private float _vibratoPhase; // Phase through the vibrato sine wave
#endregion Fields
#region Constructors
public Synth(SynthParams sfxParams)
{
GenerateAudioData(sfxParams);
}
private float[] GenerateAudioData(SynthParams sfxParams)
{
float[] buffer = null;
bool _finished = false;
for (int i = 0; i < buffer.Length; i++)
{
if (_finished) return buffer;
// Repeats every _repeatLimit times, partially resetting the sound parameters
if (sfxParams.RepeatLimit > 0)
{
if (++_repeatTime >= sfxParams.RepeatLimit)
{
_repeatTime = 0;
Reset(false);
}
}
// If _changeLimit is reached, shifts the pitch
if (_changeLimit != 0)
{
if (++_changeTime >= _changeLimit)
{
_changeLimit = 0;
_period *= sfxParams.ChangeAmount;
}
}
// Acccelerate and apply slide
sfxParams.Slide += sfxParams.DeltaSlide;
_period *= sfxParams.Slide;
// Checks for frequency getting too low, and stops the sound if a minFrequency was set
if (_period > _maxPeriod)
{
_period = _maxPeriod;
if (sfxParams.MinFrequency > 0) _finished = true;
}
_periodTemp = _period;
if (sfxParams.IsVibratoEnabled)
{
_vibratoPhase += sfxParams.VibratoSpeed;
_periodTemp = _period * (float)(1.0f + Math.Sin(_vibratoPhase) * sfxParams.VibratoDepth);
}
_periodTemp = Math.Max((int)_periodTemp,8);
if (sfxParams.WaveShape == SynthParams.WaveShapeEnum.Square)
{
sfxParams.SquareDuty += sfxParams.DutySweep;
if (sfxParams.SquareDuty < 0.0) sfxParams.SquareDuty = 0.0f;
if (sfxParams.SquareDuty > 0.5) sfxParams.SquareDuty = 0.5f;
}
// Moves through the different stages of the volume envelope
if (++_envelopeTime > _envelopeLength) {
_envelopeTime = 0;
switch (++_envelopeStage) {
case 1:
_envelopeLength = _envelopeLength1;
break;
case 2:
_envelopeLength = _envelopeLength2;
break;
}
}
// Sets the volume based on the position in the envelope
switch (_envelopeStage) {
case 0:
_envelopeVolume = _envelopeTime * _envelopeOverLength0;
break;
case 1:
_envelopeVolume = 1.0f + (1.0f - _envelopeTime * _envelopeOverLength1) * 2.0f * sfxParams.SustainPunch;
break;
case 2:
_envelopeVolume = 1.0f - _envelopeTime * _envelopeOverLength2;
break;
case 3:
_envelopeVolume = 0.0f;
_finished = true;
break;
}
if (sfxParams.IsPhaserEnabled)
{
_phaserOffset += _phaserDeltaOffset;
_phaserInt = (int)_phaserOffset;
if (_phaserInt < 0) _phaserInt = -_phaserInt;
if (_phaserInt > 1023) _phaserInt = 1023;
}
if (sfxParams.IsFilterEnabled && Math.Abs(sfxParams.HighPassFilterCutoffSweep) > TOLERANCE) {
sfxParams.HighPassFilterCutoff *= sfxParams.HighPassFilterCutoffSweep;
if (sfxParams.HighPassFilterCutoff < 0.00001f)
sfxParams.HighPassFilterCutoff = 0.00001f;
if (sfxParams.HighPassFilterCutoff > 0.1f)
sfxParams.HighPassFilterCutoff = 0.1f;
}
_superSample = 0;
// Generates 8 samples which are averaged out to produce superSample
for (int cycle = 0; cycle < 8; cycle++)
{
if (++_phase >= _periodTemp) _phase = _phase % (int)_periodTemp;
switch (sfxParams.WaveShape)
{
case SynthParams.WaveShapeEnum.Square:
_sample = ((_phase / _periodTemp) < sfxParams.SquareDuty) ? 0.5f : -0.5f;
break;
case SynthParams.WaveShapeEnum.Saw:
_sample = 1.0f - (_phase / _periodTemp) * 2.0f;
break;
case SynthParams.WaveShapeEnum.Sine:
_pos = _phase / _periodTemp;
_pos = _pos > 0.5f ? (_pos - 1.0f) * 6.28318531f : _pos * 6.28318531f;
_sample = _pos < 0 ? 1.27323954f * _pos + 0.405284735f * _pos * _pos : 1.27323954f * _pos - 0.405284735f * _pos * _pos;
_sample = _sample < 0 ? 0.225f * (_sample * -_sample - _sample) + _sample : 0.225f * (_sample * _sample - _sample) + _sample;
break;
case SynthParams.WaveShapeEnum.Noise:
_sample = GetRandom.Float(-1, 1);
break;
}
// Applies the low and high pass filters
if (sfxParams.IsFilterEnabled) {
_lpFilterOldPos = _lpFilterPos;
sfxParams.LowPassFilterCutoff *= sfxParams.LowPassFilterCutoffSweep;
if (sfxParams.LowPassFilterCutoff < 0.0) sfxParams.LowPassFilterCutoff = 0.0f;
if (sfxParams.LowPassFilterCutoff > 0.1) sfxParams.LowPassFilterCutoff = 0.1f;
if (sfxParams.IsLowPassFilterEnabled) {
_lpFilterDeltaPos += (_sample - _lpFilterPos) * sfxParams.LowPassFilterCutoff;
_lpFilterDeltaPos *= _lpFilterDamping;
} else {
_lpFilterPos = _sample;
_lpFilterDeltaPos = 0.0f;
}
_lpFilterPos += _lpFilterDeltaPos;
_hpFilterPos += _lpFilterPos - _lpFilterOldPos;
_hpFilterPos *= 1.0f - sfxParams.HighPassFilterCutoff;
_sample = _hpFilterPos;
}
if (sfxParams.IsPhaserEnabled) {
_phaserBuffer[_phaserPos & 1023] = _sample;
_sample += _phaserBuffer[(_phaserPos - _phaserInt + 1024) & 1023];
_phaserPos = (_phaserPos + 1) & 1023;
}
_superSample += _sample;
}
// Averages out the super samples and applies volumes
_superSample = sfxParams.MasterVolume * _envelopeVolume * _superSample * 0.125f;
// Apply clipping
if (_superSample < -1f) _superSample = -1f;
if (_superSample > 1f) _superSample = 1f;
// Writes value to list, ignoring left/right sound channels (this is applied when filtering the audio later)
buffer[i] = _superSample;
}
return buffer;
}
public static SynthParams Powerup()
{
var result = new SynthParams();
if (GetRandom.Bool())
{
result.WaveShape = WaveShapeEnum.Saw;
}
else
{
result.SquareDuty = GetRandom.Float(0.6f);
}
if (GetRandom.Bool())
{
result.StartFrequency = GetRandom.Float(0.2f, 0.5f);
result.Slide = GetRandom.Float(0.1f, 0.5f);
result.RepeatSpeed = GetRandom.Float(0.4f, 0.8f);
}
else
{
result.StartFrequency = GetRandom.Float(0.2f, 0.5f);
result.Slide = GetRandom.Float(0.05f, 0.25f);
if (GetRandom.Bool())
{
result.VibratoDepth = GetRandom.Float(0.7f);
result.VibratoSpeed = GetRandom.Float(0.6f);
}
}
result.SustainTime = GetRandom.Float(0.4f);
result.DecayTime = GetRandom.Float(0.1f, 0.5f);
return result;
}
public static SynthParams Random()
{
var result = new SynthParams
{
WaveShape = (WaveShapeEnum) (GetRandom.Float()*4f),
AttackTime = (float) Math.Pow(GetRandom.Float(-1, 1), 4),
SustainTime = (float) Math.Pow(GetRandom.Float(-1, 1), 2),
SustainPunch = (float) Math.Pow(GetRandom.Float(0.8f), 2),
DecayTime = GetRandom.Float(),
StartFrequency = (GetRandom.Bool()) ? (float) Math.Pow(GetRandom.Float(-1, 1), 2) : ((float) Math.Pow(GetRandom.Float(0.5f), 3) + 0.5f),
MinFrequency = 0.0f,
Slide = (float) Math.Pow(GetRandom.Float(-1, 1), 5),
DeltaSlide = (float) Math.Pow(GetRandom.Float(-1, 1), 3),
VibratoDepth = (float) Math.Pow(GetRandom.Float(-1, 1), 3),
VibratoSpeed = GetRandom.Float(-1, 1),
ChangeAmount = GetRandom.Float(-1, 1),
ChangeSpeed = GetRandom.Float(-1, 1),
SquareDuty = GetRandom.Float(-1, 1),
DutySweep = (float) Math.Pow(GetRandom.Float(-1, 1), 3),
RepeatSpeed = GetRandom.Float(-1, 1),
PhaserOffset = (float) Math.Pow(GetRandom.Float(-1, 1), 3),
PhaserSweep = (float) Math.Pow(GetRandom.Float(-1, 1), 3),
LowPassFilterCutoff = 1f - (float) Math.Pow(GetRandom.Float(), 3),
LowPassFilterCutoffSweep = (float) Math.Pow(GetRandom.Float(-1, 1), 3),
LowPassFilterResonance = GetRandom.Float(-1, 1),
HighPassFilterCutoff = (float) Math.Pow(GetRandom.Float(), 5),
HighPassFilterCutoffSweep = (float) Math.Pow(GetRandom.Float(-1, 1), 5),
};
if (result.AttackTime + result.SustainTime + result.DecayTime < 0.2f)
{
result.SustainTime = GetRandom.Float(0.2f, 0.5f);
result.DecayTime = GetRandom.Float(0.2f, 0.5f);
}
if ((result.StartFrequency > 0.7f && result.Slide > 0.2) || (result.StartFrequency < 0.2 && result.Slide < -0.05))
{
result.Slide = -result.Slide;
}
if (result.LowPassFilterCutoff < 0.1f && result.LowPassFilterCutoffSweep < -0.05f)
{
result.LowPassFilterCutoffSweep = -result.LowPassFilterCutoffSweep;
}
return result;
}
public static SynthParams MenuBlip()
{
var result = new SynthParams();
result.WaveShape = (WaveShapeEnum) (GetRandom.Int(2));
if (result.WaveShape == WaveShapeEnum.Square) result.SquareDuty = GetRandom.Float(0.6f);
result.StartFrequency = GetRandom.Float(0.2f, 0.6f);
result.SustainTime = GetRandom.Float(0.1f, 0.2f);
result.DecayTime = GetRandom.Float(0.2f);
result.HighPassFilterCutoff = 0.1f;
return result;
}
public static SynthParams PlayerHurt()
{
var result = new SynthParams();
result.WaveShape = (WaveShapeEnum)(GetRandom.Int(3));
if (result.WaveShape == WaveShapeEnum.Sine) result.WaveShape = WaveShapeEnum.Noise;
if (result.WaveShape == WaveShapeEnum.Square) result.SquareDuty = GetRandom.Float(0.6f);
result.StartFrequency = GetRandom.Float(0.2f, 0.8f);
result.Slide = GetRandom.Float(-0.3f, 0.1f);
result.SustainTime = GetRandom.Float(0.1f);
result.DecayTime = GetRandom.Float(0.1f,0.3f);
if (GetRandom.Bool()) result.HighPassFilterCutoff = GetRandom.Float(0.3f);
return result;
}
public static SynthParams Laser()
{
var result = new SynthParams();
result.WaveShape = (WaveShapeEnum)(GetRandom.Int(3));
result.StartFrequency = GetRandom.Float(0.5f,1);
result.MinFrequency = result.StartFrequency - 0.2f - GetRandom.Float() * 0.6f;
if (result.MinFrequency < 0.2f) result.MinFrequency = 0.2f;
result.Slide = -0.15f - GetRandom.Float() * 0.2f;
if (GetRandom.Float() < 0.33f) {
result.StartFrequency = 0.3f + GetRandom.Float() * 0.6f;
result.MinFrequency = GetRandom.Float(0.1f);
result.Slide = GetRandom.Float(-0.65f,-0.35f);
}
if (GetRandom.Bool()) {
result.SquareDuty = GetRandom.Float(0.5f);
result.DutySweep = GetRandom.Float(0.2f);
} else {
result.SquareDuty = GetRandom.Float(0.4f,0.9f);
result.DutySweep = -GetRandom.Float(0.7f);
}
result.SustainTime = GetRandom.Float(0.1f,0.3f);
result.DecayTime = GetRandom.Float(0.4f);
if (GetRandom.Bool()) result.SustainPunch = GetRandom.Float(0.3f);
if (GetRandom.Bool(1/3)) {
result.PhaserOffset = GetRandom.Float(0.2f);
result.PhaserSweep = GetRandom.Float(-0.2f,0);
}
if (GetRandom.Bool()) result.HighPassFilterCutoff = GetRandom.Float(0.3f);
return result;
}
public static SynthParams Jump()
{
var result = new SynthParams();
result.WaveShape = WaveShapeEnum.Square;
result.SquareDuty = GetRandom.Float(0.6f);
result.StartFrequency = GetRandom.Float(0.3f, 0.6f);
result.Slide = GetRandom.Float(0.1f, 0.3f);
result.SustainTime = GetRandom.Float(0.1f, 0.4f);
result.DecayTime = GetRandom.Float(0.1f, 0.3f);
if (GetRandom.Bool()) result.HighPassFilterCutoff = GetRandom.Float(0.3f);
if (GetRandom.Bool()) result.LowPassFilterCutoff = GetRandom.Float(0.4f, 1.0f);
return result;
}
public static SynthParams Explosion()
{
var result = new SynthParams();
result.WaveShape = WaveShapeEnum.Noise;
if (GetRandom.Bool()) {
result.StartFrequency = GetRandom.Float(0.1f,0.5f);
result.Slide = -0.1f + GetRandom.Float() * 0.4f;
} else {
result.StartFrequency = GetRandom.Float(0.2f,0.9f);
result.Slide = GetRandom.Float(-0.2f,0);
}
result.StartFrequency *= result.StartFrequency;
if (GetRandom.Bool(1/5)) result.Slide = 0;
if (GetRandom.Bool(1/3)) result.RepeatSpeed = GetRandom.Float(0.3f,0.8f);
result.SustainTime = GetRandom.Float(0.1f,0.4f);
result.DecayTime = GetRandom.Float(0.5f);
result.SustainPunch = GetRandom.Float(0.2f,0.8f);
if (GetRandom.Bool()) {
result.PhaserOffset = GetRandom.Float(-0.3f, 0.6f);
result.PhaserSweep = GetRandom.Float(-0.3f,0);
}
if (GetRandom.Bool(1/3)) {
result.ChangeSpeed = GetRandom.Float(0.6f,0.9f);
result.ChangeAmount = GetRandom.Float(0.8f,0.8f);
}
return result;
}
public static SynthParams Default()
{
var result = new SynthParams();
result.Reset();
return result;
}
public static SynthParams Coin()
{
var result = new SynthParams();
result.StartFrequency = GetRandom.Float(0.4f, 0.9f);
result.SustainTime = GetRandom.Float(0.1f);
result.DecayTime = GetRandom.Float(0.1f, 0.5f);
result.SustainPunch = GetRandom.Float(0.3f, 0.6f);
if (GetRandom.Bool())
{
result.ChangeSpeed = GetRandom.Float(0.5f, 0.7f);
result.ChangeAmount = GetRandom.Float(0.2f, 0.6f);
}
return result;
}