BaseSoundGenerator.java

/*
  BaseSoundGenerator.java

  (c) 2013 Ed Swartz

  All rights reserved. This program and the accompanying materials
  are made available under the terms of the Eclipse Public License v1.0
  which accompanies this distribution, and is available at
  http://www.eclipse.org/legal/epl-v10.html
 */
package v9t9.audio.sound;

import java.util.ArrayList;
import java.util.List;

import v9t9.common.client.ISoundHandler;
import v9t9.common.machine.IMachine;
import v9t9.common.machine.IRegisterAccess;
import v9t9.common.sound.ISoundGenerator;
import ejs.base.sound.ISoundOutput;
import ejs.base.sound.ISoundVoice;

/**
 * @author ejs
 *
 */
public abstract class BaseSoundGenerator implements ISoundGenerator, IRegisterAccess.IRegisterWriteListener {

	private ISoundVoice[] soundVoices;
	protected ISoundHandler soundHandler;
	protected int active;
	protected final List<ISoundVoice> soundVoicesList = new ArrayList<ISoundVoice>();

	private int lastUpdatedPos;

	private IMachine machine;

	/**
	 * @param machine 
	 * @param name 
	 * 
	 */
	public BaseSoundGenerator(IMachine machine) {
		this.machine = machine;
	}
	
	/**
	 * @return the machine
	 */
	public IMachine getMachine() {
		return machine;
	}

	public ISoundVoice[] getSoundVoices() {
		if (soundVoices == null || soundVoices.length != soundVoicesList.size()) {
			soundVoices = soundVoicesList.toArray(new ISoundVoice[soundVoicesList.size()]);
		}
		return soundVoices;
	}


	/* (non-Javadoc)
	 * @see v9t9.common.sound.ISoundGenerator#generate(int, int)
	 */
	@Override
	public void generate(ISoundOutput output, int pos, int total) {
		int totalCount = pos;
		
		int framesPerTick = output.getSamples((1000 + machine.getTicksPerSec() - 1) / machine.getTicksPerSec());

		long ticksPos = (long) (pos * framesPerTick * getSoundFormat().getChannels() );
		int currentPos = (int) ((ticksPos + total - 1 ) / total);
		if (currentPos < 0)
			currentPos = 0;
		if (currentPos > framesPerTick)
			currentPos = framesPerTick;
		updateSoundGenerator(output, lastUpdatedPos, currentPos, totalCount);
		lastUpdatedPos = currentPos;
	}

	protected void updateSoundGenerator(ISoundOutput output, int from, int to, int totalCount) {
		if (from >= to)
			return;
	
		ISoundVoice[] vs = getSoundVoices();
		output.generate(vs, to - from);
	}
	
	/* (non-Javadoc)
	 * @see v9t9.common.sound.ISoundGenerator#flushAudio(ejs.base.sound.ISoundOutput, int, int)
	 */
	@Override
	public void flushAudio(ISoundOutput output, int pos, int total) {
		if (output != null && total > 0) {
			int framesPerTick = output.getSamples((1000 + machine.getTicksPerSec() - 1) / machine.getTicksPerSec());

			int totalSoundCount = (int) (((long) pos * (framesPerTick - lastUpdatedPos + total - 1)) / total);
			updateSoundGenerator(output, lastUpdatedPos, framesPerTick, totalSoundCount);
			lastUpdatedPos = 0;
	
			ISoundVoice[] vs = getSoundVoices();
			output.flushAudio(vs, total);
		}		
	}
}