Implementing feature request #1673807: snapping of gradient handles

(bzr r2722)

4 files changed, 29 insertions, 16 deletions

diff --git a/src/arc-context.cpp b/src/arc-context.cpp
index 1071d6f5d..db64d7951 100644
--- a/src/arc-context.cpp
+++ b/src/arc-context.cpp
@@ -274,7 +274,7 @@ static gint sp_arc_context_root_handler(SPEventContext *event_context, GdkEvent
             }
             break;
         case GDK_MOTION_NOTIFY:
-            if (dragging && event->motion.state && GDK_BUTTON1_MASK) {
+            if (dragging && (event->motion.state & GDK_BUTTON1_MASK)) {
 
                 if ( event_context->within_tolerance
                      && ( abs( (gint) event->motion.x - event_context->xp ) < event_context->tolerance )
diff --git a/src/gradient-context.cpp b/src/gradient-context.cpp
index c44cf1c59..42b4df578 100644
--- a/src/gradient-context.cpp
+++ b/src/gradient-context.cpp
@@ -44,7 +44,8 @@
 #include "sp-stop.h"
 #include "svg/css-ostringstream.h"
 #include "svg/svg-color.h"
-
+#include "snap.h"
+#include "sp-namedview.h"
 
 
 
@@ -410,8 +411,9 @@ sp_gradient_context_root_handler(SPEventContext *event_context, GdkEvent *event)
             /* Position center */
             NR::Point const button_dt = desktop->w2d(button_w);
             /* Snap center to nearest magnetic point */
-
-            rc->origin = button_dt;
+            
+            SnapManager const &m = desktop->namedview->snap_manager;
+            rc->origin = m.freeSnap(Inkscape::Snapper::BBOX_POINT | Inkscape::Snapper::SNAP_POINT, button_dt, NULL).getPoint();
 
             ret = TRUE;
         }
diff --git a/src/gradient-drag.cpp b/src/gradient-drag.cpp
index 4a8f7e8ed..d671b4823 100644
--- a/src/gradient-drag.cpp
+++ b/src/gradient-drag.cpp
@@ -41,6 +41,10 @@
 #include "gradient-drag.h"
 #include "sp-stop.h"
 
+#include "snap.h"
+#include "sp-namedview.h"
+
+
 #define GR_KNOT_COLOR_NORMAL 0xffffff00
 #define GR_KNOT_COLOR_SELECTED 0x0000ff00
 
@@ -429,19 +433,26 @@ gr_knot_moved_handler(SPKnot *knot, NR::Point const *ppointer, guint state, gpoi
         }
     }
 
-
     if (!((state & GDK_SHIFT_MASK) || ((state & GDK_CONTROL_MASK) && (state & GDK_MOD1_MASK)))) {
-        // See if we need to snap to any of the levels
-        for (guint i = 0; i < dragger->parent->hor_levels.size(); i++) {
-            if (fabs(p[NR::Y] - dragger->parent->hor_levels[i]) < snap_dist) {
-                p[NR::Y] = dragger->parent->hor_levels[i];
-                sp_knot_moveto (knot, &p);
+        // Try snapping to the grid or guides
+        SnapManager const &m = dragger->parent->desktop->namedview->snap_manager;
+        Inkscape::SnappedPoint s = m.freeSnap(Inkscape::Snapper::SNAP_POINT | Inkscape::Snapper::BBOX_POINT, p, NULL);
+        if (s.getDistance() < 1e6) {
+            p = s.getPoint();
+            sp_knot_moveto (knot, &p);
+        } else {
+            // No snapping so far, let's see if we need to snap to any of the levels
+            for (guint i = 0; i < dragger->parent->hor_levels.size(); i++) {
+                if (fabs(p[NR::Y] - dragger->parent->hor_levels[i]) < snap_dist) {
+                    p[NR::Y] = dragger->parent->hor_levels[i];
+                    sp_knot_moveto (knot, &p);
+                }
             }
-        }
-        for (guint i = 0; i < dragger->parent->vert_levels.size(); i++) {
-            if (fabs(p[NR::X] - dragger->parent->vert_levels[i]) < snap_dist) {
-                p[NR::X] = dragger->parent->vert_levels[i];
-                sp_knot_moveto (knot, &p);
+            for (guint i = 0; i < dragger->parent->vert_levels.size(); i++) {
+                if (fabs(p[NR::X] - dragger->parent->vert_levels[i]) < snap_dist) {
+                    p[NR::X] = dragger->parent->vert_levels[i];
+                    sp_knot_moveto (knot, &p);
+                }
             }
         }
     }
diff --git a/src/spiral-context.cpp b/src/spiral-context.cpp
index ef3e3470b..f912d6614 100644
--- a/src/spiral-context.cpp
+++ b/src/spiral-context.cpp
@@ -276,7 +276,7 @@ sp_spiral_context_root_handler(SPEventContext *event_context, GdkEvent *event)
             }
             break;
         case GDK_MOTION_NOTIFY:
-            if (dragging && event->motion.state && GDK_BUTTON1_MASK) {
+            if (dragging && (event->motion.state & GDK_BUTTON1_MASK)) {
 
                 if ( event_context->within_tolerance
                      && ( abs( (gint) event->motion.x - event_context->xp ) < event_context->tolerance )