SilentAudioStake.java

/*
 *  SilentAudioStake.java
 *  Eisenkraut
 *
 *  Copyright (c) 2004-2016 Hanns Holger Rutz. All rights reserved.
 *
 *  This software is published under the GNU General Public License v3+
 *
 *
 *	For further information, please contact Hanns Holger Rutz at
 *	contact@sciss.de
 */

package de.sciss.eisenkraut.io;

import java.io.IOException;

import de.sciss.io.CacheManager;
import de.sciss.io.InterleavedStreamFile;
import de.sciss.io.Span;
import de.sciss.jcollider.Buffer;
import de.sciss.net.OSCBundle;
import de.sciss.timebased.Stake;

/**
 *	A fake silent audio stake that occupies no disk space.
 *	Thanks to scsynth's /b_fill command, this works harmonically
 *	with the supercollider player.
 */
public class SilentAudioStake extends AudioStake {

	private final int numChannels;

	protected SilentAudioStake(Span span, int numChannels) {
		super(span);

		this.numChannels = numChannels;
	}

	public void close()
			throws IOException {
		// well ...
	}

	public void cleanUp() {
		// well ...
	}

	public Stake duplicate()
	{
		return new SilentAudioStake( span, numChannels );
	}

	public Stake replaceStart( long newStart )
	{
		return new SilentAudioStake( span.replaceStart( newStart ), numChannels );
	}
	
	public Stake replaceStop( long newStop )
	{
		return new SilentAudioStake( span.replaceStop( newStop ), numChannels );
	}
	
	public Stake shiftVirtual( long delta )
	{
		return new SilentAudioStake( span.shift( delta ), numChannels );
	}
		
	public int readFrames( float[][] data, int dataOffset, Span readSpan )
	throws IOException
	{
		final int	len		= (int) readSpan.getLength();
		final int	stop	= dataOffset + len;
		float[]		temp;
		
		for( int i = 0; i < numChannels; i++ ) {
			temp = data[ i ];
			if( temp == null ) continue;
			for( int j = dataOffset; j < stop; j++ ) {
				temp[ j ] = 0.0f;
			}
		}
		
		return len;
	}
	
	public int writeFrames( float[][] data, int dataOffset, Span writeSpan )
	throws IOException
	{
		throw new IOException( "Not allowed" );
	}
	
	public long copyFrames( InterleavedStreamFile target, Span readSpan )
	throws IOException
	{
		final long		len		= readSpan.getLength();
		final int		bufLen	= (int) Math.min( 8192, readSpan.getLength() );
		final float[]	empty	= new float[ bufLen ];
		final float[][]	buf		= new float[ numChannels ][];
		int				chunkLen;
		
		for( int i = 0; i < buf.length; i++ ) {
			buf[ i ] = empty;
		}
		
		for( long framesWritten = 0; framesWritten < len; ) {
			chunkLen	= (int) Math.min( len - framesWritten, bufLen );
			target.writeFrames( buf, 0, chunkLen );
			framesWritten += chunkLen;
		}
		return len;
	}
	
	public int getChannelNum()
	{
		return numChannels;
	}

	public void flush()
			throws IOException {
		 /* empty */
	}

	public void addToCache(CacheManager cm) {
		 /* empty */
	}

	public void addBufferReadMessages(OSCBundle bndl, Span s, Buffer[] bufs, int bufOff) {
		final int len = (int) s.getLength();
		if (len == 0) return;

		for (Buffer buf : bufs) {
			bndl.addPacket(buf.fillMsg(
					bufOff * buf.getNumChannels(), len * buf.getNumChannels(), 0.0f));
		}
	}

	public void debugDump() {
		super.debugDumpBasics();
		System.err.println("  (silent)");
	}
}