mirror of https://github.com/badvision/jace.git
113 lines
3.2 KiB
Java
113 lines
3.2 KiB
Java
/*
|
|
* Copyright (C) 2012 Brendan Robert (BLuRry) brendan.robert@gmail.com.
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* This library 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
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
|
|
* MA 02110-1301 USA
|
|
*/
|
|
package jace.hardware.mockingboard;
|
|
|
|
/**
|
|
* Envelope generator of the PSG sound chip
|
|
* Created on April 18, 2006, 5:49 PM
|
|
* @author Brendan Robert (BLuRry) brendan.robert@gmail.com
|
|
*/
|
|
public class EnvelopeGenerator extends TimedGenerator {
|
|
|
|
boolean hold = false;
|
|
boolean attk = false;
|
|
boolean alt = false;
|
|
boolean cont = false;
|
|
int direction;
|
|
int amplitude;
|
|
|
|
public EnvelopeGenerator(int _clock, int _sampleRate) {
|
|
super(_clock, _sampleRate);
|
|
}
|
|
|
|
@Override
|
|
public int stepsPerCycle() {
|
|
return 8;
|
|
}
|
|
|
|
@Override
|
|
public void setPeriod(int p) {
|
|
if (p > 0) {
|
|
super.setPeriod(p);
|
|
} else {
|
|
clocksPerPeriod = stepsPerCycle() / 2;
|
|
}
|
|
}
|
|
|
|
public void step() {
|
|
int stateChanges = updateCounter();
|
|
for (int i = 0; i < stateChanges; i++) {
|
|
if (amplitude == 0 && direction == -1) {
|
|
if (!cont) {
|
|
direction = 0;
|
|
} else if (hold) {
|
|
direction = 0;
|
|
if (alt) {
|
|
amplitude = 15;
|
|
}
|
|
} else if (alt) {
|
|
direction = 1;
|
|
} else {
|
|
amplitude = 15;
|
|
}
|
|
}
|
|
if (amplitude == 15 && direction == 1) {
|
|
if (!cont) {
|
|
direction = 0;
|
|
amplitude = 0;
|
|
} else if (hold) {
|
|
direction = 0;
|
|
if (alt) {
|
|
amplitude = 0;
|
|
}
|
|
} else if (alt) {
|
|
direction = -1;
|
|
} else {
|
|
amplitude = 0;
|
|
}
|
|
}
|
|
amplitude += direction;
|
|
}
|
|
}
|
|
|
|
public void setShape(int shape) {
|
|
counter = 0;
|
|
cont = (shape & 8) != 0;
|
|
attk = (shape & 4) != 0;
|
|
alt = (shape & 2) != 0;
|
|
hold = (shape & 1) != 0;
|
|
if (attk) {
|
|
amplitude = 0;
|
|
direction = 1;
|
|
} else {
|
|
amplitude = 15;
|
|
direction = -1;
|
|
}
|
|
}
|
|
|
|
public int getAmplitude() {
|
|
return amplitude;
|
|
}
|
|
|
|
@Override
|
|
public void reset() {
|
|
super.reset();
|
|
setShape(0);
|
|
}
|
|
} |