Geog 463: GIS Workshop

May 22, 2006

Virtual Reality and GIS

Outlines

1. Defining virtual reality (VR)

2. Technologies for VR

3. VR, Geography, and GIS

4. Applications of VR in GIS

1. Defining virtual reality

Virtual Reality for Entertainment

Virtual Reality based Training for driver, pilot, and astronauts

The Matrix is the Movie about VR

• Have you ever thought about ...?– ‘I wish I could experience the environment as

if I were there without having to be there’– Conventional 2D map does not offer a ‘real’

sense of being there

Learning Geography using VR

• Virtual terrain– http://www.truflite.com/images/MonumentValley.mpg

• Virtual cities– http://www.ust.ucla.edu/ustweb/Projects/PROJECTS/videos/FirstStreetW_exist.wmv

Google Earth

Google moves into virtual worlds

• … “Consumers could fly into the virtual New York, go shopping in a virtual Times Square, get past the velvet rope at a virtual Studio 54 and chat with an avatar dressed as Andy Warhol. They could plan their next trip to the real New York in meticulous detail, become a detective in a Gotham noir, browse an apartment for sale, or jump into a taxi and play a driving game” … - Chris Taylor

From CNNMoney May 12, 2006

• If you are engaged with a representation to the point where your body is responding voluntarily to it as though it were the real world, then you are probably dealing with virtual reality

• Degree of engagement (or immersion)

• Any given set of data can be converted to many possible pictures. Each such transformation may be said to represent some facet of the data, which one really wants to examine as if it were a geological specimen, turning it over in the hand, looking from many points of view, touching and scratching - Tobler, 1979: 105

Compare how much these are worth, respectively

• It is said that a picture is worth a thousand word; how about these?

• Digital picture

• 3D digital picture

• Interactive 3D digital picture

Let us consider different ways to represent the Earth’s topography

• Remotely sensed image

• 2D contour map (e.g. topographic map)

• 3D perspective map (e.g. block diagram)

• Fly-through 3D perspective map

Representing urban environment…

• Remotely sensed image

• 2D map

• 3D built form

• Walk-through the urban environment

• VR can be seen as the uppermost level in a hierarchy that starts with the traditional two-dimensional map

Static 2D

Static 2.5D

Dynamic/Dynamic/interactive interactive 2.5D/3D 2.5D/3D

Presenting known fact …

• The process of glacier movement in geological time

Dynamic/interactive 3D of this map

Simulating unknown event …

• Effects of sea level rising

• VR constructs the artificial environment, whether it’s past, present, or future in a way that it feels like real

• What would be advantage of constructing the artificial environment?

• Advantage of creating the artificial world would be that you can manipulate the world unlike the real world– Assessing the visual impact of different planning

schemes and on enabling a group of planners to communicate through the number of applications

Characterizing VR

• Immersion– Offers realistic view of the phenomenon

• High dimensionality– 3D, and time

• Dynamics– Movement of objects, temporal elements

• High interactivity– User can control and manipulate objects

• Feeding sensory input to the user– Utilize multiple human sensory perceptions

Motivations for VR

• “The non-scientific audience … wants abstraction minimized, information content maximized… with the whole package digestible and non-threatening. This suggests the use of a visual realism approach that shows information…” – Ian Bishop (1994)

• VR can be seen as an effort to visualize and interact with the data through a very intuitive interface

Potentials for VR

• Advances in data capture technologies– Satellite image draped over DEM– DEM is collected directly from LiDAR– GPS allows us to collect in ubiquitous manner

• Increasing computing power and data storage– 3D graphic is widespread– Large data set can be processed quickly– Price of data storage is rapidly decreasing

What is virtual reality?

• An artificial environment created with computer hardware and software and presented to the user in such a way that it appears and feels like a real environment

• 3-D computer-based simulation of a real or imagined environment that users are able to navigate through and interact with

What is cyberspace?

• A metaphor for describing the non-physical terrain created computer systems. Online systems create a cyberspace within which people can communicate one another via e-mail, do research, or simply window shop

• In its extreme form, called virtual reality, users are presented with visual, auditory, and even tactile feedback that makes cyberspace feel real

Discussion questions

• How is VR related to cyberspace?

• How is VR related to 3D representation?

• How is VR different from animated map?

• How is VR different from multimedia?

• VR is a specialized (more immersive) form of cyberspace– Construction of artificial world

• VR utilizes 3D representation to offer high degree of realism– Multidimensionality

• VR is different from animated map in that it offers high level of user interaction– Interactivity

• Multimedia is not necessarily based on multidimensionality (3D or 4D)

2. Technologies for VR

Technologies for creating VR

• The technology for creating VR can be broken down into three parts:

• Display– CRT display

• Hardware controls– mouse and keyboard as controls

• GUI– Microsoft Windows as the interface

Five basic forms of display technologies

• Viewed without special devices (e.g. eyeglasses)– Desktop display– Wall-size display

• Viewed with special devices– Head-mounted display (HMD)– Room-format (e.g. CAVE)– Table-format display (e.g. immersaDesk)

Viewed without special display

• Desktop display: the most common approach for depicting VR

• Wall-size display: Covers a large portion of a wall by tiling images created by multiple projectors

Head-mounted display (HMD)

• Helmet-like device placed on the user’s head that shields the real world view and provides images of the VR to each eye

• Sophisticated HMD enables a stereoscopic view

Room-format displays

• Provides a room size view of VR by projecting images onto three walls and the floor (e.g. CAVE)

Table-format display

• VR is projected onto a single screen that is tilted at a 45 degree angle (e.g. ImmersaDesk)

3. VR, Geography, and GIS

Geographer’s knowledge- Forms of representations -

• Geographers should have understanding of the diversity of forms of representations of the human and physical worlds

From Kraak 2002

Plan-view

• The plan view is the conventional two-dimensional map interface

• The user can manipulate objects as symbols through GUI

Model-view

• In the model view, the data are presented as a simple and symbolic perspective in 2.5 dimensions with a bird’s eye view

• Navigation is by ‘fly-through’

World-view

• Immersive view of a virtual world• The user within the model• Realistic impression of the environment • Navigation is by “walk-through”

Two kinds of mappable data in VR

• Tangible data– The built environment– Topography

• Non-tangible data– Physical

• rainfall

– Socioeconomic• Population density

• Tangible data

• Non-tangible data

Well-developed

Rarely developed

Two kinds of functionalities in VR

• Constructing “No longer” environment– Virtual archeology– Presenting glacier movement

• Constructing “Not yet” environment– Simulation of future events (e.g. rise of sea

level)– Urban development project

Discussion questions

• What do you think VR can offer GIS or cartography?

• How is VR distinct from traditional cartography?

VR for GIS (subject view)

• VR and geographic data– VR relates to the multidimensional nature of

geographic data such as the urban environment, geological structures and geomorphological process

• VR for data representation– VR offers multiple representation in GIS (scale,

purpose)

• VR for user interface– VR offers intuitive user interface (query, viewpoint)

VR for GIS (functional view)

• High level of spatial cognition– VR offers the viewer a set of stimuli of the ‘real three-

dimensional world’ –

• High level of interactivity – User can navigate and manipulate the virtual world

• High level of engagement– The interactive and dynamic nature of VR can

stimulate the user’s engagement and understanding of the real world.

– Implication for public participation GIS (PPGIS)

VR in cartography view

VR for cartography

• 3D shapes and volumes• Other dimensions – time• Description of simulations of motion and

behavior – dynamics• User interaction• Multi-user worlds• Other environmental variable: lighting, fog• Alternative viewpoints – both user controlled and

predefined• The cartographer therefore have a whole

language to use in modeling spatial data…”

VR for cartography

• Making data representation close to reality

Advances in data capture technology

Real world

Close to reality

Conventional 2D map

Image map

Virtual world

3D graphics

High computing

User interface design

How is VR distinct from traditional cartography?

• The difference between VR and traditional cartography lies in the relationship between representation and user

• VR facilitates the transformation between map and user

map

user

map

user

Map

user

Traditional cartography Virtual Reality

Geographical Environment

RecognizedGeographicInformation

Representation

User

Geographical Environment

RecognizedGeographicInformation

Representation

User

Geographical Environment

RecognizedGeographicInformation

Representation

User

Geographical Environment

RecognizedGeographicInformation

Representation

User

a) b) c) d)

Virtual Reality?

From Bodile et al 2002

4. Applications of VR in GIS

Virtual Cities: demo

Virtual Cities• Forms

– Takes the form of highly detailed visual representation of buildings (and related structures) within the city

• Functions (in the order of degree of development)

– Property development project – most common– Assist citizens being involved in planning process– Assist researchers or citizens enhancing their understanding urban

process (simulation) – future development

• Barriers – Lack of focus on urban process– Lack of available data

• Listing of virtual cities– http://www.casa.ucl.ac.uk/3dcities/table_all.htm

Virtual Field Course: demo

• http://www.geog.le.ac.uk/vfc/education/vipsSoftware.html

• Users to explore the 3-D character of the natural landscape where fieldwork is going to be undertaken or has already been done (e.g. traVelleR)

• Users can plan routes for use with GPS receivers and plot them on returning from the field (e.g. panoraMap)

VR for education

• VR help students understand phenomena that cannot be directly experienced

• VR increase students’ engagement in learning tasks

• VR enable rescaling objects and process in time and space (e.g. a daily tidal cycle can be compressed to five seconds)

• VR allows students to make errors that might be disastrous in the real world (e.g. experiments in fighting forest fires)

Digital Earth: quote from Al Gore (1998)- Your children’s magic carpet ride -

• Imagine… a young children going to a Digital Earth exhibit at a local museum. After donning a HMD, she sees Earth as it appears from space. Using a data glove, she zooms in, using higher and higher levels of resolution, to see continents, then regions, countries, cities, and finally individual houses, trees, and other natural and man-made objects. Having found an area of the planet she is interested in exploring, she takes the equivalent of a “magic carpet ride” through a 3-D visualization of the terrain… Using the systems’ voice recognition capabilities, she is able to request information on land cover, distribution of plant and animal species, and so on… she is not limited to moving through space, but can also travel through time. After taking a virtual field-trip to Paris to visit the Louvre, she moves backward in time to learn about French history…

From http://www.digitalearth.gov

Digital Earth

• Vision of full-fledged digital representation of multiresolution space, time, and attribute (i.e. 4D)

Realizing the vision of Digital Earth is underway

Google Earth is one realized form of Digital Earth

References

• Bishop, 1994, The role of visual realism in communcating and understanding spatial change an dprocess, in Visualization in Geographical Information Systems, edited by Hearnshaw and Unwin

• Taylor, 1996, GISCC Unit 131, NCGIA• Kraak, 2002, chapter in Virtual Reality in Geography

edited by Fisher and Unwin• Brodile et al, 2002, chapter in Virtual Reality in

Geography edited by Fisher and Unwin• Slocum et al, 2005, Thematic Cartography and

Geographic Visualization• Tobler WR, 1979, A transformational view of

cartography. The American Cartographer, 62:101-6