draw2dimg/ftgc.go
func (gc *GraphicContext) Stroke(paths ...*draw2d.Path) {
	paths = append(paths, gc.Current.Path)
	gc.strokeRasterizer.UseNonZeroWinding = true

	stroker := draw2dbase.NewLineStroker(gc.Current.Cap, gc.Current.Join, draw2dbase.Transformer{Tr: gc.Current.Tr, Flattener: FtLineBuilder{Adder: gc.strokeRasterizer}})
	stroker.HalfLineWidth = gc.Current.LineWidth / 2

	var liner draw2dbase.Flattener
	if gc.Current.Dash != nil && len(gc.Current.Dash) > 0 {
		liner = draw2dbase.NewDashConverter(gc.Current.Dash, gc.Current.DashOffset, stroker)
	} else {
		liner = stroker
	}
	for _, p := range paths {
		draw2dbase.Flatten(p, liner, gc.Current.Tr.GetScale())
	}

	gc.paint(gc.strokeRasterizer, gc.Current.StrokeColor)
}
func (gc *GraphicContext) Stroke(paths ...*draw2d.Path) {
	paths = append(paths, gc.Current.Path)
	gc.strokeRasterizer.UseNonZeroWinding = true

	stroker := draw2dbase.NewLineStroker(gc.Current.Cap, gc.Current.Join, draw2dbase.Transformer{Tr: gc.Current.Tr, Flattener: FtLineBuilder{Adder: gc.strokeRasterizer}})
	stroker.HalfLineWidth = gc.Current.LineWidth / 2

	var liner draw2dbase.Flattener
	if gc.Current.Dash != nil && len(gc.Current.Dash) > 0 {
		liner = draw2dbase.NewDashConverter(gc.Current.Dash, gc.Current.DashOffset, stroker)
	} else {
		liner = stroker
	}
	for _, p := range paths {
		draw2dbase.Flatten(p, liner, gc.Current.Tr.GetScale())
	}

	gc.paint(gc.strokeRasterizer, gc.Current.StrokeColor)
}
// Stroke strokes the paths with the color specified by SetStrokeColor