// drawSignal writes the input wave form(s) out to screen.
func (s *SpectrogramScreen) drawSignal() {
s.eventBuffer.Each(func(index int, value interface{}) {
if value != nil {
e := value.(Event)
gl.Color3f(e.R, e.G, e.B)
x := float64(index) * s.pixelsPerSample
gl.Begin(gl.LINE_STRIP)
gl.Vertex2d(x, -1.0)
gl.Vertex2d(x, 1.0)
gl.End()
}
})
spacing := 1
gl.PointSize(1.0)
gl.Begin(gl.POINTS)
s.line.valueBuffer.Each(func(index int, value interface{}) {
col := value.([]complex128)
for i, v := range col {
// p = log(|v|) = [-20, 5], so map to [0, 1]
// p := math.Log(cmplx.Abs(v) + 1.e-8)
// grey := (p + 20.0) / 25.0
p := cmplx.Abs(v)
grey := p / 15.0
if grey > 1.0 {
grey = 1.0
} else if grey < 0.0 {
grey = 0.0
}
// HACK: Stretch to make the darks darker and the whites whiter.
// grey = grey * grey * grey * grey // more space at the top, [0, 1]
// grey = 2.0 * grey - 1.0 // [-1, 1]
// grey = math.Tanh(2.0 * grey) // streched, still [-1, 1]
// grey = (grey + 1.0) / 2.0
gl.Color3d(grey, grey, grey)
// gl.Vertex2d(float64(index)*s.pixelsPerSample, float64(s.height - 1 - (3 * i + 0)))
gl.Vertex2d(float64(index)*s.pixelsPerSample, float64(s.height-1-(spacing*i)))
// gl.Vertex2d(float64(index)*s.pixelsPerSample, float64(s.height - 1 - (3 * i + 2)))
}
gl.Color3ub(255, 0, 0)
for i := 1; i < 7; i++ {
gl.Vertex2d(float64(index)*s.pixelsPerSample, float64(i*spacing*s.bpo))
}
})
gl.End()
}
// drawSignal writes the input wave form(s) out to screen.
func (s *Screen) drawSignal() {
s.eventBuffer.Each(func(index int, value interface{}) {
if value != nil {
e := value.(Event)
gl.Color3f(e.R, e.G, e.B)
x := float64(index) * s.pixelsPerSample
gl.Begin(gl.LINE_STRIP)
gl.Vertex2d(x, -1.0)
gl.Vertex2d(x, 1.0)
gl.End()
}
})
for _, l := range s.lines {
gl.Color3f(l.R, l.G, l.B)
gl.Begin(gl.LINE_STRIP)
l.valueBuffer.Each(func(index int, value float64) {
gl.Vertex2d(float64(index)*s.pixelsPerSample, value)
})
gl.End()
}
}