pub unsafe extern "C" fn gtk_snapshot_append_radial_gradient(
    snapshot: *mut GtkSnapshot,
    bounds: *const graphene_rect_t,
    center: *const graphene_point_t,
    hradius: c_float,
    vradius: c_float,
    start: c_float,
    end: c_float,
    stops: *const GskColorStop,
    n_stops: size_t
)