User Performance in Relation to 3D Input Device Design - CiteSeerX

User Performance in Relation to 3D Input Device Design ShuminZhai IBM Almaden Research Center

Abstract Based mainly on a series of studies the author conducted at the University of Toronto, this article reviews the usability of various six degrees of freedom (6 DOF) input devices for 3D user interfaces. The following issues are covered in the article: the multiple aspects of input device usability (performance measures), mouse based 6 DOF interaction, mouse modifications for 3D interfaces, free-moving isotonic 6 DOF devices, desktop isometric and elastic 6 DOF devices, armature-based 6 DOF devices, position vs. rate control and the form factors of 6 DOF control handle.These issues are treated at an introductory and practical level, with pointers to more technical and theoretical references.

Introduction As three-dimensional (3D) graphics moves to the core of many mainstream c o m p u t e r systems and applications, the search for usable input devices for 3D object manipulation becomes both an academic inquiry and a practical concern. In the case of the 2D graphical user interface (GUI), the computer mouse established itself very early and quickly replaced the light pen as the de facto standard input device (see [13] for a review of mouse history). In the case of 3D interfaces, however, there is still not an obvious winner suitable for all applications. Primarily based on the author's own research, this article offers a few perspectives on the usability of various input devices for 3D interface. This article does not intend to present a comprehensive literature review or a series of experimental studies in a methodical manner. Rather, it intends to be introductory and practical. Interested readers are encouraged to examine more technical details in the papers referenced. In o r d e r to be able to manipulate 3D objects, one generally needs at least six degrees of freedom (6 DOF), three for X,Y and Z translation and three for 3D rotation. The difficulty in establishing a standard 6 DOF device is twofold. First, there are engineering challenges in terms of sensor technologies, manufacturing cost and designer's creativity. It is highly likely that the most elegant 6 DOF device has still not been designed. Second, and perhaps more importantly, even if we could easily make any device we like to, there is only a very limited knowledge about what properties a good 6 DOF controller should have. Given the long history of human factors study on input control devices, dating back to World War II [I I],"One would expect the relation50

November 1998 Computer Graphics

ship of the hand to the controlled element, being at the one time both an input and output, to be a fruitful area for research" but the reality is that little is well understood [3]. Burrows pointed out that the reluctance to conduct research in this area is understandable in view of the immensity of the possible interactions among the many dimensions of control feel. This is not to say that there isn't any intellectual guidance to 6 DOF input device design. Motivated by the manual control problems in vehicles, air crafts and other dynamic complex machines, the topic of "manual control and tracking" has been extensively studied (see [14] for a summary). However, system dynamics resulted from mass, spring, viscosity, transmission delay, etc. in these systems soon dominated the area.The study of input control device properties (e.g. [ I ] ) quickly gave way to mathematical control theory modeling of manmachine systems. The more general body of knowledge on human m o t o r control and learning (see [I 6] for example), while offering many insights, rarely provides direct design guidelines. One recent review of the scattered literature related to input device design is provided in [21 ].

Performance Measures of 6 DOF Input Devices There are many choices in designing o r selecting a 6 DOF input device.The choice on every design dimension may have implications on users' performance. Aside from application specific requirements, there are at least six aspects to the usability of a 6 DOF input device, namely: • Speed • Accuracy • Easeof learning • Fatigue • Coordination • Device persistence and acquisition The first four aspects are common to all input devices and their meanings are obvious. The fifth aspect, coordination, is unique to multiple degrees of freedom input control. There are many ways of measuring the degree of coordination. One effective way of quantifying it is based on the ratio between the length of actual trajectory and that of the most efficient trajectory in the coordination spaces, including translation space, rotation space and the 2D space between translation and rotation [23]. By such a measure, in order to produce the most coordinated path, one has to simultaneously move all degrees of freedom involved at the same pace towards their respective goal states. The sixth aspect of input device usability is

the ease of device acquisition. This is often an overlooked aspect of input device usability. Although a mouse is less dexterous than a pen-like input device (a stylus), the fact that a mouse can be more easily acquired is one important reason that made it the dominant 2 DOF input device. Many factors, such as the distance to the computer keyboard home row (ASDFGHJKL keys), contribute to the ease of device acquisition. One of them is the device location persistence when released. With a mouse or a trackball, when released by the hand (in order to type something, for example) it stays in position. This is not true with a stylus. W i t h these measures in mind, the remainder of the paper examines a few common classes of 6 DOF input devices.

Mouse Based 6 D O F

Input Mouse Mapping The simplest implementation of 6 DOF manipulation can be six graphical sliders on the computer screen. Each can be dragged with a standard 2 DOF input device, such as a mouse. There are two fundamental usability problems to such a 6 DOF interaction technique. First, people cannot mentally decompose orientation into separate rotational axes [12]. Second, since one has to time-multiplex between the separate degrees of freedom, it is not possible to form a coordinated movement in the 6 DOF space. Researchers soon moved away from the six slider implementation to more complex mapping techniques. One such technique is enclosing the manipulated 3D object with a virtual sphere [4]. Some of these techniques in fact have been widely used in 3D graphics software such as VRML browsers and CAD packages. A recent study [7] found the mouse mapping techniques still inferior to integrated 6 DOF devices.

Mice Modified for 3D Operation Efforts have been made to add more physical degrees of freedom to the mouse for 3D interfaces. One example is the roller mouse that had an additional degree of freedom by means of a roller ([18], see Figure I).A user could rotate the roller to move a 3D cursor in the depth dimension (translation only). Another example is the rockin' mouse with two additional degrees of freedom by means of rocking motions on a tablet [2] (see Figure 2). Since dedicated physical degrees of freedom are provided for the third dimension, these modified mice should outperform a

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Figure 3: A sample of Fee moving 6 DOF devices- 'T~ing mice."(a) The "Bc¢" deJignedby C.Ware [I 9]; (b) The CricketTM, manufacturedby Digital Image Design Inc., NewYork NY, USA;(c) The MITS Glove,designedby the author,consistsof a BirdTM tracker and a clutch.See pale 102 for color Image. conventional mouse that operates by means of simple mode switching. (One common mouse switching technique, f o r example, is that pressing and holding a mouse button down switches vertical mouse cursor m o t i o n t o motion in the depth dimension). It was shown that in a 3D positioning task, the rockin' mouse was 30 percent Paster in comparison to

a standard mouse tablet [2]. On the other hand, since the depth dimension is operated by a behavior and muscle groups different from those of the x-y mouse motion, it can be difficult t o produce simultaneous, coordinated motion with either the roller mouse or the rockin' mouse.

"Flying" Mice Given the success of the mouse in 2D interfaces, it is natural to attempt to make a flying mouse - - a mouse that can be moved and rotated in the air For 3D object manipulation. Indeed many such devices have been made. Theoretically, a mouse is a free-moving, i.e. isotonic device.VVhen using such a device, the displacement of the device is typically mapped to a cursor displacement.This type of mapping (transfer function) is also called position control. Figure 3 shows a few examples of 6 DOF isotonic position control devices. Host of these devices are i n s t r u m e n t e d w i t h a magnetic tracker for 6 DOF sensing. The advantages of these "flying mice" devices are: • Easy t o learn, because of the natural, direct mapping. • Relatively fast speed. Studies have shown that 6 DOF isotonic position control devices tend to outperform other type of devices in speed. This was particularly true for novice users [21, 23, 25] (see Figure 4). However, there are many disadvantages to this class of devices: • Limited movement range. Since it is posit i o n c o n t r o l , hand m o v e m e n t can be mapped to only a limited range of the display space. In the case of standard 2 DOF mouse, this problem can be solved by making i¢ a "relative" device. One can lift the mouse up and put it down at a new location of the mouse pad. Similarly, one can also use a clutch (Figure 3(::) in a 6 DOF isotonic position control device. • Lack of coordination. In position control, object movement is directly proportional t o hand/finger m o v e m e n t and hence

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Rgure5: Coordinationas measuredby inef~c/encyin free moving position contro/vs,in elas',icrate control. Signi~can~longermovementwas "~wasted"with the free mov/ngdevice.See [23] far details. constrained t o anatomical limitations: joints can only rotate to a certain angle. These limitations prohibit well-coordinated movement, particularly when the user has to reclutch o r reposition the hand (finger) relative to the input device surface (see Figure 6). See [23] f o r detailed discussion on coordination (see Figure 5). • Fatigue.This is a significant problem with free moving 6 DOF devices because the user's arm has to be suspended in the air without support.The mouse did not have such a problem because it stays on the deskrop. One can rest the arm and hand on the desktop surface when operating a mouse, but not with the flying mice. • Difficulty of device acquisition.The flying mice lack persistence in position when released. W i t h a mouse o r trackball, when released by the hand, it stays in position. This is nor true with a stylus, nor with any of the flying mice.This property of not "staying put" inhibits some classes of interaction. Such devices may have to be put on desk and picked up for the next transaction. In the case of a glove, this is even more problematic,

Form Factor Matters O f course, there are many variations within each class of devices. One such variation is the form factor of the control handle (shape and size). As shown in Figure 3, there has been a variety of shape and size used in constructing free moving 6 DOF input devices. Some of these devices, such as the glove implementation (Figure 3c) require manipulation w i t h wrist and arms, but exclude the fingers. Figure 6 shows an alternative design, based on the very same sensor with a different shape and size that do allow the participation of the fingers that have higher dexterity. It was shown that significant performance advantage could be gained with such a design [22]. See figure 7.

Computer Graphics November1998 51

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"Desktop" Devices The alternative to free moving input devices, are devices that are mounted on a stationary surface. We may call these desktop devices. Figure 8 shows some examples of 6 D O F " j o y s t i c k " devices that fall into this class. C o m m o n to such devices is a self-centering mechanism. They are either isometric devices that do not move by a significantly perceptible magnitude o r elastic devices that are springloaded. When tension is released from the handle, the handle returns to a null position. Typically these devices w o r k in rate control mode, i.e. the input variable, either force o r displacement, is mapped onto the velocity of the cursor. In other words, the cursor position is the integration of input variable over time. Hence the t e r m f i r s t o r d e r c o n t r o l . In c o n t r a s t , in the case of the free m o v i n g ( i s o t o n i c ) devices, i n p u t variable (device displacement) is scaled to position (location and orientation) itself. Hence the term zeroorder control.

Compatibility Between Resistance and Transfer Function W i t h the p r o p e r clutching mechanism, it is conceivable to implement an isometric device in position control mode or an isotonic device in r a t e c o n t r o l m o d e (see Figure 9) Interestingly, these t w o combinations tend to produce p o o r user performance (see Figure 10).The reason is q u i t e simple: the selfcentering mechanism in an isometric device facilitates the "start, speed-up, maintain speed, slow-down and stop" cycle in rate c o n t r o l . T h e later half of the cycle is somewhat automatic with the self-centering mechanism in isometric devices.With a free moving device, one has to deliberately return to the null position.

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Rate Control

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Figure 8:A sample of desktop 6 DOF input devices.A sample of input devices for 6 DOF manipulation: (a) The SpaceballTM is an isometric device manufactured by Spaceball Technologies Inc., Boston, MA, U.S.A.(b) The SpaceMasterTM is an elastic device with a small range of movement (5 mm in translation and 15°in rotcrdon),manufactured by BASYS GmbH, Erlangen, Germany. (c) The Space Mouse TM is an elastic device with slight movement (5 mm in translation and 4° in rotation). It was initially designed by DLR, the German aerospace research establishment, manufactured by Space Control Company, Malching, Germany and marketed by Logitech, Fremont, CA, U.SJ~.See page 102 for color image.

Figure 9:Two input device design dimensions:transfer function vs. controller resistance.

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T h e Pros and Cons of Desktop 6 D O F Devices When used in rate control, an isometric device offers the following advantages: • Reduced fatigue, since the user's arm can be rested on the desktop. • Increased c o o r d i n a t i o n . The integral transformation in rate control makes the actual cursor movement a step removed f r o m the hand anatomy, resulting in greater coordination (see Figure I I) [23]. • Smoother and more steady cursor move° menr. The rate control mechanism (integration) is a low pass filter, reducing high frequency noises. • Device persistence and faster acquisition. Since these devices stay stationary on the desktop, they can be acquired m o r e easily. On the other hand, isometric rate control devices may have the following disadvantages: • Rate control is an acquired skilI. A user typically takes tens of minutes, a signifi-

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Figure 15:A single arm mu/t/-DOFarmature input device [9]. See page 102 for color image. Figure 12:A prototype of a 6 DOF Elastic Genera/purp0se Gr/p (EGG)[2 I, 20]. See page 102 for color image.

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centering mechanism needed for rate control. Figure 12 shows a prototype of a 6 DOF elastic rate control input device, dubbed EGG (elastic general-purpose grip).A similar suspension structure had been used for different purposes [6]. Since a user can feel both the pressure and the displacement with an elastic device, a stronger feedback is provided (see [21] Chapter 3 for derailed neuro-physiological analysis). However, the use of spring loading is not without tradeolf. The more displacement for the same force is provided, the stronger the kinesthetic feedback is provided, but the weaker the self-centering mechanism is for rate control compatibility (See [21] Chapter 3 for this two-factor analysis of elastic devices). When optimized, the appropriate amount of elasticity does improve a user's performance. This is particularly true at the early learning stages (see Figures 13 & 14).

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cant duration for learning c o m p u t e r interaction tasks, to gain controllability of isometric rate control devices. It may take hours of practice to approach the level of isotonic posiUon speed [21,25]. • Lack of control feel. Since an isometric device feels completely rigid, insufficient feedback is provided to the user at the k i n e s t h e t i c channel. Kinesthetic (or proprioceptive) feedback can be critical to user's conrrol performance. Elastic Devices An elastic device moves proportionally to rhe force applied to it and yet maintains the self-

Another class of multi DOF input devices are mechanical armatures. Some of these are specialized and geometrically compatible with the graphical object being controlled so as to enable the posing of computer graphics characr.ers more-or-less using puppeteering techniques.This is a technique that has been used by ILM, f o r e x a m p l e [10]. Digital Image Design Incorporated's "Monkey" [5] as seen in the cover of this special issue and the armatures f r o m Puppet W o r k s [ I S ] are commercially available examples of this class of technology. While strong in their intended, specialized purpose, their use is limited. They can do an excellent job for some types of character posing, but their applicability to interaction in general is limited, at least in this "puppet" type configuration. One option that can bring armatures much closer to the generality seen with the other devices discussed occurs if they are configured as a single arm. This can be done with either rhe DID or Puppet Works devices, and is the standard configuration for other armatures, such as Immersion Corp's MicroScribe illustrated in Figure 15 [9].

In this configuration, the armature is actually a hybrid between a flying-mouse type of device and a desktop device. It is like a desktop device in that it is typically mounted on the desktop, and consumes a small footprint. On the other hand, it is like a flying mouse in that manipulating the end point of the arm in space provides the desired 6 DOF position data. Conceptually, these are near isotonic - - with exceptional singularity positions - - position control device like a flying mouse and thus share many of the pros and cons of isotonic position control discussed earlier. In addition, this approach has the following particular advantages: • N o t susceptible to interference; most flying mice, based on magnetic tracker, have susceptibility to electromagnetic interference as well as to metal objects, • Less delay:,response is usually better than most flying mouse technology, whose built-in electromagnetic noise reduction filters introduce significant time delay. • Can be configured to "stay put," when friction on joints is adjusted and theref o r better for device acquisition. • Some, like the MicroScribe, have potential to serve double duty as 3D digitizer (which is what it was designed for) as well as general input devices On the other hand, they also have some particular drawbacks: • Device acquisition (especially if they do not "stay put"). • Fatigue: as with flying mouse. • Constrained operation.The user has to carry the mechanical arm to operate, which is more cumbersome than most flying mice tethered by a cable.At certain singular points, position/orientation is awkward. This class of devices can also be equipped w i t h force feedback, as w i t h SensAble Technology's Phantom Device [ 1 7 ] . W h i l e showing some promise and with novel user experiences, force feedback devices have yet to demonsa-are their real benefit in the lab or in practice for mainstream applications. Ir is, of course, very interesting as a research area.

Conclusions From this brief and incomplete guided tour, one can conclude thor the complexity of 6 DOF input is far from being solved. None of the existing devices fulfills all aspects of usability requiremenr for 3D manipulation. A six degree of freedom device that suits all, or the majority of, 3D applications has yec to he developed. However, the research conducted so far has offered implications for potential improvement - - with many insights into the characteristics, pros and cons of various designs. These insights should help the selection of various types of devices for different

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tasks. For example, when speed and short learning is a primary concern (such as in video games), free moving devices are most suitable. When fatigue, control trajectory quality and coordination are more important, such as in teleoperation, isometric or elastic rate control devices should be selected.This article has only covered a few aspects of 6 DOF input device design. Many other areas, such as the cooperation of two hands in 3D input [8] and those covered by other articles in this issue, are equally important. Further research, both developmental and experimental, is certainly needed.

Acknowledgments I thank Paul Milgram and Bill Buxton for their longstanding mentorship. Some of the studies cited in this paper were conducted at the University of Toronto with funding support from ITRC, NSERC and DCIEM. Bill Buxton reviewed the article and co-authored the Multi-DOF Armatures section.

References I. Bahrick, H. P.,V~. E Bennett and P. M. Fi~cs. "Accuracy of positioning responses as a function of spring loading in a control;' Journal of Experimental Psychology, 49(6), 1955, pp. 437-444. 2. Balakrishnan, R.,T. Baudel, G. Kurtenbach and G. Fitzmaurice. "The Rockin'Mouse: Integral 3D manipulation on a plane,"

Proceedings of CHI '97 Conference on Human Factors in Computing Systems, 1997. 3 Burrows, A. A."Control feel and the dependent variable" Human Factors, 7(5), 1965, pp. 413-421. 4. Chen, M., S. J. Mountford and A. Sellen. "A study in interactive 3-D rotation using 2-D control devices," Proceedings of ACM SIGGRAPH 88, 1988. 5. DID Monkey, h t t p : l l w w w . d i d i . c o m l

www/areas/products/mon key2/index. html. 6. Galyean,T.A. and J. F. Hughes. "Sculpting:An interactive volumetric modeling technique" Computer Graphics 25(4), 199 I, pp. 267-274. 7. Hinckley, K.,J.Tulio, R. Pausch, D. Proflitt and N. Kassell."Usability Analysis of 3D Rotation Techniques" Proceedings of ACM Symp. User Interface Software and Technology, 1997. 8. Hinckley, K., R. Pausch,J. C. Goble and N. F. Kassell. "Passive real-world interface props for neurosurgical visualization" Proceedings

of CHr94:ACM conference on Human Factors in Computing Systems,Boston, 1994. 9. Immersion Corp., h t t p : / / w w w . i m m e r s e .

com/. 10. Knep, B., C. Hayes, R. Sayre and T.Williams. "Dinosaur input device," Proceedings of

CHI'95: ACM Conference on Human Factors in Computing Systems, 1995. I I. Orlansky, J. "Psychological aspects of stick and rudder controls in aircraft,"

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Aeronautical Engineering Review, January 1949, pp. 22-3 I. 12. Parsons, L."lnability to reason about an object's orientation using an axis and angle of rotation," Journal of Experimental

Psychology: Human Perception and Performance, 21 (6), 1995, pp. 1259-1277. 13. Perry, T. S. and J. Voelcker. "Of mice and menus: Designing the user-friendly interface" IEEE Spectrum, September 1989, pp. 46-5 I. 14. Poulton, E. C. Tracking skill and manual control. NewYork:Academic Press, 1974. 15. Puppetworks, http:/Iwww.puppet-

works.coml. 16. Schmidt, R.A. Motor control and learning - A Behavioural Emphasis. (2nd ed.): Human Kinetics Publishers, Inc., 1988. 17 SenSable,http://www.sensable.com/. 18. Venolia, D."Facile 3D direct manipulation"

Proceedings of INTERCHI'93: ACM Conference on Human Factors in Computing Systems, Amsterdam, The Netherlands, 1993. 19. Ware, C."Using hand position for virtual object placement" The Visual Computer, 6, 1990, pp. 245-253. 20. Zhai, S."lnvestigation of feel for 6 DOF inputs: isometric and elastic rate control for manipulation in 3D environments,"

Proceedings of The Human Factors and Ergonomics Society 3 7th Annual Meeting, Seattle,WA, 1993. 2 I. Zhai, S. Human Performance in Six Degree of Freedom Input Control. Ph.D. Thesis, University of Toronto, 1995,

http://vered.rose.toronto.edulpeoplel shumin_dir/papers/PhD_Thesis/top_ page.html. 22. Zhai, S., P. Milgram and W. Buxton. "The influence of muscle groups on performance of multiple degree of freedom input control," Proceedings of CH1'96: ACM

Conference on Human Factors in Computing Systems, 1996. 23. Zhai, S. and P.Milgram."Quantifying coordination in multiple DOF movement and its application to evaluating 6 DOF input devices," Proceedings of CH1"98: the ACM

Conference on Human Factors in Computing Systems, 1998. 24. Zhai, S. and P. Milgram. "Human performance evaluation of isometric and elastic rate controllers in a 6 DOF tracking task"

Proceedings of SPIEVol.2057 Telemanipulator Technology, Boston, MA, 1993. 25. Zhai, S. and P. Milgram."Human performance evaluation of manipulation schemes in virtual environments," Proceedings of

VRAIS'93: the first IEEE Virtual Reality Annual International Symposium,Seattle,WA, 1993.

Shumin Zhai is a Research Staff Member at the IBM Almaden Research Center where he conducts research and innovative development in input devices and interaction techniques, theoretical modeling of human computer interaction (HCI), advanced graphical user interfaces and computer vision-based next generation multi-modal interaction techniques. He received his Ph.D. degree from the University of Toronto where he worked on 3D interfaces and six degrees of freedom input control.

Shumin Zhai IBM Almaden Research Center 650 Harry Road San Jose, CA 95123 Tel: + 1-408-927- I I 12 Email: [email protected] Web: h t t p : l l w w w . a l m a d e n . i b m . c o m l c s l people/zhai/.

FROM

THE

EDITOR

Explore the World of Computer Gaming and Computer Graphics Gordon Cameron SOFTIMAGE, Inc. The February 1997 issue of Computer Graphics contained a focus (expertly guest edited by Mike Milne) on the entertainment industry, but we chose to save an important area of this industry for later investigation. It's with great pleasure that I present that focus on the computer games industry in this May 1998 issue of Computer Graphics. Back in the early 'B0s when I was still in school, I was enthusiastically coding away on a variety of early machines such as the Sinclair ZX8 I, Oric- I, Atari 800XL and Atari ST. At the same time, I spent a great deal of my hard-earned paper-round cash on games for these machines, so it was with great excitement that I recently discovered an on-line "shrine" to the games and their progremmers. James Hague had painstakingly put together a list of"classic game programmers" and in addition had interviewed several of the more revered game designers for a fascinating electronic publication entitled Halcyon Days. Around the same rime, I was trying to put together an issue on computer graphics and the games industry, and so contacted James to see if he might be interested in guest editing such an endeavour. Luckily, he accepted, and ~ e issue in your hands now contains the resulting focus. Over the past decades, computer games have evolved at a remarkable pace. Many of the early titles pushed the platform capabilities, but more recently the games industry is proving one of the major factors in pushing computer graphics in feneral forward at a breakneck pace -- many of the new titles are generating groundbreaking research of their own, and forcing the hardware (and standards) to evolve co keep up,You can pick up a consumer PC with graphics comparable (or superior) to the workstations of a short time ago, at a fraction of the cost today, and this trend is really shaking up our industry and forcing innovations at a startling rate. At the same time, it is worthwhile to Jook back at the amazing things people were doing in the earlier days of computer gaming, with far more limited resources (both technical and human). These early pioneers were

performing minor miracles to achieve effects that today may look somewhat dated bur in their time were bleeding edge, whilst still managing to keep in mind that most important, yet too-oft neglected, aspect --- gameplay. James has done a superb job in gathering together a collection of thoughtful and personalarticles from both past and present which together form a snapshot of the world of computer gaming and computer graphics. My thanks go out to all those who contributed, and especially to James for working under extremely tight deadlines.

Also, once again we have a tremendous series of columns. If you have any comments, I encourage you to drop a note to the columnisl3. For any general questions, ideas, commerits, etc, please feel free to contact me at one of the addresses listed below and I'll do my best to answer -- thank you s o much for your letters over the last few months and, please, keep them cominl! The majority of notes from the last issue complimented the content, for which I'm extremely grateful on behalf of the contributors. However, rather than print only these, I've decided to wait until we have a broad cross section of letters to use in the next Letters column. Until next issue, all the very besT,,and I look forward to seeing some of you at the upcoming SIGGRAPH 98 25th anniversary conference. Gordon Cameron Software Development SOFTIMAGE,Inc. 3510 boul.St-~urent Suite 400 Montn~, Quebec,H2X 2V2 Canada Tel:+ I-51A,aA,5-1636 ~ 3445 Fmc+ I-514-845-5676 Email:Eordon_cameron~sll~q-aph-ori

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