From 9ca836d1ea17af8888e89925750447996c9860ff Mon Sep 17 00:00:00 2001
From: Mike Williams <mike@mikebwilliams.com>
Date: Fri, 24 Sep 2021 13:14:08 -0400
Subject: [PATCH] Tools: Respect system drag

Also remove the time-based aspect. We aren't all super speed clickers.

Fixes: https://gitlab.com/kicad/code/kicad/-/issues/8765
---
 common/tool/tool_dispatcher.cpp | 42 ++++++++++++++++-----------------
 include/tool/tool_dispatcher.h  |  6 +++++
 2 files changed, 26 insertions(+), 22 deletions(-)

diff --git a/common/tool/tool_dispatcher.cpp b/common/tool/tool_dispatcher.cpp
index 2382e81ffd..26e69d1477 100644
--- a/common/tool/tool_dispatcher.cpp
+++ b/common/tool/tool_dispatcher.cpp
@@ -42,6 +42,7 @@
 #include <core/optional.h>
 #include <wx/log.h>
 #include <wx/stc/stc.h>
+#include <wx/settings.h>
 #include <kiplatform/app.h>
 #include <kiplatform/ui.h>
 
@@ -52,7 +53,6 @@ struct TOOL_DISPATCHER::BUTTON_STATE
                  const wxEventType& aUpEvent, const wxEventType& aDblClickEvent ) :
         dragging( false ),
         pressed( false ),
-        dragMaxDelta( 0.0f ),
         button( aButton ),
         downEvent( aDownEvent ),
         upEvent( aUpEvent ),
@@ -71,10 +71,6 @@ struct TOOL_DISPATCHER::BUTTON_STATE
     ///< Point where click event has occurred.
     VECTOR2D downPosition;
 
-    ///< Difference between drag origin point and current mouse position (expressed as distance in
-    ///< pixels).
-    double dragMaxDelta;
-
     ///< Determines the mouse button for which information are stored.
     TOOL_MOUSE_BUTTONS button;
 
@@ -126,6 +122,12 @@ struct TOOL_DISPATCHER::BUTTON_STATE
 TOOL_DISPATCHER::TOOL_DISPATCHER( TOOL_MANAGER* aToolMgr ) :
     m_toolMgr( aToolMgr )
 {
+    m_sysDragMinX = wxSystemSettings::GetMetric( wxSYS_DRAG_X );
+    m_sysDragMinY = wxSystemSettings::GetMetric( wxSYS_DRAG_Y );
+
+    m_sysDragMinX = m_sysDragMinX != -1 ? m_sysDragMinX : DragDistanceThreshold;
+    m_sysDragMinY = m_sysDragMinY != -1 ? m_sysDragMinY : DragDistanceThreshold;
+
     m_buttons.push_back( new BUTTON_STATE( BUT_LEFT, wxEVT_LEFT_DOWN,
                          wxEVT_LEFT_UP, wxEVT_LEFT_DCLICK ) );
     m_buttons.push_back( new BUTTON_STATE( BUT_RIGHT, wxEVT_RIGHT_DOWN,
@@ -192,7 +194,6 @@ bool TOOL_DISPATCHER::handleMouseButton( wxEvent& aEvent, int aIndex, bool aMoti
             st->dragOrigin = m_lastMousePos;
 
         st->downPosition = m_lastMousePos;
-        st->dragMaxDelta = 0;
         st->pressed = true;
         evt = TOOL_EVENT( TC_MOUSE, TA_MOUSE_DOWN, args );
     }
@@ -201,16 +202,7 @@ bool TOOL_DISPATCHER::handleMouseButton( wxEvent& aEvent, int aIndex, bool aMoti
         st->pressed = false;
 
         if( st->dragging )
-        {
-            wxLongLong t = wxGetLocalTimeMillis();
-
-            // Determine if it was just a single click or beginning of dragging
-            if( t - st->downTimestamp < DragTimeThreshold &&
-                    st->dragMaxDelta < DragDistanceThreshold )
-                isClick = true;
-            else
-                evt = TOOL_EVENT( TC_MOUSE, TA_MOUSE_UP, args );
-        }
+            evt = TOOL_EVENT( TC_MOUSE, TA_MOUSE_UP, args );
         else
             isClick = true;
 
@@ -226,14 +218,20 @@ bool TOOL_DISPATCHER::handleMouseButton( wxEvent& aEvent, int aIndex, bool aMoti
 
     if( st->pressed && aMotion )
     {
-        st->dragging = true;
-        double dragPixelDistance =
-            getView()->ToScreen( m_lastMousePos - st->dragOrigin, false ).EuclideanNorm();
-        st->dragMaxDelta = std::max( st->dragMaxDelta, dragPixelDistance );
+        if( !st->dragging )
+        {
+#ifdef __WXMAC__
+            if( wxGetLocalTimeMillis() - st->downTimestamp > DragTimeThreshold )
+                st->dragging = true;
+#else
+            VECTOR2D offset = getView()->ToScreen( m_lastMousePos - st->dragOrigin, false );
 
-        wxLongLong t = wxGetLocalTimeMillis();
+            if( abs( offset.x ) > m_sysDragMinX || abs( offset.y ) > m_sysDragMinY )
+                st->dragging = true;
+#endif
+        }
 
-        if( t - st->downTimestamp > DragTimeThreshold || st->dragMaxDelta > DragDistanceThreshold )
+        if( st->dragging )
         {
             evt = TOOL_EVENT( TC_MOUSE, TA_MOUSE_DRAG, args );
             evt->setMouseDragOrigin( st->dragOrigin );
diff --git a/include/tool/tool_dispatcher.h b/include/tool/tool_dispatcher.h
index 95bccac563..5ef74100b6 100644
--- a/include/tool/tool_dispatcher.h
+++ b/include/tool/tool_dispatcher.h
@@ -86,8 +86,14 @@ private:
 
     ///< The distance threshold for mouse cursor that distinguishes between a single mouse click
     ///< and a beginning of drag event (expressed in screen pixels).
+    ///< System drag preferences take precedence if available
     static const int DragDistanceThreshold = 8;
 
+    ///< Mininum distance before drag is activated in the X axis
+    int m_sysDragMinX;
+    ///< Maximum distance before drag is activated in the Y axis
+    int m_sysDragMinY;
+
     ///< Handles mouse related events (click, motion, dragging).
     bool handleMouseButton( wxEvent& aEvent, int aIndex, bool aMotion );