PNS_WALKAROUND::WalkaroundStatus PNS_WALKAROUND::singleStep( PNS_LINE& aPath,
bool aWindingDirection )
{
optional<PNS_OBSTACLE>& current_obs =
aWindingDirection ? m_currentObstacle[0] : m_currentObstacle[1];
bool& prev_recursive = aWindingDirection ? m_recursiveCollision[0] : m_recursiveCollision[1];
if( !current_obs )
return DONE;
SHAPE_LINE_CHAIN path_pre[2], path_walk[2], path_post[2];
VECTOR2I last = aPath.GetCLine().CPoint( -1 );
if( ( current_obs->hull ).PointInside( last ) )
{
m_recursiveBlockageCount++;
if( m_recursiveBlockageCount < 3 )
aPath.GetLine().Append( current_obs->hull.NearestPoint( last ) );
else
{
aPath = aPath.ClipToNearestObstacle( m_world );
return STUCK;
}
}
aPath.NewWalkaround( current_obs->hull, path_pre[0], path_walk[0],
path_post[0], aWindingDirection );
aPath.NewWalkaround( current_obs->hull, path_pre[1], path_walk[1],
path_post[1], !aWindingDirection );
int len_pre = path_walk[0].Length();
int len_alt = path_walk[1].Length();
PNS_LINE walk_path( aPath, path_walk[1] );
bool alt_collides = m_world->CheckColliding( &walk_path,
m_solids_only ? PNS_ITEM::SOLID : PNS_ITEM::ANY );
SHAPE_LINE_CHAIN pnew;
if( !m_forceSingleDirection && len_alt < len_pre && !alt_collides && !prev_recursive )
{
pnew = path_pre[1];
pnew.Append( path_walk[1] );
pnew.Append( path_post[1] );
current_obs = nearestObstacle( PNS_LINE( aPath, path_post[1] ) );
prev_recursive = false;
}
else
{
pnew = path_pre[0];
pnew.Append( path_walk[0] );
pnew.Append( path_post[0] );
current_obs = nearestObstacle( PNS_LINE( aPath, path_walk[0] ) );
if( !current_obs )
{
prev_recursive = false;
current_obs = nearestObstacle( PNS_LINE( aPath, path_post[0] ) );
}
else
prev_recursive = true;
}
pnew.Simplify();
aPath.SetShape( pnew );
return IN_PROGRESS;
}
PNS_WALKAROUND::WalkaroundStatus PNS_WALKAROUND::Route( const PNS_LINE& aInitialPath,
PNS_LINE& aWalkPath,
bool aOptimize )
{
PNS_LINE path_cw( aInitialPath ), path_ccw( aInitialPath );
WalkaroundStatus s_cw = IN_PROGRESS, s_ccw = IN_PROGRESS;
SHAPE_LINE_CHAIN best_path;
start( aInitialPath );
m_currentObstacle[0] = m_currentObstacle[1] = nearestObstacle( aInitialPath );
m_recursiveBlockageCount = 0;
aWalkPath = aInitialPath;
while( m_iteration < m_iteration_limit )
{
if( s_cw != STUCK )
s_cw = singleStep( path_cw, true );
if( s_ccw != STUCK )
s_ccw = singleStep( path_ccw, false );
if( ( s_cw == DONE && s_ccw == DONE ) || ( s_cw == STUCK && s_ccw == STUCK ) )
{
int len_cw = path_cw.GetCLine().Length();
int len_ccw = path_ccw.GetCLine().Length();
if( m_forceLongerPath )
aWalkPath = (len_cw > len_ccw ? path_cw : path_ccw);
else
aWalkPath = (len_cw < len_ccw ? path_cw : path_ccw);
break;
}
else if( s_cw == DONE && !m_forceLongerPath )
{
aWalkPath = path_cw;
break;
}
else if( s_ccw == DONE && !m_forceLongerPath )
{
aWalkPath = path_ccw;
break;
}
m_iteration++;
}
if( m_iteration == m_iteration_limit )
{
int len_cw = path_cw.GetCLine().Length();
int len_ccw = path_ccw.GetCLine().Length();
if( m_forceLongerPath )
aWalkPath = (len_cw > len_ccw ? path_cw : path_ccw);
else
aWalkPath = (len_cw < len_ccw ? path_cw : path_ccw);
}
if( m_cursorApproachMode )
{
// int len_cw = path_cw.GetCLine().Length();
// int len_ccw = path_ccw.GetCLine().Length();
bool found = false;
SHAPE_LINE_CHAIN l = aWalkPath.GetCLine();
for( int i = 0; i < l.SegmentCount(); i++ )
{
const SEG s = l.Segment( i );
VECTOR2I nearest = s.NearestPoint( m_cursorPos );
VECTOR2I::extended_type dist_a = ( s.A - m_cursorPos ).SquaredEuclideanNorm();
VECTOR2I::extended_type dist_b = ( s.B - m_cursorPos ).SquaredEuclideanNorm();
VECTOR2I::extended_type dist_n = ( nearest - m_cursorPos ).SquaredEuclideanNorm();
if( dist_n <= dist_a && dist_n < dist_b )
{
// PNSDisplayDebugLine( l, 3 );
l.Remove( i + 1, -1 );
l.Append( nearest );
l.Simplify();
found = true;
break;
}
}
if( found )
{
aWalkPath = aInitialPath;
aWalkPath.SetShape( l );
}
}
aWalkPath.SetWorld( m_world );
aWalkPath.GetLine().Simplify();
WalkaroundStatus st = s_ccw == DONE || s_cw == DONE ? DONE : STUCK;
if( aOptimize && st == DONE )
PNS_OPTIMIZER::Optimize( &aWalkPath, PNS_OPTIMIZER::MERGE_OBTUSE, m_world );
return st;
}
