func (ig *ImageGraphics) setStyle(style chart.Style) {
ig.gc.SetStrokeColor(chart.Color2RGBA(style.LineColor, 0xff))
ig.gc.SetLineWidth(float64(style.LineWidth))
orig := dashPattern[style.LineStyle]
pattern := make([]float64, len(orig))
copy(pattern, orig)
for i := range pattern {
pattern[i] *= math.Sqrt(float64(style.LineWidth))
}
ig.gc.SetLineDash(pattern, 0)
}
func (ig *ImageGraphics) Rect(x, y, w, h int, style chart.Style) {
ig.setStyle(style)
stroke := func() { ig.gc.Stroke() }
if style.FillColor != "" {
ig.gc.SetFillColor(chart.Color2RGBA(style.FillColor, 0x0ff /*uint8(style.Alpha*255)*/))
stroke = func() { ig.gc.FillStroke() }
}
ig.gc.MoveTo(float64(x), float64(y))
ig.gc.LineTo(float64(x+w), float64(y))
ig.gc.LineTo(float64(x+w), float64(y+h))
ig.gc.LineTo(float64(x), float64(y+h))
ig.gc.LineTo(float64(x), float64(y))
stroke()
}
func (ig *ImageGraphics) Wedge(ix, iy, iro, iri int, phi, psi float64, style chart.Style) {
ig.setStyle(style)
stroke := func() { ig.gc.Stroke() }
if style.FillColor != "" {
ig.gc.SetFillColor(chart.Color2RGBA(style.FillColor, 0x0ff /*uint8(style.Alpha*255)*/))
stroke = func() { ig.gc.FillStroke() }
}
iri = 0
ecc := 1.0 // eccentricity
x, y := float64(ix), float64(iy) // center as float
ro, ri := float64(iro), float64(iri) // radius outer and inner as float
roe, rie := ro*ecc, ri*ecc // inner and outer radius corrected by ecc
xao, yao := math.Cos(phi)*roe+x, y+math.Sin(phi)*ro
// xco, yco := math.Cos(psi)*roe+x, y-math.Sin(psi)*ro
xai, yai := math.Cos(phi)*rie+x, y+math.Sin(phi)*ri
xci, yci := math.Cos(psi)*rie+x, y+math.Sin(psi)*ri
// outbound straight line
if ri > 0 {
ig.gc.MoveTo(xai, yai)
} else {
ig.gc.MoveTo(x, y)
}
ig.gc.LineTo(xao, yao)
// outer arc
ig.gc.ArcTo(x, y, ro, roe, phi, psi-phi)
// inbound straight line
if ri > 0 {
ig.gc.LineTo(xci, yci)
ig.gc.ArcTo(x, y, ri, rie, psi, phi-psi)
} else {
ig.gc.LineTo(x, y)
}
stroke()
}
func (ig *ImageGraphics) setStyle(style chart.Style) {
ig.gc.SetStrokeColor(chart.Color2RGBA(style.LineColor, 0xff))
ig.gc.SetLineWidth(float64(style.LineWidth))
ig.gc.SetLineDash(dashPattern[style.LineStyle], 0)
}