src/object-snapper.h

   1 #ifndef SEEN_OBJECT_SNAPPER_H
   2 #define SEEN_OBJECT_SNAPPER_H
   3
   4 /**
   5  *  \file object-snapper.h
   6  *  \brief Snapping things to objects.
   7  *
   8  * Authors:
   9  *   Carl Hetherington <inkscape@carlh.net>
  10  *   Diederik van Lierop <mail@diedenrezi.nl>
  11  *
  12  * Copyright (C) 2005 - 2008 Authors
  13  *
  14  * Released under GNU GPL, read the file 'COPYING' for more information
  15  */
  16
  17 #include "snapper.h"
  18 #include "sp-path.h"
  19 #include "splivarot.h"
  20
  21 struct SPNamedView;
  22 struct SPItem;
  23 struct SPObject;
  24
  25 namespace Inkscape
  26 {
  27
  28 class SnapCandidate
  29
  30 {
  31 public:
  32     SnapCandidate(SPItem* item, bool clip_or_mask, Geom::Matrix _additional_affine);
  33     ~SnapCandidate();
  34
  35     SPItem* item;        // An item that is to be considered for snapping to
  36     bool clip_or_mask;    // If true, then item refers to a clipping path or a mask
  37
  38     /* To find out the absolute position of a clipping path or mask, we not only need to know
  39      * the transformation of the clipping path or mask itself, but also the transformation of
  40      * the object to which the clip or mask is being applied; that transformation is stored here
  41      */
  42     Geom::Matrix additional_affine;
  43 };
  44
  45 class ObjectSnapper : public Snapper
  46 {
  47
  48 public:
  49         ObjectSnapper(SnapManager *sm, Geom::Coord const d);
  50     ~ObjectSnapper();
  51
  52         enum DimensionToSnap {
  53                 GUIDE_TRANSL_SNAP_X, // For snapping a vertical guide (normal in the X-direction) to objects,
  54                 GUIDE_TRANSL_SNAP_Y, // For snapping a horizontal guide (normal in the Y-direction) to objects
  55                 ANGLED_GUIDE_TRANSL_SNAP, // For snapping an angled guide, while translating it accross the desktop
  56                 ANGLED_GUIDE_ROT_SNAP, // For snapping an angled guide, while rotating it around some pivot point
  57                 TRANSL_SNAP_XY}; // All other cases; for snapping to objects, other than guides
  58
  59         void guideSnap(SnappedConstraints &sc,
  60                                    Geom::Point const &p,
  61                                    Geom::Point const &guide_normal) const;
  62
  63         bool ThisSnapperMightSnap() const;
  64         bool GuidesMightSnap() const;
  65
  66         Geom::Coord getSnapperTolerance() const; //returns the tolerance of the snapper in screen pixels (i.e. independent of zoom)
  67         bool getSnapperAlwaysSnap() const; //if true, then the snapper will always snap, regardless of its tolerance
  68
  69         void freeSnap(SnappedConstraints &sc,
  70                                   Inkscape::SnapPreferences::PointType const &t,
  71                                   Geom::Point const &p,
  72                                   bool const &first_point,
  73                                   Geom::OptRect const &bbox_to_snap,
  74                                   std::vector<SPItem const *> const *it,
  75                                   std::vector<Geom::Point> *unselected_nodes) const;
  76
  77         void constrainedSnap(SnappedConstraints &sc,
  78                                   Inkscape::SnapPreferences::PointType const &t,
  79                                   Geom::Point const &p,
  80                                   bool const &first_point,
  81                                   Geom::OptRect const &bbox_to_snap,
  82                                   ConstraintLine const &c,
  83                                   std::vector<SPItem const *> const *it) const;
  84
  85 private:
  86     //store some lists of candidates, points and paths, so we don't have to rebuild them for each point we want to snap
  87     std::vector<SnapCandidate> *_candidates;
  88     std::vector<Geom::Point> *_points_to_snap_to;
  89     std::vector<Geom::PathVector*> *_paths_to_snap_to;
  90
  91     void _findCandidates(SPObject* parent,
  92                        std::vector<SPItem const *> const *it,
  93                        bool const &first_point,
  94                        Geom::Rect const &bbox_to_snap,
  95                        DimensionToSnap snap_dim,
  96                        bool const _clip_or_mask,
  97                        Geom::Matrix const additional_affine) const;
  98
  99     void _snapNodes(SnappedConstraints &sc,
 100                       Inkscape::SnapPreferences::PointType const &t,
 101                       Geom::Point const &p, // in desktop coordinates
 102                       bool const &first_point,
 103                       std::vector<Geom::Point> *unselected_nodes) const; // in desktop coordinates
 104
 105     void _snapTranslatingGuideToNodes(SnappedConstraints &sc,
 106                      Inkscape::SnapPreferences::PointType const &t,
 107                      Geom::Point const &p,
 108                      Geom::Point const &guide_normal) const;
 109
 110     void _collectNodes(Inkscape::SnapPreferences::PointType const &t,
 111                   bool const &first_point) const;
 112
 113     void _snapPaths(SnappedConstraints &sc,
 114                       Inkscape::SnapPreferences::PointType const &t,
 115                       Geom::Point const &p,     // in desktop coordinates
 116                       bool const &first_point,
 117                       std::vector<Geom::Point> *unselected_nodes, // in desktop coordinates
 118                       SPPath const *selected_path) const;
 119
 120     void _snapPathsConstrained(SnappedConstraints &sc,
 121                  Inkscape::SnapPreferences::PointType const &t,
 122                  Geom::Point const &p, // in desktop coordinates
 123                  bool const &first_point,
 124                  ConstraintLine const &c) const;
 125
 126     bool isUnselectedNode(Geom::Point const &point, std::vector<Geom::Point> const *unselected_nodes) const;
 127
 128     void _collectPaths(Inkscape::SnapPreferences::PointType const &t,
 129                   bool const &first_point) const;
 130
 131     void _clear_paths() const;
 132     Geom::PathVector* _getBorderPathv() const;
 133     Geom::PathVector* _getPathvFromRect(Geom::Rect const rect) const;
 134     void _getBorderNodes(std::vector<Geom::Point> *points) const;
 135
 136 }; // end of ObjectSnapper class
 137
 138 void getBBoxPoints(Geom::OptRect const bbox, std::vector<Geom::Point> *points, bool const includeCorners, bool const includeLineMidpoints, bool const includeObjectMidpoints);
 139
 140 } // end of namespace Inkscape
 141
 142 #endif