placement_tool.cpp

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/*
 * This program source code file is part of KiCad, a free EDA CAD application.
 *
 * Copyright (C) 2014-2016 CERN
 * Copyright (C) 2021-2022 KiCad Developers, see AUTHORS.txt for contributors.
 * @author Maciej Suminski <[email protected]>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
 */
#include "tool/selection.h"
#include "placement_tool.h"
#include "pcb_actions.h"
#include "pcb_selection_tool.h"
 
#include <ratsnest/ratsnest_data.h>
#include <tool/tool_manager.h>
 
#include <pcb_edit_frame.h>
#include <board.h>
#include <board_commit.h>
#include <bitmaps.h>
 
#include <menus_helpers.h>
 
 
ALIGN_DISTRIBUTE_TOOL::ALIGN_DISTRIBUTE_TOOL() :
 TOOL_INTERACTIVE( "pcbnew.Placement" ),
 m_selectionTool( nullptr ),
 m_placementMenu( nullptr ),
 m_frame( nullptr )
{
}
 
ALIGN_DISTRIBUTE_TOOL::~ALIGN_DISTRIBUTE_TOOL()
{
 delete m_placementMenu;
}
 
 
bool ALIGN_DISTRIBUTE_TOOL::Init()
{
 // Find the selection tool, so they can cooperate
 m_selectionTool = m_toolMgr->GetTool<PCB_SELECTION_TOOL>();
 m_frame = getEditFrame<PCB_BASE_FRAME>();
 
 // Create a context menu and make it available through selection tool
 m_placementMenu = new ACTION_MENU( true, this );
 m_placementMenu->SetIcon( BITMAPS::align_items );
 m_placementMenu->SetTitle( _( "Align/Distribute" ) );
 
  // Add all align/distribute commands
 m_placementMenu->Add( PCB_ACTIONS::alignLeft );
 m_placementMenu->Add( PCB_ACTIONS::alignCenterX );
 m_placementMenu->Add( PCB_ACTIONS::alignRight );
 
 m_placementMenu->AppendSeparator();
 m_placementMenu->Add( PCB_ACTIONS::alignTop );
 m_placementMenu->Add( PCB_ACTIONS::alignCenterY );
 m_placementMenu->Add( PCB_ACTIONS::alignBottom );
 
 m_placementMenu->AppendSeparator();
 m_placementMenu->Add( PCB_ACTIONS::distributeHorizontally );
 m_placementMenu->Add( PCB_ACTIONS::distributeVertically );
 
 CONDITIONAL_MENU& selToolMenu = m_selectionTool->GetToolMenu().GetMenu();
 selToolMenu.AddMenu( m_placementMenu, SELECTION_CONDITIONS::MoreThan( 1 ), 100 );
 
 return true;
}
 
 
template <class T>
std::vector<std::pair<BOARD_ITEM*, BOX2I>> GetBoundingBoxes( const T& aItems )
{
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> rects;
 
 for( EDA_ITEM* item : aItems )
 {
 BOARD_ITEM* boardItem = static_cast<BOARD_ITEM*>( item );
 
 if( item->Type() == PCB_FOOTPRINT_T )
 {
 FOOTPRINT* footprint = static_cast<FOOTPRINT*>( item );
 rects.emplace_back( std::make_pair( footprint,
 footprint->GetBoundingBox( false, false ) ) );
 }
 else
 {
 rects.emplace_back( std::make_pair( boardItem, boardItem->GetBoundingBox() ) );
 }
 }
 
 return rects;
}
 
 
template< typename T >
int ALIGN_DISTRIBUTE_TOOL::selectTarget( std::vector<std::pair<BOARD_ITEM*, BOX2I>>& aItems,
 std::vector<std::pair<BOARD_ITEM*, BOX2I>>& aLocked,
 T aGetValue )
{
 VECTOR2I curPos = getViewControls()->GetCursorPosition();
 
 // Prefer locked items to unlocked items.
 // Secondly, prefer items under the cursor to other items.
 
 if( aLocked.size() >= 1 )
 {
 for( const std::pair<BOARD_ITEM*, BOX2I>& item : aLocked )
 {
 if( item.second.Contains( curPos ) )
 return aGetValue( item );
 }
 
 return aGetValue( aLocked.front() );
 }
 
 for( const std::pair<BOARD_ITEM*, BOX2I>& item : aItems )
 {
 if( item.second.Contains( curPos ) )
 return aGetValue( item );
 }
 
 return aGetValue( aItems.front() );
}
 
 
template< typename T >
size_t ALIGN_DISTRIBUTE_TOOL::GetSelections( std::vector<std::pair<BOARD_ITEM*, BOX2I>>& aItemsToAlign,
 std::vector<std::pair<BOARD_ITEM*, BOX2I>>& aLockedItems,
 T aCompare )
{
 PCB_SELECTION& selection = m_selectionTool->RequestSelection(
 []( const VECTOR2I& aPt, GENERAL_COLLECTOR& aCollector, PCB_SELECTION_TOOL* sTool )
 {
 // Iterate from the back so we don't have to worry about removals.
 for( int i = aCollector.GetCount() - 1; i >= 0; --i )
 {
 BOARD_ITEM* item = aCollector[i];
 
 if( item->Type() == PCB_MARKER_T )
 aCollector.Remove( item );
 }
 } );
 
 std::vector<BOARD_ITEM*> lockedItems;
 std::vector<BOARD_ITEM*> itemsToAlign;
 
 for( EDA_ITEM* item : selection )
 {
 BOARD_ITEM* boardItem = static_cast<BOARD_ITEM*>( item );
 
 // We do not lock items in the footprint editor
 if( boardItem->IsLocked() && m_frame->IsType( FRAME_PCB_EDITOR ) )
 {
 // Locking a pad but not the footprint means that we align the footprint using
 // the pad position. So we test for footprint locking here
 if( boardItem->Type() == PCB_PAD_T && !boardItem->GetParent()->IsLocked() )
 {
 itemsToAlign.push_back( boardItem );
 }
 else
 {
 lockedItems.push_back( boardItem );
 }
 }
 else
 itemsToAlign.push_back( boardItem );
 }
 
 aItemsToAlign = GetBoundingBoxes( itemsToAlign );
 aLockedItems = GetBoundingBoxes( lockedItems );
 std::sort( aItemsToAlign.begin(), aItemsToAlign.end(), aCompare );
 std::sort( aLockedItems.begin(), aLockedItems.end(), aCompare );
 
 return aItemsToAlign.size();
}
 
 
int ALIGN_DISTRIBUTE_TOOL::AlignTop( const TOOL_EVENT& aEvent )
{
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> itemsToAlign;
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> locked_items;
 
 if( !GetSelections( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.GetTop() < right.second.GetTop() );
 } ) )
 {
 return 0;
 }
 
 BOARD_COMMIT commit( m_frame );
 
 int targetTop = selectTarget( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I>& aVal )
 {
 return aVal.second.GetTop();
 } );
 
 // Move the selected items
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : itemsToAlign )
 {
 BOARD_ITEM* item = i.first;
 int difference = targetTop - i.second.GetTop();
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 commit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( 0, difference ) );
 }
 
 commit.Push( _( "Align to top" ) );
 
 return 0;
}
 
 
int ALIGN_DISTRIBUTE_TOOL::AlignBottom( const TOOL_EVENT& aEvent )
{
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> itemsToAlign;
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> locked_items;
 
 if( !GetSelections( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.GetBottom() > right.second.GetBottom() );
 } ) )
 {
 return 0;
 }
 
 BOARD_COMMIT commit( m_frame );
 
 int targetBottom = selectTarget( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I>& aVal )
 {
 return aVal.second.GetBottom();
 } );
 
 // Move the selected items
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : itemsToAlign )
 {
 int difference = targetBottom - i.second.GetBottom();
 BOARD_ITEM* item = i.first;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 commit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( 0, difference ) );
 }
 
 commit.Push( _( "Align to bottom" ) );
 
 return 0;
}
 
 
int ALIGN_DISTRIBUTE_TOOL::AlignLeft( const TOOL_EVENT& aEvent )
{
 // Because this tool uses bounding boxes and they aren't mirrored even when
 // the view is mirrored, we need to call the other one if mirrored.
 if( getView()->IsMirroredX() )
 {
 return doAlignRight();
 }
 else
 {
 return doAlignLeft();
 }
}
 
 
int ALIGN_DISTRIBUTE_TOOL::doAlignLeft()
{
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> itemsToAlign;
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> locked_items;
 
 if( !GetSelections( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.GetLeft() < right.second.GetLeft() );
 } ) )
 {
 return 0;
 }
 
 BOARD_COMMIT commit( m_frame );
 
 int targetLeft = selectTarget( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I>& aVal )
 {
 return aVal.second.GetLeft();
 } );
 
 // Move the selected items
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : itemsToAlign )
 {
 int difference = targetLeft - i.second.GetLeft();
 BOARD_ITEM* item = i.first;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 commit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( difference, 0 ) );
 }
 
 commit.Push( _( "Align to left" ) );
 
 return 0;
}
 
 
int ALIGN_DISTRIBUTE_TOOL::AlignRight( const TOOL_EVENT& aEvent )
{
 // Because this tool uses bounding boxes and they aren't mirrored even when
 // the view is mirrored, we need to call the other one if mirrored.
 if( getView()->IsMirroredX() )
 {
 return doAlignLeft();
 }
 else
 {
 return doAlignRight();
 }
}
 
 
int ALIGN_DISTRIBUTE_TOOL::doAlignRight()
{
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> itemsToAlign;
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> locked_items;
 
 if( !GetSelections( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.GetRight() > right.second.GetRight() );
 } ) )
 {
 return 0;
 }
 
 BOARD_COMMIT commit( m_frame );
 
 int targetRight = selectTarget( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I>& aVal )
 {
 return aVal.second.GetRight();
 } );
 
 // Move the selected items
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : itemsToAlign )
 {
 int difference = targetRight - i.second.GetRight();
 BOARD_ITEM* item = i.first;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 commit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( difference, 0 ) );
 }
 
 commit.Push( _( "Align to right" ) );
 
 return 0;
}
 
 
int ALIGN_DISTRIBUTE_TOOL::AlignCenterX( const TOOL_EVENT& aEvent )
{
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> itemsToAlign;
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> locked_items;
 
 if( !GetSelections( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.Centre().x < right.second.Centre().x );
 } ) )
 {
 return 0;
 }
 
 BOARD_COMMIT commit( m_frame );
 
 int targetX = selectTarget( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I>& aVal )
 {
 return aVal.second.Centre().x;
 } );
 
 // Move the selected items
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : itemsToAlign )
 {
 int difference = targetX - i.second.Centre().x;
 BOARD_ITEM* item = i.first;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 commit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( difference, 0 ) );
 }
 
 commit.Push( _( "Align to middle" ) );
 
 return 0;
}
 
 
int ALIGN_DISTRIBUTE_TOOL::AlignCenterY( const TOOL_EVENT& aEvent )
{
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> itemsToAlign;
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> locked_items;
 
 if( !GetSelections( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.Centre().y < right.second.Centre().y );
 } ) )
 {
 return 0;
 }
 
 BOARD_COMMIT commit( m_frame );
 
 int targetY = selectTarget( itemsToAlign, locked_items,
 []( const std::pair<BOARD_ITEM*, BOX2I>& aVal )
 {
 return aVal.second.Centre().y;
 } );
 
 // Move the selected items
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : itemsToAlign )
 {
 int difference = targetY - i.second.Centre().y;
 BOARD_ITEM* item = i.first;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 commit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( 0, difference ) );
 }
 
 commit.Push( _( "Align to center" ) );
 
 return 0;
}
 
 
int ALIGN_DISTRIBUTE_TOOL::DistributeHorizontally( const TOOL_EVENT& aEvent )
{
 PCB_SELECTION& selection = m_selectionTool->RequestSelection(
 []( const VECTOR2I& aPt, GENERAL_COLLECTOR& aCollector, PCB_SELECTION_TOOL* sTool )
 {
 // Iterate from the back so we don't have to worry about removals.
 for( int i = aCollector.GetCount() - 1; i >= 0; --i )
 {
 BOARD_ITEM* item = aCollector[i];
 
 if( item->Type() == PCB_MARKER_T )
 aCollector.Remove( item );
 }
 },
 m_frame->IsType( FRAME_PCB_EDITOR ) /* prompt user regarding locked items */ );
 
 if( selection.Size() <= 1 )
 return 0;
 
 BOARD_COMMIT commit( m_frame );
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> itemsToDistribute = GetBoundingBoxes( selection );
 
 // find the last item by reverse sorting
 std::sort( itemsToDistribute.begin(), itemsToDistribute.end(),
 [] ( const std::pair<BOARD_ITEM*, BOX2I> left,
 const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.GetRight() > right.second.GetRight() );
 } );
 
 BOARD_ITEM* lastItem = itemsToDistribute.begin()->first;
 const int maxRight = itemsToDistribute.begin()->second.GetRight();
 
 // sort to get starting order
 std::sort( itemsToDistribute.begin(), itemsToDistribute.end(),
 [] ( const std::pair<BOARD_ITEM*, BOX2I> left,
 const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.GetX() < right.second.GetX() );
 } );
 
 const int minX = itemsToDistribute.begin()->second.GetX();
 int totalGap = maxRight - minX;
 int totalWidth = 0;
 
 for( const auto& [ item, rect ] : itemsToDistribute )
 totalWidth += rect.GetWidth();
 
 if( totalGap < totalWidth )
 {
 // the width of the items exceeds the gap (overlapping items) -> use center point spacing
 doDistributeCentersHorizontally( itemsToDistribute, commit );
 }
 else
 {
 totalGap -= totalWidth;
 doDistributeGapsHorizontally( itemsToDistribute, commit, lastItem, totalGap );
 }
 
 commit.Push( _( "Distribute horizontally" ) );
 
 return 0;
}
 
 
void ALIGN_DISTRIBUTE_TOOL::doDistributeGapsHorizontally( std::vector<std::pair<BOARD_ITEM*, BOX2I>>& aItems,
 BOARD_COMMIT& aCommit,
 const BOARD_ITEM* lastItem,
 int totalGap ) const
{
 const int itemGap = totalGap / ( aItems.size() - 1 );
 int targetX = aItems.begin()->second.GetX();
 
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : aItems )
 {
 BOARD_ITEM* item = i.first;
 
 // cover the corner case where the last item is wider than the previous item and gap
 if( lastItem == item )
 continue;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 int difference = targetX - i.second.GetX();
 aCommit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( difference, 0 ) );
 targetX += ( i.second.GetWidth() + itemGap );
 }
}
 
 
void ALIGN_DISTRIBUTE_TOOL::doDistributeCentersHorizontally( std::vector<std::pair<BOARD_ITEM*, BOX2I>> &aItems,
 BOARD_COMMIT& aCommit ) const
{
 std::sort( aItems.begin(), aItems.end(),
 [] ( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.Centre().x < right.second.Centre().x );
 } );
 
 const int totalGap = ( aItems.end() - 1 )->second.Centre().x
 - aItems.begin()->second.Centre().x;
 const int itemGap = totalGap / ( aItems.size() - 1 );
 int targetX = aItems.begin()->second.Centre().x;
 
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : aItems )
 {
 BOARD_ITEM* item = i.first;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 int difference = targetX - i.second.Centre().x;
 aCommit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( difference, 0 ) );
 targetX += ( itemGap );
 }
}
 
 
int ALIGN_DISTRIBUTE_TOOL::DistributeVertically( const TOOL_EVENT& aEvent )
{
 PCB_SELECTION& selection = m_selectionTool->RequestSelection(
 []( const VECTOR2I& aPt, GENERAL_COLLECTOR& aCollector, PCB_SELECTION_TOOL* sTool )
 {
 // Iterate from the back so we don't have to worry about removals.
 for( int i = aCollector.GetCount() - 1; i >= 0; --i )
 {
 BOARD_ITEM* item = aCollector[i];
 
 if( item->Type() == PCB_MARKER_T )
 aCollector.Remove( item );
 }
 },
 m_frame->IsType( FRAME_PCB_EDITOR ) /* prompt user regarding locked items */ );
 
 if( selection.Size() <= 1 )
 return 0;
 
 BOARD_COMMIT commit( m_frame );
 std::vector<std::pair<BOARD_ITEM*, BOX2I>> itemsToDistribute = GetBoundingBoxes( selection );
 
 // find the last item by reverse sorting
 std::sort( itemsToDistribute.begin(), itemsToDistribute.end(),
 [] ( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.GetBottom() > right.second.GetBottom() );
 } );
 
 BOARD_ITEM* lastItem = itemsToDistribute.begin()->first;
 const int maxBottom = itemsToDistribute.begin()->second.GetBottom();
 
 // sort to get starting order
 std::sort( itemsToDistribute.begin(), itemsToDistribute.end(),
 [] ( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.Centre().y < right.second.Centre().y );
 } );
 
 int minY = itemsToDistribute.begin()->second.GetY();
 int totalGap = maxBottom - minY;
 int totalHeight = 0;
 
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : itemsToDistribute )
 totalHeight += i.second.GetHeight();
 
 if( totalGap < totalHeight )
 {
 // the width of the items exceeds the gap (overlapping items) -> use center point spacing
 doDistributeCentersVertically( itemsToDistribute, commit );
 }
 else
 {
 totalGap -= totalHeight;
 doDistributeGapsVertically( itemsToDistribute, commit, lastItem, totalGap );
 }
 
 commit.Push( _( "Distribute vertically" ) );
 
 return 0;
}
 
 
void ALIGN_DISTRIBUTE_TOOL::doDistributeGapsVertically( std::vector<std::pair<BOARD_ITEM*, BOX2I>>& aItems,
 BOARD_COMMIT& aCommit,
 const BOARD_ITEM* lastItem,
 int totalGap ) const
{
 const int itemGap = totalGap / ( aItems.size() - 1 );
 int targetY = aItems.begin()->second.GetY();
 
 for( std::pair<BOARD_ITEM*, BOX2I>& i : aItems )
 {
 BOARD_ITEM* item = i.first;
 
 // cover the corner case where the last item is wider than the previous item and gap
 if( lastItem == item )
 continue;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 int difference = targetY - i.second.GetY();
 aCommit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( 0, difference ) );
 targetY += ( i.second.GetHeight() + itemGap );
 }
}
 
 
void ALIGN_DISTRIBUTE_TOOL::doDistributeCentersVertically( std::vector<std::pair<BOARD_ITEM*, BOX2I>>& aItems,
 BOARD_COMMIT& aCommit ) const
{
 std::sort( aItems.begin(), aItems.end(),
 [] ( const std::pair<BOARD_ITEM*, BOX2I> left, const std::pair<BOARD_ITEM*, BOX2I> right)
 {
 return ( left.second.Centre().y < right.second.Centre().y );
 } );
 
 const int totalGap = ( aItems.end() - 1 )->second.Centre().y
 - aItems.begin()->second.Centre().y;
 const int itemGap = totalGap / ( aItems.size() - 1 );
 int targetY = aItems.begin()->second.Centre().y;
 
 for( const std::pair<BOARD_ITEM*, BOX2I>& i : aItems )
 {
 BOARD_ITEM* item = i.first;
 
 if( item->GetParent() && item->GetParent()->IsSelected() )
 continue;
 
 // Don't move a pad by itself unless editing the footprint
 if( item->Type() == PCB_PAD_T && m_frame->IsType( FRAME_PCB_EDITOR ) )
 item = item->GetParent();
 
 int difference = targetY - i.second.Centre().y;
 aCommit.Stage( item, CHT_MODIFY );
 item->Move( VECTOR2I( 0, difference ) );
 targetY += ( itemGap );
 }
}
 
 
void ALIGN_DISTRIBUTE_TOOL::setTransitions()
{
 Go( &ALIGN_DISTRIBUTE_TOOL::AlignTop, PCB_ACTIONS::alignTop.MakeEvent() );
 Go( &ALIGN_DISTRIBUTE_TOOL::AlignBottom, PCB_ACTIONS::alignBottom.MakeEvent() );
 Go( &ALIGN_DISTRIBUTE_TOOL::AlignLeft, PCB_ACTIONS::alignLeft.MakeEvent() );
 Go( &ALIGN_DISTRIBUTE_TOOL::AlignRight, PCB_ACTIONS::alignRight.MakeEvent() );
 Go( &ALIGN_DISTRIBUTE_TOOL::AlignCenterX, PCB_ACTIONS::alignCenterX.MakeEvent() );
 Go( &ALIGN_DISTRIBUTE_TOOL::AlignCenterY, PCB_ACTIONS::alignCenterY.MakeEvent() );
 
 Go( &ALIGN_DISTRIBUTE_TOOL::DistributeHorizontally,
 PCB_ACTIONS::distributeHorizontally.MakeEvent() );
 Go( &ALIGN_DISTRIBUTE_TOOL::DistributeVertically,
 PCB_ACTIONS::distributeVertically.MakeEvent() );
}