Added snap to grid drag behaviour

[pulseview.git] / pv / view / header.cpp

diff --git a/pv/view/header.cpp b/pv/view/header.cpp
index 00c4201cf39a28d0ee3e234b0f311e6838ab1a5b..976172137987e3780382a50a75e0eced462a2be7 100644 (file)
--- a/pv/view/header.cpp
+++ b/pv/view/header.cpp
@@ -155,10 +155,16 @@ void Header::mouseMoveEvent(QMouseEvent *event)
                const int delta = event->pos().y() - _mouse_down_point.y();
 
                BOOST_FOREACH(const shared_ptr<Signal> s, sigs)
-                       if(s->selected())
-                               s->set_v_offset(
+                       if(s->selected()) {
+                               const int y =
                                        _mouse_down_signal_offsets[s.get()] +
-                                       delta);
+                                       delta;
+                               const int y_snap =
+                                       ((y + View::SignalSnapGridSize / 2) /
+                                               View::SignalSnapGridSize) *
+                                               View::SignalSnapGridSize;
+                               s->set_v_offset(y_snap  );
+                       }
 
                signals_moved();
        }