Fix "snap guides" toggle

Fixed bugs:
  - https://launchpad.net/bugs/814457

(bzr r10582)

6 files changed, 70 insertions, 52 deletions

diff --git a/src/object-snapper.cpp b/src/object-snapper.cpp
index 82114e2c4..fd8ef0c7c 100644
--- a/src/object-snapper.cpp
+++ b/src/object-snapper.cpp
@@ -177,7 +177,7 @@ void Inkscape::ObjectSnapper::_collectNodes(SnapSourceType const &t,
 
         bool p_is_a_node = t & SNAPSOURCE_NODE_CATEGORY;
         bool p_is_a_bbox = t & SNAPSOURCE_BBOX_CATEGORY;
-        bool p_is_other = t & SNAPSOURCE_OTHERS_CATEGORY;
+        bool p_is_other = t & SNAPSOURCE_OTHERS_CATEGORY || t & SNAPSOURCE_DATUMS_CATEGORY;
 
         // A point considered for snapping should be either a node, a bbox corner or a guide/other. Pick only ONE!
         if (((p_is_a_node && p_is_a_bbox) || (p_is_a_bbox && p_is_other) || (p_is_a_node && p_is_other))) {
@@ -364,7 +364,7 @@ void Inkscape::ObjectSnapper::_collectPaths(Geom::Point /*p*/,
 
         bool p_is_a_node = source_type & SNAPSOURCE_NODE_CATEGORY;
         bool p_is_a_bbox = source_type & SNAPSOURCE_BBOX_CATEGORY;
-        bool p_is_other = source_type & SNAPSOURCE_OTHERS_CATEGORY;
+        bool p_is_other = source_type & SNAPSOURCE_OTHERS_CATEGORY || source_type & SNAPSOURCE_DATUMS_CATEGORY;
 
         if (_snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_BBOX_EDGE)) {
             Preferences *prefs = Preferences::get();
@@ -444,7 +444,7 @@ void Inkscape::ObjectSnapper::_collectPaths(Geom::Point /*p*/,
             }
 
             //Add the item's bounding box to snap to
-            if (_snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_BBOX_EDGE) && (_snapmanager->snapprefs.getSnapModeBBox() || _snapmanager->snapprefs.getSnapModeOthers())) {
+            if (_snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_BBOX_EDGE)) {
                 if (p_is_other || p_is_a_bbox || (!_snapmanager->snapprefs.getStrictSnapping() && p_is_a_node)) {
                     // Discard the bbox of a clipped path / mask, because we don't want to snap to both the bbox
                     // of the item AND the bbox of the clipping path at the same time
@@ -747,10 +747,7 @@ void Inkscape::ObjectSnapper::constrainedSnap( SnappedConstraints &sc,
  */
 bool Inkscape::ObjectSnapper::ThisSnapperMightSnap() const
 {
-    return _snapmanager->snapprefs.getSnapModeBBox()
-            || _snapmanager->snapprefs.getSnapModeNode()
-            || _snapmanager->snapprefs.getSnapModeOthers()
-            || _snapmanager->snapprefs.isTargetSnappable(SNAPTARGET_PAGE_CORNER);
+    return true;
 }
 
 void Inkscape::ObjectSnapper::_clear_paths() const
@@ -814,16 +811,13 @@ void Inkscape::getBBoxPoints(Geom::OptRect const bbox,
 
 bool Inkscape::ObjectSnapper::_allowSourceToSnapToTarget(SnapSourceType source, SnapTargetType target, bool strict_snapping) const
 {
-    bool allow_this_pair_to_snap = false;
+    bool allow_this_pair_to_snap = true;
 
     if (strict_snapping) { // bounding boxes will not snap to nodes/paths and vice versa
-        int source_cat = source & (SNAPSOURCE_BBOX_CATEGORY | SNAPSOURCE_NODE_CATEGORY | SNAPSOURCE_OTHERS_CATEGORY);
-        int target_cat = target & (SNAPTARGET_BBOX_CATEGORY | SNAPTARGET_NODE_CATEGORY | SNAPTARGET_OTHERS_CATEGORY);
-        if (source_cat == target_cat || source_cat == SNAPSOURCE_OTHERS_CATEGORY || target_cat == SNAPTARGET_OTHERS_CATEGORY) {
-            allow_this_pair_to_snap = true;
+        if (((source & SNAPSOURCE_BBOX_CATEGORY) && (target & SNAPTARGET_NODE_CATEGORY)) ||
+            ((source & SNAPSOURCE_NODE_CATEGORY) && (target & SNAPTARGET_BBOX_CATEGORY))) {
+            allow_this_pair_to_snap = false;
         }
-    } else { // anything will snap to anything
-        allow_this_pair_to_snap = true;
     }
 
     return allow_this_pair_to_snap;
diff --git a/src/seltrans.cpp b/src/seltrans.cpp
index 7538e15d9..3a204a49e 100644
--- a/src/seltrans.cpp
+++ b/src/seltrans.cpp
@@ -360,7 +360,7 @@ void Inkscape::SelTrans::grab(Geom::Point const &p, gdouble x, gdouble y, bool s
     // points immediately.
 
     if (prefs->getBool("/options/snapclosestonly/value", false)) {
-        if (m.snapprefs.getSnapModeNode() || m.snapprefs.getSnapModeOthers()) {
+        if (m.snapprefs.getSnapModeNode() || m.snapprefs.getSnapModeOthers() || m.snapprefs.getSnapModeDatums()) {
             m.keepClosestPointOnly(_snap_points, p);
         } else {
             _snap_points.clear(); // don't keep any point
diff --git a/src/snap-enums.h b/src/snap-enums.h
index fd28910a8..8a95bb2dd 100644
--- a/src/snap-enums.h
+++ b/src/snap-enums.h
@@ -20,14 +20,14 @@ enum SnapSourceType {
     //-------------------------------------------------------------------
     // Bbox points can be located at the edge of the stroke (for visual bboxes); they will therefore not snap
     // to nodes because these are always located at the center of the stroke
-    SNAPSOURCE_BBOX_CATEGORY = 32, // will be used as a flag and must therefore be a power of two. Also,
+    SNAPSOURCE_BBOX_CATEGORY = 16, // will be used as a flag and must therefore be a power of two. Also,
                                    // must be larger than the largest number of targets in a single group
     SNAPSOURCE_BBOX_CORNER,
     SNAPSOURCE_BBOX_MIDPOINT,
     SNAPSOURCE_BBOX_EDGE_MIDPOINT,
     //-------------------------------------------------------------------
     // For the same reason, nodes will not snap to bbox points
-    SNAPSOURCE_NODE_CATEGORY = 64, // will be used as a flag and must therefore be a power of two
+    SNAPSOURCE_NODE_CATEGORY = 32, // will be used as a flag and must therefore be a power of two
     SNAPSOURCE_NODE_SMOOTH, // Symmetrical nodes are also considered to be smooth; there's no dedicated type for symm. nodes
     SNAPSOURCE_NODE_CUSP,
     SNAPSOURCE_LINE_MIDPOINT,
@@ -37,13 +37,16 @@ enum SnapSourceType {
     SNAPSOURCE_ELLIPSE_QUADRANT_POINT,
     SNAPSOURCE_NODE_HANDLE, // eg. nodes in the path editor, handles of stars or rectangles, etc. (tied to a stroke)
     //-------------------------------------------------------------------
-    // Other points (e.g. guides, gradient knots) will snap to both bounding boxes and nodes
+    // Other points (e.g. guides) will snap to both bounding boxes and nodes
+    SNAPSOURCE_DATUMS_CATEGORY = 64, // will be used as a flag and must therefore be a power of two
+    SNAPSOURCE_GUIDE,
+    SNAPSOURCE_GUIDE_ORIGIN,
+    //-------------------------------------------------------------------
+    // Other points (e.g. gradient knots, image corners) will snap to both bounding boxes and nodes
     SNAPSOURCE_OTHERS_CATEGORY = 128, // will be used as a flag and must therefore be a power of two
     SNAPSOURCE_ROTATION_CENTER,
     SNAPSOURCE_OBJECT_MIDPOINT, // midpoint of rectangles, ellipses, polygon, etc.
     SNAPSOURCE_IMG_CORNER,
-    SNAPSOURCE_GUIDE,
-    SNAPSOURCE_GUIDE_ORIGIN,
     SNAPSOURCE_TEXT_ANCHOR,
     SNAPSOURCE_OTHER_HANDLE, // eg. the handle of a gradient or of a connector (ie not being tied to a stroke)
     SNAPSOURCE_GRID_PITCH, // eg. when pasting or alt-dragging in the selector tool; not realy a snap source
@@ -52,7 +55,7 @@ enum SnapSourceType {
 enum SnapTargetType {
     SNAPTARGET_UNDEFINED = 0,
     //-------------------------------------------------------------------
-    SNAPTARGET_BBOX_CATEGORY = 32, // will be used as a flag and must therefore be a power of two. Also,
+    SNAPTARGET_BBOX_CATEGORY = 16, // will be used as a flag and must therefore be a power of two. Also,
                                    // must be larger than the largest number of targets in a single group
                                    // i.e > 15 because that's the number of targets in the "others" group
     SNAPTARGET_BBOX_CORNER,
@@ -60,7 +63,7 @@ enum SnapTargetType {
     SNAPTARGET_BBOX_EDGE_MIDPOINT,
     SNAPTARGET_BBOX_MIDPOINT,
     //-------------------------------------------------------------------
-    SNAPTARGET_NODE_CATEGORY = 64, // will be used as a flag and must therefore be a power of two
+    SNAPTARGET_NODE_CATEGORY = 32, // will be used as a flag and must therefore be a power of two
     SNAPTARGET_NODE_SMOOTH,
     SNAPTARGET_NODE_CUSP,
     SNAPTARGET_LINE_MIDPOINT,
@@ -69,18 +72,20 @@ enum SnapTargetType {
     SNAPTARGET_ELLIPSE_QUADRANT_POINT, // this corner is at the center of the stroke
     SNAPTARGET_RECT_CORNER, // of a rectangle, so this corner is at the center of the stroke
     //-------------------------------------------------------------------
-    SNAPTARGET_OTHERS_CATEGORY = 128, // will be used as a flag and must therefore be a power of two
+    SNAPTARGET_DATUMS_CATEGORY = 64, // will be used as a flag and must therefore be a power of two
     SNAPTARGET_GRID,
     SNAPTARGET_GRID_INTERSECTION,
     SNAPTARGET_GUIDE,
     SNAPTARGET_GUIDE_INTERSECTION,
     SNAPTARGET_GUIDE_ORIGIN,
     SNAPTARGET_GRID_GUIDE_INTERSECTION,
+    SNAPTARGET_PAGE_BORDER,
+    SNAPTARGET_PAGE_CORNER,
+    //-------------------------------------------------------------------
+    SNAPTARGET_OTHERS_CATEGORY = 128, // will be used as a flag and must therefore be a power of two
     SNAPTARGET_OBJECT_MIDPOINT,
     SNAPTARGET_IMG_CORNER,
     SNAPTARGET_ROTATION_CENTER,
-    SNAPTARGET_PAGE_BORDER,
-    SNAPTARGET_PAGE_CORNER,
     SNAPTARGET_TEXT_ANCHOR,
     SNAPTARGET_TEXT_BASELINE,
     SNAPTARGET_CONSTRAINED_ANGLE,
diff --git a/src/snap-preferences.cpp b/src/snap-preferences.cpp
index b1fadcfff..d655564f2 100644
--- a/src/snap-preferences.cpp
+++ b/src/snap-preferences.cpp
@@ -19,14 +19,13 @@ Inkscape::SnapPreferences::SnapPreferences() :
     _snap_postponed_globally(false),
     _strict_snapping(true)
 {
-    // Check for enough space to hold all snap target toggles in the "others" group; see the comments in snap-enums.h
-    g_assert(SNAPTARGET_MAX_ENUM_VALUE - SNAPTARGET_OTHERS_CATEGORY < SNAPTARGET_BBOX_CATEGORY);
     // Check for powers of two; see the comments in snap-enums.h
     g_assert((SNAPTARGET_BBOX_CATEGORY != 0) && !(SNAPTARGET_BBOX_CATEGORY & (SNAPTARGET_BBOX_CATEGORY - 1)));
     g_assert((SNAPTARGET_NODE_CATEGORY != 0) && !(SNAPTARGET_NODE_CATEGORY & (SNAPTARGET_NODE_CATEGORY - 1)));
+    g_assert((SNAPTARGET_DATUMS_CATEGORY != 0) && !(SNAPTARGET_DATUMS_CATEGORY & (SNAPTARGET_DATUMS_CATEGORY - 1)));
     g_assert((SNAPTARGET_OTHERS_CATEGORY != 0) && !(SNAPTARGET_OTHERS_CATEGORY & (SNAPTARGET_OTHERS_CATEGORY - 1)));
 
-    setSnapFrom(SnapSourceType(SNAPSOURCE_BBOX_CATEGORY | SNAPSOURCE_NODE_CATEGORY | SNAPSOURCE_OTHERS_CATEGORY), true); //Snap any point. In v0.45 and earlier, this was controlled in the preferences tab
+    setSnapFrom(SnapSourceType(SNAPSOURCE_BBOX_CATEGORY | SNAPSOURCE_NODE_CATEGORY | SNAPSOURCE_DATUMS_CATEGORY | SNAPSOURCE_OTHERS_CATEGORY), true); //Snap any point. In v0.45 and earlier, this was controlled in the preferences tab
     for (int n = 0; n < Inkscape::SNAPTARGET_MAX_ENUM_VALUE; n++) {
         _active_snap_targets[n] = -1;
     }
@@ -88,6 +87,11 @@ bool Inkscape::SnapPreferences::getSnapModeOthers() const
     return (_snap_from & Inkscape::SNAPSOURCE_OTHERS_CATEGORY);
 }
 
+bool Inkscape::SnapPreferences::getSnapModeDatums() const
+{
+    return isTargetSnappable(Inkscape::SNAPTARGET_GUIDE);
+}
+
 bool Inkscape::SnapPreferences::getSnapModeAny() const
 {
     return (_snap_from != 0);
@@ -135,31 +139,55 @@ void Inkscape::SnapPreferences::_mapTargetToArrayIndex(Inkscape::SnapTargetType
 {
     if (target & SNAPTARGET_BBOX_CATEGORY) {
         group_on = getSnapModeBBox(); // Only if the group with bbox sources/targets has been enabled, then we might snap to any of the bbox targets
+
+
     } else if (target & SNAPTARGET_NODE_CATEGORY) {
         group_on = getSnapModeNode(); // Only if the group with path/node sources/targets has been enabled, then we might snap to any of the nodes/paths
         if (target == SNAPTARGET_RECT_CORNER || target == SNAPTARGET_ELLIPSE_QUADRANT_POINT) { // Don't have their own button; on when the group is on
             target = SNAPTARGET_NODE_CATEGORY;
         }
-    } else if (target & SNAPTARGET_OTHERS_CATEGORY) {
-        // Only if the group with "other" snap sources/targets has been enabled, then we might snap to any of those targets
-        // ... but this doesn't hold for the page border, grids, and guides
-        group_on = getSnapModeOthers();
+
+
+    } else if (target & SNAPTARGET_DATUMS_CATEGORY) {
+        group_on = true; // These snap targets cannot be disabled as part of a disabled group;
         switch (target) {
             // Some snap targets don't have their own toggle. These targets are called "secondary targets". We will re-map
-            // them to their cousin which does have a toggle, and which is called a "primary target"
+            // them to their cousin which does have a toggle, and which is called a "primary target"case SNAPTARGET_GRID_INTERSECTION:
             case SNAPTARGET_GRID_INTERSECTION:
-                group_on = true; // cannot be disabled as part of a disabled group;
                 target = SNAPTARGET_GRID;
                 break;
             case SNAPTARGET_GUIDE_INTERSECTION:
             case SNAPTARGET_GUIDE_ORIGIN:
-                group_on = true; // cannot be disabled as part of a disabled group;
                 target = SNAPTARGET_GUIDE;
                 break;
             case SNAPTARGET_PAGE_CORNER:
-                group_on = true; // cannot be disabled as part of a disabled group;
                 target = SNAPTARGET_PAGE_BORDER;
                 break;
+
+            // Some snap targets cannot be toggled at all, and are therefore always enabled
+            case SNAPTARGET_GRID_GUIDE_INTERSECTION:
+                always_on = true; // Doesn't have it's own button
+                break;
+
+            // These are only listed for completeness
+            case SNAPTARGET_GRID:
+            case SNAPTARGET_GUIDE:
+            case SNAPTARGET_PAGE_BORDER:
+            case SNAPTARGET_DATUMS_CATEGORY:
+                break;
+            default:
+                g_warning("Snap-preferences warning: Undefined snap target (#%i)", target);
+                break;
+        }
+
+
+    } else if (target & SNAPTARGET_OTHERS_CATEGORY) {
+        // Only if the group with "other" snap sources/targets has been enabled, then we might snap to any of those targets
+        // ... but this doesn't hold for the page border, grids, and guides
+        group_on = getSnapModeOthers();
+        switch (target) {
+            // Some snap targets don't have their own toggle. These targets are called "secondary targets". We will re-map
+            // them to their cousin which does have a toggle, and which is called a "primary target"
             case SNAPTARGET_TEXT_ANCHOR:
                 target = SNAPTARGET_TEXT_BASELINE;
                 break;
@@ -168,31 +196,23 @@ void Inkscape::SnapPreferences::_mapTargetToArrayIndex(Inkscape::SnapTargetType
                 target = SNAPTARGET_OTHERS_CATEGORY;
                 break;
             // Some snap targets cannot be toggled at all, and are therefore always enabled
-            case SNAPTARGET_GRID_GUIDE_INTERSECTION:
             case SNAPTARGET_CONSTRAINED_ANGLE:
             case SNAPTARGET_CONSTRAINT:
                 always_on = true; // Doesn't have it's own button
                 break;
-            case SNAPTARGET_GRID:
-            case SNAPTARGET_GUIDE:
-            case SNAPTARGET_PAGE_BORDER:
-                group_on = true; // cannot be disabled as part of a disabled group;
-                break;
 
             // These are only listed for completeness
             case SNAPTARGET_OBJECT_MIDPOINT:
             case SNAPTARGET_ROTATION_CENTER:
             case SNAPTARGET_TEXT_BASELINE:
-                break;
-
-            case SNAPTARGET_BBOX_CATEGORY:
-            case SNAPTARGET_NODE_CATEGORY:
             case SNAPTARGET_OTHERS_CATEGORY:
                 break;
             default:
                 g_warning("Snap-preferences warning: Undefined snap target (#%i)", target);
                 break;
         }
+
+
     } else if (target == SNAPTARGET_UNDEFINED ) {
         g_warning("Snap-preferences warning: Undefined snaptarget (#%i)", target);
     }
diff --git a/src/snap-preferences.h b/src/snap-preferences.h
index dac11b3aa..cfcdf6137 100644
--- a/src/snap-preferences.h
+++ b/src/snap-preferences.h
@@ -28,9 +28,6 @@ public:
     bool isTargetSnappable(Inkscape::SnapTargetType const target1, Inkscape::SnapTargetType const target2) const;
     bool isTargetSnappable(Inkscape::SnapTargetType const target1, Inkscape::SnapTargetType const target2, Inkscape::SnapTargetType const target3) const;
     bool isTargetSnappable(Inkscape::SnapTargetType const target1, Inkscape::SnapTargetType const target2, Inkscape::SnapTargetType const target3, Inkscape::SnapTargetType const target4) const;
-    //bool isAnyBBoxSnappable() const;
-    //bool isAnyNodeOrPathSnappable() const;
-    //bool isAnyOtherSnappable() const;
     bool isSnapButtonEnabled(Inkscape::SnapTargetType const target) const;
 
     void setSnapModeBBox(bool enabled);
@@ -38,6 +35,7 @@ public:
     void setSnapModeOthers(bool enabled);
     bool getSnapModeBBox() const;
     bool getSnapModeNode() const;
+    bool getSnapModeDatums() const;
     bool getSnapModeOthers() const;
     bool getSnapModeAny() const;
 
diff --git a/src/snap.cpp b/src/snap.cpp
index c4ca32364..7647341fe 100644
--- a/src/snap.cpp
+++ b/src/snap.cpp
@@ -1413,9 +1413,10 @@ void SnapManager::_displaySnapsource(Inkscape::SnapCandidatePoint const &p) cons
 
     Inkscape::Preferences *prefs = Inkscape::Preferences::get();
     if (prefs->getBool("/options/snapclosestonly/value")) {
-        bool p_is_a_node = p.getSourceType() & Inkscape::SNAPSOURCE_NODE_CATEGORY;
-        bool p_is_a_bbox = p.getSourceType() & Inkscape::SNAPSOURCE_BBOX_CATEGORY;
-        bool p_is_other = p.getSourceType() & Inkscape::SNAPSOURCE_OTHERS_CATEGORY;
+        Inkscape::SnapSourceType t = p.getSourceType();
+        bool p_is_a_node = t & Inkscape::SNAPSOURCE_NODE_CATEGORY;
+        bool p_is_a_bbox = t & Inkscape::SNAPSOURCE_BBOX_CATEGORY;
+        bool p_is_other = t & Inkscape::SNAPSOURCE_OTHERS_CATEGORY || t & Inkscape::SNAPSOURCE_DATUMS_CATEGORY;
 
         g_assert(_desktop != NULL);
         if (snapprefs.getSnapEnabledGlobally() && (p_is_other || (p_is_a_node && snapprefs.getSnapModeNode()) || (p_is_a_bbox && snapprefs.getSnapModeBBox()))) {