samer@0: /*
samer@0:  *	Copyright (c) 2000, Samer Abdallah, King's College London.
samer@0:  *	All rights reserved.
samer@0:  *
samer@0:  *	This software is provided AS iS and WITHOUT ANY WARRANTY;
samer@0:  *	without even the implied warranty of MERCHANTABILITY or
samer@0:  *	FITNESS FOR A PARTICULAR PURPOSE.
samer@0:  */
samer@0: 
samer@0: package samer.tools;
samer@0: 
samer@0: import samer.core.*;
samer@0: import samer.core.util.*;
samer@0: import samer.core.types.*;
samer@0: import java.util.*;
samer@0: 
samer@0: /** frame rate regulator */
samer@0: 
samer@0: public class RThread extends Viewable implements Agent, Runnable
samer@0: {
samer@0: 	Task		task, termhook;
samer@0: 	Thread	thread;
samer@0: 	int			prio;
samer@0: 	boolean	running;
samer@0: 	int			numloops=0;
samer@0: 
samer@0: 	int			N=10, count;
samer@0: 	long		t0, elapsed, iterations;
samer@0: 	boolean	regulated=true;
samer@0: 	VDouble	target;			// target frame rate
samer@0: 	double		actual;			// actual frame rate
samer@0: 	long		period, wakeTime,nanos;
samer@0: 
samer@0: 	private volatile boolean paused=false;
samer@0: 	private volatile boolean kill=false;
samer@0: 
samer@0: 
samer@0: 	// .....Constructors................................
samer@0: 
samer@0: 	public RThread() { this(new NullTask()); }
samer@0: 	public RThread(Task r)
samer@0: 	{
samer@0: 		super("regulator");
samer@0: 
samer@0: 		Shell.push(node);
samer@0: 		target = new VDouble("target",50,0);
samer@0: 		regulated = Shell.getBoolean("regulated",regulated);
samer@0: 		setPriority(Shell.getDouble("thread.priority",-0.25));
samer@0: 		Shell.pop();
samer@0: 
samer@0: 		setN(actual=target.value);
samer@0: 		setPeriod();
samer@0: 		setAgent(this);
samer@0: 
samer@0: 		task=r; termhook=null;
samer@0: 		thread=new Thread(this);
samer@0: 		thread.setPriority(prio);
samer@0: 		running=false;
samer@0: 
samer@0: 		Shell.registerAgent(this);
samer@0: 		Shell.registerViewable(this);
samer@0: 	}
samer@0: 
samer@0: 	public Task onFinish(Task t) { Task old=termhook; termhook=t; return old; }
samer@0: 	public Viewer	getViewer() { return new UI(); }
samer@0: 
samer@0: 	public void dispose()
samer@0: 	{
samer@0: 		Shell.deregisterAgent(this);
samer@0: 		Shell.deregisterViewable(this);
samer@0: 		target.dispose();
samer@0: 		super.dispose();
samer@0: 	}
samer@0: 
samer@0: 	public Task getTask() { return task; }
samer@0: 	public void setTask(Task t) { task=t; }
samer@0: 	
samer@0: 	public class Kill extends Exception {}
samer@0: 
samer@0: 	public void interrupt() { thread.interrupt(); }
samer@0: 	public void join() {
samer@0: 		try { thread.join(); }
samer@0: 		catch (InterruptedException ex) {}
samer@0: 	}
samer@0: 
samer@0: 	public void start() { start(0); }
samer@0: 	public void start(int n)
samer@0: 	{
samer@0: 		paused=false; kill=false;
samer@0: 		numloops=n;
samer@0: 		reset();
samer@0: 		thread=new Thread(this);
samer@0: 		thread.setPriority(prio);
samer@0: 		thread.start();
samer@0: 	}
samer@0: 
samer@0: 	/**	<b>Important:</b> this method BLOCKS until the
samer@0: 	  *	thread co-operatively terminates, either naturally
samer@0: 	  *	or by not handling the InterruptedException that
samer@0: 	  *	will be thrown by the <code>checkpoint()</code> method
samer@0: 	  *	the next time it is called.
samer@0: 	  */
samer@0: 
samer@0: 	public void kill()
samer@0: 	{
samer@0: 		if (!thread.isAlive()) return;
samer@0: 
samer@0: 		synchronized (this) {
samer@0: 			kill=true;
samer@0: 			paused=true;
samer@0: 			thread.interrupt(); // this will interrupt sleep, wait etc
samer@0: 		}
samer@0: 		try { thread.join(5000); }
samer@0: 		catch (Exception ex) {
samer@0: 			Shell.trace("RThread.kill failed: "+ex);
samer@0: 		}
samer@0: 	}
samer@0: 
samer@0: 
samer@0: 	public void setPriority(double p)
samer@0: 	{
samer@0: 		Shell.trace("thread priority is "+p);
samer@0: 		if (p==0) { prio=Thread.NORM_PRIORITY; }
samer@0: 		else if (p>0) {
samer@0: 			prio=Thread.NORM_PRIORITY+(int)(p*(Thread.MAX_PRIORITY-Thread.NORM_PRIORITY));
samer@0: 		} else {
samer@0: 			prio=Thread.NORM_PRIORITY-(int)(p*(Thread.MIN_PRIORITY-Thread.NORM_PRIORITY));
samer@0: 		}
samer@0: 	}
samer@0: 
samer@0: 	public void pause() { paused=true; }
samer@0: 	public void unpause() {
samer@0: 		if (paused) synchronized (this) {
samer@0: 			paused=false; notifyAll();
samer@0: 		}
samer@0: 	}
samer@0: 
samer@0: 	/**	This method blocks if the thread has been paused
samer@0: 	  *	and throws an InterruptedException if the thread
samer@0: 	  *	has been killed.
samer@0: 	  */
samer@0: 
samer@0: 	public final void checkpoint() throws Kill
samer@0: 	{
samer@0: 		if (paused) synchronized (this) {
samer@0: 			Shell.trace("pausing");
samer@0: 			running=false; task.stopping();
samer@0: 			if (kill) throw new Kill();
samer@0: 			try { wait(); } catch (Exception ex) {}
samer@0: 			if (kill) throw new Kill();
samer@0: 			running=true; task.starting(); reset();
samer@0: 			Shell.trace("unpausing");
samer@0: 		}
samer@0: 	}
samer@0: 
samer@0: 	public void run()
samer@0: 	{
samer@0: 		try {
samer@0: 			Shell.trace("Regulator: init");
samer@0: 			task.starting();
samer@0: 			running=true;
samer@0: 
samer@0: 			try {
samer@0: 				if (numloops==0) {
samer@0: 					for (;;) {
samer@0: 						task.run();
samer@0: 						if (regulated) tick();
samer@0: 						//if (regulated) synchronized (this) { wait(); }
samer@0: 						if (++count>=N) { tock(); changed(); }
samer@0: 						checkpoint();
samer@0: 					}
samer@0: 				} else {
samer@0: 					int n=numloops;
samer@0: 					numloops=0;
samer@0: 					for (int i=0;i<n;i++) {
samer@0: 						task.run();
samer@0: 						if (regulated) tick();
samer@0: 						//if (regulated) synchronized (this) { wait(); }
samer@0: 						if (++count>=N) { tock(); changed(); }
samer@0: 						checkpoint();
samer@0: 					}
samer@0: 					task.stopping();
samer@0: 					tock(); changed();
samer@0: 				}
samer@0: 			}
samer@0: 			catch (Kill ex) { throw ex; }
samer@0: 			catch (Exception ex) { task.stopping(); throw ex; }
samer@0: 			finally {
samer@0: 				running=false;
samer@0: 				Shell.trace("Regulator: term");
samer@0: 				if (termhook!=null) {
samer@0: 					Shell.trace("running termination hook");
samer@0: 					try { termhook.run(); }
samer@0: 					catch (Exception ex) { ex.printStackTrace(); }
samer@0: 				}
samer@0: 			}
samer@0: 		}
samer@0: 		catch (Kill ex) {
samer@0: 			System.out.println("Regulator: thread killed");
samer@0: 		}
samer@0: 		catch (Exception ex) {
samer@0: 			System.out.println("Regulator: "+ex);
samer@0: 			ex.printStackTrace();
samer@0: 		}
samer@0: 	}
samer@0: 
samer@0: 	private final void tick() throws Exception {
samer@0: 		long now=System.currentTimeMillis();
samer@0: 		if (now<wakeTime) {
samer@0: 			Thread.sleep(wakeTime-now);
samer@0: 			wakeTime+=period;
samer@0: 		} else wakeTime=now+period;
samer@0: 	}
samer@0: 
samer@0: 	public double fps()				{ return actual; }
samer@0: 	public double elapsedTime() { return elapsed/1000.0; }
samer@0: 	public long iterations() 			{ return iterations; }
samer@0: 	public void setRate( double r) { target.value=r; target.changed(); }
samer@0: 	public void regulate() { regulated=true; setPeriod(); }
samer@0: 	public void deregulate() { regulated=false; }
samer@0: 
samer@0: 	private void setPeriod() {
samer@0: 		period=(long)(1000.0/target.value);
samer@0: 		// double T=(1000.0/target.value);
samer@0: 		// period = (long)T;
samer@0: 		// nanos = (long)(1000000.0*(T-period));
samer@0: 		// Shell.trace("period = "+period+"ms + "+nanos+"ns");
samer@0: 	}
samer@0: 
samer@0: 	public void reset()
samer@0: 	{
samer@0: 		setPeriod();
samer@0: 		count=0; setN(actual);
samer@0: 		t0=System.currentTimeMillis();
samer@0: 		wakeTime=t0+period;
samer@0: 	}
samer@0: 
samer@0: 
samer@0: 	public void tock()
samer@0: 	{
samer@0: 		long	t = System.currentTimeMillis();
samer@0: 		long	dt = t-t0;
samer@0: 
samer@0: 		elapsed+=dt;
samer@0: 		iterations+=count;
samer@0: 		actual = (1000.0*count)/dt;
samer@0: 		count = 0;	t0 = t;
samer@0: 		setN(actual); // try to count for 2 seconds
samer@0: 		setPeriod();
samer@0: 	}
samer@0: 
samer@0: 	private void setN(double rate)
samer@0: 	{
samer@0: 		// set the number of iterations to time
samer@0: 		// given a certain rate
samer@0: 		N=(int)(2*rate); 	// try to count for 2 seconds
samer@0: 		if (N==0) N=1;	// at least 1!
samer@0: 	}
samer@0: 
samer@0: 	public void getCommands(Agent.Registry r) {
samer@0: 		r.add("start").add("pause").add("kill").add("step");
samer@0: 		r.add("zero"); // do we want this one here?
samer@0: 	}
samer@0: 
samer@0: 	public void execute(String c, Environment env) throws Exception
samer@0: 	{
samer@0: 		if      (c.equals("start") || c.equals("resume")) { if (thread.isAlive()) unpause(); else start(); }
samer@0: 		else if (c.equals("stop") || c.equals("pause"))  pause();
samer@0: 		else if (c.equals("step")) {
samer@0: 			if (!running) {
samer@0: 				task.starting();
samer@0: 				task.run();
samer@0: 				task.stopping();
samer@0: 			} else {
samer@0: 				Shell.print("Cannot step while thread is running.");
samer@0: 			}
samer@0: 		} else if (c.equals("regulated")) {
samer@0: 			regulated = X._bool(env.datum(),!regulated);
samer@0: 			reset(); changed();
samer@0: 		} else if (c.equals("zero")) {
samer@0: 			tock();  elapsed=iterations=0; changed();
samer@0: 		} else if (c.equals("tock")) { tock(); changed(); }
samer@0: 		else if (c.equals("exit") || c.equals("kill")) {
samer@0: 			Shell.trace("killing thread...");
samer@0: 			kill();
samer@0: 			Shell.trace("thread killed.");
samer@0: 		}
samer@0: 	}
samer@0: 
samer@0: 	class UI extends BaseViewer
samer@0: 	{
samer@0: 		NumberViewer	actualRate=Shell.createNumberViewer("Actual rate",NumberViewer.TEXT);
samer@0: 		NumberViewer	elapsedTime=Shell.createNumberViewer("Elapsed time",NumberViewer.TEXT);
samer@0: 		NumberViewer	iterationCount=Shell.createNumberViewer("Iterations",NumberViewer.TEXT);
samer@0: 		Viewer			targetViewer;
samer@0: 		VBoolean		reg;
samer@0: 
samer@0: 		UI()
samer@0: 		{
samer@0: 			super(RThread.this);
samer@0: 			setLayout( new StackLayout(2));
samer@0: 			panel().setName(getLabel());
samer@0: 
samer@0: 			targetViewer = target.getViewer();
samer@0: 			reg = new VBoolean("regulated",regulated,0);
samer@0: 			reg.addObserver(this);
samer@0: 
samer@0: 			add( targetViewer.getComponent());
samer@0: 			add( actualRate.getComponent());
samer@0: 			add( elapsedTime.getComponent());
samer@0: 			add( iterationCount.getComponent());
samer@0: 			add( reg.getViewer().getComponent());
samer@0: 
samer@0: 			panel().add(Shell.createButtonsFor(RThread.this));
samer@0: 		}
samer@0: 
samer@0: 		public void attach() { targetViewer.attach(); super.attach(); }
samer@0: 		public void detach() {	targetViewer.detach(); super.detach(); }
samer@0: 
samer@0: 		public void update(Observable o, Object src)
samer@0: 		{
samer@0: 			if (reg==o && src!=this) {
samer@0: 				regulated = reg.value;	setPeriod();
samer@0: 			}
samer@0: 			if (reg.value!=regulated) {
samer@0: 				reg.value=regulated; reg.changed(this);
samer@0: 			}
samer@0: 
samer@0: 			actualRate.set((int)actual);
samer@0: 			elapsedTime.set((double)(elapsed/1000.0));
samer@0: 			iterationCount.set((int)(iterations));
samer@0: 			super.update(o,src);
samer@0: 		}
samer@0: 
samer@0: 	}
samer@0: }