def METHOD_NAME(self, ray_bundle: RayBundle) -> Dict:
    ray_samples = self.sampler(ray_bundle, sdf_fn=self.field.get_sdf)
    # save_points("a.ply", ray_samples.frustums.get_start_positions().reshape(-1, 3).detach().cpu().numpy())
    field_outputs = self.field(ray_samples, return_alphas=True)
    weights, transmittance = ray_samples.get_weights_and_transmittance_from_alphas(
        field_outputs[FieldHeadNames.ALPHA]
    )
    bg_transmittance = transmittance[:, -1, :]
    samples_and_field_outputs = {
        "ray_samples": ray_samples,
        "field_outputs": field_outputs,
        "weights": weights,
        "bg_transmittance": bg_transmittance,
    }
    return samples_and_field_outputs