code: func NewPatternRadial(x0, y0, r0, x1, y1, r1 float64) (*Pattern, error) {
  	c := C.cairo_pattern_create_radial(C.double(x0), C.double(y0), C.double(r0),
  		C.double(x1), C.double(y1), C.double(r1))
  	return newPatternFromNative(c)
  }
docs: // NewPatternRadial is a wrapper around cairo_pattern_create_radial().