http://vr.isdale.com

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• http//vr.isdale.com
• jerry_at_isdale.com

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VE Technology ReviewOutline

• Introduction
• Interface Technology
• Processing Technology
• Network Virtual Environments
• Project Development
• VR Systems
• Applications
• Resources

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2 Introduction

• Virtual Reality is a fairly complex technology
  with few complete off the shelf solution bundles.
  
• Creating a working application often requires a
  systems approach with fairly broad range of
  knowledge and talent.
• 2.1 What Is VR
• 2.2 Why Use VR
• 2.3 How- VE Technology
• 2.4 Where next? Research Issues of VR

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2.1 What Is VR

• 2.1.1 Many Names of VR
• 2.1.2 Definition of VR
• 2.1.3 Taxonomy Spectrum
• 2.1.4 Range of VR Systems
• 2.1.5 Early VR History

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2.1.1 Many Names of VR

• Virtual Reality
• Virtual Environment
• Artificial Reality
• Computer Generated Environment
• Computer Simulated Environment

• Synthetic Environment
• Spatial Immersion
• Cyberspace
• Virtual Worlds
• Virtual Presence
• Metaverse

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2.1.2 Definition of VR

• (courtesy Michael Capp, Naval Postgraduate
  School)
• A Computer-Generated, 3D Spatial Environment in
  Which Users Can Participate in Real-time.
• Virtual Environments Can Be
• Fully Immersive, Encompassing Worlds
• Augmentations (Overlay) to the Real World
• Through the Window Worlds (Non-immersive)

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2.1.3 Taxonomy Spectrum

• VR is an area within the multidimensional
  taxonomy spectrum of computer systems.
• 2.3.1.1 Some Related Technologies
• 2.3.1.2 VR vs 3D Computer Graphics

network
multimedia
sensory
interactivity
physical size
costs
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2.3.1.1 Some Related Technologies

• CAD
• Vehicle/Flight Simulators
• Computer animation/special effects
• PC/Video Games
• Interactive Images
• Augmented Reality
• Combined real world and computer generated
  environment
• Video AR Real world video with generated overlay
• See Through AR Generated display is
  semi-transparent
• Tele-Presence
• Teleconferencing
• Remote robotic control
• Collaborative Systems

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2.3.1.2 VR vs. 3D Computer Graphics

• Interface devices techniques
• Free range navigation
• Manipulation of world entities
• Immersion Presence

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2.3.1.2 Immersion

• Sensory Immersion
• Psychological Immersion
• Produced by
• Enveloping environment
• Natural interaction (view, manip.)
• Realism?
• Responsiveness?
• Fidelity
• Update rate

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2.3.1.2 Presence

• (Source Lombard, et al "Measuring Presence"
  http//www.presence-research.org/presence2000.html
  )
• "The Perceptual Illusion Of Non Mediation."
• Six different conceptualizations of presence
• 1) Presence as social richness
• the "warmth" or "intimacy" possible via a medium
• 2) Realism
• perceptual and/or social
• 3) Transportation
• the sensations of "you are there," "it is here,"
  and/or "we are together"
• 4) Immersion
• in a mediated environment
• 5) Social actor within medium
• e.g., parasocial interaction
• 6) Medium as social actor
• e.g., treating computers as social entities

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2.1.4 Range of VR Systems

• Interactive Images
• World in a Window
• Desktop System
• Game Machine
• HMD Systems
• Rooms
• (Networked) Simulators
• Persistent, Shared Virtual Worlds

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2.1.5 Early VR History

• Fictional Accounts
• Bradbury, The Veldt, 1950
• Zelazney, Dream Master, 1966
• Vinge True Names, 1981
• Gibson Cyberspace, 1984, etc
• Systems and Events
• Mort Heilig, Sensorama, 1956
• Ivan Sutherland, The Ultimate Display (FIPS 1965)
• Visual Simulator Industry (GE 1975, Simnet 1985)
• Myron Kruger, Video Place 1983
• NASA VIVED, VPL, 1985
• Scientific America, 1987
• Meckler VR conferences early 1990s

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2.2 Why Use VR

• 2.2.1 Why an immersive interface?
• 2.2.2 VE Applications
• 2.2.3 Why Not Use VR

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2.2.1 Why an immersive interface?

• Real environment is hazardous or costly
• Environment encompasses large virtual spaces
• Large number of parameters manipulated
• Tasks are of a hands-busy nature
• Perspective is important
• Need presence to understand environment
• High Tech is Cool

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2.2.2 VE Applications

• See Section 8 for more details
• Entertainment
• Design and Development
• Training
• Education
• Information / Scientific Visualization
• Collaboration / Community
• Medicine / Mental Health
• Marketing

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2.2.3 Why Not Use VR

• Cybersickness
• System Costs (equipment, space, people)
• Development Complexity
• Appropriate Content Design
• Cumbersome Equipment

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2.3 How- VE Technology

• 2.3.1 Programmatic
• 2.3.2 Displays
• 2.3.3 Input Devices
• 2.3.4 Processor Hardware
• 2.3.5 Interaction Techniques
• 2.3.6 World Database
• 2.3.7 Application Software
• 2.3.8 Network Connectivity (Optional)

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2.3.1 Programmatic

• Project Management
• Technical Systems Engineering
• Artistic World Design
• Business Marketing, Funding

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2.3.2 Displays

• Visual
• Audio
• Haptic
• Other displays

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2.3.2 Input Devices

• Tracking systems
• Wide variety of interface devices

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2.3.3 Processor Hardware

• Graphics hardware/software
• Main processor
• Multiple processors

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2.4 Where next? VE Research Issues

• Increased realism and scene complexity
• Decreased lag (action to reaction time)
• 3d User interfaces and interaction
• Multi-sensory output
• Seamless collaboration
• Behavior Simulation
• Component Framework and Tools
• VE Design Theories

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3 Interface Technology

• 3.1 Interface Device vs Interface Technique
• 3.2 Universal Interaction Tasks
• 3.3 Display
• 3.4 Inputs

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3.1 Interface Device vs Interface Technique

• A device can be used in may ways, effectively or
  otherwise
• Device Hardware (device, cabling, interface port)
• Device Driver
• Interaction Technique (Software use of device)

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3.2 Universal Interaction Tasks

• 3.2.1 Passive Experience
• 3.2.2 Navigation
• 3.2.3 Selection
• 3.2.4 Manipulation
• 3.2.5 System control

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3.2 Universal Interaction Tasks

• 3.2.1 Passive Experience
• Not really "interaction", simply experiencing
  displays
• 3.2.2 Navigation
• Locomotion motor component
• Way-finding cognitive component
• 3.2.3 Selection
• Choosing one or more objects from a set
• 3.2.4 Manipulation
• Specification of object position orientation
• Specification of scale, shape, other attributes
• 3.2.5 System control
• All other interactions, usually accomplished via
  commands
• May be composed of other tasks

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3.3 Display

• Display device which presents perceptual
  information
• Often display used to mean visual display
• Goal display devices which accurately represent
  perceptions in simulated world
• 3.3.1 Display What
• 3.3.2 Visual
• 3.3.3 Audio
• 3.3.4 Haptics
• 3.3.5 Other Displays

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3.3.1 Display What

• Environment Display
• Control Display
• cockpit, buttons, menus, etc.
• Systems Monitor
• behind the scenes details
• man behind the curtain

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3.3.2 Visual Displays

• Stimulus light of wavelengths 350-750 nm
• Visual dominance 50 of brain involved in
  processing!
• 3.3.2.1 Human Visual System
• 3.3.2.2 Desktop Displays
• 3.3.2.3 Head Mounted Displays (HMD)
• 3.3.2.4 Projection Displays
• 3.3.2.5 Other Visual Displays
• 3.3.2.6 Which Visual Display to Use?

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3.3.2.1 Human Visual System

• Physiology of Eyes
• Fovial/Peripheral Vission
• Rods periphery, motion, BW, sensitivity
• Cones fovea, static, color, acuity
• Perception Brain
• 3.3.2.1.1 3D depth cues
• 3.3.2.1.2 Issues for Visual Displays

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3.3.2.1 3D depth cues

• (courtesy Doug Bowman)
• Several different types of cues used by human
  visual system
• 3.3.2.1.1.1 Static monocular cues
• 3.3.2.1.1.2 Stereopsis
• 3.3.2.1.1.3 Motion parallax
• 3.3.2.1.1.4 Oculomotor cues
• 3.3.2.1.1.5 Accommodation-convergence mismatch

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3.3.2.1.1 Static Monocular Cues

• Types of Monocular Cues
• Occlusion,
• relative size,
• linear perspective,
• texture gradient,
• aerial perspective,
• shading,
• relative height
• Can lead to depth illusions
• man on hand photo, Ames room

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3.3.2.1.1.2 Stereopsis

• Static, binocular cue
• Each eye gets a slightly different image
• Only effective within a few feet of viewer
• Many implementation schemes

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3.3.2.1.1.3 Motion Parallax

• Dynamic, monocular cue
• Near objects move faster than far objects
• Generally more important than stereo!

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3.3.2.1.1.4 Oculomotor Cues

• Based on information from muscles in the eye
• Accommodation lens shape
• Convergence gaze direction

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3.3.2.1.1.5 Accommodation-Convergence Mismatch

• Std. Stereo displays confuse the brain based on
  oculo. Cues
• Only true 3d displays can provide these
  correctly

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3.3.2.1.2 Issues for Visual Displays

• Resolution (angular range of pixel)
• Field of View (angular range of display)
• Image Update Rate

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3.3.2.2 Desktop Displays

• Standard Monitor
• Multiple-Monitors

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3.3.2.2.1 Stereo Techniques

• LC Shutters (glasses or screen)
• 3-D Monitors
• Head Tracking for motion cues and eye position

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3.3.2.3 Head Mounted Displays (HMD)

• Symbol of VR to most people
• Display and Optics mounted on Head
• May or may not fully occlude real world
• 3.3.2.3.1 HMD Description
• 3.3.2.3.2 HMD Issues

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3.3.2.3.1 HMD Description

• Support System
• Display (pixels vs triads)
• Optics
• Binocular/Monocular/Biocular
• Tracker strongly recommended

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3.3.2.3.2 HMD Issues

• Cumbersome to wear
• Single user
• Small Field Of View
• Adjustable Field of View
• Exit Pupil Size
• Inter-pupil distance
• Resolution
• Costs

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3.3.2.4 Projection Displays

• One or more projectors and screens
• Front or Rear projected
• Larger size than monitors
• Dont occlude reality
• Viewed by many people at a time
• 3.3.2.4.1 Example Projection Displays
• 3.3.2.4.2 Projection Display Issues

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3.3.2.4.1 Example Projection Displays

• Table ( 1 or more surfaces)
• Wall (curved, flat)
• Room (3 to 6 sides)
• Dome (desk to Planetarium))

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3.3.2.4.2 Projection Display Issues

• Projector, screen and space are main
• Seam blending, and Sync issues
• Brightness (front/rear projection)
• Visibility Angles

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3.3.2.5 Other Visual Displays

• Push BOOM - Fakespace Labs
• WindowVR - Virtual Research
• Tablets - Wacom
• Cybersphere - VR Systems

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3.3.2.6 Which Visual Display to Use?

• Research Product Design Topic
• Cost Monitor, HMD, Projection
• HMD for 360, close up, block reality, single user
• Group display projection variety

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3.3.3 Audio

• 2nd most studied sense
• Adds tremendously to experience, if well executed
• Stimulus disturbance of molecules in a medium
  (air)
• Perceptions pitch, loudness, location
• 3.3.3.1 Sonification of Interface
• 3.3.3.2 Sound Effects
• 3.3.3.3 Environmental Audio
• 3.3.3.4 Spatialized Audio
• 3.3.3.5 Speech Generation
• 3.3.3.6 Audio Display Devices

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3.3.3.1 Sonification of Interface

• Alerts and Interaction Feedback
• Ambient Sound
• Modern systems are too quiet, lack operating
  noise
• David Theil MS Research

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3.3.3.2 Sound Effects

• Classic Multimedia, game tool
• Intensity fall-off (1/d2)
• Headphones also block out real-world noises
• Ambient sound (e.g. stream, crowd)

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3.3.3.3 Environmental Audio

• Sound occlusions
• Reverberation from surfaces
• Room acoustics
• Environmental Audio
• Direct X API

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3.3.3.4 Spatialized Audio

• 2 ears allow localization
• Works well in plane of ears
• Interaural intensity differences
• Interaural time differences
• Pineal shape effects
• Head Related Transfer Function (HRTF)

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3.3.3.5 Speech Generation

• Avoids text display which breaks illusion
• Extra processing required
• Vocal Tract simulation
• Prerecorded words, phonemes and diphones
• Intelligibility may require practice
• Lacks tonality, rhythm, emphasis, general
  expressiveness

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3.3.3.6 Audio Display Devices

• PC sound boards (mid to high range)
• External synthesizer, mixer
• Stereo Headset (with or w/o HRTF)
• Stereo speakers (HRTF with cancelation)
• Multiple Speakers
• Bass Shaker Speaker
• Amplifiers, wiring

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3.3.4 Haptics

• Adds greatly to VE when you interact with objects
• Tactile vs Kinematic
• 3.3.4.1 Tactile
• 3.3.4.2 Force
• 3.3.4.3 Motion Platform
• 3.3.4.4 Issues for Haptics

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3.3.4.1 Tactile

• Temperature, skin curvature and stretch,
  velocity, vibration, slip, pressure and local
  force
• Vibration fairly easy and cheap
• pager parts
• Texture is harder to reproduce
• pin arrays
• Gross vs local temperature

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3.3.4.2 Force

• Force feedback, Force reflection
• Exoskeleton (CyberGrasp)
• Armature (Sensable Phantom)
• PC Joysticks Steering wheels
• Mice (vibration or forces)

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3.3.4.3 Motion Platform

• Vestibular and Proprioception
• Impulse Force and Onset Cues
• Washout
• Degrees and Range of Motion (1, 3, 6)
• Stewart Platform (aka Hexapod)
• Walking Simulators
• Virtual Motion Headset (eletrostimulation)

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More Motion Platforms
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3.3.4.4 Issues for Haptics

• Detailed Geometric Modeling
• Complex Force Calculations
• Input Coupling
• Often requires separate processor

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3.3.5 Other Displays

• Wind
• Heat
• Smell
• Muscle Control

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3.4 Inputs

• Hardware that allows the user to communicate with
  the system
• Discreet, event based devices
• Continuos, sampled devices
• 3.4.1 Trackers
• 3.4.2 Gloves
• 3.4.3 Wands
• 3.4.4 Speech Recognition
• 3.4.5 Gesture Recognition
• 3.4.6 Locomotion Devices
• 3.4.7 Other Devices

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3.4.1 Trackers

• Measure position and/or orientation of a sensor
• Degrees of freedom (DOFs)
• Position (3 axis)
• Rotation (3 axis)
• Mostly used for tracking head and hands
• Some systems provide whole body tracking
• Object Tracking (tablet, controls, etc.)
• Preprocessing system required
• Very common, often essential part of VE

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3.4.1.1 Types of Trackers

• Mechanical
• Armature with position sensors
• Electromagnetic
• AC or DC field emmitors/sensors
• Compass
• Optical
• Target tracking (led, ping pong balls)
• Full Vision or simply targets
• Acoustic
• Ultrasonic
• Inertial
• Acceleration and impulse forces
• GPS
• Outdoor Augmented Reality
• Hybrid

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3.4.1.2 Tracker Issues

• Latency and lag
• Interference
• Noise
• Tethering / encumbrance
• Range

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3.4.2 Gloves

• The other "classic" VR device
• Finger position sensing gloves
• Discrete gloves
• tips touching Fakespace Pinch
• Armature tracked
• Bend sensors (optical, resistive, other)
• Tracker required for overall position/orientation

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3.4.3 Wands

• Free space joystick
• Buttons plus tracker
• Variety of shapes and configurations

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3.4.4 Speech Recognition

• Frees hands for other devices
• Discreet Command vs Continuos Speech
• Dialog Management
• Ambient Noise
• False positives
• Training

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3.4.5 Gesture Recognition

• Single posture
• Multiple posture
• Posture plus motion
• Face, hand, arm gestures
• gloves, video, etc.

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3.4.6 Locomotion Devices

• Tread mill,Stair Stepper
• Skates, walking in place
• Bicycle, Unicycle
• Tilt platform (skate/snow board)

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3.4.7 Other Devices

• Keyboards (wearable)
• Advanced Mice/Joysticks
• Muscle contraction
• Brain wave
• Eye tracking
• Osmose Breathing
• http//www.dgp.utoronto.ca/people/BillBuxton/Input
  Sources.html

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4 Processing Technology

• 4.1 Basic VR System Loop
• 4.2 World Model - VE Database
• 4.3 World behaviors
• 4.4 Display Rendering

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4.1 Basic VR System Loop

• Input Processing
• Simulation Update
• Rendering (to displays and network)
• Processing Latency between input sensing and
  display
• Multi-threaded processing

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4.2 World Model - VE Database

• 4.2.1 Extended Scene Graph
• 4.2.2 3D Modeling
• 4.2.2.1 Geometry Types
• 4.2.2.2 3D Object Scanning
• 4.2.2.3 Virtual Human Avatar
• 4.2.2.4 Texturing
• 4.2.2.5 Levels of Detail
• 4.2.3 Lighting
• 4.2.4 World Assembly

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4.2.1 Extended Scene Graph

• Scene Graph hierarchy of objects and spaces
  (geometry and lighting) with position
  orientation linkages
• Extended to include input devices (trackers,
  etc), sounds, behaviors, links to other worlds,
  etc.

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Scene Graph
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4.2.2 3D Modeling

• Much in common with
• 3D Computer Graphics and Animation
• 4.2.2.1 Geometry Types
• 4.2.2.2 3D Object Scanning
• 4.2.2.3 Virtual Human Avatar
• 4.2.2.4 Texturing
• 4.2.2.5 Levels of Detail

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4.2.2.1 Geometry Types

• Polygon Models
• 3D Curve Surfaces
• Solid Modeling (voxels, solid geometry)
• Procedural (Fractals, etc.)
• Articulated Objects
• Landscape (height field)

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4.2.2.2 3D Object Scanning

• Quickly produce models of real objects
• Point Clouds and Post Processing
• Volume (small, medium, large)
• Laser Digitizers
• White Light Digitizers
• Tracker-based Wand
• Photogrammetry (from photograph)

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4.2.2.3 Virtual Human Avatar

• Represents user and others in virtual world
• May or may not be humanoid
• Some standardization efforts
• MPEG-4,
• H-Anim
• Nat. Lib. Medicine Virtual Human Project
• not really avatar
• detailed human model from sliced cadavers
• extending to provide animation, behaviors

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4.2.2.4 Texturing

• Substitute image for geometric detail
• Highly effective
• Many techniques for texturing
• MIP maps (multi-level of detail)
• Reflectance Maps
• Bump Maps
• Solid Textures

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4.2.2.5 Levels of Detail

• Different model descriptions for same object
• Use lower complexity models when far away or
  cluttered scene
• Switching objects can cause artifacts
• Particular to Simulator and VE systems

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4.2.3 Lighting

• Diffuse, specular, ambient light
• Light Sources
• spot
• flood
• ambient
• colored
• object specific
• Light Maps
• radiosity
• global illumination

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4.2.4 World Assembly

• World vs Object Space
• Multiple Worlds
• Environmental Effects (fog, etc.)

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4.3 World Behaviors

• 4.3.1 Object Motion
• 4.3.2 Collision Detection and Response
• 4.3.3 Physical Simulation
• 4.3.4 Scripting
• 4.3.5 Area of Interest Culling
• 4.3.6 World Linking
• 4.3.7 Artificial Life

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4.3 World Behaviors

• 4.3.1 Object Motion
• Animation
• Constraints
• Motion Capture
• Simulation
• 4.3.2 Collision Detection and Response
• Very important for realism
• Many fast detection algorithms emerging
• Reactions may require force simulation

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4.3 World Behaviors

• 4.3.3 Physical Simulation
• FMA
• Modeling Newtonian Forces
• Kinematics and other forces
• Fake physics for expediency
• 4.3.4 Scripting
• Data flow programming
• Java and other scripting in VRML

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4.3 World Behaviors

• 4.3.5 Area of Interest Culling
• Reduce scene in memory by area of interest
• 4.3.6 World Linking
• Jumping to different world databases
• Web based links in VRML
• 4.3.7 Artificial Life
• Simulated life with goals, plans, etc.
• "Natural" selection and evolution
• Neural Net driven life forms

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4.4 Display Rendering

• 4.4.1 Real time 3D Graphics
• 4.4.1.1 Graphics Pipeline
• 4.4.1.2 Software Systems
• 4.4.1.3 PC vs Workstation
• 4.4.2 Non Visual Rendering

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4.4.1 Real time 3D Graphics

• 4.4.1.1 Graphics Pipeline
• 4.4.1.2 Software Systems
• 4.4.1.3 PC vs Workstation

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4.4.1.1 Graphics Pipeline

• Area Culling
• View Frustrum
• Clipping
• Hidden Surface
• Shading/Textures
• Rasterizing
• AntiAliasing
• Optimization

93
4.4.1.2 Software Systems

• OpenGL
• OpenPreformer
• IrisGL
• IrisPerformer
• DirectX
• VRML

94
4.4.1.3 PC vs Workstation

• PC board capability doubled every 6 months
• Slowed in expectation of Direct X v8
• delayed pending XBox
• Workstations have better bandwidth to memory
• can more and larger textures
• Simulator Image Generator
• Scene simulation often limited by culling and
  clipping
• Fixed frame rate - dynamic scene complexity
• OpenGL/DirectX dont support this well so PCs
  suffer

95
4.4.2 Non Visual Rendering

• Audio boards
• PC audio fairly sophisitcated
• Dedicated Audio PC w/LAN connection
• Loss of Aureal Technologies
• Haptic Processing
• Separate processor suggested

96
5 Networked Virtual Environments

• 5.1 Types of Networked VE
• 5.2 Challenges
• 5.3 Centralized Model
• 5.4 Distributed Model

97
5.1 Types of Net VE

• Streamed Browser Worlds (single user)
• Community Chat Worlds
• Collaborative Design Worlds
• Distributed Training Environments
• Internet Gaming

98
5.2 Challenges

• (courtesy D. Gracanin)
• Network Bandwidth
• Heterogeneity
• Distributed Interaction
• Real-Time System Design and Resource Management
• Failure Management
• Scalability (geography of scene, net distance,
  population,etc)
• Deployment and Configuration

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5.3 Centralized Model

• One computer (database) collects all data and
  sends updates to the users.
• Simple structure.
• Not scalable, the database is the bottleneck.

100
5.4 Distributed Model

• Each user maintains its own copy of the database.
• Updates are send to other users.
• Not scalable, the network is the bottleneck.

101
6 Project Development

• 6.1 Systems Engineering
• 6.2 World Authoring
• 6.3 Design Concepts
• 6.3.1 Usability Human Factors
• 6.3.2 VE Design Theory

102
6.1 Systems Engineering

• Creating a VE system requires integration of
  hardware, software and artistic creations
• Many interrelated issues between these domains
• Systems Engineering approach needed to manage
  these issues.
• Basic Project Management
• Software Engineering

103
6.2 World Authoring

• Much of the authoring tools and techniques are
  shared with other 3D graphics domains
• VR demands more speed from models
• trade-offs and special techniques for the world
  database

104
6.3 Design Concepts

• 6.3.1 Usability Human Factors
• 6.3.1.1 Goals of Interaction Design
• 6.3.1.1.1 Performance
• 6.3.1.1.2 Usability
• 6.3.1.1.3 Usefulness
• 6.3.1.2 Philosophies Of 3D Interaction Design
• 6.3.2 VE Design Theory
• 6.3.2.1 Styles of World Building
• 6.3.2.2 Church/Murray Aesthetics
• 6.3.2.3 Perceptual Opportunities

105
6.3.1 Usability Human Factors

• Usability as measure of quality
• VE Usability Research (U.Va, UK, etc.)
• 3D UI Web (http//www.mic.atr.co.jp/poup/3dui.htm
  l)
• Excellent detailed tutorials
• 6.3.1.1 Goals of Interaction Design
• 6.3.1.2 Philosophies Of 3D Interaction Design

106
6.3.1.1 Goals of Interaction Design

• (courtesy Doug Bowman, Virginia Tech.)
• Performance
• Efficiency
• Accuracy
• Productivity
• Usability
• Ease of use
• Ease of learning
• User comfort
• Usefulness
• Interaction helps meet system goals
• Interface relatively transparent so users can
  focus on tasks

107
6.3.1.2 Philosophies Of 3D Interaction Design

• (courtesy Doug Bowman, Virginia Tech.)
• Artistic Approach
• Base design decisions on Intuition about users,
  tasks, and environments, Heuristics, Metaphors,
  Common Sense, Aesthetics
• Adaptation/Inversion of existing interfaces (e.g.
  using 2D interface elements in a 3D environment)
• Scientific Approach
• Base design decisions on Formal characterization
  of users, tasks, and environments, Quantitative
  evaluation results, Performance requirements,
• Examples taxonomies, formal experimentation
• Both approaches can lead to guidelines
  principles

108
6.3.2 VE Design Theory

• Virtual Environment Design is a relatively new
  field, open to experimentation.
• Draws from many areas of design including
  Architectural Theory, Animation, Storytelling
• Benedikt's 1992 Cyberspace First Steps
• Chapter in forthcoming book
• "Handbook of Virtual Environments"
• 6.3.2.1 Styles of World Building
• 6.3.2.2 Church/Murray Aesthetics
• 6.3.2.3 Perceptual Opportunities

109
6.3.2.1 Styles of World Building

• Mike Heim, Art Center College of Design, Pasadena
  CA
• Additive
• Draw from pre-built libraries
• Authoring
• Create new objects and spaces
• Realistic Construction
• Reflects real world environments
• Fantastical Construction
• Capitalize on unique nature of VR

110
6.3.2.2 Church/Murray Aesthetics

• Forged by Clive Fencott from Janet Murray's
  aesthetics for interactive media, Doug Church's
  'Formal Abstract Design Tools', Mel Slater on
  co-presence, and Mike Heim's Transmogrification
• Agency
• Pleasure of being, or appearing to be in control
• Narrative Potential
• Ability to impart knowledge or tell story
• Presence and Co-presence
• Being there
• Transformation/ Transmorgrification
• Ability to do or be the unusual

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6.3.2.3 Perceptual Opportunities

• Characterization of the roles objects are
  intended to play in establishing purposive
  experience
• Sureties
• Denotative meaning and acceptance of environment
• Shocks
• Perceptual bugs, break illusion of environment
• Surprises
• Deliver connotative meaning purpose
• Attractors draw attention to areas of interest
  or situations
• Connectors support planning to achieve goals
• Retainers deliver specific objectives and
  rewards of world
• Perceptual Maps
• document relations between perceptual
  opportunities

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7 VR Systems

• 7.1 VR Software Features
• 7.2 Complete vs Toolkits
• 7.2.1 Few Off the Shelf Systems,
• 7.2.2 Lots of Toolkits
• 7.2.3 Toolkits for Various Levels
• 7.3 System Styles
• 7.4 Example Systems

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7.1 VR Software Features

• Importing models
• Libraries
• Level of detail (LOD)
• Object Position and Orientation
• Constraints
• Articulated features
• Animation
• Collision detection

• Parallel worlds
• Light sources
• Event handling
• Audio
• Control language
• Sensors/Tracking Device Support
• Stereo viewing

114
7.2 Complete vs Toolkits

• 7.2.1 Off the Shelf Systems,
• 7.2.2 Toolkits

115
7.2.1 Off the Shelf Systems

• Targeted at specific application markets
• Psychological testing and rehabilitation
• Medical Training Simulators
• Product Design (integrated with CAD/CAM)

116
7.2.2 Toolkits

• Benefits of Toolkits
• Flexibility of Device Interfaces
• Complexity of Development
• Toolkits for Various Levels
• 3d Graphics
• Audio
• Haptics
• Device Interface and Interaction
• Integration of different kits is an issue
• Need a standard component framework

117
7.3 System Styles

• Open Source
• Proprietary
• Web targeted
• Marketing Worlds (VRML, etc)
• E-Commerce Objects
• Community Worlds
• High End Systems
• Systems Integrators

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7.4 Example Systems

• Alice
• CDS
• Centric Software
• Crystal Space
• CyberToolbox
• DirectX
• DIVE
• Unigraphics/EAI Sense 8
• Eon Reality
• MetaVR
• Gismo3d
• Java3d
• Massive

• Meme
• MR Toolkit
• Multigen-Paradigm
• Open GL
• Blaxxun
• Performer
• R3Vis
• Renderware
• SVE
• VisKit
• Vivids
• VRML tools
• Vtree

See http//vr.isdale.com/AuthoringTools.html
119
8 Applications

• 8.1 Entertainment
• 8.2 Education/Training
• 8.3 Research
• 8.4 Design/Development
• 8.5 Medical
• 8.6 Marketing
• 8.7 Visualization

120
8.1 Entertainment

• Location Based Systems
• Arcade Games
• PC and Gamebox

121
8.2 Education/Training

• Vehicle Training
• Maintenance Training
• Medical Training
• Patient Education
• Situational Training
• Mission Rehearsal
• Virtual Heritage - History
• Hazardous Operations
• Science Math Education

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8.3 Research

• Geoscience
• Psychology
• Perception
• VR research

123
8.4 Design/Development

• Prototyping
• Product Design reviews
• Architectural review/presentation

124
8.5 Medical

• Training
• Psychological Assessment
• Perceptual Assessment
• Rehabilitation (psychological and physical)

125
8.6 Marketing

• Loss Leader Attractions
• Product Awareness
• Interactive Catalog

126
8.7 Visualization

• Scientific Visualization
• Display of scientific or engineering data for
  exploration and comprehension
• Geological exploration (oil, gas, minerals)
• Information Visualization
• Abstract data displayed geometrically for
  exploration and comprehension

127
9 Resources

• See web site for more details and live links
  http//vr.isdale.com/vetutorial
• 9.1 Books
• 9.2 Magazines
• 9.3 Societies
• 9.4 Conferences
• 9.5 Web Sites

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9.1 Books

• Several to appear in 2001 including "Handbook of
  Virtual Environments"
• John Vince, "Essential Virtual Reality"
• Singhal and Zyda. "Networked Virtual
  Environments"
• Lots of older titles and web centric ones

129
9.2 Magazines

• Game Developer
• VRNews
• Real Time Graphic News
• Computer Graphics World
• Advanced Imaging
• Presence Journal, presence lite
• VR Psychology

130
9.3 Societies

• ACM SIGGRAPH
• ACM SIGCHI
• ACM SIGMM
• IEEE Computer CGA magazine
• SPIE
• HFS

131
9.4 Conferences

• IEEE VR
• ACM Siggraph
• Lots of workshops and sections of other
  conferences

132
9.5 Web Sites

• Tutorials and University Courses
• VR Information Sites
• Topic Specific Information Sites
• Shared Worlds
• Vendors