func NewPianoKey(idx int) Key {
const phasefac float64 = 0.5063999999999971
k := &PianoKey{}
k.freq = notes[idx]
k.mod = snd.NewOscil(sqsine, k.freq/2, nil)
k.osc = snd.NewOscil(sawtooth, k.freq, k.mod)
k.phs = snd.NewOscil(square, k.freq*phasefac, nil)
k.osc.SetPhase(k.phs)
freql := k.freq * math.Pow(2, -10.0/1200)
k.modl = snd.NewOscil(sqsine, freql/2, nil)
k.oscl = snd.NewOscil(sawtooth, freql, k.modl)
k.phsl = snd.NewOscil(square, freql*phasefac, nil)
k.oscl.SetPhase(k.phsl)
freqr := k.freq * math.Pow(2, 10.0/1200)
k.modr = snd.NewOscil(sqsine, freqr/2, nil)
k.oscr = snd.NewOscil(sawtooth, freqr, k.modr)
k.phsr = snd.NewOscil(square, freqr*phasefac, nil)
k.oscr.SetPhase(k.phsr)
oscmix := snd.NewMixer(k.osc, k.oscl, k.oscr)
k.reldur = 1050 * ms
k.dur = 280*ms + k.reldur
k.adsr0 = snd.NewADSR(30*ms, 50*ms, 200*ms, k.reldur, 0.4, 1, oscmix)
k.adsr1 = snd.NewADSR(1*ms, 278*ms, 1*ms, k.reldur, 0.4, 1, oscmix)
adsrmix := snd.NewMixer(k.adsr0, k.adsr1)
k.gain = snd.NewGain(snd.Decibel(-10).Amp(), adsrmix)
k.Instrument = snd.NewInstrument(k.gain)
k.Off()
return k
}
func onTouch(ev touch.Event) {
idx := piano.KeyAt(ev, sz)
if idx == -1 {
// top half
switch ev.Type {
case touch.TypeBegin:
if btnreverb.HitTest(ev, sz) {
btnreverb.SetActive(!btnreverb.IsActive())
if btnreverb.IsActive() {
reverb.On()
keygain.SetAmp(snd.Decibel(-3).Amp())
} else {
reverb.Off()
keygain.SetAmp(snd.Decibel(3).Amp())
}
} else if btnlowpass.HitTest(ev, sz) {
btnlowpass.SetActive(!btnlowpass.IsActive())
lowpass.SetPassthrough(!btnlowpass.IsActive())
} else if btnmetronome.HitTest(ev, sz) {
btnmetronome.SetActive(!btnmetronome.IsActive())
if btnmetronome.IsActive() {
metronome.On()
} else {
metronome.Off()
}
} else if btnloop.HitTest(ev, sz) {
if !btnloop.IsActive() {
btnloop.SetActiveColor(1, 1, 0, 0.5)
btnloop.SetActive(true)
loop.Record()
} else {
loop.Stop()
}
} else if btnsndbank.HitTest(ev, sz) {
sndbankpos = (sndbankpos + 1) % len(sndbank)
btnsndbank.SetActiveColor(sndbankcolor())
go makekeys()
}
case touch.TypeMove:
}
// TODO drag finger off piano and it still plays, shouldn't return here
// to allow TypeMove to figure out what to turn off
return
}
if keys[idx] == nil {
return
}
switch ev.Type {
case touch.TypeBegin:
keys[idx].Press()
touchseq[ev.Sequence] = idx
case touch.TypeMove:
// TODO drag finger off piano and it still plays, should stop
if lastidx, ok := touchseq[ev.Sequence]; ok {
if idx != lastidx {
keys[lastidx].Release()
keys[idx].Press()
touchseq[ev.Sequence] = idx
}
}
case touch.TypeEnd:
keys[idx].Release()
delete(touchseq, ev.Sequence)
default:
}
}
func onStart(ctx gl.Context) {
ctx.Enable(gl.BLEND)
ctx.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
if err := al.OpenDevice(buffers); err != nil {
log.Fatal(err)
}
var err error
keymix = snd.NewMixer()
go makekeys()
lowpass = snd.NewLowPass(773, keymix)
keygain = snd.NewGain(snd.Decibel(-3).Amp(), lowpass)
dly := snd.NewDelay(29*time.Millisecond, keygain)
tap0 := snd.NewTap(19*time.Millisecond, dly)
tap1 := snd.NewTap(13*time.Millisecond, dly)
tap2 := snd.NewTap(7*time.Millisecond, dly)
cmb := snd.NewComb(snd.Decibel(-3).Amp(), 11*time.Millisecond, snd.NewMixer(dly, tap0, tap1, tap2))
reverb = snd.NewLowPass(2000, cmb)
dlymix := snd.NewMixer(reverb, keygain)
loop = snd.NewLoopFrames(loopdur, dlymix)
loop.SetBPM(bpm)
loopmix := snd.NewMixer(dlymix, loop)
master = snd.NewMixer(loopmix)
mastergain = snd.NewGain(snd.Decibel(-6).Amp(), master)
mixwf, err = snd.NewWaveform(ctx, 2, mastergain)
if err != nil {
log.Fatal(err)
}
pan := snd.NewPan(0, mixwf)
mtrosc := snd.NewOscil(sine, 440, nil)
mtrdmp := snd.NewDamp(bpm.Dur(), mtrosc)
metronome = snd.NewMixer(mtrdmp)
metronome.Off()
master.Append(metronome)
piano = NewPiano()
pianowf, err = snd.NewWaveform(ctx, 1, piano)
if err != nil {
log.Fatal(err)
}
al.AddSource(pan)
yoff := float32(-0) //.12)
btnreverb = snd.NewButton(ctx, -0.98, 0.96+yoff, 0.2, -0.2)
btnreverb.SetActiveColor(0, 1, 0, 0.5)
btnreverb.SetActive(true)
btnlowpass = snd.NewButton(ctx, -0.76, 0.96+yoff, 0.2, -0.2)
btnlowpass.SetActiveColor(0, 1, 1, 0.5)
btnlowpass.SetActive(true)
btnmetronome = snd.NewButton(ctx, -0.54, 0.96+yoff, 0.2, -0.2)
btnmetronome.SetActiveColor(0, 0, 1, 0.5)
btnloop = snd.NewLoopButton(snd.NewButton(ctx, -0.32, 0.96+yoff, 0.2, -0.2), loop)
btnloop.SetActiveColor(1, 0, 0, 0.5)
btnsndbank = snd.NewButton(ctx, 0.78, 0.96+yoff, 0.2, -0.2)
btnsndbank.SetActive(true)
btnsndbank.SetActiveColor(sndbankcolor())
}