This commit fixes bug #1657874

Title Missing handles after reset of rotation center
Whats the bug: In a previous commit I do, I change a event on knots from onmove to onmousedown. this seems ok but the problem were if the user click on rotation center without moving it, the onrelease event has a variable move not set and hide the current knots making the needs to switch the tools to reshow. Is in particular a big problem on little elements where the center knot have a big influence and is very easy to click on it on select.
Why do this commit that broke: I want have onmousedown fired to allow meshgradient triangle knots updated on mouse down.
What fixes: INstras change the place of the signal, I send back to the original position and create a new signal to fire onmousedow a knot. In the gradient code I change the previous calls from undrag to onmousedown.

Fixed bugs:
  - https://launchpad.net/bugs/1657874

(bzr r15486)

4 files changed, 7 insertions, 6 deletions

diff --git a/src/gradient-drag.cpp b/src/gradient-drag.cpp
index a928cac0d..006e2f790 100644
--- a/src/gradient-drag.cpp
+++ b/src/gradient-drag.cpp
@@ -1067,7 +1067,7 @@ static void gr_knot_moved_midpoint_handler(SPKnot */*knot*/, Geom::Point const &
 
 
 
-static void gr_knot_grabbed_handler(SPKnot */*knot*/, unsigned int /*state*/, gpointer data)
+static void gr_knot_mousedown_handler(SPKnot */*knot*/, unsigned int /*state*/, gpointer data)
 {
     GrDragger *dragger = (GrDragger *) data;
     GrDrag *drag = dragger->parent;
@@ -1688,7 +1688,7 @@ GrDragger::GrDragger(GrDrag *parent, Geom::Point p, GrDraggable *draggable)
     this->sizeUpdatedConn = ControlManager::getManager().connectCtrlSizeChanged(sigc::mem_fun(*this, &GrDragger::updateControlSizes));
     this->_clicked_connection = this->knot->click_signal.connect(sigc::bind(sigc::ptr_fun(gr_knot_clicked_handler), this));
     this->_doubleclicked_connection = this->knot->doubleclicked_signal.connect(sigc::bind(sigc::ptr_fun(gr_knot_doubleclicked_handler), this));
-    this->_grabbed_connection = this->knot->grabbed_signal.connect(sigc::bind(sigc::ptr_fun(gr_knot_grabbed_handler), this));
+    this->_mousedown_connection = this->knot->mousedown_signal.connect(sigc::bind(sigc::ptr_fun(gr_knot_mousedown_handler), this));
     this->_ungrabbed_connection = this->knot->ungrabbed_signal.connect(sigc::bind(sigc::ptr_fun(gr_knot_ungrabbed_handler), this));
 
     // add the initial draggable
@@ -1712,7 +1712,7 @@ GrDragger::~GrDragger()
     this->_moved_connection.disconnect();
     this->_clicked_connection.disconnect();
     this->_doubleclicked_connection.disconnect();
-    this->_grabbed_connection.disconnect();
+    this->_mousedown_connection.disconnect();
     this->_ungrabbed_connection.disconnect();
 
     /* unref should call destroy */
diff --git a/src/gradient-drag.h b/src/gradient-drag.h
index b4a64c78d..1fe2fb3f0 100644
--- a/src/gradient-drag.h
+++ b/src/gradient-drag.h
@@ -130,7 +130,7 @@ private:
     sigc::connection _moved_connection;
     sigc::connection _clicked_connection;
     sigc::connection _doubleclicked_connection;
-    sigc::connection _grabbed_connection;
+    sigc::connection _mousedown_connection;
     sigc::connection _ungrabbed_connection;
 };
 
diff --git a/src/knot.cpp b/src/knot.cpp
index c04206dee..50fa73391 100644
--- a/src/knot.cpp
+++ b/src/knot.cpp
@@ -214,7 +214,7 @@ static int sp_knot_handler(SPCanvasItem */*item*/, GdkEvent *event, SPKnot *knot
         if ((event->button.button == 1) && knot->desktop && knot->desktop->event_context && !knot->desktop->event_context->space_panning) {
             Geom::Point const p = knot->desktop->w2d(Geom::Point(event->button.x, event->button.y));
             knot->startDragging(p, (gint) event->button.x, (gint) event->button.y, event->button.time);
-            knot->grabbed_signal.emit(knot, event->button.state);
+            knot->mousedown_signal.emit(knot, event->button.state);
             consumed = TRUE;
         }
         break;
@@ -241,7 +241,6 @@ static int sp_knot_handler(SPCanvasItem */*item*/, GdkEvent *event, SPKnot *knot
 
                 if (moved) {
                     knot->setFlag(SP_KNOT_DRAGGING, FALSE);
-
                     knot->ungrabbed_signal.emit(knot, event->button.state);
                 } else {
                     knot->click_signal.emit(knot, event->button.state);
@@ -277,6 +276,7 @@ static int sp_knot_handler(SPCanvasItem */*item*/, GdkEvent *event, SPKnot *knot
 
             if (!moved) {
                 knot->setFlag(SP_KNOT_DRAGGING, TRUE);
+                knot->grabbed_signal.emit(knot, event->button.state);
             }
 
             sp_event_context_snap_delay_handler(knot->desktop->event_context, NULL, knot, (GdkEventMotion *)event, Inkscape::UI::Tools::DelayedSnapEvent::KNOT_HANDLER);
diff --git a/src/knot.h b/src/knot.h
index 954ddd8a6..0a0ce73d2 100644
--- a/src/knot.h
+++ b/src/knot.h
@@ -79,6 +79,7 @@ public:
     // be able to figure that out
     sigc::signal<void, SPKnot *, unsigned int> click_signal;
     sigc::signal<void, SPKnot*, unsigned int> doubleclicked_signal;
+    sigc::signal<void, SPKnot*, unsigned int> mousedown_signal;
     sigc::signal<void, SPKnot*, unsigned int> grabbed_signal;
     sigc::signal<void, SPKnot *, unsigned int> ungrabbed_signal;
     sigc::signal<void, SPKnot *, Geom::Point const &, unsigned int> moved_signal;