www.pudn.com > IntroductionTo3DGameEngineDesign.rar > Thinker.cs

using System; 
using System.Collections; 
using System.Threading; 
using System.Diagnostics; 
using System.Xml; 
using GameEngine; 
 
namespace GameAI 
{ 
	/// 
 
	/// Summary description for Thinker. 
	/// 
 
	public class Thinker : IDisposable 
	{ 
		#region delegates 
		public delegate void SensorMethod( Thinker the_thinker ); 
		public delegate void ActionMethod( Thinker the_thinker ); 
		#endregion 
 
		#region Attributes 
		private ArrayList     m_state_list = null; 
		private ArrayList     m_sensor_methods = null; 
		private AIState       m_current_state = null; 
		private SortedList    m_fact_list; 
		private Thread        m_think_thread; 
		private Model         m_model = null; 
		private bool          m_thread_active = true; 
 
		private static SortedList m_methods = new SortedList(); 
		#endregion 
 
		#region Properties 
		public Model Self { get { return m_model; } } 
		#endregion 
 
		public Thinker( Model model ) 
		{ 
			m_model = model; 
			m_state_list = new ArrayList(); 
			m_sensor_methods = new ArrayList(); 
			m_fact_list = new SortedList(); 
 
			m_methods = new SortedList(); 
 
			m_think_thread = new Thread(new ThreadStart(Execute)); 
			m_think_thread.IsBackground = true; 
			m_think_thread.Start(); 
		} 
 
		public static void AddAction( string action_name, ActionMethod method ) 
		{ 
			if ( !m_methods.Contains( action_name ) ) 
			{ 
				m_methods.Add(action_name, method); 
			} 
		} 
 
		public static ActionMethod GetAction( string action_name ) 
		{ 
			ActionMethod method = null; 
 
			if ( m_methods.Contains( action_name ) ) 
			{ 
				int index = m_methods.IndexOfKey( action_name ); 
				method = (ActionMethod)m_methods.GetByIndex(index); 
			} 
 
			return method; 
		} 
 
		public static string GetActionName( ActionMethod method ) 
		{ 
			string action_name = null; 
 
			if ( m_methods.Contains( method ) ) 
			{ 
				int index = m_methods.IndexOfValue( method ); 
				action_name = (string)m_methods.GetKey(index); 
			} 
 
			return action_name; 
		} 
 
		public void Execute() 
		{ 
			Debug.WriteLine("thinker thread started"); 
			while ( m_thread_active ) 
			{ 
				if ( m_current_state != null ) 
				{ 
					foreach ( SensorMethod method in m_sensor_methods ) 
					{ 
						method( this ); 
					} 
 
					m_current_state.DoActions( this ); 
					m_current_state = m_current_state.Think(); 
				} 
			} 
			Debug.WriteLine("thinker thread terminated"); 
 
		} 
 
		public void Dispose() 
		{ 
			m_thread_active = false; 
 
			while ( m_think_thread.IsAlive ) Thread.Sleep(1); 
		} 
 
		public AIState GetState( string name ) 
		{ 
			AIState the_state = null; 
 
			foreach ( AIState state in m_state_list ) 
			{ 
				if ( state.Name == name ) 
				{ 
					the_state = state; 
				} 
			} 
			return the_state; 
		} 
 
		public Fact GetFact( string name ) 
		{ 
			Fact the_fact = null; 
 
			if ( m_fact_list.Contains( name ) ) 
			{ 
				int index = m_fact_list.IndexOfKey( name ); 
				the_fact = (Fact)m_fact_list.GetByIndex(index); 
			} 
			else 
			{ 
				the_fact = new Fact(name); 
				the_fact.Value = 0.0f; 
				m_fact_list.Add( name, the_fact ); 
			} 
			return the_fact; 
		} 
 
		public void SetFact( string name, float value ) 
		{ 
			if ( m_fact_list.Contains( name ) ) 
			{ 
				int index = m_fact_list.IndexOfKey( name ); 
				Fact fact = (Fact)m_fact_list.GetByIndex(index); 
				fact.Value = value; 
			} 
			else 
			{ 
				Fact fact = new Fact(name); 
				fact.Value = value; 
				m_fact_list.Add( name, fact ); 
			} 
		} 
 
		public void AddSensorMethod( SensorMethod method ) 
		{ 
			m_sensor_methods.Add( method ); 
		} 
 
		public void AddState( AIState state ) 
		{ 
			m_state_list.Add( state ); 
		} 
 
		public void Write( string filename ) 
		{ 
			XmlTextWriter writer = new XmlTextWriter( filename, null ); 
 
			writer.WriteStartDocument(); 
			writer.WriteStartElement("Knowledge"); 
 
			//Use indentation for readability. 
			writer.Formatting = Formatting.Indented; 
			writer.Indentation = 4; 
         
			int num_facts = m_fact_list.Count; 
 
			for ( int i=0; i