1. 3D Object Retrieval Client-Server Project
Electrical Engineering Software Lab - Technion
3D Object Retrieval Client-Server Project
Spring semester 2001/02
Developers: Iddo Simhon
Omer Boker
Supervisor: George Leifman

2. 3D Object Retrieval Project – Spring semester 2001/02
Project Overview

3. Project Definition 3D objects retrieval by several algorithms.
The design enables addition of more algorithms in the future, open data-base.
The project is built as client-server system, each operates as a separate application.
The client is a Java application, based on Java 3D technology.
The server is a multi-threaded C++ application, and includes the 3D algorithms.

4. Project Features
Comparing a 3D object versus a bank of objects, and returning the 50 most similar objects, by a selected object comparison algorithm.
Fetching icons from the server by the above compare or by name/first letters or just the first 50 objects for a start.
Presentation of selected 3D objects using Java 3D.
Upload additional objects files to the server.
Download selected objects from the server.
Distributed system that enables many clients to work with the server.
Enabling the client to run on any platform, requiring minimum resources.

5. Project Educational Benefits
Java and C++ programming languages.
Object-Oriented design and programming.
Swing programming for Graphical User Interface.
Java 3D technology.
TCP/IP programming – Java Networking, Windows Sockets and the integration between them.
Windows Programming.
Application development in multi-threaded environment.
Experience in large-scaled software system development.
An idea about 3D Objects comparing algorithms.

6. The Client-Server and Multi-Threading Model
3D Object Retrieval Project – Spring semester 2001/02
The Client-Server and Multi-Threading Model

7. Main Properties
The Client is Java application that includes GUI and 3D representation component.
The server is C++ multi-threading application that includes 3D algorithms and database of objects and icons files.
The two applications communicate by TCP/IP, using sockets.
The server includes a ‘listening thread’, for acceptance of clients requests.
For each client request, the server creates a new thread to handle the request. This thread exists after finishing its job.

8. Main Properties – Cont.
This Client-Server application is State-Less. It works like the WWW. Each client’s request is handled separately.
The server knows nothing about the clients, and each connection is opened for a specific action, and closed immediately after finishing that action.
TCP/IP: Since the TCP/IP connects between two different languages, all the communication is done by bytes. The communication is harder to implement, since its impossible to use socket methods that transmit/receive other data types.

9. Client-Server Sockets Presentation
Client A
Client Socket
Server
Handling Socket
Listening Socket
Client B
Client Socket
Handling Socket
Handling Socket
Client C
Client Socket

10. Server Flow Chart Request from Client Listening Thread Upload/Download
Respond Thread
Upload/Download
Get 3D file
Search
Get Icons
Get/Put .off file. When uploading, the server creates also .obj and .gif files, and updates the databases.
Send to the client 3D shape file for presentation.
Compare given shape vs. the shapes DB, using one of the comparing algorithms. Send to the client most similar icons.
Send to the client icons, by a given string, or first 500 icons.

11. Searching the data base for the closest 50 shapes to a selected shape
Uploading or downloading a shape to/from the data base
Client GUI
Showing the shape using Java 3D
Bringing images from the data-base by name/first letters or first 50

12. Shapes Examples Shapes can be rotated by moving the mouse on the shape
When rotating a shape, the shades and light on it are changing

13. Presenting Objects by Java 3D
3D Object Retrieval Project – Spring semester 2001/02
Presenting Objects by Java 3D

14. Java 3D Scene Structure Virtual Universe Locale Object
Branch Group Nodes BG BG
Behavior Node
Transform Group Nodes T T
Shape3D Node
View Platform Object
Appearance
Geometry

15. 3D Object Retrieval Project – Spring semester 2001/02
The End