// ArcNegative draws an arc with a negative angle (anti clockwise).
func ArcNegative(gc draw2d.GraphicContext, xc, yc, width, height float64) {
xc += width / 2
yc += height / 2
radiusX, radiusY := width/2, height/2
startAngle := 45.0 * (math.Pi / 180.0) /* angles are specified */
angle := -225 * (math.Pi / 180.0) /* clockwise in radians */
gc.SetLineWidth(width / 10)
gc.SetLineCap(draw2d.ButtCap)
gc.SetStrokeColor(image.Black)
gc.ArcTo(xc, yc, radiusX, radiusY, startAngle, angle)
gc.Stroke()
// fill a circle
gc.SetStrokeColor(color.NRGBA{255, 0x33, 0x33, 0x80})
gc.SetFillColor(color.NRGBA{255, 0x33, 0x33, 0x80})
gc.SetLineWidth(width / 20)
gc.MoveTo(xc+math.Cos(startAngle)*radiusX, yc+math.Sin(startAngle)*radiusY)
gc.LineTo(xc, yc)
gc.LineTo(xc-radiusX, yc)
gc.Stroke()
gc.ArcTo(xc, yc, width/10.0, height/10.0, 0, 2*math.Pi)
gc.Fill()
}
// Draw a gopher head (not rotated)
func Draw(gc draw2d.GraphicContext, x, y, w, h float64) {
h23 := (h * 2) / 3
blf := color.RGBA{0, 0, 0, 0xff} // black
wf := color.RGBA{0xff, 0xff, 0xff, 0xff} // white
nf := color.RGBA{0x8B, 0x45, 0x13, 0xff} // brown opaque
brf := color.RGBA{0x8B, 0x45, 0x13, 0x99} // brown transparant
brb := color.RGBA{0x8B, 0x45, 0x13, 0xBB} // brown transparant
// round head top
gc.MoveTo(x, y+h*1.002)
gc.CubicCurveTo(x+w/4, y-h/3, x+3*w/4, y-h/3, x+w, y+h*1.002)
gc.Close()
gc.SetFillColor(brb)
gc.Fill()
// rectangle head bottom
draw2dkit.RoundedRectangle(gc, x, y+h, x+w, y+h+h, h/5, h/5)
gc.Fill()
// left ear outside
draw2dkit.Circle(gc, x, y+h, w/12)
gc.SetFillColor(brf)
gc.Fill()
// left ear inside
draw2dkit.Circle(gc, x, y+h, 0.5*w/12)
gc.SetFillColor(nf)
gc.Fill()
// right ear outside
draw2dkit.Circle(gc, x+w, y+h, w/12)
gc.SetFillColor(brf)
gc.Fill()
// right ear inside
draw2dkit.Circle(gc, x+w, y+h, 0.5*w/12)
gc.SetFillColor(nf)
gc.Fill()
// left eye outside white
draw2dkit.Circle(gc, x+w/3, y+h23, w/9)
gc.SetFillColor(wf)
gc.Fill()
// left eye black
draw2dkit.Circle(gc, x+w/3+w/24, y+h23, 0.5*w/9)
gc.SetFillColor(blf)
gc.Fill()
// left eye inside white
draw2dkit.Circle(gc, x+w/3+w/24+w/48, y+h23, 0.2*w/9)
gc.SetFillColor(wf)
gc.Fill()
// right eye outside white
draw2dkit.Circle(gc, x+w-w/3, y+h23, w/9)
gc.Fill()
// right eye black
draw2dkit.Circle(gc, x+w-w/3+w/24, y+h23, 0.5*w/9)
gc.SetFillColor(blf)
gc.Fill()
// right eye inside white
draw2dkit.Circle(gc, x+w-(w/3)+w/24+w/48, y+h23, 0.2*w/9)
gc.SetFillColor(wf)
gc.Fill()
// left tooth
gc.SetFillColor(wf)
draw2dkit.RoundedRectangle(gc, x+w/2-w/8, y+h+h/2.5, x+w/2-w/8+w/8, y+h+h/2.5+w/6, w/10, w/10)
gc.Fill()
// right tooth
draw2dkit.RoundedRectangle(gc, x+w/2, y+h+h/2.5, x+w/2+w/8, y+h+h/2.5+w/6, w/10, w/10)
gc.Fill()
// snout
draw2dkit.Ellipse(gc, x+(w/2), y+h+h/2.5, w/6, w/12)
gc.SetFillColor(nf)
gc.Fill()
// nose
draw2dkit.Ellipse(gc, x+(w/2), y+h+h/7, w/10, w/12)
gc.SetFillColor(blf)
gc.Fill()
}