kicad/pcbnew/router/pns_meander_placer_base.cpp

381 lines
10 KiB
C++

/*
* KiRouter - a push-and-(sometimes-)shove PCB router
*
* Copyright (C) 2013-2015 CERN
* Copyright (C) 2016-2022 KiCad Developers, see AUTHORS.txt for contributors.
* Author: Tomasz Wlostowski <tomasz.wlostowski@cern.ch>
*
* 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 "pns_meander_placer_base.h"
#include "pns_meander.h"
#include "pns_router.h"
#include "pns_solid.h"
#include "pns_arc.h"
namespace PNS {
const int LENGTH_TARGET_TOLERANCE = 20;
MEANDER_PLACER_BASE::MEANDER_PLACER_BASE( ROUTER* aRouter ) :
PLACEMENT_ALGO( aRouter )
{
m_world = nullptr;
m_currentWidth = 0;
m_startPad_n = nullptr;
m_startPad_p = nullptr;
m_endPad_n = nullptr;
m_endPad_p = nullptr;
}
MEANDER_PLACER_BASE::~MEANDER_PLACER_BASE()
{
}
void MEANDER_PLACER_BASE::AmplitudeStep( int aSign )
{
int a = m_settings.m_maxAmplitude + aSign * m_settings.m_step;
a = std::max( a, m_settings.m_minAmplitude );
m_settings.m_maxAmplitude = a;
}
void MEANDER_PLACER_BASE::SpacingStep( int aSign )
{
int s = m_settings.m_spacing + aSign * m_settings.m_step;
s = std::max( s, m_currentWidth + Clearance() );
m_settings.m_spacing = s;
}
int MEANDER_PLACER_BASE::Clearance()
{
// Assumption: All tracks are part of the same net class.
// It shouldn't matter which track we pick. They should all have the same clearance if
// they are part of the same net class. Therefore, pick the first one on the list.
ITEM* itemToCheck = Traces().CItems().front();
PNS::CONSTRAINT constraint;
Router()->GetRuleResolver()->QueryConstraint( PNS::CONSTRAINT_TYPE::CT_CLEARANCE, itemToCheck,
nullptr, CurrentLayer(), &constraint );
wxCHECK_MSG( constraint.m_Value.HasMin(), m_currentWidth, wxT( "No minimum clearance?" ) );
return constraint.m_Value.Min();
}
void MEANDER_PLACER_BASE::UpdateSettings( const MEANDER_SETTINGS& aSettings )
{
m_settings = aSettings;
}
int findAmplitudeBinarySearch( MEANDER_SHAPE& aCopy, int targetLength, int minAmp, int maxAmp )
{
if( minAmp == maxAmp )
return maxAmp;
aCopy.Resize( minAmp );
int minLen = aCopy.CurrentLength();
aCopy.Resize( maxAmp );
int maxLen = aCopy.CurrentLength();
if( minLen > targetLength )
return 0;
if( maxLen < targetLength )
return 0;
int minError = minLen - targetLength;
int maxError = maxLen - targetLength;
if( std::abs( minError ) < LENGTH_TARGET_TOLERANCE
|| std::abs( maxError ) < LENGTH_TARGET_TOLERANCE )
{
return std::abs( minError ) < std::abs( maxError ) ? minAmp : maxAmp;
}
else
{
int left =
findAmplitudeBinarySearch( aCopy, targetLength, minAmp, ( minAmp + maxAmp ) / 2 );
if( left )
return left;
int right =
findAmplitudeBinarySearch( aCopy, targetLength, ( minAmp + maxAmp ) / 2, maxAmp );
if( right )
return right;
}
return 0;
}
int findAmplitudeForLength( MEANDER_SHAPE* m, int targetLength, int minAmp, int maxAmp )
{
MEANDER_SHAPE copy = *m;
// Try to keep the same baseline length
copy.SetTargetBaselineLength( m->BaselineLength() );
long long initialGuess = m->Amplitude() - ( m->CurrentLength() - targetLength ) / 2;
if( initialGuess >= minAmp && initialGuess <= maxAmp )
{
copy.Resize( minAmp );
if( std::abs( copy.CurrentLength() - targetLength ) < LENGTH_TARGET_TOLERANCE )
return initialGuess;
}
// The length is non-trivial, use binary search
return findAmplitudeBinarySearch( copy, targetLength, minAmp, maxAmp );
}
void MEANDER_PLACER_BASE::tuneLineLength( MEANDERED_LINE& aTuned, long long int aElongation )
{
long long int maxElongation = 0;
long long int minElongation = 0;
bool finished = false;
for( MEANDER_SHAPE* m : aTuned.Meanders() )
{
if( m->Type() != MT_CORNER && m->Type() != MT_ARC )
{
MEANDER_SHAPE end = *m;
MEANDER_TYPE endType;
if( m->Type() == MT_START || m->Type() == MT_SINGLE )
endType = MT_SINGLE;
else
endType = MT_FINISH;
end.SetType( endType );
end.Recalculate();
long long int maxEndElongation = end.CurrentLength() - end.BaselineLength();
if( maxElongation + maxEndElongation > aElongation )
{
if( !finished )
{
m->SetType( endType );
m->Recalculate();
if( endType == MT_SINGLE )
{
// Check if we need to fit this meander
long long int endMinElongation =
( m->MinTunableLength() - m->BaselineLength() );
if( minElongation + endMinElongation >= aElongation )
m->MakeEmpty();
}
finished = true;
}
else
{
m->MakeEmpty();
}
}
maxElongation += m->CurrentLength() - m->BaselineLength();
minElongation += m->MinTunableLength() - m->BaselineLength();
}
}
long long int remainingElongation = aElongation;
int meanderCount = 0;
for( MEANDER_SHAPE* m : aTuned.Meanders() )
{
if( m->Type() != MT_CORNER && m->Type() != MT_ARC && m->Type() != MT_EMPTY )
{
remainingElongation -= m->CurrentLength() - m->BaselineLength();
meanderCount++;
}
}
long long int lenReductionLeft = -remainingElongation;
int meandersLeft = meanderCount;
if( lenReductionLeft < 0 || !meandersLeft )
return;
for( MEANDER_SHAPE* m : aTuned.Meanders() )
{
if( m->Type() != MT_CORNER && m->Type() != MT_ARC && m->Type() != MT_EMPTY )
{
long long int lenReductionHere = lenReductionLeft / meandersLeft;
long long int initialLen = m->CurrentLength();
int minAmpl = m->MinAmplitude();
int amp = findAmplitudeForLength( m, initialLen - lenReductionHere, minAmpl,
m->Amplitude() );
if( amp < minAmpl )
amp = minAmpl;
m->SetTargetBaselineLength( m->BaselineLength() );
m->Resize( amp );
lenReductionLeft -= initialLen - m->CurrentLength();
meandersLeft--;
if( !meandersLeft )
break;
}
}
}
int MEANDER_PLACER_BASE::GetTotalPadToDieLength( const LINE& aLine ) const
{
int length = 0;
JOINT start;
JOINT end;
m_world->FindLineEnds( aLine, start, end );
// Extract the length of the pad to die for start and end pads
for( auto& link : start.LinkList() )
{
if( const SOLID* solid = dyn_cast<const SOLID*>( link ) )
{
// If there are overlapping pads, choose the first with a non-zero length
if( solid->GetPadToDie() > 0 )
{
length += solid->GetPadToDie();
break;
}
}
}
for( auto& link : end.LinkList() )
{
if( const SOLID* solid = dyn_cast<const SOLID*>( link ) )
{
if( solid->GetPadToDie() > 0 )
{
length += solid->GetPadToDie();
break;
}
}
}
return length;
}
const MEANDER_SETTINGS& MEANDER_PLACER_BASE::MeanderSettings() const
{
return m_settings;
}
VECTOR2I MEANDER_PLACER_BASE::getSnappedStartPoint( LINKED_ITEM* aStartItem, VECTOR2I aStartPoint )
{
if( aStartItem->Kind() == ITEM::SEGMENT_T )
{
return static_cast<SEGMENT*>( aStartItem )->Seg().NearestPoint( aStartPoint );
}
else
{
wxASSERT( aStartItem->Kind() == ITEM::ARC_T );
ARC* arc = static_cast<ARC*>( aStartItem );
if( ( VECTOR2I( arc->Anchor( 0 ) - aStartPoint ) ).SquaredEuclideanNorm() <=
( VECTOR2I( arc->Anchor( 1 ) - aStartPoint ) ).SquaredEuclideanNorm() )
{
return arc->Anchor( 0 );
}
else
{
return arc->Anchor( 1 );
}
}
}
long long int MEANDER_PLACER_BASE::lineLength( const ITEM_SET& aLine, const SOLID* aStartPad, const SOLID* aEndPad ) const
{
long long int total = 0;
if( aLine.Empty() )
return 0;
const ITEM* start_item = aLine[0];
const ITEM* end_item = aLine[aLine.Size() - 1];
bool start_via = false;
bool end_via = false;
/**
* If there is a start pad but the pad's layers do not overlap the first track layer, then there must be a
* fanout via on the line. If there isn't, we still need to have the via back to the pad, so count the distance
* in the line tuning
*/
start_via = aStartPad && ( !aStartPad->LayersOverlap( start_item ) );
end_via = aEndPad && ( !aEndPad->LayersOverlap( end_item ) );
for( int idx = 0; idx < aLine.Size(); idx++ )
{
const ITEM* item = aLine[idx];
if( const LINE* l = dyn_cast<const LINE*>( item ) )
{
total += l->CLine().Length();
}
else if( item->OfKind( ITEM::VIA_T ) && idx > 0 && idx < aLine.Size() - 1 )
{
int layerPrev = aLine[idx - 1]->Layer();
int layerNext = aLine[idx + 1]->Layer();
if( layerPrev != layerNext )
total += m_router->GetInterface()->StackupHeight( layerPrev, layerNext );
}
}
if( start_via )
{
int layerPrev = aStartPad->Layer();
int layerNext = start_item->Layer();
total += m_router->GetInterface()->StackupHeight( layerPrev, layerNext );
}
if( end_via )
{
int layerPrev = end_item->Layer();
int layerNext = aEndPad->Layer();
total += m_router->GetInterface()->StackupHeight( layerPrev, layerNext );
}
return total;
}
}