C++ FCOORD类代码示例

// Copies the given feature_space and uses it as the index feature map
// from INT_FEATURE_STRUCT.
void IntFeatureMap::Init(const IntFeatureSpace& feature_space) {
  feature_space_ = feature_space;
  mapping_changed_ = false;
  int sparse_size = feature_space_.Size();
  feature_map_.Init(sparse_size, true);
  feature_map_.Setup();
  compact_size_ = feature_map_.CompactSize();
  // Initialize look-up tables if needed.
  FCOORD dir = FeatureDirection(0);
  if (dir.x() == 0.0f && dir.y() == 0.0f)
    InitIntegerFX();
  // Compute look-up tables to generate offset features.
  for (int dir = 0; dir < kNumOffsetMaps; ++dir) {
    delete [] offset_plus_[dir];
    delete [] offset_minus_[dir];
    offset_plus_[dir] = new int[sparse_size];
    offset_minus_[dir] = new int[sparse_size];
  }
  for (int dir = 1; dir <= kNumOffsetMaps; ++dir) {
    for (int i = 0; i < sparse_size; ++i) {
      int offset_index = ComputeOffsetFeature(i, dir);
      offset_plus_[dir - 1][i] = offset_index;
      offset_index = ComputeOffsetFeature(i, -dir);
      offset_minus_[dir - 1][i] = offset_index;
    }
  }
}

// Rotate the grid by rotation, keeping cell contents.
// rotation must be a multiple of 90 degrees.
// NOTE: due to partial cells, cell coverage in the rotated grid will be
// inexact. This is why there is no Rotate for the generic BBGrid.
// TODO(rays) investigate fixing this inaccuracy by moving the origin after
// rotation.
void IntGrid::Rotate(const FCOORD& rotation) {
  ASSERT_HOST(rotation.x() == 0.0f || rotation.y() == 0.0f);
  ICOORD old_bleft(bleft());
  ICOORD old_tright(tright());
  int old_width = gridwidth();
  int old_height = gridheight();
  TBOX box(bleft(), tright());
  box.rotate(rotation);
  int* old_grid = grid_;
  grid_ = NULL;
  Init(gridsize(), box.botleft(), box.topright());
  // Iterate over the old grid, copying data to the rotated position in the new.
  int oldi = 0;
  FCOORD x_step(rotation);
  x_step *= gridsize();
  for (int oldy = 0; oldy < old_height; ++oldy) {
    FCOORD line_pos(old_bleft.x(), old_bleft.y() + gridsize() * oldy);
    line_pos.rotate(rotation);
    for (int oldx = 0; oldx < old_width; ++oldx, line_pos += x_step, ++oldi) {
      int grid_x, grid_y;
      GridCoords(static_cast<int>(line_pos.x() + 0.5),
                 static_cast<int>(line_pos.y() + 0.5),
                 &grid_x, &grid_y);
      grid_[grid_y * gridwidth() + grid_x] = old_grid[oldi];
    }
  }
  delete [] old_grid;
}

inT16 OUTLINE::winding_number(                     //winding number
                              const FCOORD &point  //point to wind around
                             ) {
  inT16 count;                   //winding count
  POLYPT *polypt;                //current point
  FCOORD vec;                    //to current point
  float cross;                   //cross product
  POLYPT_IT it = &outline;       //iterator

  count = 0;
  do {
    polypt = it.data ();
    vec = polypt->pos - point;
                                 //crossing the line
    if (vec.y () <= 0 && vec.y () + polypt->vec.y () > 0) {
      cross = vec * polypt->vec; //cross product
      if (cross > 0)
        count++;                 //crossing right half
      else if (cross == 0)
        return INTERSECTING;     //going through point
    }
    else if (vec.y () > 0 && vec.y () + polypt->vec.y () <= 0) {
      cross = vec * polypt->vec;
      if (cross < 0)
        count--;                 //crossing back
      else if (cross == 0)
        return INTERSECTING;     //illegal
    }
    it.forward ();
  }
  while (!it.at_first ());
  return count;                  //winding number
}

void DENORM::LocalNormTransform(const FCOORD& pt, FCOORD* transformed) const {
  FCOORD translated(pt.x() - x_origin_, pt.y() - YOriginAtOrigX(pt.x()));
  translated.set_x(translated.x() * x_scale_);
  translated.set_y(translated.y() * YScaleAtOrigX(pt.x()));
  if (rotation_ != NULL)
    translated.rotate(*rotation_);
  transformed->set_x(translated.x() + final_xshift_);
  transformed->set_y(translated.y() + final_yshift_);
}

// Rotates by the given rotation in place.
void TESSLINE::Rotate(const FCOORD rot) {
  EDGEPT* pt = loop;
  do {
    int tmp = static_cast<int>(floor(pt->pos.x * rot.x() -
                                     pt->pos.y * rot.y() + 0.5));
    pt->pos.y = static_cast<int>(floor(pt->pos.y * rot.x() +
                                       pt->pos.x * rot.y() + 0.5));
    pt->pos.x = tmp;
    pt = pt->next;
  } while (pt != loop);
  SetupFromPos();
}

void DENORM::LocalDenormTransform(const FCOORD& pt, FCOORD* original) const {
  FCOORD rotated(pt.x() - final_xshift_, pt.y() - final_yshift_);
  if (rotation_ != NULL) {
    FCOORD inverse_rotation(rotation_->x(), -rotation_->y());
    rotated.rotate(inverse_rotation);
  }
  original->set_x(rotated.x() / x_scale_ + x_origin_);
  float y_scale = y_scale_;
  if (num_segs_ > 0)
    y_scale = YScaleAtOrigX(original->x());
  original->set_y(rotated.y() / y_scale + YOriginAtOrigX(original->x()));
}

// Gathers outline points and their directions from start_index into dirs by
// stepping along the outline and normalizing the coordinates until the
// required feature_length has been collected or end_index is reached.
// On input pos must point to the position corresponding to start_index and on
// return pos is updated to the current raw position, and pos_normed is set to
// the normed version of pos.
// Since directions wrap-around, they need special treatment to get the mean.
// Provided the cluster of directions doesn't straddle the wrap-around point,
// the simple mean works. If they do, then, unless the directions are wildly
// varying, the cluster rotated by 180 degrees will not straddle the wrap-
// around point, so mean(dir + 180 degrees) - 180 degrees will work. Since
// LLSQ conveniently stores the mean of 2 variables, we use it to store
// dir and dir+128 (128 is 180 degrees) and then use the resulting mean
// with the least variance.
static int GatherPoints(const C_OUTLINE* outline, double feature_length,
                        const DENORM& denorm, const DENORM* root_denorm,
                        int start_index, int end_index,
                        ICOORD* pos, FCOORD* pos_normed,
                        LLSQ* points, LLSQ* dirs) {
  int step_length = outline->pathlength();
  ICOORD step = outline->step(start_index % step_length);
  // Prev_normed is the start point of this collection and will be set on the
  // first iteration, and on later iterations used to determine the length
  // that has been collected.
  FCOORD prev_normed;
  points->clear();
  dirs->clear();
  int num_points = 0;
  int index;
  for (index = start_index; index <= end_index; ++index, *pos += step) {
    step = outline->step(index % step_length);
    int edge_weight = outline->edge_strength_at_index(index % step_length);
    if (edge_weight == 0) {
      // This point has conflicting gradient and step direction, so ignore it.
      continue;
    }
    // Get the sub-pixel precise location and normalize.
    FCOORD f_pos = outline->sub_pixel_pos_at_index(*pos, index % step_length);
    denorm.NormTransform(root_denorm, f_pos, pos_normed);
    if (num_points == 0) {
      // The start of this segment.
      prev_normed = *pos_normed;
    } else {
      FCOORD offset = *pos_normed - prev_normed;
      float length = offset.length();
      if (length > feature_length) {
        // We have gone far enough from the start. We will use this point in
        // the next set so return what we have so far.
        return index;
      }
    }
    points->add(pos_normed->x(), pos_normed->y(), edge_weight);
    int direction = outline->direction_at_index(index % step_length);
    if (direction >= 0) {
      direction = NormalizeDirection(direction, f_pos, denorm, root_denorm);
      // Use both the direction and direction +128 so we are not trying to
      // take the mean of something straddling the wrap-around point.
      dirs->add(direction, Modulo(direction + 128, 256));
    }
    ++num_points;
  }
  return index;
}

void DENORM::LocalNormTransform(const FCOORD& pt, FCOORD* transformed) const {
  FCOORD translated(pt.x() - x_origin_, pt.y() - y_origin_);
  if (x_map_ != NULL && y_map_ != NULL) {
    int x = ClipToRange(IntCastRounded(translated.x()), 0, x_map_->size()-1);
    translated.set_x((*x_map_)[x]);
    int y = ClipToRange(IntCastRounded(translated.y()), 0, y_map_->size()-1);
    translated.set_y((*y_map_)[y]);
  } else {
    translated.set_x(translated.x() * x_scale_);
    translated.set_y(translated.y() * y_scale_);
    if (rotation_ != NULL)
      translated.rotate(*rotation_);
  }
  transformed->set_x(translated.x() + final_xshift_);
  transformed->set_y(translated.y() + final_yshift_);
}

// Inserts a list of blobs into the projection.
// Rotation is a multiple of 90 degrees to get from blob coords to
// nontext_map coords, nontext_map_box is the bounds of the nontext_map.
// Blobs are spread horizontally or vertically according to their internal
// flags, but the spreading is truncated by set pixels in the nontext_map
// and also by the horizontal rule line limits on the blobs.
void TextlineProjection::ProjectBlobs(BLOBNBOX_LIST* blobs,
                                      const FCOORD& rotation,
                                      const TBOX& nontext_map_box,
                                      Pix* nontext_map) {
  BLOBNBOX_IT blob_it(blobs);
  for (blob_it.mark_cycle_pt(); !blob_it.cycled_list(); blob_it.forward()) {
    BLOBNBOX* blob = blob_it.data();
    TBOX bbox = blob->bounding_box();
    ICOORD middle((bbox.left() + bbox.right()) / 2,
                  (bbox.bottom() + bbox.top()) / 2);
    bool spreading_horizontally = PadBlobBox(blob, &bbox);
    // Rotate to match the nontext_map.
    bbox.rotate(rotation);
    middle.rotate(rotation);
    if (rotation.x() == 0.0f)
      spreading_horizontally = !spreading_horizontally;
    // Clip to the image before applying the increments.
    bbox &= nontext_map_box;  // This is in-place box intersection.
    // Check for image pixels before spreading.
    TruncateBoxToMissNonText(middle.x(), middle.y(), spreading_horizontally,
                             nontext_map, &bbox);
    if (bbox.area() > 0) {
      IncrementRectangle8Bit(bbox);
    }
  }
}

void DENORM::LocalDenormTransform(const FCOORD& pt, FCOORD* original) const {
  FCOORD rotated(pt.x() - final_xshift_, pt.y() - final_yshift_);
  if (x_map_ != NULL && y_map_ != NULL) {
    int x = x_map_->binary_search(rotated.x());
    original->set_x(x + x_origin_);
    int y = y_map_->binary_search(rotated.y());
    original->set_y(y + y_origin_);
  } else {
    if (rotation_ != NULL) {
      FCOORD inverse_rotation(rotation_->x(), -rotation_->y());
      rotated.rotate(inverse_rotation);
    }
    original->set_x(rotated.x() / x_scale_ + x_origin_);
    float y_scale = y_scale_;
    original->set_y(rotated.y() / y_scale + y_origin_);
  }
}

void PageIterator::Orientation(tesseract::Orientation *orientation,
                               tesseract::WritingDirection *writing_direction,
                               tesseract::TextlineOrder *textline_order,
                               float *deskew_angle) const {
  BLOCK* block = it_->block()->block;

  // Orientation
  FCOORD up_in_image(0.0, 1.0);
  up_in_image.unrotate(block->classify_rotation());
  up_in_image.rotate(block->re_rotation());

  if (up_in_image.x() == 0.0F) {
    if (up_in_image.y() > 0.0F) {
      *orientation = ORIENTATION_PAGE_UP;
    } else {
      *orientation = ORIENTATION_PAGE_DOWN;
    }
  } else if (up_in_image.x() > 0.0F) {
    *orientation = ORIENTATION_PAGE_RIGHT;
  } else {
    *orientation = ORIENTATION_PAGE_LEFT;
  }

  // Writing direction
  bool is_vertical_text = (block->classify_rotation().x() == 0.0);
  bool right_to_left = block->right_to_left();
  *writing_direction =
      is_vertical_text
          ? WRITING_DIRECTION_TOP_TO_BOTTOM
          : (right_to_left
                ? WRITING_DIRECTION_RIGHT_TO_LEFT
                : WRITING_DIRECTION_LEFT_TO_RIGHT);

  // Textline Order
  bool is_mongolian = false;  // TODO(eger): fix me
  *textline_order = is_vertical_text
      ? (is_mongolian
         ? TEXTLINE_ORDER_LEFT_TO_RIGHT
         : TEXTLINE_ORDER_RIGHT_TO_LEFT)
      : TEXTLINE_ORDER_TOP_TO_BOTTOM;

  // Deskew angle
  FCOORD skew = block->skew();  // true horizontal for textlines
  *deskew_angle = -skew.angle();
}

// Fits a line in the given direction to blobs that are close to the given
// target_offset perpendicular displacement from the direction. The fit
// error is allowed to be cheat_allowance worse than the existing fit, and
// will still be used.
// If cheat_allowance > 0, the new fit will be good and replace the current
// fit if it has better fit (with cheat) OR its error is below
// max_baseline_error_ and the old fit is marked bad.
// Otherwise the new fit will only replace the old if it is really better,
// or the old fit is marked bad and the new fit has sufficient points, as
// well as being within the max_baseline_error_.
void BaselineRow::FitConstrainedIfBetter(int debug,
                                         const FCOORD& direction,
                                         double cheat_allowance,
                                         double target_offset) {
  double halfrange = fit_halfrange_ * direction.length();
  double min_dist = target_offset - halfrange;
  double max_dist = target_offset + halfrange;
  ICOORD line_pt;
  double new_error = fitter_.ConstrainedFit(direction, min_dist, max_dist,
                                            debug > 2, &line_pt);
  // Allow cheat_allowance off the new error
  new_error -= cheat_allowance;
  double old_angle = BaselineAngle();
  double new_angle = direction.angle();
  if (debug > 1) {
    tprintf("Constrained error = %g, original = %g",
            new_error, baseline_error_);
    tprintf(" angles = %g, %g, delta=%g vs threshold %g\n",
            old_angle, new_angle,
            new_angle - old_angle, kMaxSkewDeviation);
  }
  bool new_good_baseline = new_error <= max_baseline_error_ &&
      (cheat_allowance > 0.0 || fitter_.SufficientPointsForIndependentFit());
  // The new will replace the old if any are true:
  // 1. the new error is better
  // 2. the old is NOT good, but the new is
  // 3. there is a wild angular difference between them (assuming that the new
  //    is a better guess at the angle.)
  if (new_error <= baseline_error_ ||
      (!good_baseline_ && new_good_baseline) ||
      fabs(new_angle - old_angle) > kMaxSkewDeviation) {
    baseline_error_ = new_error;
    baseline_pt1_ = line_pt;
    baseline_pt2_ = baseline_pt1_ + direction;
    good_baseline_ = new_good_baseline;
    if (debug > 1) {
      tprintf("Replacing with constrained baseline, good = %d\n",
              good_baseline_);
    }
  } else if (debug > 1) {
    tprintf("Keeping old baseline\n");
  }
}

// Returns the point on the given line nearest to this, ie the point such
// that the vector point->this is perpendicular to the line.
// The line is defined as a line_point and a dir_vector for its direction.
FCOORD FCOORD::nearest_pt_on_line(const FCOORD& line_point,
                                  const FCOORD& dir_vector) const {
  FCOORD point_vector(*this - line_point);
  // The dot product (%) is |dir_vector||point_vector|cos theta, so dividing by
  // the square of the length of dir_vector gives us the fraction of dir_vector
  // to add to line1 to get the appropriate point, so
  // result = line1 + lambda dir_vector.
  double lambda = point_vector % dir_vector / dir_vector.sqlength();
  return line_point + (dir_vector * lambda);
}

void OUTLINE::move(                  // reposition OUTLINE
                   const FCOORD vec  // by vector
                  ) {
                                 //child outline itertr
  OUTLINE_IT child_it(&children);
  POLYPT_IT poly_it(&outline);  //outline point itertr

  box.move (vec);

  start.set_x ((inT16) floor (start.x () + vec.x () + 0.5));
  // ?? Why ICOORD?
  start.set_y ((inT16) floor (start.y () + vec.y () + 0.5));
  // ?? Why ICOORD?

  for (poly_it.mark_cycle_pt (); !poly_it.cycled_list (); poly_it.forward ())
    poly_it.data ()->pos += vec;

  for (child_it.mark_cycle_pt (); !child_it.cycled_list ();
    child_it.forward ())
  child_it.data ()->move (vec);  // move child outlines
}

void OUTLINE::scale(                     // scale OUTLINE
                    const FCOORD vector  //by fcoord
                   ) {
                                 //child outline itertr
  OUTLINE_IT child_it(&children);
  POLYPT_IT poly_it(&outline);  //outline point itertr
  POLYPT *pt;

  box.scale (vector);

  start.set_x ((inT16) floor (start.x () * vector.x () + 0.5));
  // ?? Why ICOORD?
  start.set_y ((inT16) floor (start.y () * vector.y () + 0.5));
  // ?? Why ICOORD?

  for (poly_it.mark_cycle_pt (); !poly_it.cycled_list (); poly_it.forward ()) {
    pt = poly_it.data ();
    pt->pos =
      FCOORD (pt->pos.x () * vector.x (), pt->pos.y () * vector.y ());
    pt->vec =
      FCOORD (pt->vec.x () * vector.x (), pt->vec.y () * vector.y ());
  }

  for (child_it.mark_cycle_pt (); !child_it.cycled_list ();
    child_it.forward ())
                                 //scale child outlines
  child_it.data ()->scale (vector);
}