/*******************************************************************************
* Catroid: An on-device visual programming system for Android devices
* Copyright (C) 2010-2013 The Catrobat Team
* (<http://developer.catrobat.org/credits>)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* An additional term exception under section 7 of the GNU Affero
* General Public License, version 3, is available at
* http://www.catroid.org/catroid/licenseadditionalterm
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
******************************************************************************/
package org.catrobat.musicdroid.animation;
import android.content.Context;
import android.graphics.drawable.AnimationDrawable;
import android.util.Log;
import org.catrobat.musicdroid.R;
public class MetronomAnimation extends AnimationDrawable {
private int intervalTick;
private int intervalTock;
private int sign; // 1 or -1
private int numIterationsToOneMs;
public MetronomAnimation(Context context, double beatsPerMinute) {
new AnimationDrawable();
computeValues(beatsPerMinute);
addFrame(context.getResources().getDrawable(R.drawable.metronom_light_tick), intervalTick);
addFrame(context.getResources().getDrawable(R.drawable.metronom_light), getIntervalLength(0));
for (int i = 1; i <= 3; i++) {
addFrame(context.getResources().getDrawable(R.drawable.metronom_light_tock), intervalTick);
addFrame(context.getResources().getDrawable(R.drawable.metronom_light), getIntervalLength(i));
}
addFrame(context.getResources().getDrawable(R.drawable.metronom_light_tick), intervalTick);
addFrame(context.getResources().getDrawable(R.drawable.metronom_light), getIntervalLength(4));
for (int i = 5; i <= 7; i++) {
addFrame(context.getResources().getDrawable(R.drawable.metronom_light_tock), intervalTick);
addFrame(context.getResources().getDrawable(R.drawable.metronom_light), getIntervalLength(i));
}
setOneShot(false);
}
private int getIntervalLength(int i) {
return numIterationsToOneMs == i ? intervalTock + (-1 * sign) : intervalTock;
}
private void computeValues(double beatsPerMinute) {
double secondsPerBeat = 60.0 / beatsPerMinute * 1000; // in milliseconds
intervalTick = (int) Math.round(secondsPerBeat / 3);
intervalTock = (int) Math.round(secondsPerBeat - (int) Math.round(secondsPerBeat / 3));
double roundError = secondsPerBeat - (intervalTick + intervalTock);
sign = roundError < 0 ? -1 : 1;
numIterationsToOneMs = Math.abs((int) Math.round(1 / roundError));
Log.i("MetronomAnimation", "SPB = " + secondsPerBeat + " intervalTick = " + intervalTick + " intervalTock = "
+ intervalTock);
Log.i("MetronomAnimation", "RoundError = " + roundError + " NumIterMs = " + numIterationsToOneMs);
}
}