tigervnc/common/rfb/Region.cxx

/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
 * Copyright 2016-2020 Pierre Ossman for Cendio AB
 * 
 * This 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 software 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 software; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
 * USA.
 */

#include <rfb/Region.h>
#include <rfb/LogWriter.h>

extern "C" {
#include <pixman.h>
}

static rfb::LogWriter vlog("Region");

rfb::Region::Region() {
  rgn = new struct pixman_region16;
  pixman_region_init(rgn);
}

rfb::Region::Region(const Rect& r) {
  rgn = new struct pixman_region16;
  pixman_region_init_rect(rgn, r.tl.x, r.tl.y, r.width(), r.height());
}

rfb::Region::Region(const rfb::Region& r) {
  rgn = new struct pixman_region16;
  pixman_region_init(rgn);
  pixman_region_copy(rgn, r.rgn);
}

rfb::Region::~Region() {
  pixman_region_fini(rgn);
  delete rgn;
}

rfb::Region& rfb::Region::operator=(const rfb::Region& r) {
  pixman_region_copy(rgn, r.rgn);
  return *this;
}

void rfb::Region::clear() {
  // pixman_region_clear() isn't available on some older systems
  pixman_region_fini(rgn);
  pixman_region_init(rgn);
}

void rfb::Region::reset(const Rect& r) {
  pixman_region_fini(rgn);
  pixman_region_init_rect(rgn, r.tl.x, r.tl.y, r.width(), r.height());
}

void rfb::Region::translate(const Point& delta) {
  pixman_region_translate(rgn, delta.x, delta.y);
}

void rfb::Region::assign_intersect(const rfb::Region& r) {
  pixman_region_intersect(rgn, rgn, r.rgn);
}

void rfb::Region::assign_union(const rfb::Region& r) {
  pixman_region_union(rgn, rgn, r.rgn);
}

void rfb::Region::assign_subtract(const rfb::Region& r) {
  pixman_region_subtract(rgn, rgn, r.rgn);
}

rfb::Region rfb::Region::intersect(const rfb::Region& r) const {
  rfb::Region ret;
  pixman_region_intersect(ret.rgn, rgn, r.rgn);
  return ret;
}

rfb::Region rfb::Region::union_(const rfb::Region& r) const {
  rfb::Region ret;
  pixman_region_union(ret.rgn, rgn, r.rgn);
  return ret;
}

rfb::Region rfb::Region::subtract(const rfb::Region& r) const {
  rfb::Region ret;
  pixman_region_subtract(ret.rgn, rgn, r.rgn);
  return ret;
}

bool rfb::Region::equals(const rfb::Region& r) const {
  return pixman_region_equal(rgn, r.rgn);
}

int rfb::Region::numRects() const {
  return pixman_region_n_rects(rgn);
}

bool rfb::Region::get_rects(std::vector<Rect>* rects,
                            bool left2right, bool topdown) const
{
  int nRects;
  const pixman_box16_t* boxes;
  int xInc, yInc, i;

  boxes = pixman_region_rectangles(rgn, &nRects);

  rects->clear();
  rects->reserve(nRects);

  xInc = left2right ? 1 : -1;
  yInc = topdown ? 1 : -1;
  i = topdown ? 0 : nRects-1;

  while (nRects > 0) {
    int firstInNextBand = i;
    int nRectsInBand = 0;

    while (nRects > 0 && boxes[firstInNextBand].y1 == boxes[i].y1)
    {
      firstInNextBand += yInc;
      nRects--;
      nRectsInBand++;
    }

    if (xInc != yInc)
      i = firstInNextBand - yInc;

    while (nRectsInBand > 0) {
      Rect r(boxes[i].x1, boxes[i].y1, boxes[i].x2, boxes[i].y2);
      rects->push_back(r);
      i += xInc;
      nRectsInBand--;
    }

    i = firstInNextBand;
  }

  return !rects->empty();
}

rfb::Rect rfb::Region::get_bounding_rect() const {
  const pixman_box16_t* extents;
  extents = pixman_region_extents(rgn);
  return Rect(extents->x1, extents->y1, extents->x2, extents->y2);
}


void rfb::Region::debug_print(const char* prefix) const
{
  Rect extents;
  std::vector<Rect> rects;
  std::vector<Rect>::const_iterator iter;

  extents = get_bounding_rect();
  get_rects(&rects);

  vlog.debug("%s num rects %3ld extents %3d,%3d %3dx%3d",
          prefix, (long)rects.size(), extents.tl.x, extents.tl.y,
          extents.width(), extents.height());

  for (iter = rects.begin(); iter != rects.end(); ++iter) {
    vlog.debug("    rect %3d,%3d %3dx%3d",
               iter->tl.x, iter->tl.y, iter->width(), iter->height());
  }
}