From 95a6e8deb2afeb6026ce1166bbbc71a547fc735a Mon Sep 17 00:00:00 2001
From: Maciej Suminski <maciej.suminski@cern.ch>
Date: Mon, 23 Jun 2014 16:12:59 +0200
Subject: [PATCH] Dragging items by their origin is optional (activated by
 dragging elements with Ctrl held).

---
 pcbnew/tools/edit_tool.cpp | 30 +++++++++++++++++++++++++-----
 pcbnew/tools/edit_tool.h   |  3 +++
 2 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/pcbnew/tools/edit_tool.cpp b/pcbnew/tools/edit_tool.cpp
index 93e878031c..db08a607a5 100644
--- a/pcbnew/tools/edit_tool.cpp
+++ b/pcbnew/tools/edit_tool.cpp
@@ -147,7 +147,7 @@ int EDIT_TOOL::Main( TOOL_EVENT& aEvent )
 
                 // Drag items to the current cursor position
                 for( unsigned int i = 0; i < selection.items.GetCount(); ++i )
-                    selection.Item<BOARD_ITEM>( i )->Move( movement );
+                    selection.Item<BOARD_ITEM>( i )->Move( movement + m_offset );
 
                 updateRatsnest( true );
             }
@@ -157,9 +157,21 @@ int EDIT_TOOL::Main( TOOL_EVENT& aEvent )
                 editFrame->OnModify();
                 editFrame->SaveCopyInUndoList( selection.items, UR_CHANGED );
 
-                // Set the current cursor position to the first dragged item origin, so the
-                // movement vector could be computed later
-                m_cursor = VECTOR2I( selection.Item<BOARD_ITEM>( 0 )->GetPosition() );
+                if( evt->Modifier( MD_CTRL ) )
+                {
+                    // Set the current cursor position to the first dragged item origin, so the
+                    // movement vector could be computed later
+                    m_cursor = VECTOR2I( selection.Item<BOARD_ITEM>( 0 )->GetPosition() );
+                    m_offset.x = 0;
+                    m_offset.y = 0;
+                }
+                else
+                {
+                    // Update dragging offset (distance between cursor and the first dragged item)
+                    m_offset = static_cast<BOARD_ITEM*>( selection.items.GetPickedItem( 0 ) )->GetPosition() -
+                                                         wxPoint( m_cursor.x, m_cursor.y );
+                }
+
                 m_dragging = true;
             }
 
@@ -309,6 +321,10 @@ int EDIT_TOOL::Rotate( TOOL_EVENT& aEvent )
 
     updateRatsnest( m_dragging );
 
+    // Update dragging offset (distance between cursor and the first dragged item)
+    m_offset = static_cast<BOARD_ITEM*>( selection.items.GetPickedItem( 0 ) )->GetPosition() -
+                                         rotatePoint;
+
     if( m_dragging )
         selection.group->ViewUpdate( KIGFX::VIEW_ITEM::GEOMETRY );
     else
@@ -359,6 +375,10 @@ int EDIT_TOOL::Flip( TOOL_EVENT& aEvent )
 
     updateRatsnest( m_dragging );
 
+    // Update dragging offset (distance between cursor and the first dragged item)
+    m_offset = static_cast<BOARD_ITEM*>( selection.items.GetPickedItem( 0 ) )->GetPosition() -
+                                         flipPoint;
+
     if( m_dragging )
         selection.group->ViewUpdate( KIGFX::VIEW_ITEM::GEOMETRY );
     else
@@ -491,7 +511,7 @@ wxPoint EDIT_TOOL::getModificationPoint( const SELECTION_TOOL::SELECTION& aSelec
 {
     if( aSelection.Size() == 1 )
     {
-        return aSelection.Item<BOARD_ITEM>( 0 )->GetPosition();
+        return aSelection.Item<BOARD_ITEM>( 0 )->GetPosition() - m_offset;
     }
     else
     {
diff --git a/pcbnew/tools/edit_tool.h b/pcbnew/tools/edit_tool.h
index fb74135b86..207e446493 100644
--- a/pcbnew/tools/edit_tool.h
+++ b/pcbnew/tools/edit_tool.h
@@ -98,6 +98,9 @@ private:
     ///> Flag determining if anything is being dragged right now
     bool m_dragging;
 
+    ///> Offset from the dragged item's center (anchor)
+    wxPoint m_offset;
+
     ///> Last cursor position (needed for getModificationPoint() to avoid changes
     ///> of edit reference point).
     VECTOR2I m_cursor;