pns_item.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 "pns_node.h"
#include "pns_item.h"
#include "pns_line.h"
#include "pns_router.h"
 
#include <geometry/shape_compound.h>
#include <geometry/shape_poly_set.h>
 
typedef VECTOR2I::extended_type ecoord;
 
namespace PNS {
 
static void dumpObstacles( const PNS::NODE::OBSTACLES &obstacles )
{
 printf( "&&&& %zu obstacles: \n", obstacles.size() );
 
 for( const auto& obs : obstacles )
 {
 printf( "%p [%s] - %p [%s], clearance %d\n",
 obs.m_head, obs.m_head->KindStr().c_str(),
 obs.m_item, obs.m_item->KindStr().c_str(),
 obs.m_clearance );
 }
}
 
 
// prune self-collisions, i.e. a via/pad annular ring with its own hole
static bool shouldWeConsiderHoleCollisions( const ITEM* aItem, const ITEM* aHead )
{
 const HOLE* holeI = aItem->OfKind( ITEM::HOLE_T ) ? static_cast<const HOLE*>( aItem ) : nullptr;
 const HOLE* holeH = aHead->OfKind( ITEM::HOLE_T ) ? static_cast<const HOLE*>( aHead ) : nullptr;
 
 if( holeI && holeH ) // hole-to-hole case
 {
 const ITEM* parentI = holeI->ParentPadVia();
 const ITEM* parentH = holeH->ParentPadVia();
 if( !parentH || !parentI )
 return true;
 
 const VIA* parentViaI = dyn_cast<const VIA*>( parentI );
 const VIA* parentViaH = dyn_cast<const VIA*>( parentH );
 
 // Note to self: the if() below is an ugly heuristic to determine if we aren't trying
 // to check for collisions of the hole of the via with another (although identical)
 // copy of it. Such case occurs when checking a LINE against a NODE where this LINE
 // has been already added. LINE has no notion of ownership of it's via (it's just a
 // copy) and before hole-to-hole clearance support has been introduced it didn't matter
 // becasue we didn't consider collisions of the objects belonging to the same net anyway
 // Now that hole clearance check doesn't care about the nets assigned to the parent
 // vias/solids, I'll probably have to refactor the LINE class to manage ownership of
 // its (optional) VIA. For the moment, we just treat via holes that are geometrically
 // identical and belonging to the same net as non-colliding.
 
 if( parentViaI && parentViaH && parentViaI->Pos() == parentViaH->Pos()
 && parentViaI->Diameter() == parentViaH->Diameter()
 && parentViaI->Net() == parentViaH->Net()
 && parentViaI->Drill() == parentViaH->Drill() )
 return false;
 
 return parentI != parentH;
 }
 
 if( holeI )
 return holeI->ParentPadVia() != aHead;
 else if( holeH )
 return holeH->ParentPadVia() != aItem;
 else
 return true;
}
 
 
bool ITEM::collideSimple( const ITEM* aHead, const NODE* aNode,
 COLLISION_SEARCH_CONTEXT* aCtx ) const
{
 // Note: if 'this' is a pad or a via then its hole is a separate PNS::ITEM in the node's
 // index and we don't need to deal with holeI here. The same is *not* true of the routing
 // "head", so we do need to handle holeH.
 
 const SHAPE* shapeI = Shape();
 int lineWidthI = 0;
 
 const SHAPE* shapeH = aHead->Shape();
 const HOLE* holeH = aHead->Hole();
 int lineWidthH = 0;
 int clearanceEpsilon = aNode->GetRuleResolver()->ClearanceEpsilon();
 bool collisionsFound = false;
 
 if( this == aHead ) // we cannot be self-colliding
 return false;
 
 if ( !shouldWeConsiderHoleCollisions( this, aHead ) )
 return false;
 
 // Special cases for "head" lines with vias attached at the end. Note that this does not
 // support head-line-via to head-line-via collisions, but you can't route two independent
 // tracks at once so it shouldn't come up.
 
 if( const auto line = dyn_cast<const LINE*>( this ) )
 {
 if( line->EndsWithVia() )
 collisionsFound |= line->Via().collideSimple( aHead, aNode, aCtx );
 }
 
 if( const auto line = dyn_cast<const LINE*>( aHead ) )
 {
 if( line->EndsWithVia() )
 collisionsFound |= line->Via().collideSimple( this, aNode, aCtx );
 }
 
 // And a special case for the "head" via's hole.
 if( holeH && shouldWeConsiderHoleCollisions( this, holeH ) )
 {
 if( collideSimple( holeH, aNode, aCtx ) )
 collisionsFound = true;
 }
 
 // Sadly collision routines ignore SHAPE_POLY_LINE widths so we have to pass them in as part
 // of the clearance value.
 if( m_kind == LINE_T )
 lineWidthI = static_cast<const LINE*>( this )->Width() / 2;
 
 if( aHead->m_kind == LINE_T )
 lineWidthH = static_cast<const LINE*>( aHead )->Width() / 2;
 
 // check if we are not on completely different layers first
 if( !m_layers.Overlaps( aHead->m_layers ) )
 return false;
 
 // fixme: this f***ing singleton must go...
 ROUTER* router = ROUTER::GetInstance();
 ROUTER_IFACE* iface = router ? router->GetInterface() : nullptr;
 bool differentNetsOnly = true;
 bool enforce = false;
 int clearance;
 
 if( aCtx )
 differentNetsOnly = aCtx->options.m_differentNetsOnly;
 
 // Hole-to-hole collisions don't have anything to do with nets
 if( Kind() == HOLE_T && aHead->Kind() == HOLE_T )
 differentNetsOnly = false;
 
 if( differentNetsOnly && Net() == aHead->Net() && aHead->Net() )
 {
 // same nets? no clearance!
 clearance = -1;
 }
 else if( differentNetsOnly && ( IsFreePad() || aHead->IsFreePad() ) )
 {
 // a pad associated with a "free" pin (NIC) doesn't have a net until it has been used
 clearance = -1;
 }
 else if( aNode->GetRuleResolver()->IsKeepout( this, aHead, &enforce ) )
 {
 if( enforce )
 clearance = 0; // keepouts are exact boundary; no clearance
 else
 clearance = -1;
 }
 else if( iface && !iface->IsFlashedOnLayer( this, aHead->Layers() ) )
 {
 clearance = -1;
 }
 else if( iface && !iface->IsFlashedOnLayer( aHead, Layers() ) )
 {
 clearance = -1;
 }
 else if( aCtx && aCtx->options.m_overrideClearance >= 0 )
 {
 clearance = aCtx->options.m_overrideClearance;
 }
 else
 {
 clearance = aNode->GetClearance( this, aHead, aCtx ? aCtx->options.m_useClearanceEpsilon
 : false );
 }
 
 if( clearance >= 0 )
 {
 // Note: we can't do castellation or net-tie processing in GetClearance() because they
 // depend on *where* the collision is.
 
 bool checkCastellation = ( m_parent && m_parent->GetLayer() == Edge_Cuts );
 bool checkNetTie = ( m_parent && aNode->GetRuleResolver()->IsInNetTie( this ) );
 
 if( checkCastellation || checkNetTie )
 {
 // Slow method
 int actual;
 VECTOR2I pos;
 
 if( shapeH->Collide( shapeI, clearance + lineWidthH + lineWidthI - clearanceEpsilon,
 &actual, &pos ) )
 {
 if( checkCastellation && aNode->QueryEdgeExclusions( pos ) )
 return false;
 
 if( checkNetTie && aNode->GetRuleResolver()->IsNetTieExclusion( aHead, pos, this ) )
 return false;
 
 if( aCtx )
 {
 collisionsFound = true;
 OBSTACLE obs;
 obs.m_head = const_cast<ITEM*>( aHead );
 obs.m_item = const_cast<ITEM*>( this );
 obs.m_clearance = clearance;
 obs.m_distFirst = 0;
 obs.m_maxFanoutWidth = 0;
 aCtx->obstacles.insert( obs );
 }
 else
 {
 return true;
 }
 }
 }
 else
 {
 // Fast method
 if( shapeH->Collide( shapeI, clearance + lineWidthH + lineWidthI - clearanceEpsilon ) )
 {
 if( aCtx )
 {
 collisionsFound = true;
 OBSTACLE obs;
 obs.m_head = const_cast<ITEM*>( aHead );
 obs.m_item = const_cast<ITEM*>( this );
 obs.m_clearance = clearance;
 obs.m_distFirst = 0;
 obs.m_maxFanoutWidth = 0;
 obs.m_violatingConstraint = CONSTRAINT_TYPE::CT_CLEARANCE;
 aCtx->obstacles.insert( obs );
 }
 else
 {
 return true;
 }
 }
 }
 }
 
 return collisionsFound;
}
 
 
bool ITEM::Collide( const ITEM* aOther, const NODE* aNode, COLLISION_SEARCH_CONTEXT *aCtx ) const
{
 if( collideSimple( aOther, aNode, aCtx ) )
 return true;
 
 return false;
}
 
 
std::string ITEM::KindStr() const
{
 switch( m_kind )
 {
 case ARC_T: return "arc";
 case LINE_T: return "line";
 case SEGMENT_T: return "segment";
 case VIA_T: return "via";
 case JOINT_T: return "joint";
 case SOLID_T: return "solid";
 case DIFF_PAIR_T: return "diff-pair";
 case HOLE_T: return "hole";
 
 default: return "unknown";
 }
}
 
 
ITEM::~ITEM()
{
}
 
 
const std::string ITEM::Format() const
{
 ROUTER* router = ROUTER::GetInstance();
 ROUTER_IFACE* iface = router ? router->GetInterface() : nullptr;
 
 std::stringstream ss;
 ss << KindStr() << " ";
 
 if( iface )
 ss << "net " << iface->GetNetCode( Net() ) << " ";
 
 ss << "layers " << m_layers.Start() << " " << m_layers.End();
 return ss.str();
}
 
 
const NODE* ITEM::OwningNode() const
{
 if( ParentPadVia() )
 return static_cast<const NODE*>( ParentPadVia()->Owner() );
 else
 return static_cast<const NODE*>( Owner() );
}
 
} // namespace PNS