rect.cpp

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/**********************************************************************
 * File:        rect.cpp  (Formerly box.c)
 * Description: Bounding box class definition.
 * Author:      Phil Cheatle
 *
 * (C) Copyright 1991, Hewlett-Packard Ltd.
 ** 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.
 *
 **********************************************************************/
 
// Include automatically generated configuration file if running autoconf.
#ifdef HAVE_CONFIG_H
#  include "config_auto.h"
#endif
 
#include "rect.h"
 
#include "serialis.h" // for TFile
 
namespace tesseract {
 
/**********************************************************************
 * TBOX::TBOX()  Constructor from 2 ICOORDS
 *
 **********************************************************************/
 
TBOX::TBOX(           // constructor
    const ICOORD pt1, // one corner
    const ICOORD pt2  // the other corner
) {
  if (pt1.x() <= pt2.x()) {
    if (pt1.y() <= pt2.y()) {
      bot_left = pt1;
      top_right = pt2;
    } else {
      bot_left = ICOORD(pt1.x(), pt2.y());
      top_right = ICOORD(pt2.x(), pt1.y());
    }
  } else {
    if (pt1.y() <= pt2.y()) {
      bot_left = ICOORD(pt2.x(), pt1.y());
      top_right = ICOORD(pt1.x(), pt2.y());
    } else {
      bot_left = pt2;
      top_right = pt1;
    }
  }
}
 
bool TBOX::DeSerialize(TFile *f) {
  return bot_left.DeSerialize(f) && top_right.DeSerialize(f);
}
 
bool TBOX::Serialize(TFile *f) const {
  return bot_left.Serialize(f) && top_right.Serialize(f);
}
 
// rotate_large constructs the containing bounding box of all 4
// corners after rotating them. It therefore guarantees that all
// original content is contained within, but also slightly enlarges the box.
void TBOX::rotate_large(const FCOORD &vec) {
  ICOORD top_left(bot_left.x(), top_right.y());
  ICOORD bottom_right(top_right.x(), bot_left.y());
  top_left.rotate(vec);
  bottom_right.rotate(vec);
  rotate(vec);
  TBOX box2(top_left, bottom_right);
  *this += box2;
}
 
/**********************************************************************
 * TBOX::intersection()  Build the largest box contained in both boxes
 *
 **********************************************************************/
 
TBOX TBOX::intersection( // shared area box
    const TBOX &box) const {
  TDimension left;
  TDimension bottom;
  TDimension right;
  TDimension top;
  if (overlap(box)) {
    if (box.bot_left.x() > bot_left.x()) {
      left = box.bot_left.x();
    } else {
      left = bot_left.x();
    }
 
    if (box.top_right.x() < top_right.x()) {
      right = box.top_right.x();
    } else {
      right = top_right.x();
    }
 
    if (box.bot_left.y() > bot_left.y()) {
      bottom = box.bot_left.y();
    } else {
      bottom = bot_left.y();
    }
 
    if (box.top_right.y() < top_right.y()) {
      top = box.top_right.y();
    } else {
      top = top_right.y();
    }
  } else {
    left = INT16_MAX;
    bottom = INT16_MAX;
    top = -INT16_MAX;
    right = -INT16_MAX;
  }
  return TBOX(left, bottom, right, top);
}
 
/**********************************************************************
 * TBOX::bounding_union()  Build the smallest box containing both boxes
 *
 **********************************************************************/
 
TBOX TBOX::bounding_union( // box enclosing both
    const TBOX &box) const {
  ICOORD bl; // bottom left
  ICOORD tr; // top right
 
  if (box.bot_left.x() < bot_left.x()) {
    bl.set_x(box.bot_left.x());
  } else {
    bl.set_x(bot_left.x());
  }
 
  if (box.top_right.x() > top_right.x()) {
    tr.set_x(box.top_right.x());
  } else {
    tr.set_x(top_right.x());
  }
 
  if (box.bot_left.y() < bot_left.y()) {
    bl.set_y(box.bot_left.y());
  } else {
    bl.set_y(bot_left.y());
  }
 
  if (box.top_right.y() > top_right.y()) {
    tr.set_y(box.top_right.y());
  } else {
    tr.set_y(top_right.y());
  }
  return TBOX(bl, tr);
}
 
/**********************************************************************
 * TBOX::plot()  Paint a box using specified settings
 *
 **********************************************************************/
 
#ifndef GRAPHICS_DISABLED
void TBOX::plot(                    // paint box
    ScrollView *fd,                 // where to paint
    ScrollView::Color fill_colour,  // colour for inside
    ScrollView::Color border_colour // colour for border
    ) const {
  fd->Brush(fill_colour);
  fd->Pen(border_colour);
  plot(fd);
}
#endif
 
// Appends the bounding box as (%d,%d)->(%d,%d) to a string.
void TBOX::print_to_str(std::string &str) const {
  // "(%d,%d)->(%d,%d)", left(), bottom(), right(), top()
  str += "(" + std::to_string(left());
  str += "," + std::to_string(bottom());
  str += ")->(" + std::to_string(right());
  str += "," + std::to_string(top());
  str += ')';
}
 
// Writes to the given file. Returns false in case of error.
bool TBOX::Serialize(FILE *fp) const {
  if (!bot_left.Serialize(fp)) {
    return false;
  }
  if (!top_right.Serialize(fp)) {
    return false;
  }
  return true;
}
// Reads from the given file. Returns false in case of error.
// If swap is true, assumes a big/little-endian swap is needed.
bool TBOX::DeSerialize(bool swap, FILE *fp) {
  if (!bot_left.DeSerialize(swap, fp)) {
    return false;
  }
  if (!top_right.DeSerialize(swap, fp)) {
    return false;
  }
  return true;
}
 
/**********************************************************************
 * operator+=
 *
 * Extend one box to include the other  (In place union)
 **********************************************************************/
 
TBOX &operator+=( // bounding bounding bx
    TBOX &op1,    // operands
    const TBOX &op2) {
  if (op2.bot_left.x() < op1.bot_left.x()) {
    op1.bot_left.set_x(op2.bot_left.x());
  }
 
  if (op2.top_right.x() > op1.top_right.x()) {
    op1.top_right.set_x(op2.top_right.x());
  }
 
  if (op2.bot_left.y() < op1.bot_left.y()) {
    op1.bot_left.set_y(op2.bot_left.y());
  }
 
  if (op2.top_right.y() > op1.top_right.y()) {
    op1.top_right.set_y(op2.top_right.y());
  }
 
  return op1;
}
 
/**********************************************************************
 * operator&=
 *
 * Reduce one box to intersection with the other  (In place intersection)
 **********************************************************************/
 
TBOX &operator&=(TBOX &op1, const TBOX &op2) {
  if (op1.overlap(op2)) {
    if (op2.bot_left.x() > op1.bot_left.x()) {
      op1.bot_left.set_x(op2.bot_left.x());
    }
 
    if (op2.top_right.x() < op1.top_right.x()) {
      op1.top_right.set_x(op2.top_right.x());
    }
 
    if (op2.bot_left.y() > op1.bot_left.y()) {
      op1.bot_left.set_y(op2.bot_left.y());
    }
 
    if (op2.top_right.y() < op1.top_right.y()) {
      op1.top_right.set_y(op2.top_right.y());
    }
  } else {
    op1.bot_left.set_x(INT16_MAX);
    op1.bot_left.set_y(INT16_MAX);
    op1.top_right.set_x(-INT16_MAX);
    op1.top_right.set_y(-INT16_MAX);
  }
  return op1;
}
 
bool TBOX::x_almost_equal(const TBOX &box, int tolerance) const {
  return (abs(left() - box.left()) <= tolerance && abs(right() - box.right()) <= tolerance);
}
 
bool TBOX::almost_equal(const TBOX &box, int tolerance) const {
  return (abs(left() - box.left()) <= tolerance && abs(right() - box.right()) <= tolerance &&
          abs(top() - box.top()) <= tolerance && abs(bottom() - box.bottom()) <= tolerance);
}
 
} // namespace tesseract