/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * Copyright 2011, Blender Foundation.
 */

#include "COM_DotproductOperation.h"

namespace blender::compositor {

DotproductOperation::DotproductOperation()
{
  this->add_input_socket(DataType::Vector);
  this->add_input_socket(DataType::Vector);
  this->add_output_socket(DataType::Value);
  this->set_canvas_input_index(0);
  input1Operation_ = nullptr;
  input2Operation_ = nullptr;
  flags_.can_be_constant = true;
}
void DotproductOperation::init_execution()
{
  input1Operation_ = this->get_input_socket_reader(0);
  input2Operation_ = this->get_input_socket_reader(1);
}

void DotproductOperation::deinit_execution()
{
  input1Operation_ = nullptr;
  input2Operation_ = nullptr;
}

/** \todo current implementation is the inverse of a dot-product. not 'logically' correct
 */
void DotproductOperation::execute_pixel_sampled(float output[4],
                                                float x,
                                                float y,
                                                PixelSampler sampler)
{
  float input1[4];
  float input2[4];
  input1Operation_->read_sampled(input1, x, y, sampler);
  input2Operation_->read_sampled(input2, x, y, sampler);
  output[0] = -(input1[0] * input2[0] + input1[1] * input2[1] + input1[2] * input2[2]);
}

void DotproductOperation::update_memory_buffer_partial(MemoryBuffer *output,
                                                       const rcti &area,
                                                       Span<MemoryBuffer *> inputs)
{
  for (BuffersIterator<float> it = output->iterate_with(inputs, area); !it.is_end(); ++it) {
    const float *input1 = it.in(0);
    const float *input2 = it.in(1);
    *it.out = -(input1[0] * input2[0] + input1[1] * input2[1] + input1[2] * input2[2]);
  }
}

}  // namespace blender::compositor