Outline Introduction Related Work Problem Description and - - PDF document

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 1

為網路虛擬實境產生自動導覽路徑 Generating Customizable Guided Tours For Networked Virtual Environments

李蔡彥 甘連凱 蘇建富 Tsai-Yen Li, Lien-Kai Gan, and Chien-Fu Su 國立政治大學資訊科學系 Computer Science Department National Chengchi University, Taipei, Taiwan {li,s8204,s8237}@cs.nccu.edu.tw

Outline

Introduction Related Work Problem Description and Simplifications System Design Implementation Experimental Results Conclusion

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 2

Introduction

User Interface

2D display→ 3D display(VR)

User Habit

2D mouse vs. 3D environment

Smart system

automatically generate a customizable tour

path for user

Related Work

Guided Tours and VRML

1.0 static object 2.0 dynamic features

Motion Planning

generate a navigation plan for a robot

(moving object) in a known environment

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 3

Problem Description and Simplifications

The Planning Problem

generate collision-free path find an optimal sequence for traversing the given

locations

Simplifications

simplify geometric model of the moving object define the distance between two locations fixed environment

An example of skeleton for a freespace

skeleton Hallway Obstacle

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 4

System Design

3D-display Module Planning Module Integration Module

Web Browser VRML Plug-In Planning Applet EAI Applet

System Structure

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 5

System Design (1)

3D-display Module

a large model→several small models:

for performance

proximity sensors:

for automatic adjacent scenes transitions

external program:

for adding more sophisticated

programming logic

System Design (2)

Planning Module

skeleton visiting sequence smooth

Integration Module

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 6 ... Moving object Expanding CSpace

Cspace generation example

skeleton expand

Skeleton generation example

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 7

Implementation

VRML Models

modeling software: 3D studio add animation functions(e.g. ProximitySensor)

Path Planning

preprocessing of workspace path searching smoothong

Integration

through web browser(e.g. getAppletContext)

1 1 1 1 2 2 2 2 2 2 2

Breadth first search for neighbors

• bstacle

3 3 4 4 3 4 4

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 8

R e g i s t r a

• Path Searching

Set has_path and anim ation_enable Retrieving Position Registration ? Initialization Planning R equest Yes Succeed Fail

Planning Applet

Register Check has_path and anim ation_enable Get next configuration Set V R M L view point Initialization

EAI Applet

Yes No No

F l

• w

c h a r t s f

• r

t h e m a i n l

• p

s

• f

t h e p l a n n i n g a n d E A I a p p l e t s

Experimental Results

User Interface

3D display browser: WorldView 2D floor map layout

Performance

2D & 3D display time path length frame rate

甘連凱 2001/7/7 generating customizable guided tours for networked virtual environments 9

3D-Display Module Planning Module

VRML Browser 2D-Layout Map Command Panel Current Location

A snapshot of the system’s user interface

Conclusion

Browser Interface

3D display

Browser function

add some intelligent agent