Fix middle-mouse-button-zooming in node-context with snap-delay enabled

diff --git a/src/event-context.cpp b/src/event-context.cpp
index bf98d98d3d6af222cfe1c8d55de34ab1b201e5fc..88b17e0011b942aea62c47d84b2e47094a54d54e 100644 (file)
--- a/src/event-context.cpp
+++ b/src/event-context.cpp
@@ -1180,6 +1180,14 @@ void sp_event_context_snap_delay_handler(SPEventContext *ec, SPItem* const item,
     bool const c2 = event->state & GDK_BUTTON3_MASK; // pressed, e.g. when scrolling with the middle mouse button; if we do then
                                                                                                     // Inkscape will get stuck in an unresponsive state
 
+    if (c1 || c2) {
+       // Make sure that we don't send any pending snap events to a context if we know in advance
+       // that we're not going to snap any way (e.g. while scrolling with middle mouse button)
+       // Any motion event might affect the state of the context, leading to unexpected behavior
+       delete ec->_delayed_snap_event;
+       ec->_delayed_snap_event = NULL;
+    }
+
     if (ec->_snap_window_open && !c1 && !c2 && ec->desktop && ec->desktop->namedview->snap_manager.snapprefs.getSnapEnabledGlobally()) {
        // Snap when speed drops below e.g. 0.02 px/msec, or when no motion events have occurred for some period.
                // i.e. snap when we're at stand still. A speed threshold enforces snapping for tablets, which might never