- made the number of buffers a variable instead of hardcoding to 2

- made the buffer size and the #buffers specifiable from the command line
- added a sleep to the main "playstream" loop so as to not peg the CPU (from Ken Russel)


git-svn-id: file:///home/mbien/NetBeansProjects/JOGAMP/joal-sync/svn-server-sync-demos/joal-demos/trunk@59 235fdd13-0e8c-4fed-b5ee-0a390d04b286

2 files changed, 121 insertions, 25 deletions

diff --git a/src/java/demos/devmaster/lesson8/OggStreamer.java b/src/java/demos/devmaster/lesson8/OggStreamer.java
index 1f52973..a7b9b45 100644
--- a/src/java/demos/devmaster/lesson8/OggStreamer.java
+++ b/src/java/demos/devmaster/lesson8/OggStreamer.java
@@ -68,13 +68,23 @@ public class OggStreamer {
         }
     }
     
+    private static boolean debug = false;
+    private static int totalBytes = 0;
+
+    private static void debugMsg(String str) {
+	if (debug) System.err.println(str);
+    }
+
     private OggDecoder oggDecoder;
     
     // The size of a chunk from the stream that we want to read for each update.
-    private static int BUFFER_SIZE = 4096*8;
+    private static int BUFFER_SIZE = 4096*16;
+
+    // The number of buffers used in the audio pipeline
+    private static int NUM_BUFFERS = 2;
     
-    // Buffers hold sound data. There are two of them (front/back)
-    private int[] buffers = new int[2];
+    // Buffers hold sound data. There are two of them by default (front/back)
+    private int[] buffers = new int[NUM_BUFFERS];
     
     // Sources are points emitting sound.
     private int[] source = new int[1];
@@ -89,6 +99,8 @@ public class OggStreamer {
     
     private URL url;
 
+    private long sleepTime = 0;
+
     /** Creates a new instance of OggStreamer */
     public OggStreamer(URL url) {
 	this.url = url;
@@ -106,20 +118,35 @@ public class OggStreamer {
             return false;
         }
         
-        if (oggDecoder.numChannels() == 1)
+	int numChannels = oggDecoder.numChannels();
+	int numBytesPerSample = 2;
+
+        if (numChannels == 1)
 	    format = AL.AL_FORMAT_MONO16;
 	else
 	    format = AL.AL_FORMAT_STEREO16;
         
 	rate = oggDecoder.sampleRate();
 
-	System.err.println("format  = 0x" + Integer.toString(format, 16));
+	// A rough estimation of how much time in milliseconds we can sleep
+	// before checking to see if the queued buffers have been played
+	// (so that we dont peg the CPU by doing an active wait). We divide
+	// by 10 at the end to be safe...
+	// round it off to the nearest multiple of 10.
+	sleepTime = (long)(1000.0 * BUFFER_SIZE /
+			    numBytesPerSample / numChannels / rate / 10.0);
+	sleepTime = (sleepTime + 10)/10 * 10;
+
+	System.err.println("#Buffers: " + NUM_BUFFERS);
+	System.err.println("Buffer size: " + BUFFER_SIZE);
+	System.err.println("Format: 0x" + Integer.toString(format, 16));
+	System.err.println("Sleep time: " + sleepTime);
 
 	// TODO: I am not if this is the right way to fix the endian
 	// problems I am having... but this seems to fix it on Linux
 	oggDecoder.setSwap(true);
 
-        al.alGenBuffers(2, buffers, 0); check();
+        al.alGenBuffers(NUM_BUFFERS, buffers, 0); check();
         al.alGenSources(1, source, 0); check();
 
 	al.alSourcefv(source[0], AL.AL_POSITION , sourcePos, 0);
@@ -142,8 +169,9 @@ public class OggStreamer {
 	al.alSourceStop(source[0]);
 	empty();
 
-	al.alDeleteSources(1, source, 0); check();
-	al.alDeleteBuffers(2, buffers, 0); check();
+	for (int i = 0; i < NUM_BUFFERS; i++) {
+	    al.alDeleteSources(i, source, 0); check();
+	}
     }
 
     /**
@@ -153,13 +181,14 @@ public class OggStreamer {
 	if (playing())
 	    return true;
         
-	if (!stream(buffers[0]))
-	    return false;
-        
-	if(!stream(buffers[1]))
-	    return false;
+	debugMsg("playback(): stream all buffers");
+	for (int i = 0; i < NUM_BUFFERS; i++) {
+	    if (!stream(buffers[i]))
+		return false;
+	}
     
-	al.alSourceQueueBuffers(source[0], 2, buffers, 0);
+	debugMsg("playback(): queue all buffers & play source");
+	al.alSourceQueueBuffers(source[0], NUM_BUFFERS, buffers, 0);
 	al.alSourcePlay(source[0]);
     
         return true;
@@ -183,6 +212,7 @@ public class OggStreamer {
 	int[] processed = new int[1];
 	boolean active = true;
 
+	debugMsg("update()");
 	al.alGetSourcei(source[0], AL.AL_BUFFERS_PROCESSED, processed, 0);
 
 	while (processed[0] > 0)
@@ -190,9 +220,11 @@ public class OggStreamer {
 	    int[] buffer = new int[1];
 	    
 	    al.alSourceUnqueueBuffers(source[0], 1, buffer, 0); check();
+	    debugMsg("update(): buffer unqueued => " + buffer[0]);
 
 	    active = stream(buffer[0]);
 
+	    debugMsg("update(): buffer queued => " + buffer[0]);
 	    al.alSourceQueueBuffers(source[0], 1, buffer, 0); check();
 
 	    processed[0]--;
@@ -216,6 +248,9 @@ public class OggStreamer {
 	    return false;
 	}
 
+	totalBytes += size;
+	debugMsg("stream(): buffer data => " + buffer + " totalBytes:" + totalBytes);
+
 	ByteBuffer data = ByteBuffer.wrap(pcm, 0, size);
 	al.alBufferData(buffer, format, data, size, rate);
 	check();
@@ -265,6 +300,14 @@ public class OggStreamer {
             return false;
         
         while (update()) {
+	    // We will try sleeping for sometime so that we dont
+	    // peg the CPU...
+	    try {
+		Thread.sleep(sleepTime);
+	    } catch (Exception e) {
+		e.printStackTrace();
+	    }
+
             if (playing()) continue;
             
             if (!playback())
@@ -284,12 +327,23 @@ public class OggStreamer {
 	URL url;
 
         try {
-	    if (args.length == 0) {
-		url = OggStreamer.class.getClassLoader().getResource("demos/data/broken_glass.ogg");
-		(new OggStreamer(url)).playstream();
-	    }
-
+	    boolean played = false;
             for (int i = 0; i < args.length; i++) {
+		if ("-bs".equals(args[i])) {
+		    BUFFER_SIZE = Integer.valueOf(args[++i]).intValue();
+		    continue;
+		}
+
+		if ("-nb".equals(args[i])) {
+		    NUM_BUFFERS = Integer.valueOf(args[++i]).intValue();
+		    continue;
+		}
+
+		if ("-d".equals(args[i])) {
+		    debug = true;
+		    continue;
+		}
+
                 System.err.println("Playing Ogg stream : " + args[i]);
                 
                 url = ((new File(args[i])).exists()) ?
@@ -297,8 +351,15 @@ public class OggStreamer {
                 
                 if ((new OggStreamer(url)).playstream()) continue;
                 
+		played = true;
                 System.err.println("ERROR!!");
             }
+
+	    if (!played) {
+		url = OggStreamer.class.getClassLoader().getResource("demos/data/broken_glass.ogg");
+		(new OggStreamer(url)).playstream();
+	    }
+
         } catch (Exception e) {
             e.printStackTrace();
         }
diff --git a/www/devmaster/lesson8.html b/www/devmaster/lesson8.html
index 4d68908..a091df1 100644
--- a/www/devmaster/lesson8.html
+++ b/www/devmaster/lesson8.html
@@ -135,7 +135,13 @@ tutorial. <var>OggStreamer</var> which is the main class doing most of the worki
 
 </p>
 
-<pre class="code">    // The size of a chunk from the stream that we want to read for each update.<br>    private static int BUFFER_SIZE = 4096*8;<br></pre>
+<pre class="code">
+    // The size of a chunk from the stream that we want to read for each update.
+    private static int BUFFER_SIZE = 4096*8;
+
+    // The number of buffers used in the audio pipeline
+    private static int NUM_BUFFERS = 2;
+</pre>
 
 
 
@@ -170,8 +176,13 @@ just yet. I believe my comments should give you an idea of what they're for.</p>
 
 
 
-<pre class="code">    // Buffers hold sound data. There are two of them (front/back)<br>    private int[] buffers = new int[2];<br>    <br>    // Sources are points emitting sound.<br>    private int[] source = new int[1];<br>    <br>    private int format;	// OpenAL data format<br>    private int rate;	// sample rate<br></pre>
-
+<pre class="code">
+    // Buffers hold sound data. There are two of them by default (front/back)
+    private int[] buffers = new int[NUM_BUFFERS];
+    
+    // Sources are points emitting sound.
+    private int[] source = new int[1];
+</pre>
 
 
 <p>First thing that I want to point out is that we have 2 buffers dedicated to 
@@ -197,7 +208,7 @@ enumerator based on how many channels are in the Ogg and then make a not of the
 
 
 
-<pre class="code">    public boolean open() {<br>	...<br><br>        al.alGenBuffers(2, buffers, 0); check();<br>        al.alGenSources(1, source, 0); check();<br><br>	al.alSourcefv(source[0], AL.AL_POSITION , sourcePos, 0);<br>	al.alSourcefv(source[0], AL.AL_VELOCITY , sourceVel, 0);<br>	al.alSourcefv(source[0], AL.AL_DIRECTION, sourceDir, 0);<br>        <br>        al.alSourcef(source[0], AL.AL_ROLLOFF_FACTOR,  0.0f    );<br>        al.alSourcei(source[0], AL.AL_SOURCE_RELATIVE, AL.AL_TRUE);<br><br>	...<br>    }<br></pre>
+<pre class="code">    public boolean open() {<br>	...<br><br>        al.alGenBuffers(NUM_BUFFERS, buffers, 0); check();<br>        al.alGenSources(1, source, 0); check();<br><br>	al.alSourcefv(source[0], AL.AL_POSITION , sourcePos, 0);<br>	al.alSourcefv(source[0], AL.AL_VELOCITY , sourceVel, 0);<br>	al.alSourcefv(source[0], AL.AL_DIRECTION, sourceDir, 0);<br>        <br>        al.alSourcef(source[0], AL.AL_ROLLOFF_FACTOR,  0.0f    );<br>        al.alSourcei(source[0], AL.AL_SOURCE_RELATIVE, AL.AL_TRUE);<br><br>	...<br>    }<br></pre>
 
 
 
@@ -211,7 +222,16 @@ will still hear it. The same idea applies to source relativity.</p>
 
 
 
-<pre class="code">    public void release() {<br>	al.alSourceStop(source[0]);<br>	empty();<br><br>	al.alDeleteSources(1, source, 0); check();<br>	al.alDeleteBuffers(2, buffers, 0); check();<br>    }<br></pre>
+<pre class="code">
+    public void release() {
+	al.alSourceStop(source[0]);
+	empty();
+
+	for (int i = 0; i < NUM_BUFFERS; i++) {
+	    al.alDeleteSources(i, source, 0); check();
+	}
+    }
+</pre>
 
 
 <p>We can clean up after ourselves using this. We stop the source, empty out any 
@@ -219,7 +239,22 @@ buffers that are still in the queue, and destroy our objects.
 
 </p>
 
-<pre class="code">    public boolean playback() {<br>	if (playing())<br>	    return true;<br>        <br>	if (!stream(buffers[0]))<br>	    return false;<br>        <br>	if(!stream(buffers[1]))<br>	    return false;<br>    <br>	al.alSourceQueueBuffers(source[0], 2, buffers, 0);<br>	al.alSourcePlay(source[0]);<br>    <br>        return true;<br>    }<br></pre>
+<pre class="code">
+    public boolean playback() {
+	if (playing())
+	    return true;
+        
+	for (int i = 0; i < NUM_BUFFERS; i++) {
+	    if (!stream(buffers[i]))
+		return false;
+	}
+    
+	al.alSourceQueueBuffers(source[0], NUM_BUFFERS, buffers, 0);
+	al.alSourcePlay(source[0]);
+    
+        return true;
+    }
+</pre>