From 55394f343d479a111ea9ff85c887dd4195778733 Mon Sep 17 00:00:00 2001
From: Jon Evans <jon@craftyjon.com>
Date: Mon, 28 Dec 2020 17:26:39 -0500
Subject: [PATCH] Don't use snapping for a selection interaction

Fixes https://gitlab.com/kicad/code/kicad/-/issues/6856
---
 pcbnew/tools/board_inspection_tool.cpp |  1 +
 pcbnew/tools/pcb_picker_tool.cpp       | 14 ++++++++++----
 pcbnew/tools/pcb_picker_tool.h         |  2 ++
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/pcbnew/tools/board_inspection_tool.cpp b/pcbnew/tools/board_inspection_tool.cpp
index 3fb19155ad..b74209a0bd 100644
--- a/pcbnew/tools/board_inspection_tool.cpp
+++ b/pcbnew/tools/board_inspection_tool.cpp
@@ -909,6 +909,7 @@ int BOARD_INSPECTION_TOOL::HighlightNetTool( const TOOL_EVENT& aEvent )
         } );
 
     picker->SetLayerSet( LSET::AllCuMask() );
+    picker->SetSnapping( false );
 
     m_toolMgr->RunAction( ACTIONS::pickerTool, true, &tool );
 
diff --git a/pcbnew/tools/pcb_picker_tool.cpp b/pcbnew/tools/pcb_picker_tool.cpp
index 01b33fdbc2..86aa07489a 100644
--- a/pcbnew/tools/pcb_picker_tool.cpp
+++ b/pcbnew/tools/pcb_picker_tool.cpp
@@ -61,15 +61,20 @@ int PCB_PICKER_TOOL::Main( const TOOL_EVENT& aEvent )
 
     // Set initial cursor
     setCursor();
+    VECTOR2D cursorPos;
 
     while( TOOL_EVENT* evt = Wait() )
     {
         setCursor();
+        cursorPos =  controls->GetMousePosition();
 
-        grid.SetSnap( !evt->Modifier( MD_SHIFT ) );
-        grid.SetUseGrid( getView()->GetGAL()->GetGridSnapping() && !evt->Modifier( MD_ALT ) );
-        VECTOR2I cursorPos = grid.BestSnapAnchor( controls->GetMousePosition(), nullptr );
-        controls->ForceCursorPosition(true, cursorPos );
+        if( m_snap )
+        {
+            grid.SetSnap( !evt->Modifier( MD_SHIFT ) );
+            grid.SetUseGrid( getView()->GetGAL()->GetGridSnapping() && !evt->Modifier( MD_ALT ) );
+            cursorPos = grid.BestSnapAnchor( cursorPos, nullptr );
+            controls->ForceCursorPosition( true, cursorPos );
+        }
 
         if( evt->IsCancelInteractive() || evt->IsActivate() )
         {
@@ -181,6 +186,7 @@ void PCB_PICKER_TOOL::reset()
 {
     m_layerMask = LSET::AllLayersMask();
     m_cursor    = KICURSOR::ARROW;
+    m_snap      = true;
 
     m_picked = NULLOPT;
     m_clickHandler = NULLOPT;
diff --git a/pcbnew/tools/pcb_picker_tool.h b/pcbnew/tools/pcb_picker_tool.h
index e40235975f..ed6100b5f1 100644
--- a/pcbnew/tools/pcb_picker_tool.h
+++ b/pcbnew/tools/pcb_picker_tool.h
@@ -66,6 +66,7 @@ public:
 
     inline void SetCursor( KICURSOR aCursor ) { m_cursor = aCursor; }
 
+    inline void SetSnapping( bool aSnap ) { m_snap = aSnap; }
     /**
      * Function SetClickHandler()
      * Sets a handler for mouse click event. Handler may decide to receive further click by
@@ -121,6 +122,7 @@ private:
     ///> The layer set to use for optional snapping
     LSET                  m_layerMask;
     KICURSOR              m_cursor;
+    bool                  m_snap;
 
     OPT<CLICK_HANDLER>    m_clickHandler;
     OPT<MOTION_HANDLER>   m_motionHandler;