public void Start(RegionPair region, int channel, int key, int velocity)
{
this.exclusiveClass = region.ExclusiveClass;
this.channel = channel;
this.key = key;
this.velocity = velocity;
if (velocity > 0)
{
// According to the Polyphone's implementation, the initial attenuation should be reduced to 40%.
// I'm not sure why, but this indeed improves the loudness variability.
var sampleAttenuation = 0.4F * region.InitialAttenuation;
var filterAttenuation = 0.5F * region.InitialFilterQ;
var decibels = 2 * SoundFontMath.LinearToDecibels(velocity / 127F) - sampleAttenuation - filterAttenuation;
noteGain = SoundFontMath.DecibelsToLinear(decibels);
}
else
{
noteGain = 0F;
}
cutoff = region.InitialFilterCutoffFrequency;
resonance = SoundFontMath.DecibelsToLinear(region.InitialFilterQ);
vibLfoToPitch = 0.01F * region.VibratoLfoToPitch;
modLfoToPitch = 0.01F * region.ModulationLfoToPitch;
modEnvToPitch = 0.01F * region.ModulationEnvelopeToPitch;
modLfoToCutoff = region.ModulationLfoToFilterCutoffFrequency;
modEnvToCutoff = region.ModulationEnvelopeToFilterCutoffFrequency;
dynamicCutoff = modLfoToCutoff != 0 || modEnvToCutoff != 0;
modLfoToVolume = region.ModulationLfoToVolume;
dynamicVolume = modLfoToVolume > 0.05F;
instrumentPan = SoundFontMath.Clamp(region.Pan, -50F, 50F);
instrumentReverb = 0.01F * region.ReverbEffectsSend;
instrumentChorus = 0.01F * region.ChorusEffectsSend;
volEnv.Start(region, key, velocity);
modEnv.Start(region, key, velocity);
vibLfo.StartVibrato(region, key, velocity);
modLfo.StartModulation(region, key, velocity);
oscillator.Start(synthesizer.SoundFont.WaveDataArray, region);
filter.ClearBuffer();
filter.SetLowPassFilter(cutoff, resonance);
smoothedCutoff = cutoff;
voiceState = VoiceState.Playing;
voiceLength = 0;
}
public static void Start(this ModulationEnvelope envelope, RegionPair region, int key, int velocity)
{
// According to the implementation of TinySoundFont, the attack time should be adjusted by the velocity.
var delay = region.DelayModulationEnvelope;
var attack = region.AttackModulationEnvelope * ((145 - velocity) / 144F);
var hold = region.HoldModulationEnvelope * SoundFontMath.KeyNumberToMultiplyingFactor(region.KeyNumberToModulationEnvelopeHold, key);
var decay = region.DecayModulationEnvelope * SoundFontMath.KeyNumberToMultiplyingFactor(region.KeyNumberToModulationEnvelopeDecay, key);
var sustain = 1F - region.SustainModulationEnvelope / 100F;
var release = region.ReleaseModulationEnvelope;
envelope.Start(delay, attack, hold, decay, sustain, release);
}
public static void Start(this VolumeEnvelope envelope, RegionPair region, int key, int velocity)
{
// If the release time is shorter than 10 ms, it will be clamped to 10 ms to avoid pop noise.
var delay = region.DelayVolumeEnvelope;
var attack = region.AttackVolumeEnvelope;
var hold = region.HoldVolumeEnvelope * SoundFontMath.KeyNumberToMultiplyingFactor(region.KeyNumberToVolumeEnvelopeHold, key);
var decay = region.DecayVolumeEnvelope * SoundFontMath.KeyNumberToMultiplyingFactor(region.KeyNumberToVolumeEnvelopeDecay, key);
var sustain = SoundFontMath.DecibelsToLinear(-region.SustainVolumeEnvelope);
var release = Math.Max(region.ReleaseVolumeEnvelope, 0.01F);
envelope.Start(delay, attack, hold, decay, sustain, release);
}
/// <summary>
/// Starts a note.
/// </summary>
/// <param name="channel">The channel of the note.</param>
/// <param name="key">The key of the note.</param>
/// <param name="velocity">The velocity of the note.</param>
public void NoteOn(int channel, int key, int velocity)
{
if (velocity == 0)
{
NoteOff(channel, key);
return;
}
if (!(0 <= channel && channel < channels.Length))
{
return;
}
var channelInfo = channels[channel];
var presetId = (channelInfo.BankNumber << 16) | channelInfo.PatchNumber;
Preset preset;
if (!presetLookup.TryGetValue(presetId, out preset))
{
// Try fallback to the GM sound set.
if (!presetLookup.TryGetValue(channelInfo.PatchNumber, out preset))
{
// No corresponding preset was found. Use the default one...
preset = defaultPreset;
}
}
foreach (var presetRegion in preset.RegionArray)
{
if (presetRegion.Contains(key, velocity))
{
foreach (var instrumentRegion in presetRegion.Instrument.RegionArray)
{
if (instrumentRegion.Contains(key, velocity))
{
var regionPair = new RegionPair(presetRegion, instrumentRegion);
var voice = voices.RequestNew(instrumentRegion, channel);
if (voice != null)
{
voice.Start(regionPair, channel, key, velocity);
}
}
}
}
}
}
public static void Start(this Oscillator oscillator, short[] data, RegionPair region)
{
var sampleRate = region.Instrument.Sample.SampleRate;
var loopMode = region.SampleModes;
var start = region.SampleStart;
var end = region.SampleEnd;
var startLoop = region.SampleStartLoop;
var endLoop = region.SampleEndLoop;
var rootKey = region.RootKey;
var coarseTune = region.CoarseTune;
var fineTune = region.FineTune;
var scaleTuning = region.ScaleTuning;
oscillator.Start(data, loopMode, sampleRate, start, end, startLoop, endLoop, rootKey, coarseTune, fineTune, scaleTuning);
}
public static void StartModulation(this Lfo lfo, RegionPair region, int key, int velocity)
{
lfo.Start(region.DelayModulationLfo, region.FrequencyModulationLfo);
}
public static void StartVibrato(this Lfo lfo, RegionPair region, int key, int velocity)
{
lfo.Start(region.DelayVibratoLfo, region.FrequencyVibratoLfo);
}
