func (self *LineChart) drawSeries(x, y, w, h float64, ctx vg.Context) {
// Boundries
baseline := y + h
_, max, count := self.Model.Limits()
horIncr := w / (count - 1)
vratio := (h - 1) / max
for _, s := range self.Model.Series() {
c1 := CloneColor(s.Color)
c1.A = 150
ctx.StrokeColor(c1)
ctx.StrokeWidth(s.StrokeWidth)
ctx.BeginPath()
for i, f := range s.Data {
if i == 0 {
ctx.MoveTo(x+float64(i)*horIncr, baseline-(f*vratio))
} else {
ctx.LineTo(x+float64(i)*horIncr, baseline-(f*vratio))
}
}
ctx.Stroke()
if self.Fill {
ctx.BeginPath()
// ctx.MoveTo(x, baseline)
c2 := CloneColor(s.Color)
c2.A = 200
ctx.FillColor(c2)
for i, f := range s.Data {
if i == 0 {
ctx.MoveTo(x+float64(i)*horIncr, baseline-(f*vratio))
}
ctx.LineTo(x+float64(i)*horIncr, baseline-(f*vratio))
if i == len(s.Data)-1 {
ctx.LineTo(x+float64(i)*horIncr, baseline)
ctx.LineTo(x, baseline)
ctx.MoveTo(x, baseline-(s.Data[0]*vratio))
break
}
}
ctx.Fill()
}
}
}