cairo/canvas.go
func (v *Context) GetDash() (dashes []float64, offset float64) {
	dashCount := v.GetDashCount()
	cdashes := (*C.double)(C.calloc(8, C.size_t(dashCount)))
	var coffset C.double
	C.cairo_get_dash(v.native(), cdashes, &coffset)
	header := (*reflect.SliceHeader)((unsafe.Pointer(&dashes)))
	header.Data = uintptr(unsafe.Pointer(cdashes))
	header.Len = dashCount
	header.Cap = dashCount
	return dashes, float64(coffset)
}
func (v *Context) GetDash() (dashes []float64, offset float64) {
	dashCount := v.GetDashCount()
	cdashes := (*C.double)(C.calloc(8, C.size_t(dashCount)))
	var coffset C.double
	C.cairo_get_dash(v.native(), cdashes, &coffset)
	header := (*reflect.SliceHeader)((unsafe.Pointer(&dashes)))
	header.Data = uintptr(unsafe.Pointer(cdashes))
	header.Len = dashCount
	header.Cap = dashCount
	return dashes, float64(coffset)
}
// GetDash is a wrapper around cairo_get_dash().