src/operation/overlay/snap/SnapOverlayOp.cpp

   1 /**********************************************************************
   2  *
   3  * GEOS - Geometry Engine Open Source
   4  * http://geos.osgeo.org
   5  *
   6  * Copyright (C) 2009  Sandro Santilli <strk@keybit.net>
   7  *
   8  * This is free software; you can redistribute and/or modify it under
   9  * the terms of the GNU Lesser General Public Licence as published
  10  * by the Free Software Foundation.
  11  * See the COPYING file for more information.
  12  *
  13  ***********************************************************************
  14  *
  15  * Last port: operation/overlay/snap/SnapOverlayOp.java r320 (JTS-1.12)
  16  *
  17  **********************************************************************/
  18
  19 #include <geos/operation/overlay/snap/SnapOverlayOp.h>
  20 #include <geos/operation/overlay/snap/GeometrySnapper.h>
  21 #include <geos/precision/CommonBitsRemover.h>
  22 #include <geos/geom/Geometry.h>
  23
  24 #include <cassert>
  25 #include <limits> // for numeric_limits
  26 #include <memory> // for auto_ptr
  27
  28 #ifndef GEOS_DEBUG
  29 #define GEOS_DEBUG 0
  30 #endif
  31
  32 using namespace std;
  33 using namespace geos::geom;
  34
  35 namespace geos {
  36 namespace operation { // geos.operation
  37 namespace overlay { // geos.operation.overlay
  38 namespace snap { // geos.operation.overlay.snap
  39
  40 /* private */
  41 void
  42 SnapOverlayOp::computeSnapTolerance()
  43 {
  44         snapTolerance = GeometrySnapper::computeOverlaySnapTolerance(geom0,
  45                                                                      geom1);
  46
  47         // cout << "Snap tol = " <<  snapTolerance << endl;
  48 }
  49
  50 /* public */
  51 auto_ptr<Geometry>
  52 SnapOverlayOp::getResultGeometry(OverlayOp::OpCode opCode)
  53 {
  54         geom::GeomPtrPair prepGeom;
  55         snap(prepGeom);
  56         GeomPtr result ( OverlayOp::overlayOp(prepGeom.first.get(),
  57                                               prepGeom.second.get(), opCode) );
  58         prepareResult(*result);
  59         return result;
  60 }
  61
  62 /* private */
  63 void
  64 SnapOverlayOp::snap(geom::GeomPtrPair& snapGeom)
  65 {
  66         geom::GeomPtrPair remGeom;
  67         removeCommonBits(geom0, geom1, remGeom);
  68
  69         GeometrySnapper::snap(*remGeom.first, *remGeom.second,
  70                               snapTolerance, snapGeom);
  71
  72     // MD - may want to do this at some point, but it adds cycles
  73 //    checkValid(snapGeom[0]);
  74 //    checkValid(snapGeom[1]);
  75
  76     /*
  77     System.out.println("Snapped geoms: ");
  78     System.out.println(snapGeom[0]);
  79     System.out.println(snapGeom[1]);
  80     */
  81
  82 }
  83
  84 /* private */
  85 void
  86 SnapOverlayOp::removeCommonBits(const geom::Geometry& geom0,
  87                                 const geom::Geometry& geom1,
  88                                 geom::GeomPtrPair& remGeom)
  89 {
  90         cbr.reset(new precision::CommonBitsRemover());
  91         cbr->add(&geom0);
  92         cbr->add(&geom1);
  93
  94         remGeom.first.reset( cbr->removeCommonBits(geom0.clone()) );
  95         remGeom.second.reset( cbr->removeCommonBits(geom1.clone()) );
  96 }
  97
  98 /*private*/
  99 void
 100 SnapOverlayOp::prepareResult(geom::Geometry& geom)
 101 {
 102     cbr->addCommonBits(&geom);
 103 }
 104
 105
 106 } // namespace geos.operation.snap
 107 } // namespace geos.operation.overlay
 108 } // namespace geos.operation
 109 } // namespace geos
 110