// Return true if this vector is the same side, overlaps, and close
// enough to the other to be merged.
bool TabVector::SimilarTo(const ICOORD& vertical,
const TabVector& other, BlobGrid* grid) const {
if ((IsRightTab() && other.IsRightTab()) ||
(IsLeftTab() && other.IsLeftTab())) {
// If they don't overlap, at least in extensions, then there is no chance.
if (ExtendedOverlap(other.extended_ymax_, other.extended_ymin_) < 0)
return false;
// A fast approximation to the scale factor of the sort_key_.
int v_scale = abs(vertical.y());
if (v_scale == 0)
v_scale = 1;
// If they are close enough, then OK.
if (sort_key_ + kSimilarVectorDist * v_scale >= other.sort_key_ &&
sort_key_ - kSimilarVectorDist * v_scale <= other.sort_key_)
return true;
// Ragged tabs get a bigger threshold.
if (!IsRagged() || !other.IsRagged() ||
sort_key_ + kSimilarRaggedDist * v_scale < other.sort_key_ ||
sort_key_ - kSimilarRaggedDist * v_scale > other.sort_key_)
return false;
if (grid == NULL) {
// There is nothing else to test!
return true;
}
// If there is nothing in the rectangle between the vector that is going to
// move, and the place it is moving to, then they can be merged.
// Setup a vertical search for any blob.
const TabVector* mover = (IsRightTab() &&
sort_key_ < other.sort_key_) ? this : &other;
int top_y = mover->endpt_.y();
int bottom_y = mover->startpt_.y();
int left = MIN(mover->XAtY(top_y), mover->XAtY(bottom_y));
int right = MAX(mover->XAtY(top_y), mover->XAtY(bottom_y));
int shift = abs(sort_key_ - other.sort_key_) / v_scale;
if (IsRightTab()) {
right += shift;
} else {
left -= shift;
}
GridSearch<BLOBNBOX, BLOBNBOX_CLIST, BLOBNBOX_C_IT> vsearch(grid);
vsearch.StartVerticalSearch(left, right, top_y);
BLOBNBOX* blob;
while ((blob = vsearch.NextVerticalSearch(true)) != NULL) {
TBOX box = blob->bounding_box();
if (box.top() > bottom_y)
return true; // Nothing found.
if (box.bottom() < top_y)
continue; // Doesn't overlap.
int left_at_box = XAtY(box.bottom());
int right_at_box = left_at_box;
if (IsRightTab())
right_at_box += shift;
else
left_at_box -= shift;
if (MIN(right_at_box, box.right()) > MAX(left_at_box, box.left()))
return false;
}
return true; // Nothing found.
}
return false;
}
