pns_dp_meander_placer.cpp

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/*
 * KiRouter - a push-and-(sometimes-)shove PCB router
 *
 * Copyright (C) 2013-2014 CERN
 * Copyright (C) 2016-2023 KiCad Developers, see AUTHORS.txt for contributors.
 * Author: Tomasz Wlostowski <[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 3 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, see <http://www.gnu.org/licenses/>.
 */
 
#include <optional>
 
#include "pns_node.h"
#include "pns_itemset.h"
#include "pns_topology.h"
#include "pns_dp_meander_placer.h"
#include "pns_diff_pair.h"
#include "pns_router.h"
#include "pns_solid.h"
 
namespace PNS {
 
DP_MEANDER_PLACER::DP_MEANDER_PLACER( ROUTER* aRouter ) :
 MEANDER_PLACER_BASE( aRouter )
{
 m_world = nullptr;
 m_currentNode = nullptr;
 
 m_padToDieP = 0;
 m_padToDieN = 0;
 
 // Init temporary variables (do not leave uninitialized members)
 m_initialSegment = nullptr;
 m_lastLength = 0;
 m_lastStatus = TOO_SHORT;
}
 
 
DP_MEANDER_PLACER::~DP_MEANDER_PLACER()
{
}
 
 
const LINE DP_MEANDER_PLACER::Trace() const
{
 return m_currentTraceP;
}
 
 
const DIFF_PAIR& DP_MEANDER_PLACER::GetOriginPair()
{
 return m_originPair;
}
 
 
NODE* DP_MEANDER_PLACER::CurrentNode( bool aLoopsRemoved ) const
{
 if( !m_currentNode )
 return m_world;
 
 return m_currentNode;
}
 
 
bool DP_MEANDER_PLACER::Start( const VECTOR2I& aP, ITEM* aStartItem )
{
 if( !aStartItem || !aStartItem->OfKind( ITEM::SEGMENT_T | ITEM::ARC_T ) )
 {
 Router()->SetFailureReason( _( "Please select a track whose length you want to tune." ) );
 return false;
 }
 
 m_initialSegment = static_cast<LINKED_ITEM*>( aStartItem );
 m_currentNode = nullptr;
 m_currentStart = getSnappedStartPoint( m_initialSegment, aP );
 
 m_world = Router()->GetWorld()->Branch();
 
 TOPOLOGY topo( m_world );
 
 if( !topo.AssembleDiffPair( m_initialSegment, m_originPair ) )
 {
 Router()->SetFailureReason( _( "Unable to find complementary differential pair "
 "net for length tuning. Make sure the names of the nets "
 "belonging to a differential pair end with either _N/_P "
 "or +/-." ) );
 return false;
 }
 
 if( m_originPair.Gap() < 0 )
 m_originPair.SetGap( Router()->Sizes().DiffPairGap() );
 
 if( !m_originPair.PLine().SegmentCount() || !m_originPair.NLine().SegmentCount() )
 return false;
 
 m_tunedPathP = topo.AssembleTuningPath( m_originPair.PLine().GetLink( 0 ), &m_startPad_p, &m_endPad_p );
 
 m_padToDieP = 0;
 
 if( m_startPad_p )
 m_padToDieP += m_startPad_p->GetPadToDie();
 
 if( m_endPad_p )
 m_padToDieP += m_endPad_p->GetPadToDie();
 
 m_tunedPathN = topo.AssembleTuningPath( m_originPair.NLine().GetLink( 0 ), &m_startPad_n, &m_endPad_n );
 
 m_padToDieN = 0;
 
 if( m_startPad_n )
 m_padToDieN += m_startPad_n->GetPadToDie();
 
 if( m_endPad_n )
 m_padToDieN += m_endPad_n->GetPadToDie();
 
 m_world->Remove( m_originPair.PLine() );
 m_world->Remove( m_originPair.NLine() );
 
 m_currentWidth = m_originPair.Width();
 
 return true;
}
 
 
void DP_MEANDER_PLACER::release()
{
}
 
 
long long int DP_MEANDER_PLACER::origPathLength() const
{
 long long int totalP = m_padToDieP + lineLength( m_tunedPathP, m_startPad_p, m_endPad_p );
 long long int totalN = m_padToDieN + lineLength( m_tunedPathN, m_startPad_n, m_endPad_n );
 return std::max( totalP, totalN );
}
 
 
const SEG DP_MEANDER_PLACER::baselineSegment( const DIFF_PAIR::COUPLED_SEGMENTS& aCoupledSegs )
{
 const VECTOR2I a( ( aCoupledSegs.coupledP.A + aCoupledSegs.coupledN.A ) / 2 );
 const VECTOR2I b( ( aCoupledSegs.coupledP.B + aCoupledSegs.coupledN.B ) / 2 );
 
 return SEG( a, b );
}
 
 
bool DP_MEANDER_PLACER::pairOrientation( const DIFF_PAIR::COUPLED_SEGMENTS& aPair )
{
 VECTOR2I midp = ( aPair.coupledP.A + aPair.coupledN.A ) / 2;
 
 //DrawDebugPoint(midp, 6);
 
 return aPair.coupledP.Side( midp ) > 0;
}
 
 
bool DP_MEANDER_PLACER::Move( const VECTOR2I& aP, ITEM* aEndItem )
{
 if( m_currentStart == aP )
 return false;
 
 DIFF_PAIR::COUPLED_SEGMENTS_VEC coupledSegments;
 
 if( m_currentNode )
 delete m_currentNode;
 
 m_currentNode = m_world->Branch();
 
 SHAPE_LINE_CHAIN preP, tunedP, postP;
 SHAPE_LINE_CHAIN preN, tunedN, postN;
 
 m_originPair.CP().Split( m_currentStart, aP, preP, tunedP, postP );
 m_originPair.CN().Split( m_currentStart, aP, preN, tunedN, postN );
 
 auto updateStatus =
 [&]()
 {
 if( m_lastLength > m_settings.m_targetLength.Max() )
 m_lastStatus = TOO_LONG;
 else if( m_lastLength < m_settings.m_targetLength.Min() )
 m_lastStatus = TOO_SHORT;
 else
 m_lastStatus = TUNED;
 };
 
 DIFF_PAIR tuned( m_originPair );
 
 tuned.SetShape( tunedP, tunedN );
 
 tuned.CoupledSegmentPairs( coupledSegments );
 
 if( coupledSegments.size() == 0 )
 {
 // Tuning started at an uncoupled area of the DP; we won't get a valid result until the
 // cursor is moved far enough along a coupled area. Prevent the track from disappearing and
 // the length from being zero by just using the original.
 m_finalShapeP = m_originPair.CP();
 m_finalShapeN = m_originPair.CN();
 m_lastLength = origPathLength();
 updateStatus();
 
 return false;
 }
 
 m_result = MEANDERED_LINE( this, true );
 m_result.SetWidth( tuned.Width() );
 
 int offset = ( tuned.Gap() + tuned.Width() ) / 2;
 
 if( pairOrientation( coupledSegments[0] ) )
 offset *= -1;
 
 m_result.SetBaselineOffset( offset );
 
 for( const ITEM* item : m_tunedPathP.CItems() )
 {
 if( const LINE* l = dyn_cast<const LINE*>( item ) )
 {
 PNS_DBG( Dbg(), AddShape, &l->CLine(), YELLOW, 10000, wxT( "tuned-path-p" ) );
 
 m_router->GetInterface()->DisplayPathLine( l->CLine(), 1 );
 }
 }
 
 for( const ITEM* item : m_tunedPathN.CItems() )
 {
 if( const LINE* l = dyn_cast<const LINE*>( item ) )
 {
 PNS_DBG( Dbg(), AddShape, &l->CLine(), YELLOW, 10000, wxT( "tuned-path-n" ) );
 
 m_router->GetInterface()->DisplayPathLine( l->CLine(), 1 );
 }
 }
 
 int curIndexP = 0, curIndexN = 0;
 
 for( const DIFF_PAIR::COUPLED_SEGMENTS& sp : coupledSegments )
 {
 SEG base = baselineSegment( sp );
 bool side = false;
 
 if( m_settings.m_initialSide == 0 )
 side = base.Side( aP ) < 0;
 else
 side = m_settings.m_initialSide < 0;
 
 PNS_DBG( Dbg(), AddShape, base, GREEN, 10000, wxT( "dp-baseline" ) );
 
 while( sp.indexP >= curIndexP && curIndexP != -1 )
 {
 if( tunedP.IsArcSegment( curIndexP ) )
 {
 ssize_t arcIndex = tunedP.ArcIndex( curIndexP );
 
 m_result.AddArcAndPt( tunedP.Arc( arcIndex ), tunedN.CPoint( curIndexN ) );
 }
 else
 {
 m_result.AddCorner( tunedP.CPoint( curIndexP ), tunedN.CPoint( curIndexN ) );
 }
 
 curIndexP = tunedP.NextShape( curIndexP );
 }
 
 while( sp.indexN >= curIndexN && curIndexN != -1 )
 {
 if( tunedN.IsArcSegment( curIndexN ) )
 {
 ssize_t arcIndex = tunedN.ArcIndex( curIndexN );
 
 m_result.AddPtAndArc( tunedP.CPoint( sp.indexP ), tunedN.Arc( arcIndex ) );
 }
 else
 {
 m_result.AddCorner( tunedP.CPoint( sp.indexP ), tunedN.CPoint( curIndexN ) );
 }
 
 curIndexN = tunedN.NextShape( curIndexN );
 }
 
 m_result.MeanderSegment( base, side );
 }
 
 while( curIndexP < tunedP.PointCount() && curIndexP != -1 )
 {
 if( tunedP.IsArcSegment( curIndexP ) )
 {
 ssize_t arcIndex = tunedP.ArcIndex( curIndexP );
 
 m_result.AddArcAndPt( tunedP.Arc( arcIndex ), tunedN.CPoint( curIndexN ) );
 }
 else
 {
 m_result.AddCorner( tunedP.CPoint( curIndexP ), tunedN.CPoint( curIndexN ) );
 }
 
 curIndexP = tunedP.NextShape( curIndexP );
 }
 
 while( curIndexN < tunedN.PointCount() && curIndexN != -1 )
 {
 if( tunedN.IsArcSegment( curIndexN ) )
 {
 ssize_t arcIndex = tunedN.ArcIndex( curIndexN );
 
 m_result.AddPtAndArc( tunedP.CPoint( -1 ), tunedN.Arc( arcIndex ) );
 }
 else
 {
 m_result.AddCorner( tunedP.CPoint( -1 ), tunedN.CPoint( curIndexN ) );
 }
 
 curIndexN = tunedN.NextShape( curIndexN );
 }
 
 long long int dpLen = origPathLength();
 
 m_lastStatus = TUNED;
 
 if( dpLen > m_settings.m_targetLength.Max() )
 {
 m_lastStatus = TOO_LONG;
 m_lastLength = dpLen;
 }
 else
 {
 m_lastLength = dpLen - std::max( tunedP.Length(), tunedN.Length() );
 tuneLineLength( m_result, m_settings.m_targetLength.Opt() - dpLen );
 }
 
 if( m_lastStatus != TOO_LONG )
 {
 tunedP.Clear();
 tunedN.Clear();
 
 for( MEANDER_SHAPE* m : m_result.Meanders() )
 {
 if( m->Type() != MT_EMPTY )
 {
 tunedP.Append( m->CLine( 0 ) );
 tunedN.Append( m->CLine( 1 ) );
 }
 }
 
 m_lastLength += std::max( tunedP.Length(), tunedN.Length() );
 updateStatus();
 }
 
 m_finalShapeP.Clear();
 m_finalShapeN.Clear();
 
 if( m_settings.m_keepEndpoints )
 {
 preP.Simplify();
 tunedP.Simplify();
 postP.Simplify();
 
 m_finalShapeP.Append( preP );
 m_finalShapeP.Append( tunedP );
 m_finalShapeP.Append( postP );
 
 preN.Simplify();
 tunedN.Simplify();
 postN.Simplify();
 
 m_finalShapeN.Append( preN );
 m_finalShapeN.Append( tunedN );
 m_finalShapeN.Append( postN );
 }
 else
 {
 m_finalShapeP.Append( preP );
 m_finalShapeP.Append( tunedP );
 m_finalShapeP.Append( postP );
 m_finalShapeP.Simplify();
 
 m_finalShapeN.Append( preN );
 m_finalShapeN.Append( tunedN );
 m_finalShapeN.Append( postN );
 m_finalShapeN.Simplify();
 }
 
 return true;
}
 
 
bool DP_MEANDER_PLACER::FixRoute( const VECTOR2I& aP, ITEM* aEndItem, bool aForceFinish )
{
 LINE lP( m_originPair.PLine(), m_finalShapeP );
 LINE lN( m_originPair.NLine(), m_finalShapeN );
 
 m_currentNode->Add( lP );
 m_currentNode->Add( lN );
 
 CommitPlacement();
 
 return true;
}
 
 
bool DP_MEANDER_PLACER::AbortPlacement()
{
 m_world->KillChildren();
 return true;
}
 
 
bool DP_MEANDER_PLACER::HasPlacedAnything() const
{
 return m_originPair.CP().SegmentCount() > 0 || m_originPair.CN().SegmentCount() > 0;
}
 
 
bool DP_MEANDER_PLACER::CommitPlacement()
{
 if( m_currentNode )
 Router()->CommitRouting( m_currentNode );
 
 m_currentNode = nullptr;
 return true;
}
 
 
bool DP_MEANDER_PLACER::CheckFit( MEANDER_SHAPE* aShape )
{
 LINE l1( m_originPair.PLine(), aShape->CLine( 0 ) );
 LINE l2( m_originPair.NLine(), aShape->CLine( 1 ) );
 
 if( m_currentNode->CheckColliding( &l1 ) )
 return false;
 
 if( m_currentNode->CheckColliding( &l2 ) )
 return false;
 
 int w = aShape->Width();
 int clearance = w + m_settings.m_spacing;
 
 return m_result.CheckSelfIntersections( aShape, clearance );
}
 
 
const ITEM_SET DP_MEANDER_PLACER::Traces()
{
 m_currentTraceP = LINE( m_originPair.PLine(), m_finalShapeP );
 m_currentTraceN = LINE( m_originPair.NLine(), m_finalShapeN );
 
 ITEM_SET traces;
 
 traces.Add( &m_currentTraceP );
 traces.Add( &m_currentTraceN );
 
 return traces;
}
 
 
const ITEM_SET DP_MEANDER_PLACER::TunedPath()
{
 ITEM_SET lines;
 
 for( ITEM* item : m_tunedPathN )
 lines.Add( item );
 
 for( ITEM* item : m_tunedPathP )
 lines.Add( item );
 
 return lines;
}
 
 
const VECTOR2I& DP_MEANDER_PLACER::CurrentStart() const
{
 return m_currentStart;
}
 
 
const VECTOR2I& DP_MEANDER_PLACER::CurrentEnd() const
{
 return m_currentEnd;
}
 
 
int DP_MEANDER_PLACER::CurrentLayer() const
{
 return m_initialSegment->Layers().Start();
}
 
 
long long int DP_MEANDER_PLACER::TuningResult() const
{
 if( m_lastLength )
 return m_lastLength;
 else
 return origPathLength();
}
 
 
DP_MEANDER_PLACER::TUNING_STATUS DP_MEANDER_PLACER::TuningStatus() const
{
 return m_lastStatus;
}
 
 
const std::vector<NET_HANDLE> DP_MEANDER_PLACER::CurrentNets() const
{
 std::vector<NET_HANDLE> rv;
 rv.push_back( m_originPair.NetP() );
 rv.push_back( m_originPair.NetN() );
 return rv;
}
 
}