From: Chris H Subject: Short report from Computer Graphics 91 (UK) Date: Sun, 10 Nov 91 22:51:29 BST Organization: Public access to Usenet in the UK Last week I managed to make it down to the CG91 exhibition, staged at London's Alexandra Palace. Here are a few impressions/comments. This event was disappointing considering that it's supposedly the UK's major graphics show. There was a "virtual world" area, but even this was not very well represented. The two main exhibitors there were Virtual Presence Ltd, who are the UK Distributors for the Sense8 WorldToolKit, and Division Ltd who are currently receiving media attention due to their PROvision system (see BYTE Oct 1991, [p.80IS-53 in UK edition]). It may be worth mentioning Dimension International who were also exhibiting what they called a VR product. What this comes down to is - essentially - a 3D modelling system. They had a reasonable frame-rate on their "Virtual Reality Toolkit" running on a 486 PC with TMS34020-based graphics card, with navigation being provided by a 6-axis "spaceball" and the image displayed on a desktop monitor. They referred to the concept as "Desktop VR", but I can't help thinking that this smacks of bandwagonism... Virtual Presence had a Sense8 system using either VPL eyephones or another headset from the US that looked like a white metal welding mask perched on top of the wearer's head. This latter unit was the one being used for today's demo, but the Logitech tracker being used to track head movement had died, reducing the effect somewhat. The monitor displaying the victim's virtual view showed virtual rooms with window frames, doors and pictures on the walls that had all been chosen from the large collection of predefined textured objects supplied with the WorldToolKit. Even some tropical fish could be seen swimming around nonchalantly in virtual space! The system runs on a 4 Mb 386 or 486 PC with an Intel i750 graphics board (or two boards if eyephones are to be used). On the stand next door, Division had a healthy-sized queue of eager cybernauts waiting to try out their PROvision system. The demonstration system had a "free" 6-axis joystick with 2 top buttons to move forward and backward and a trigger button for grasping virtual objects. The headset was another VPL unit including headphones. I was told that this unit has a field of view of 100 degrees horizontal by 60 degrees vertical. Compared to some other systems, the frame rate of the animated display - which could be seen on the usual monitor - seemed quite slow and jerky. We were told that the image rendering subsystem was implementing radiosity, which could explain the relative slowness of the display, although something was muttered on the demonstration videotape about using pre-calculated radiosity values. The demonstration world available for exploration looked pretty good on the monitors: a corridor with many doors, each of which opened onto a room featuring a variety of objects. One room had a TV and a Teapot (with shading) while another had a giant chessboard floor complete with black and white chesspieces that could be picked up and hurled around (the rate of gravity had been set fairly low, so they took a while to fall to the ground). Donning the eyephones and entering the virtual world revealed the immersed view to be quite different: the heavy use of lenses meant that the image was marred by concentric rings, although though these disappeared somehow after a minute or two. The eyephones were uncomfortable, with a tendency to slip forward and away from the eyes, due to most of the weight being concentrated at the front of the unit. The goggles also seemed rather warm, causing slightly more discomfort to the eyes. Despite the problems I managed to stumble into the Teapot room and inspect the teapot in the middle of the floor by kneeling close by. I then picked it up and walked over to the TV and inserted the Teapot into the side of the TV. This revealed two problems that I presume are common to most VR systems today. Firstly the lack of depth cues meant I was having difficulty finding the television because I was so close to it and it seemed to have disappeared. Secondly, due to the lack of any force-feedback or "bump-detection" I found myself bumbling around inside the space occupied by the television wondering where it had gone. Still confused I managed to find the door and went back into the corridor - teapot still in hand - and entered another room after being greatly baffled by the door due to standing in the doorway intersecting the closed door! My brain gave up at this point and all I could make out in the new room were the light blue walls, apparently missing the sticks-and-balls molecule-like creature bouncing up and down on the floor (this could easily be seen on the monitors, however). Despite the visual problems the sound was helpful, with the doors creaking opening when necessary (sometimes). The teapot also made a sort of quacking noise that become louder as it was approached (!). CG91 also featured a half day tutorial on VR by Charles Grimsdale, Division's Managing Director, as well as a 1.5 day conference chaired by Iann Barron, Divsion's Chairman. Among those billed as being present was Scott Fisher, who I presume we all know (his new company Telepresence Research is using Division's PROvision system, according to Division's press release). I'm sure the other readers of this group would be interested in hearing the comments of any netters who managed to make it to this conference. --------------------------------------------------------------------------- Contact Addresses: DIVISION Ltd Virtual Presence Dimension International Quarry Rd 25 Corsham St Zephyr One Chipping Sodbury LONDON N1 6DR Calleva Park BRISTOL BS17 6AX ALDERMASTON RG7 4QZ UK UK Berks, UK Tel. +44 454 324527 Tel. +44 71 253 9699 Tel. +44 734 810077 Fax. +44 454 323059 Fax. +44 71 490 8968 Fax. +44 734 816940 --------------------------------------------------------------------------- Cheers, Chris