Code

Prevent localized doubles from being written into filter matrices
[inkscape.git] / src / 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  *   Abhishek Sharma
8 *
9 * Copyright (C) 2005 Authors
10 *
11 * Released under GNU LGPL.  Read the file 'COPYING' for more information.
12 */
13 #include "util/glib-list-iterators.h"
14 #include "sp-item.h"
15 #include "sp-item-transform.h"
16 #include "libvpsc/generate-constraints.h"
17 #include "libvpsc/remove_rectangle_overlap.h"
18 #include <utility>
20 using vpsc::Rectangle;
22 namespace {
23         struct Record {
24                 SPItem *item;
25                 Geom::Point midpoint;
26                 Rectangle *vspc_rect;
28                 Record() {}
29                 Record(SPItem *i, Geom::Point m, Rectangle *r)
30                 : item(i), midpoint(m), vspc_rect(r) {}
31         };
32 }
34 /**
35 * Takes a list of inkscape items and moves them as little as possible
36 * such that rectangular bounding boxes are separated by at least xGap
37 * horizontally and yGap vertically
38 */
39 void removeoverlap(GSList const *const items, double const xGap, double const yGap) {
40         using Inkscape::Util::GSListConstIterator;
41         std::list<SPItem *> selected;
42         selected.insert<GSListConstIterator<SPItem *> >(selected.end(), items, NULL);
43         std::vector<Record> records;
44         std::vector<Rectangle *> rs;
46         Geom::Point const gap(xGap, yGap);
47         for (std::list<SPItem *>::iterator it(selected.begin());
48                 it != selected.end();
49                 ++it)
50         {
51                 using Geom::X; using Geom::Y;
52                 Geom::OptRect item_box((*it)->getBboxDesktop());
53                 if (item_box) {
54                         Geom::Point min(item_box->min() - .5*gap);
55                         Geom::Point max(item_box->max() + .5*gap);
56                         // A negative gap is allowed, but will lead to problems when the gap is larger than
57                         // the bounding box (in either X or Y direction, or both); min will have become max
58                         // now, which cannot be handled by Rectangle() which is called below. And how will
59                         // removeRectangleOverlap handle such a case?
60                         // That's why we will enforce some boundaries on min and max here:
61                         if (max[X] < min[X]) {
62                                 min[X] = max[X] = (min[X] + max[X])/2;
63                         }
64                         if (max[Y] < min[Y]) {
65                                 min[Y] = max[Y] = (min[Y] + max[Y])/2;
66                         }
67                         Rectangle *vspc_rect = new Rectangle(min[X], max[X], min[Y], max[Y]);
68                         records.push_back(Record(*it, item_box->midpoint(), vspc_rect));
69                         rs.push_back(vspc_rect);
70                 }
71         }
72         if (!rs.empty()) {
73                 removeRectangleOverlap(rs.size(), &rs[0], 0.0, 0.0);
74         }
75         for ( std::vector<Record>::iterator it = records.begin();
76               it != records.end();
77               ++it )
78         {
79                 Geom::Point const curr = it->midpoint;
80                 Geom::Point const dest(it->vspc_rect->getCentreX(),
81                                      it->vspc_rect->getCentreY());
82                 sp_item_move_rel(it->item, Geom::Translate(dest - curr));
83                 delete it->vspc_rect;
84         }
85 }