zinnia feature.cpp

## zinnia feature.cpp
// zinniaの特徴量抽出は以下を参照

void Features::makeBasicFeature(int offset,
                                const Node *first,
                                const Node *last) {
  // distance
  addFeature(offset + 1 , 10 * distance(first, last));

  // degree
  addFeature(offset + 2 ,
             std::atan2(last->y - first->y, last->x - first->x));

  // absolute position
  addFeature(offset + 3, 10 * (first->x - 0.5));
  addFeature(offset + 4, 10 * (first->y - 0.5));
  addFeature(offset + 5, 10 * (last->x - 0.5));
  addFeature(offset + 6, 10 * (last->y - 0.5));

  // absolute degree
  addFeature(offset + 7, std::atan2(first->y - 0.5, first->x - 0.5));
  addFeature(offset + 8, std::atan2(last->y - 0.5,  last->x - 0.5));

  // absolute distance
  addFeature(offset + 9,  10 * distance2(first));
  addFeature(offset + 10, 10 * distance2(last));

  // diff
  addFeature(offset + 11, 5 * (last->x - first->x));
  addFeature(offset + 12, 5 * (last->y - first->y));
}