Use spatial index to check shell nesting in IsValidOp

include/geos/algorithm/locate/IndexedPointInAreaLocator.h

@@ -104,6 +104,10 @@ class IndexedPointInAreaLocator : public PointOnGeometryLocator {
      */
     IndexedPointInAreaLocator(const geom::Geometry& g);
 
+    const geom::Geometry&  getGeometry() const {
+        return areaGeom;
+    }
+
     /** \brief
      * Determines the [Location](@ref geom::Location) of a point in an areal
      * [Geometry](@ref geom::Geometry).

include/geos/geomgraph/GeometryGraph.h

@@ -187,7 +187,7 @@ class GEOS_DLL GeometryGraph: public PlanarGraph {
     /// Returned object is owned by this GeometryGraph
     geom::CoordinateSequence* getBoundaryPoints();
 
-    Edge* findEdge(const geom::LineString* line);
+    Edge* findEdge(const geom::LineString* line) const;
 
     void computeSplitEdges(std::vector<Edge*>* edgelist);
 

include/geos/operation/valid/IndexedNestedShellTester.h

@@ -0,0 +1,108 @@
+/**********************************************************************
+ *
+ * GEOS - Geometry Engine Open Source
+ * http://geos.osgeo.org
+ *
+ * Copyright (C) 2001-2002 Vivid Solutions Inc.
+ * Copyright (C) 2005 Refractions Research Inc.
+ * Copyright (C) 2010 Safe Software Inc.
+ * Copyright (C) 2010 Sandro Santilli <[email protected]>
+ * Copyright (C) 2019 Daniel Baston <[email protected]>
+ *
+ * This is free software; you can redistribute and/or modify it under
+ * the terms of the GNU Lesser General Public Licence as published
+ * by the Free Software Foundation.
+ * See the COPYING file for more information.
+ *
+ **********************************************************************/
+
+#ifndef GEOS_OP_VALID_INDEXEDNESTEDSHELLTESTER_H
+#define GEOS_OP_VALID_INDEXEDNESTEDSHELLTESTER_H
+
+#include <geos/geom/Polygon.h>
+#include <geos/index/SpatialIndex.h>
+
+#include <cstddef>
+#include <memory>
+
+// Forward declarations
+namespace geos {
+namespace algorithm {
+namespace locate {
+    class IndexedPointInAreaLocator;
+}
+}
+namespace geom {
+    class Polygon;
+}
+namespace geomgraph {
+    class GeometryGraph;
+}
+namespace operation {
+namespace valid {
+    class PolygonIndexedLocators;
+}
+}
+}
+
+namespace geos {
+namespace operation {
+namespace valid {
+
+class IndexedNestedShellTester {
+
+public:
+    IndexedNestedShellTester(const geomgraph::GeometryGraph& g, size_t initialCapacity);
+
+    void add(const geom::Polygon& p) {
+        polys.push_back(&p);
+    }
+
+    const geom::Coordinate* getNestedPoint();
+
+    bool isNonNested();
+
+private:
+    void compute();
+
+    /**
+     * Check if a shell is incorrectly nested within a polygon.
+     * This is the case if the shell is inside the polygon shell,
+     * but not inside a polygon hole.
+     * (If the shell is inside a polygon hole, the nesting is valid.)
+     *
+     * The algorithm used relies on the fact that the rings must be
+     * properly contained.
+     * E.g. they cannot partially overlap (this has been previously
+     * checked by <code>checkRelateConsistency</code>
+     */
+    void checkShellNotNested(const geom::LinearRing* shell, PolygonIndexedLocators & locs);
+
+    /**
+     * This routine checks to see if a shell is properly contained
+     * in a hole.
+     * It assumes that the edges of the shell and hole do not
+     * properly intersect.
+     *
+     * @return <code>null</code> if the shell is properly contained, or
+     *   a Coordinate which is not inside the hole if it is not
+     */
+    const geom::Coordinate* checkShellInsideHole(const geom::LinearRing* shell,
+            algorithm::locate::IndexedPointInAreaLocator & holeLoc);
+
+    /// Externally owned
+    const geomgraph::GeometryGraph& graph;
+
+    std::vector<const geom::Polygon*> polys;
+
+    // Externally owned, if not null
+    const geom::Coordinate* nestedPt;
+
+    bool processed;
+};
+
+}
+}
+}
+
+#endif //GEOS_INDEXEDNESTEDSHELLTESTER_H

include/geos/operation/valid/IsValidOp.h

@@ -149,35 +149,6 @@ class GEOS_DLL IsValidOp {
     void checkShellsNotNested(const geom::MultiPolygon* mp,
                               geomgraph::GeometryGraph* graph);
 
-    /**
-     * Check if a shell is incorrectly nested within a polygon.
-     * This is the case if the shell is inside the polygon shell,
-     * but not inside a polygon hole.
-     * (If the shell is inside a polygon hole, the nesting is valid.)
-     *
-     * The algorithm used relies on the fact that the rings must be
-     * properly contained.
-     * E.g. they cannot partially overlap (this has been previously
-     * checked by <code>checkRelateConsistency</code>
-     */
-    void checkShellNotNested(const geom::LinearRing* shell,
-                             const geom::Polygon* p,
-                             geomgraph::GeometryGraph* graph);
-
-    /**
-     * This routine checks to see if a shell is properly contained
-     * in a hole.
-     * It assumes that the edges of the shell and hole do not
-     * properly intersect.
-     *
-     * @return <code>null</code> if the shell is properly contained, or
-     *   a Coordinate which is not inside the hole if it is not
-     *
-     */
-    const geom::Coordinate* checkShellInsideHole(
-        const geom::LinearRing* shell,
-        const geom::LinearRing* hole,
-        geomgraph::GeometryGraph* graph);
 
     void checkConnectedInteriors(geomgraph::GeometryGraph& graph);
 
@@ -201,7 +172,7 @@ class GEOS_DLL IsValidOp {
     static const geom::Coordinate* findPtNotNode(
         const geom::CoordinateSequence* testCoords,
         const geom::LinearRing* searchRing,
-        geomgraph::GeometryGraph* graph);
+        const geomgraph::GeometryGraph* graph);
 
     /** \brief
      * Checks whether a coordinate is valid for processing.

include/geos/operation/valid/Makefile.am

@@ -11,6 +11,7 @@ geos_HEADERS = \
     ConnectedInteriorTester.h   \
     ConsistentAreaTester.h      \
     IsValidOp.h                 \
+    IndexedNestedShellTester.h  \
     MakeValid.h                 \
     QuadtreeNestedRingTester.h  \
     RepeatedPointRemover.h      \

src/geomgraph/GeometryGraph.cpp

@@ -147,7 +147,7 @@ GeometryGraph::getBoundaryPoints()
 }
 
 Edge*
-GeometryGraph::findEdge(const LineString* line)
+GeometryGraph::findEdge(const LineString* line) const
 {
     return lineEdgeMap.find(line)->second;
 }

src/operation/valid/IndexedNestedRingTester.h

@@ -19,6 +19,7 @@
 #ifndef GEOS_OP_VALID_OFFSETCURVEVERTEXLIST_H
 #define GEOS_OP_VALID_OFFSETCURVEVERTEXLIST_H
 
+#include <cstddef>
 #include <vector> // for composition
 
 // Forward declarations