func (h *spaceFillingImage) drawSnake(gc draw2d.GraphicContext, snake *draw2d.Path) {
gc.SetStrokeColor(h.SnakeColor)
gc.SetLineCap(draw2d.SquareCap)
gc.SetLineJoin(draw2d.MiterJoin)
gc.SetLineWidth(2)
gc.Stroke(snake)
}
// Dash draws a line with a dash pattern
func Dash(gc draw2d.GraphicContext, x, y, width, height float64) {
sx, sy := width/162, height/205
gc.SetStrokeColor(image.Black)
gc.SetLineDash([]float64{height / 10, height / 50, height / 50, height / 50}, -50.0)
gc.SetLineCap(draw2d.ButtCap)
gc.SetLineJoin(draw2d.RoundJoin)
gc.SetLineWidth(height / 50)
gc.MoveTo(x+sx*60.0, y)
gc.LineTo(x+sx*60.0, y)
gc.LineTo(x+sx*162, y+sy*205)
gc.RLineTo(sx*-102.4, 0.0)
gc.CubicCurveTo(x+sx*-17, y+sy*205, x+sx*-17, y+sy*103, x+sx*60.0, y+sy*103.0)
gc.Stroke()
gc.SetLineDash(nil, 0.0)
}
// Draw a line with an angle with specified line cap and join
func Draw(gc draw2d.GraphicContext, cap draw2d.Cap, join draw2d.Join,
x0, y0, x1, y1, offset float64) {
gc.SetLineCap(cap)
gc.SetLineJoin(join)
// Draw thick line
gc.SetStrokeColor(color.NRGBA{0x33, 0x33, 0x33, 0xFF})
gc.SetLineWidth(30.0)
gc.MoveTo(x0, y0)
gc.LineTo((x0+x1)/2+offset, (y0+y1)/2)
gc.LineTo(x1, y1)
gc.Stroke()
// Draw thin helping line
gc.SetStrokeColor(color.NRGBA{0xFF, 0x33, 0x33, 0xFF})
gc.SetLineWidth(2.56)
gc.MoveTo(x0, y0)
gc.LineTo((x0+x1)/2+offset, (y0+y1)/2)
gc.LineTo(x1, y1)
gc.Stroke()
}