cairo/canvas.go
func (v *Context) InStroke(x, y float64) bool {
	c := C.cairo_in_stroke(v.native(), C.double(x), C.double(y))
	return gobool(c)
}
func (v *Context) InStroke(x, y float64) bool {
	c := C.cairo_in_stroke(v.native(), C.double(x), C.double(y))
	return gobool(c)
}
// InStroke is a wrapper around cairo_in_stroke().