src/removeoverlap/removeoverlap.cpp

   1 /** \file
   2  * Interface between Inkscape code (SPItem) and remove-overlaps function.
   3  */
   4 /*
   5 * Authors:
   6 *   Tim Dwyer <tgdwyer@gmail.com>
   7 *
   8 * Copyright (C) 2005 Authors
   9 *
  10 * Released under GNU LGPL.  Read the file 'COPYING' for more information.
  11 */
  12 #include "util/glib-list-iterators.h"
  13 #include "sp-item.h"
  14 #include "sp-item-transform.h"
  15 #include "libvpsc/generate-constraints.h"
  16 #include "libvpsc/remove_rectangle_overlap.h"
  17
  18 using vpsc::Rectangle;
  19
  20 /**
  21 * Takes a list of inkscape items and moves them as little as possible
  22 * such that rectangular bounding boxes are separated by at least xGap
  23 * horizontally and yGap vertically
  24 */
  25 void removeoverlap(GSList const *const items, double const xGap, double const yGap) {
  26         if(!items) {
  27                 return;
  28         }
  29
  30         using Inkscape::Util::GSListConstIterator;
  31         std::list<SPItem *> selected;
  32         selected.insert<GSListConstIterator<SPItem *> >(selected.end(), items, NULL);
  33         if (selected.empty()) return;
  34         int n=selected.size();
  35
  36         //Check 2 or more selected objects
  37         if (n < 2) return;
  38
  39         Rectangle **rs = new Rectangle*[n];
  40         int i=0;
  41
  42         NR::Point const gap(xGap, yGap);
  43         for (std::list<SPItem *>::iterator it(selected.begin());
  44                 it != selected.end();
  45                 ++it)
  46         {
  47                 using NR::X; using NR::Y;
  48                 NR::Rect const item_box(sp_item_bbox_desktop(*it));
  49
  50                 /* The current algorithm requires widths & heights to be strictly positive. */
  51                 NR::Point min(item_box.min());
  52                 NR::Point max(item_box.max());
  53                 for (unsigned d = 0; d < 2; ++d) {
  54                         double const minsize = 1; // arbitrary positive number
  55                         if (max[d] - min[d] + gap[d] < minsize) {
  56                                 double const mid = .5 * (min[d] + max[d]);
  57                                 min[d] = mid - .5*minsize;
  58                                 max[d] = mid + .5*minsize;
  59                         } else {
  60                                 min[d] -= .5*gap[d];
  61                                 max[d] += .5*gap[d];
  62                         }
  63                 }
  64                 rs[i++] = new Rectangle(min[X], max[X],
  65                                         min[Y], max[Y]);
  66         }
  67         removeRectangleOverlap(n, rs, 0.0, 0.0);
  68         i=0;
  69         for (std::list<SPItem *>::iterator it(selected.begin());
  70                 it != selected.end();
  71                 ++it)
  72         {
  73                 NR::Rect const item_box(sp_item_bbox_desktop(*it));
  74                 Rectangle *r = rs[i++];
  75                 NR::Point const curr(item_box.midpoint());
  76                 NR::Point const dest(r->getCentreX(),
  77                                      r->getCentreY());
  78                 sp_item_move_rel(*it, NR::translate(dest - curr));
  79                 delete r;
  80         }
  81         delete [] rs;
  82 }