SeGaCH Workshop, VAST 2008

1SeGaCH 2008 – VAST Symposium

An algorithm to show monuments in virtual words for cultural heritage

ELIOS Lab

Riccardo BertaELIOS Lab, DIBE, University of Genoa

[email protected]


Presentation Outline

Research context: Travel in Europe project

Trade-off: photorealism vs model simplicity

Solutions: aarchitectonic-style Likelihood principle

Monument problem: very complex shapes

Standard billboard technique

Dynamic billboard applied to monuments

Example

Conclusions


Travel in Europe (TiE) project

Travel in Europe (TiE): European project co-funded by Culture 2000 programme

Implement an innovative mean to promote and divulgate the European heritage

The main target audience: high-school students aged 14 to 18

An easy-to-access online environmentUsers will live challenging and compelling game experiences by interacting with virtual representations of European heritage

The project exploits the concept of travelEngaging by itselfSupports geographic contextualization


TiE Vision

A player of TiE moves in a 2D space representing the map of EuropeThe player visits some cities and regions that are reconstructed in 3DHe faces 2D trials (microGames: mGs) embedded in the 3D reconstructions to obtain scores

mGs will concern the local artistic heritage and will be contextualizedE.g. an art game concerning the Van Cleve’s “Adoration of

the Magi” picture will be played in the 3D reconstruction of the San Donato church in Genoa’s historical center, where the picture is conserved


2D Europe Map


3D world


Trade-off

Trade-offPhotorealismHighly impressiveCulturally correct and meaningful experience

– The player as a sort of art/history detective

Models’ weight and complexityAllow interactive real-time online exploration


POIs and RBAs

Point of Interests (PoI)High-detail, rigorous reconstructions of a buildingCathedral, theather, Renaissance palace

Random Building Areas (RBA)Dynamically built using a statistical template-based algorithmExploit a statistical description of the architectonic

parametersUse a limited set of textures that are instances of

architectonic features representative of that area (e.g windows, portals, etc.)


POIs


RBAs


Likelihood principle

Architectonic-style likelihood principleAllows users to live experiences similar to a real visit of a city limiting the effort in 3D modeling:Like in a real visit: a visitor perceives the

feeling of being in a precise place but usually does not perceive/remember the particulars of each distinct building


Monuments

A major problems: monumentsVery complex modeling task

Very important to realize a virtual model of a city


Billboard (or “sprite”) videogame technique

A 2D image integrated into a 3D scene

This 2D image always faces the viewer In other words: the billboard plane is always perpendicular to the view direction from the camera.

Billboarding is used to create an illusion Although it is 2D, it often represents a 3D object.Example: tree, foliage,etc..


Billboard videogame technique

Used for:“foliage replicator”

Trees

...

Example: Torque Game Engine Demo


Dynamic Billboard for Monuments

A modified billboard algorithm:

the billboard for monument is composed of several textures that are displayed at different viewing angles

This allows to see the monument from multiple angles, instead of it always looking the same, no matter from what angle you viewed it



Content collection:You can imagine the monument as if it were surrounded by a sphere, and the digital camera placed in N positions in the sphere equator

The camera lenses are directed towards the center of the sphere

It is necessary to provide for each monument N pictures taken with the camera’s line of sight perpendicular to the monuments and spaced equally on the equator line







Example from TiE prototype


Conclusions and Future Works

Project started in Nov 2006

User needs analysis performedStudents, teachers, art experts from 8 countries

Design deliverableGame engine, cultural environment mechanisms, MMORG architecture, trial games

Content Collection (semi-automatic)Rules for 3rd parties to provide maps and pictures from the cities to be implemented

Contents for the trial-games

Implementation has started, and we have a demo that include some cities

Education

SeGaCH Workshop, VAST 2008