Libsecondlife: Bots
Hyungwook Park
LSL vs. libsecondlife


Linden Script Language (LSL)

Programming language used by residents of Second Life

Controls the behavior of in-world objects and allows objects to interact with
the Second Life world

State-event driven scripting language, in the sense of a finite state machine
Libsecondlife (LibSL)

A software library to communicate with the servers that control the virtual
world of Second Life Function by manipulating avatars

Reverse engineering of SL network protocol

Used both to query the state of the world and to send uploads and
commands that will modify the state

Written in general purpose programming language (C#)
Bots in Second Life

What is the difference between Avatar and Bot?
http://www.youtube.com/watch?v=bcemyUuzCds&eurl=

Two types of bot


LSL based (prims)

Come in many shapes and sizes

Primarily server side code
LibSL based (avatars)

Function by manipulating avatars

Mixed computation from client and server

Network delay becomes an issue
Communication Network
Second Life
Libsecondlife
Function
Second Life
Server
Second Life
Server
Function
Visualization
Client
Centralized network topology
Daemon
Visualization
Client
Client-server model
LSL Bot

Prims with (motion) control
 Control is defined through LSL
 Integrated sensing (LSL sensors)
 Can interface with remote resources

http://www.youtube.com/watch?v=824TFPerXsQ

Tour Guide (Aesthetica)
LSL Bots: LSL Limitations

Language limitations

Emphasis on states and events
 No native arrays, only sequential list can be used
 Limited length for script (16KB)
 make it difficult to develop large, complex applications

Control limitations

Embedded in a prim, not in avatars
 Cannot log into the world more than one avatar
 Avatar cannot have the script, thus the prim has to be attached into the
avatar
LibSecondLife

Potential for complete avatar simulation


Reverse engineering of SL network protocol
Based on C#

All C# features are available

Much more flexible programming environment

Avatar control

Client-server interface
LibSecondLife (continue)

Disadvantages

Network traffic is subject to missed packets and limited by client
performance

Not robust (Beta version v0.3.2) and lack of documentation
 Combination with LSL will be one of possible solutions

Demos

http://www.youtube.com/watch?v=3TFGFtRizn0

http://www.youtube.com/watch?v=VaUNX00Uqc0
LibSL: Getting Started (1)

Prerequisites (For Windows)

C# compiler
 Visual Studio .NET 2005 (Windows)
 Visual Studio Express .NET (Windows, free)

Source code via SubVersion (SVN)*
 svn://openmetaverse.org/libsl/trunk

For more help:
 http://www.libsecondlife.org/wiki/Main_Page
 http://www.libsecondlife.org/wiki/Getting_Started
* Subversion (SVN) is a version control system. It is used to maintain current and
historical versions of files such as source code, web pages, and documentation.
LibSL: Getting Started (2)

Instructions

Create a folder named dev in C:\

In the dev folder, create a folder named libsecondlife.

Right click the libsecondlife folder, select SVN Checkout…

In the field for "URL of Repository", put
svn://opensecondlife.org/libsl/trunk

Files should start getting downloaded.
How to create a basic libSL bot

http://www.libsecondlife.org/wiki/Use_libSL_to_login_to_the_SL_grid
LibSL: Sample code (1)
using
using
using
using
System;
System.Collections.Generic;
System.Text;
libsecondlife;
namespace MyFirstBot
{
class MyFirstBot
{
public static SecondLife client = new SecondLife();
private static string first_name = "First";
private static string last_name = "Last";
private static string password = "password";
Include libsecondlife libraries
Define SecondLife client(s)
Add your bot’s name
Define a connected event
public static void Main()
{
client.Network.OnConnected += new NetworkManager.ConnectedCallback(Network_OnConnected);
if (client.Network.Login(first_name, last_name, password, "My First Bot", "Your name"))
Console.WriteLine("I logged into Second Life!");
else
Console.WriteLine("I couldn't log in);
}
Try to log in to the Grid
static void Network_OnConnected(object sender)
{
Console.WriteLine("I'm connected to the simulator");
client.Self.Chat("Hello World!", 0, ChatType.Normal);
Console.WriteLine("Now I am going to logout of SL.. Goodbye!");
client.Network.Logout();
}
When connected, send a message
}
}
After your message, logout
LibSL: Sample code (2)
using
using
using
using
System;
System.Collections.Generic;
System.Text;
libsecondlife;
string startLocation = NetworkManager.StartLocation("Second China", 179,165,31);
namespace MyFirstBot
{
if (client.Network.Login(first_name, last_name, password, "My First Bot", startLocation,
class MyFirstBot
{
public static SecondLife client = new SecondLife();
private static string first_name = "First";
private static string last_name = "Last";
private static string password = "password";
public static void Main()
{
client.Network.OnConnected += new NetworkManager.ConnectedCallback(Network_OnConnected);
if (client.Network.Login(first_name, last_name, password, "My First Bot", "Your name"))
Console.WriteLine("I logged into Second Life!");
else
Console.WriteLine("I couldn't log in);
}
static void Network_OnConnected(object sender)
{
Console.WriteLine("I'm connected to the simulator");
client.Self.Chat("Hello World!", 0, ChatType.Normal);
Console.WriteLine("Now I am going to logout of SL.. Goodbye!");
client.Network.Logout();
}
}
}
"Your name"))
LibSL: Framework

Most actions are defined within callbacks (events)

Network events
 OnConnected / OnDisconnected
 OnCurrentSimChanged

Client (Avatar) events
 OnInstantMessage
 OnChat
 OnTeleport

Object events
 OnNewAvatar / OnNewPrim
 OnObjectUpdated / OnObjectKilled
LibSL: Communication

Send an instant message


Say something



client.Self.InstantMessage(target, "Hello, World!");
client.Self.Chat("Hey There World", 0, ChatType.Normal);
Respond to instant message

client.Self.OnInstantMessage += new
AgentManager.InstantMessageCallback(Self_OnInstantMessage);

static void Self_OnInstantMessage(InstantMessage im, Simulator sim)
Respond to chat

client.Self.OnChat += new AgentManager.ChatCallback(Self_OnChat);

static void Self_OnChat(string message, ChatAudibleLevel audible, ChatType
type, ChatSourceType sourceType, string fromName, LLUUID id,
LLUUID ownerid, LLVector3 position)
LibSL: Movement


Teleport

client.Self.Teleport(“Second China", new LLVector3(128.0f, 128.0f, 50.0f));

client.Self.Teleport(new LLUUID("The-key-of-a-landmark"));

client.Self.OnTeleport += new AgentManager.TeleportCallback(Self_OnTeleport);

static void Self_OnTeleport(string message, AgentManager.TeleportStatus
status, AgentManager.TeleportFlags flags)

LookAt(LLVector3 location)
Walk


client.Self.AutopilotLocal(128, 128, 30);
http://www.libsecondlife.org/docs/
Animation

client.Self.AnimationStart(“UUID of animation”, true);
System.Threading.Thread.Sleep(5000);
client.Self.AnimationStop(“UUID of animation”, true);
Second China Demo

Questions?