Refactoring the snapping API (making it easier to maintain and understand for the devs)

(bzr r8960)

1 files changed, 147 insertions, 0 deletions

diff --git a/src/snap-candidate.h b/src/snap-candidate.h
new file mode 100644
index 000000000..39386c1ee
--- /dev/null
+++ b/src/snap-candidate.h
@@ -0,0 +1,147 @@
+#ifndef SEEN_SNAP_CANDIDATE_H
+#define SEEN_SNAP_CANDIDATE_H
+
+/**
+ * \file snap-candidate.h
+ * \brief some utility classes to store various kinds of snap candidates.
+ *
+ * Authors:
+ *   Diederik van Lierop <mail@diedenrezi.nl>
+ *
+ * Copyright (C) 2010 Authors
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+//#include "snapped-point.h"
+struct SPItem; // forward declaration
+
+namespace Inkscape {
+
+enum SnapTargetType {
+    SNAPTARGET_UNDEFINED = 0,
+    SNAPTARGET_GRID,
+    SNAPTARGET_GRID_INTERSECTION,
+    SNAPTARGET_GUIDE,
+    SNAPTARGET_GUIDE_INTERSECTION,
+    SNAPTARGET_GUIDE_ORIGIN,
+    SNAPTARGET_GRID_GUIDE_INTERSECTION,
+    SNAPTARGET_NODE_SMOOTH,
+    SNAPTARGET_NODE_CUSP,
+    SNAPTARGET_LINE_MIDPOINT,
+    SNAPTARGET_OBJECT_MIDPOINT,
+    SNAPTARGET_ROTATION_CENTER,
+    SNAPTARGET_HANDLE,
+    SNAPTARGET_PATH,
+    SNAPTARGET_PATH_INTERSECTION,
+    SNAPTARGET_BBOX_CORNER,
+    SNAPTARGET_BBOX_EDGE,
+    SNAPTARGET_BBOX_EDGE_MIDPOINT,
+    SNAPTARGET_BBOX_MIDPOINT,
+    SNAPTARGET_PAGE_BORDER,
+    SNAPTARGET_PAGE_CORNER,
+    SNAPTARGET_CONVEX_HULL_CORNER,
+    SNAPTARGET_ELLIPSE_QUADRANT_POINT,
+    SNAPTARGET_CENTER, // of ellipse
+    SNAPTARGET_CORNER, // of image or of rectangle
+    SNAPTARGET_TEXT_BASELINE,
+    SNAPTARGET_CONSTRAINED_ANGLE
+};
+
+enum SnapSourceType {
+    SNAPSOURCE_UNDEFINED = 0,
+    SNAPSOURCE_BBOX_CORNER,
+    SNAPSOURCE_BBOX_MIDPOINT,
+    SNAPSOURCE_BBOX_EDGE_MIDPOINT,
+    SNAPSOURCE_NODE_SMOOTH,
+    SNAPSOURCE_NODE_CUSP,
+    SNAPSOURCE_LINE_MIDPOINT,
+    SNAPSOURCE_OBJECT_MIDPOINT,
+    SNAPSOURCE_ROTATION_CENTER,
+    SNAPSOURCE_HANDLE,
+    SNAPSOURCE_PATH_INTERSECTION,
+    SNAPSOURCE_GUIDE,
+    SNAPSOURCE_GUIDE_ORIGIN,
+    SNAPSOURCE_CONVEX_HULL_CORNER,
+    SNAPSOURCE_ELLIPSE_QUADRANT_POINT,
+    SNAPSOURCE_CENTER, // of ellipse
+    SNAPSOURCE_CORNER, // of image or of rectangle
+    SNAPSOURCE_TEXT_BASELINE
+};
+
+/// Class to store data for points which are snap candidates, either as a source or as a target
+class SnapCandidatePoint
+{
+public:
+    SnapCandidatePoint(Geom::Point const &point, Inkscape::SnapSourceType const source, long const source_num, Inkscape::SnapTargetType const target, Geom::Rect const &bbox)
+        : _point(point), _source_type(source), _target_type(target), _source_num(source_num), _target_bbox(bbox) {};
+
+    SnapCandidatePoint(Geom::Point const &point, Inkscape::SnapSourceType const source, Inkscape::SnapTargetType const target)
+        : _point(point), _source_type(source), _target_type(target)
+    {
+        _source_num = 0;
+        _target_bbox = Geom::Rect();
+    }
+
+    SnapCandidatePoint(Geom::Point const &point, Inkscape::SnapSourceType const source, long const source_num = 0)
+        : _point(point), _source_type(source), _target_type(Inkscape::SNAPTARGET_UNDEFINED), _source_num(source_num) {_target_bbox = Geom::Rect();}
+
+    inline Geom::Point const & getPoint() const {return _point;}
+    inline Inkscape::SnapSourceType getSourceType() const {return _source_type;}
+    inline Inkscape::SnapTargetType getTargetType() const {return _target_type;}
+    inline long getSourceNum() const {return _source_num;}
+    inline Geom::Rect const & getTargetBBox() const {return _target_bbox;}
+
+private:
+    // Coordinates of the point
+    Geom::Point _point;
+
+    // If this SnapCandidatePoint is a snap source, then _source_type must be defined. If it
+    // is a snap target, then _target_type must be defined. If it's yet unknown whether it will
+    // be a source or target, then both may be defined
+    Inkscape::SnapSourceType _source_type;
+    Inkscape::SnapTargetType _target_type;
+
+    //Sequence number of the source point within the set of points that is to be snapped. Starting at zero
+    long _source_num;
+
+    // If this is a target and it belongs to a bounding box, e.g. when the target type is
+    // SNAPTARGET_BBOX_EDGE_MIDPOINT, then _target_bbox stores the relevant bounding box
+    Geom::Rect _target_bbox;
+};
+
+class SnapCandidateItem
+{
+public:
+    SnapCandidateItem(SPItem* item, bool clip_or_mask, Geom::Matrix _additional_affine)
+        : item(item), clip_or_mask(clip_or_mask), additional_affine(additional_affine) {}
+    ~SnapCandidateItem() {};
+
+    SPItem* item;        // An item that is to be considered for snapping to
+    bool clip_or_mask;    // If true, then item refers to a clipping path or a mask
+
+    /* To find out the absolute position of a clipping path or mask, we not only need to know
+     * the transformation of the clipping path or mask itself, but also the transformation of
+     * the object to which the clip or mask is being applied; that transformation is stored here
+     */
+    Geom::Matrix additional_affine;
+}
+;
+
+class SnapCandidatePath
+{
+
+public:
+    SnapCandidatePath(Geom::PathVector* path, SnapTargetType target, bool edited = false)
+        : path_vector(path), target_type(target), currently_being_edited(edited) {}
+    ~SnapCandidatePath() {};
+
+    Geom::PathVector* path_vector;
+    SnapTargetType target_type;
+    bool currently_being_edited; // true for the path that's currently being edited in the node tool (if any)
+
+};
+
+} // end of namespace Inkscape
+
+#endif /* !SEEN_SNAP_CANDIDATE_H */