draw2dpdf/gc.go
func (gc *GraphicContext) SetLineCap(Cap draw2d.LineCap) {
	gc.StackGraphicContext.SetLineCap(Cap)
	gc.pdf.SetLineCapStyle(caps[Cap])
}
func (gc *GraphicContext) SetLineCap(Cap draw2d.LineCap) {
	gc.StackGraphicContext.SetLineCap(Cap)
	gc.pdf.SetLineCapStyle(caps[Cap])
}
// SetLineCap sets the line cap (round, but or square)