discuss things more interactively (we'd have to schedule a time to meet). However, I suspect the number of people in this discussion who have IRC access is very, very small. Again, it's the same problem as setting the hardware requirements for a VR station too high; it's great for the people who can do it, but there are so few it may not be worthwhile. As to IRC... how about this. Everyone reading this who has IRC access and would like to participate in an interactive discussion, speak up now. Uh oh... I sense an impending flurry of "What's IRC?" messages, followed by the inevitable "How do I get it?"; "Okay, I've got it, how do I compile it?"; "Say this is neat but my terminal's doing *this* and I can't get it to stop" messages. Since Jeremy brought it up, I'll let him answer them. :-) In any case, I'll be away on holidays next week (Aug 9 noon Eastern Standard Time to Aug 16 6 pm EST). -- Bernie Roehl, University of Waterloo Electrical Engineering Dept Mail: broehl@sunee.waterloo.edu OR broehl@sunee.UWaterloo.ca BangPath: uunet!watmath!sunee!broehl Voice: (519) 885-1211 x 2607 [work]