Files
sointu/tracker/gioui/oscilloscope.go
2025-06-23 09:43:10 +03:00

204 lines
7.2 KiB
Go

package gioui
import (
"image"
"image/color"
"math"
"gioui.org/f32"
"gioui.org/io/event"
"gioui.org/io/pointer"
"gioui.org/layout"
"gioui.org/op/clip"
"gioui.org/op/paint"
"gioui.org/unit"
"github.com/vsariola/sointu/tracker"
)
type (
OscilloscopeState struct {
onceBtn *Clickable
wrapBtn *Clickable
lengthInBeatsNumber *NumericUpDownState
triggerChannelNumber *NumericUpDownState
xScale int
xOffset float32
yScale float64
dragging bool
dragId pointer.ID
dragStartPoint f32.Point
}
OscilloscopeStyle struct {
CurveColors [2]color.NRGBA `yaml:",flow"`
LimitColor color.NRGBA `yaml:",flow"`
CursorColor color.NRGBA `yaml:",flow"`
}
)
func NewOscilloscope(model *tracker.Model) *OscilloscopeState {
return &OscilloscopeState{
onceBtn: new(Clickable),
wrapBtn: new(Clickable),
lengthInBeatsNumber: NewNumericUpDownState(),
triggerChannelNumber: NewNumericUpDownState(),
}
}
func (s *OscilloscopeState) Layout(gtx C, vtrig, vlen tracker.Int, once, wrap tracker.Bool, wave tracker.RingBuffer[[2]float32], th *Theme, st *OscilloscopeStyle) D {
leftSpacer := layout.Spacer{Width: unit.Dp(6), Height: unit.Dp(24)}.Layout
rightSpacer := layout.Spacer{Width: unit.Dp(6)}.Layout
triggerChannel := NumUpDown(vtrig, th, s.triggerChannelNumber, "Trigger channel")
lengthInBeats := NumUpDown(vlen, th, s.lengthInBeatsNumber, "Buffer length in beats")
onceBtn := ToggleBtn(once, th, s.onceBtn, "Once", "Trigger once on next event")
wrapBtn := ToggleBtn(wrap, th, s.wrapBtn, "Wrap", "Wrap buffer when full")
return layout.Flex{Axis: layout.Vertical}.Layout(gtx,
layout.Flexed(1, func(gtx C) D { return s.layoutWave(gtx, wave, th) }),
layout.Rigid(func(gtx C) D {
return layout.Flex{Axis: layout.Horizontal, Alignment: layout.Middle}.Layout(gtx,
layout.Rigid(leftSpacer),
layout.Rigid(Label(th, &th.SongPanel.RowHeader, "Trigger").Layout),
layout.Flexed(1, func(gtx C) D { return D{Size: gtx.Constraints.Min} }),
layout.Rigid(onceBtn.Layout),
layout.Rigid(triggerChannel.Layout),
layout.Rigid(rightSpacer),
)
}),
layout.Rigid(func(gtx C) D {
return layout.Flex{Axis: layout.Horizontal, Alignment: layout.Middle}.Layout(gtx,
layout.Rigid(leftSpacer),
layout.Rigid(Label(th, &th.SongPanel.RowHeader, "Buffer").Layout),
layout.Flexed(1, func(gtx C) D { return D{Size: gtx.Constraints.Min} }),
layout.Rigid(wrapBtn.Layout),
layout.Rigid(lengthInBeats.Layout),
layout.Rigid(rightSpacer),
)
}),
)
}
func (s *OscilloscopeState) layoutWave(gtx C, wave tracker.RingBuffer[[2]float32], th *Theme) D {
s.update(gtx, wave)
if gtx.Constraints.Max.X == 0 || gtx.Constraints.Max.Y == 0 {
return D{}
}
defer clip.Rect(image.Rectangle{Max: gtx.Constraints.Max}).Push(gtx.Ops).Pop()
event.Op(gtx.Ops, s)
paint.ColorOp{Color: th.Oscilloscope.CursorColor}.Add(gtx.Ops)
cursorX := int(s.sampleToPx(gtx, float32(wave.Cursor), wave))
fillRect(gtx, clip.Rect{Min: image.Pt(cursorX, 0), Max: image.Pt(cursorX+1, gtx.Constraints.Max.Y)})
paint.ColorOp{Color: th.Oscilloscope.LimitColor}.Add(gtx.Ops)
minusOneY := int(s.ampToY(gtx, -1))
fillRect(gtx, clip.Rect{Min: image.Pt(0, minusOneY), Max: image.Pt(gtx.Constraints.Max.X, minusOneY+1)})
plusOneY := int(s.ampToY(gtx, 1))
fillRect(gtx, clip.Rect{Min: image.Pt(0, plusOneY), Max: image.Pt(gtx.Constraints.Max.X, plusOneY+1)})
leftX := int(s.sampleToPx(gtx, 0, wave))
fillRect(gtx, clip.Rect{Min: image.Pt(leftX, 0), Max: image.Pt(leftX+1, gtx.Constraints.Max.Y)})
rightX := int(s.sampleToPx(gtx, float32(len(wave.Buffer)-1), wave))
fillRect(gtx, clip.Rect{Min: image.Pt(rightX, 0), Max: image.Pt(rightX+1, gtx.Constraints.Max.Y)})
for chn := range 2 {
paint.ColorOp{Color: th.Oscilloscope.CurveColors[chn]}.Add(gtx.Ops)
for px := range gtx.Constraints.Max.X {
// left and right is the sample range covered by the pixel
left := int(s.pxToSample(gtx, float32(px)-0.5, wave))
right := int(s.pxToSample(gtx, float32(px)+0.5, wave))
if right < 0 || left >= len(wave.Buffer) {
continue
}
right = min(right, len(wave.Buffer)-1)
left = max(left, 0)
// smin and smax are the smallest and largest sample values in the pixel range
smax := float32(math.Inf(-1))
smin := float32(math.Inf(1))
for x := left; x <= right; x++ {
smax = max(smax, wave.Buffer[x][chn])
smin = min(smin, wave.Buffer[x][chn])
}
// y1 and y2 are the pixel range covered by the sample value
y1 := min(max(int(s.ampToY(gtx, smax)+0.5), 0), gtx.Constraints.Max.Y-1)
y2 := min(max(int(s.ampToY(gtx, smin)+0.5), 0), gtx.Constraints.Max.Y-1)
fillRect(gtx, clip.Rect{Min: image.Pt(px, y1), Max: image.Pt(px+1, y2+1)})
}
}
return D{Size: image.Pt(gtx.Constraints.Max.X, gtx.Constraints.Max.Y)}
}
func fillRect(gtx C, rect clip.Rect) {
stack := rect.Push(gtx.Ops)
paint.PaintOp{}.Add(gtx.Ops)
stack.Pop()
}
func (o *OscilloscopeState) update(gtx C, wave tracker.RingBuffer[[2]float32]) {
for {
ev, ok := gtx.Event(pointer.Filter{
Target: o,
Kinds: pointer.Scroll | pointer.Press | pointer.Drag | pointer.Release | pointer.Cancel,
ScrollY: pointer.ScrollRange{Min: -1e6, Max: 1e6},
})
if !ok {
break
}
if e, ok := ev.(pointer.Event); ok {
switch e.Kind {
case pointer.Scroll:
s1 := o.pxToSample(gtx, e.Position.X, wave)
o.xScale += min(max(-1, int(e.Scroll.Y)), 1)
s2 := o.pxToSample(gtx, e.Position.X, wave)
o.xOffset -= s1 - s2
case pointer.Press:
if e.Buttons&pointer.ButtonSecondary != 0 {
o.xOffset = 0
o.xScale = 0
o.yScale = 0
}
if e.Buttons&pointer.ButtonPrimary != 0 {
o.dragging = true
o.dragId = e.PointerID
o.dragStartPoint = e.Position
}
case pointer.Drag:
if e.Buttons&pointer.ButtonPrimary != 0 && o.dragging && e.PointerID == o.dragId {
deltaX := o.pxToSample(gtx, e.Position.X, wave) - o.pxToSample(gtx, o.dragStartPoint.X, wave)
o.xOffset += deltaX
num := o.yToAmp(gtx, e.Position.Y)
den := o.yToAmp(gtx, o.dragStartPoint.Y)
if l := math.Abs(float64(num / den)); l > 1e-3 && l < 1e3 {
o.yScale += math.Log(l)
o.yScale = min(max(o.yScale, -1e3), 1e3)
}
o.dragStartPoint = e.Position
}
case pointer.Release | pointer.Cancel:
o.dragging = false
}
}
}
}
func (o *OscilloscopeState) scaleFactor() float32 {
return float32(math.Pow(1.1, float64(o.xScale)))
}
func (s *OscilloscopeState) pxToSample(gtx C, px float32, wave tracker.RingBuffer[[2]float32]) float32 {
return px*s.scaleFactor()*float32(len(wave.Buffer))/float32(gtx.Constraints.Max.X) - s.xOffset
}
func (s *OscilloscopeState) sampleToPx(gtx C, sample float32, wave tracker.RingBuffer[[2]float32]) float32 {
return (sample + s.xOffset) * float32(gtx.Constraints.Max.X) / float32(len(wave.Buffer)) / s.scaleFactor()
}
func (s *OscilloscopeState) ampToY(gtx C, amp float32) float32 {
scale := float32(math.Exp(s.yScale))
return (1 - amp*scale) / 2 * float32(gtx.Constraints.Max.Y-1)
}
func (s *OscilloscopeState) yToAmp(gtx C, y float32) float32 {
scale := float32(math.Exp(s.yScale))
return (1 - y/float32(gtx.Constraints.Max.Y-1)*2) / scale
}