Merge pull request #4 from FOSSEE/develop

merging dev into master

1 files changed, 158 insertions, 0 deletions

diff --git a/common/geometry/seg.cpp b/common/geometry/seg.cpp
new file mode 100644
index 0000000..f1796b6
--- /dev/null
+++ b/common/geometry/seg.cpp
@@ -0,0 +1,158 @@
+/*
+ * This program source code file is part of KiCad, a free EDA CAD application.
+ *
+ * Copyright (C) 2013 CERN
+ * @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 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 <geometry/seg.h>
+
+template <typename T>
+int sgn( T aVal )
+{
+    return ( T( 0 ) < aVal ) - ( aVal < T( 0 ) );
+}
+
+
+bool SEG::PointCloserThan( const VECTOR2I& aP, int aDist ) const
+{
+    VECTOR2I d = B - A;
+    ecoord dist_sq = (ecoord) aDist * aDist;
+
+    SEG::ecoord l_squared = d.Dot( d );
+    SEG::ecoord t = d.Dot( aP - A );
+
+    if( t <= 0 || !l_squared )
+        return ( aP - A ).SquaredEuclideanNorm() < dist_sq;
+    else if( t >= l_squared )
+        return ( aP - B ).SquaredEuclideanNorm() < dist_sq;
+
+    int dxdy = abs( d.x ) - abs( d.y );
+
+    if( ( dxdy >= -1 && dxdy <= 1 ) || abs( d.x ) <= 1 || abs( d.y ) <= 1 )
+    {
+        int ca = -sgn( d.y );
+        int cb = sgn( d.x );
+        int cc = -ca * A.x - cb * A.y;
+
+        ecoord num = (ecoord) ca * aP.x + (ecoord) cb * aP.y + cc;
+        num *= num;
+
+        if( ca && cb )
+            num >>= 1;
+
+        if( num > ( dist_sq + 100 ) )
+            return false;
+
+        else if( num < ( dist_sq - 100 ) )
+            return true;
+    }
+
+    VECTOR2I nearest;
+    nearest.x = A.x + rescale( t, (ecoord) d.x, l_squared );
+    nearest.y = A.y + rescale( t, (ecoord) d.y, l_squared );
+
+    return ( nearest - aP ).SquaredEuclideanNorm() <= dist_sq;
+}
+
+
+SEG::ecoord SEG::SquaredDistance( const SEG& aSeg ) const
+{
+    // fixme: rather inefficient....
+    if( Intersect( aSeg ) )
+        return 0;
+
+    const VECTOR2I pts[4] =
+    {
+        aSeg.NearestPoint( A ) - A,
+        aSeg.NearestPoint( B ) - B,
+        NearestPoint( aSeg.A ) - aSeg.A,
+        NearestPoint( aSeg.B ) - aSeg.B
+    };
+
+    ecoord m = VECTOR2I::ECOORD_MAX;
+
+    for( int i = 0; i < 4; i++ )
+        m = std::min( m, pts[i].SquaredEuclideanNorm() );
+
+    return m;
+}
+
+
+OPT_VECTOR2I SEG::Intersect( const SEG& aSeg, bool aIgnoreEndpoints, bool aLines ) const
+{
+    const VECTOR2I  e( B - A );
+    const VECTOR2I  f( aSeg.B - aSeg.A );
+    const VECTOR2I  ac( aSeg.A - A );
+
+    ecoord d = f.Cross( e );
+    ecoord p = f.Cross( ac );
+    ecoord q = e.Cross( ac );
+
+    if( d == 0 )
+        return OPT_VECTOR2I();
+
+    if( !aLines && d > 0 && ( q < 0 || q > d || p < 0 || p > d ) )
+        return OPT_VECTOR2I();
+
+    if( !aLines && d < 0 && ( q < d || p < d || p > 0 || q > 0 ) )
+        return OPT_VECTOR2I();
+
+    if( !aLines && aIgnoreEndpoints && ( q == 0 || q == d ) && ( p == 0 || p == d ) )
+        return OPT_VECTOR2I();
+
+    VECTOR2I ip( aSeg.A.x + rescale( q, (ecoord) f.x, d ),
+                 aSeg.A.y + rescale( q, (ecoord) f.y, d ) );
+
+     return ip;
+}
+
+
+bool SEG::ccw( const VECTOR2I& aA, const VECTOR2I& aB, const VECTOR2I& aC ) const
+{
+    return (ecoord) ( aC.y - aA.y ) * ( aB.x - aA.x ) > (ecoord) ( aB.y - aA.y ) * ( aC.x - aA.x );
+}
+
+
+bool SEG::Collide( const SEG& aSeg, int aClearance ) const
+{
+    // check for intersection
+    // fixme: move to a method
+    if( ccw( A, aSeg.A, aSeg.B ) != ccw( B, aSeg.A, aSeg.B ) &&
+            ccw( A, B, aSeg.A ) != ccw( A, B, aSeg.B ) )
+        return true;
+
+#define CHK( _seg, _pt ) \
+    if( (_seg).PointCloserThan( _pt, aClearance ) ) return true;
+
+    CHK( *this, aSeg.A );
+    CHK( *this, aSeg.B );
+    CHK( aSeg, A );
+    CHK( aSeg, B );
+#undef CHK
+
+    return false;
+}
+
+
+bool SEG::Contains( const VECTOR2I& aP ) const
+{
+    return PointCloserThan( aP, 1 );
+}