Reverse.java

/*
 *  Reverse.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.render;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import de.sciss.io.Span;
import de.sciss.timebased.MarkerStake;
import de.sciss.timebased.Stake;

public class Reverse extends AbstractRenderPlugIn {

	private Span			prTotalSpan;
	private RenderConsumer	prConsumer;

	public int getMarkerPolicy()
	{
		return POLICY_MODIFY;
	}

	public int getUnselectedAudioPolicy()
	{
		return POLICY_MODIFY;
	}

	public boolean producerBegin( RenderSource source )
	throws IOException
	{
		// random read access not necessary any more since the consumer
		// automatically handles random write access!
//		source.context.setOption( RenderContext.KEY_PREFBLOCKSIZE, new Integer( BLOCKSIZE ));
//		source.context.setOption( RenderContext.KEY_RANDOMACCESS, this );
		prTotalSpan	= source.context.getTimeSpan();
		// request last block
//		prNextSpan	= new Span( Math.max( prTotalSpan.start, prTotalSpan.stop - BLOCKSIZE ), prTotalSpan.stop );
		prConsumer	= source.context.getConsumer();

		// flip markers at once
		if (source.validMarkers) {
			final int numMarkers = source.markers.getNumStakes();
			final List<Stake> collNew = new ArrayList<Stake>(numMarkers);
			MarkerStake m;
			for (int i = 0; i < numMarkers; i++) {
				m = (MarkerStake) source.markers.get(i, true);
				collNew.add(m.replaceStart(prTotalSpan.stop - m.pos + prTotalSpan.start));
			}
			source.markers.clear(this);
			source.markers.addAll(this, collNew);
		}
		
		return prConsumer.consumerBegin( source );
	}

	public boolean producerRender(RenderSource source)
			throws IOException {

		float temp;
		float[] chBuf;

		// reverse each block
		for (int ch = 0; ch < source.numAudioChannels; ch++) {
			if (!source.audioTrackMap[ch]) continue;
			chBuf = source.audioBlockBuf[ch];
			for (int i = source.audioBlockBufOff, j = i + source.audioBlockBufLen - 1; i < j; i++, j--) {
				temp = chBuf[i];
				chBuf[i] = chBuf[j];
				chBuf[j] = temp;
			}
		}

		// pseudo code:
		// blockStart --> totalStop - (blockStart - totalStart) - blockLen
		// blockStart --> totalStop + totalStart - blockStop
		// shift = totalStop + totalStart - blockStop - blockStart
		source.blockSpan = source.blockSpan.shift(prTotalSpan.stop + prTotalSpan.start - source.blockSpan.stop - source.blockSpan.start);

		return prConsumer.consumerRender(source);
	}

	public String getName()
	{
		return getResourceString( "plugInReverse" );
	}
	
	// ---------- RandomAccessRequester interface ----------
	
//	public Span getNextSpan()
//	{
//		return prNextSpan;
//	}
}