/******************************************************************************
 * Copyright 2020 The Apollo Authors. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *****************************************************************************/

/*
 * Copyright 2018-2019 Autoware Foundation. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @file scatter_cuda.h
 * @brief CUDA code for scatter operation
 * @author Kosuke Murakami
 * @date 2019/02/26
 */

#pragma once

namespace apollo {
namespace perception {
namespace lidar {

class ScatterCuda {
 private:
  const int num_threads_;
  const int grid_x_size_;
  const int grid_y_size_;

 public:
  /**
   * @brief Constructor
   * @param[in] num_threads The number of threads to launch cuda kernel
   * @param[in] grid_x_size Number of pillars in x-coordinate
   * @param[in] grid_y_size Number of pillars in y-coordinate
   * @details Captital variables never change after the compile
   */
  ScatterCuda(const int num_threads, const int grid_x_size,
              const int grid_y_size);

  /**
   * @brief Call scatter cuda kernel
   * @param[in] pillar_count The valid number of pillars
   * @param[in] x_coors X-coordinate indexes for corresponding pillars
   * @param[in] y_coors Y-coordinate indexes for corresponding pillars
   * @param[in] pfe_output Output from Pillar Feature Extractor
   * @param[out] scattered_feature Gridmap representation for pillars' feature
   * @details Allocate pillars in gridmap based on index(coordinates)
   * information
   */
  void DoScatterCuda(const int pillar_count, int* x_coors, int* y_coors,
                     float* pfe_output, float* scattered_feature);
};

}  // namespace lidar
}  // namespace perception
}  // namespace apollo