/********************************************************************** * * GEOS - Geometry Engine Open Source * http://geos.osgeo.org * * Copyright (C) 2009-2011 Sandro Santilli * Copyright (C) 2008-2010 Safe Software Inc. * Copyright (C) 2006-2007 Refractions Research Inc. * * 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. * ********************************************************************** * * Last port: operation/buffer/BufferBuilder.java 149b38907 (JTS-1.12) * **********************************************************************/ #pragma once #include #include #include // for inlines (BufferOp enums) #include // for inline (OffsetCurveBuilder enums) #include // for composition #ifdef _MSC_VER #pragma warning(push) #pragma warning(disable: 4251) // warning C4251: needs to have dll-interface to be used by clients of class #endif // Forward declarations namespace geos { namespace geom { class PrecisionModel; class Geometry; class GeometryFactory; } namespace algorithm { class LineIntersector; } namespace noding { class Noder; class SegmentString; class IntersectionAdder; } namespace geomgraph { class Edge; class Label; class PlanarGraph; } namespace operation { namespace buffer { class BufferSubgraph; } namespace overlay { class PolygonBuilder; } } } namespace geos { namespace operation { // geos.operation namespace buffer { // geos.operation.buffer /** * * \brief * Builds the buffer geometry for a given input geometry and precision model. * * Allows setting the level of approximation for circular arcs, * and the precision model in which to carry out the computation. * * When computing buffers in floating point double-precision * it can happen that the process of iterated noding can fail to converge * (terminate). * * In this case a TopologyException will be thrown. * Retrying the computation in a fixed precision * can produce more robust results. * */ class GEOS_DLL BufferBuilder { public: /** * Creates a new BufferBuilder * * @param nBufParams buffer parameters, this object will * keep a reference to the passed parameters * so caller must make sure the object is * kept alive for the whole lifetime of * the buffer builder. */ BufferBuilder(const BufferParameters& nBufParams) : bufParams(nBufParams), workingPrecisionModel(nullptr), li(nullptr), intersectionAdder(nullptr), workingNoder(nullptr), geomFact(nullptr), edgeList(), isInvertOrientation(false) {} ~BufferBuilder(); /** * Sets the precision model to use during the curve computation * and noding, * if it is different to the precision model of the Geometry. * If the precision model is less than the precision of the * Geometry precision model, * the Geometry must have previously been rounded to that precision. * * @param pm the precision model to use */ void setWorkingPrecisionModel(const geom::PrecisionModel* pm) { workingPrecisionModel = pm; } /** * Sets the {@link noding::Noder} to use during noding. * This allows choosing fast but non-robust noding, or slower * but robust noding. * * @param newNoder the noder to use */ void setNoder(noding::Noder* newNoder) { workingNoder = newNoder; } /** * Sets whether the offset curve is generated * using the inverted orientation of input rings. * This allows generating a buffer(0) polygon from the smaller lobes * of self-crossing rings. * * @param p_isInvertOrientation true if input ring orientation should be inverted */ void setInvertOrientation(bool p_isInvertOrientation) { isInvertOrientation = p_isInvertOrientation; } std::unique_ptr buffer(const geom::Geometry* g, double distance); /** * Generates offset curve for linear geometry. * * @param g non-areal geometry object * @param distance width of offset * @param leftSide controls on which side of the input geometry * offset curve is generated. * * @note For left-side offset curve, the offset will be at the left side * of the input line and retain the same direction. * For right-side offset curve, it'll be at the right side * and in the opposite direction. * * @note BufferParameters::setSingleSided parameter, which is specific to * areal geometries only, is ignored by this routine. * * @note Not in JTS: this is a GEOS extension */ std::unique_ptr bufferLineSingleSided( const geom::Geometry* g, double distance, bool leftSide); private: /** * Compute the change in depth as an edge is crossed from R to L */ static int depthDelta(const geomgraph::Label& label); const BufferParameters& bufParams; const geom::PrecisionModel* workingPrecisionModel; algorithm::LineIntersector* li; noding::IntersectionAdder* intersectionAdder; noding::Noder* workingNoder; const geom::GeometryFactory* geomFact; geomgraph::EdgeList edgeList; std::vector newLabels; bool isInvertOrientation; void computeNodedEdges(std::vector& bufSegStr, const geom::PrecisionModel* precisionModel); // throw(GEOSException); /** * Inserted edges are checked to see if an identical edge already * exists. * If so, the edge is not inserted, but its label is merged * with the existing edge. * * The function takes responsibility of releasing the Edge parameter * memory when appropriate. */ void insertUniqueEdge(geomgraph::Edge* e); void createSubgraphs(geomgraph::PlanarGraph* graph, std::vector& list); /** * Completes the building of the input subgraphs by * depth-labelling them, * and adds them to the PolygonBuilder. * The subgraph list must be sorted in rightmost-coordinate order. * * @param subgraphList the subgraphs to build * @param polyBuilder the PolygonBuilder which will build * the final polygons */ void buildSubgraphs(const std::vector& subgraphList, overlay::PolygonBuilder& polyBuilder); /// \brief /// Return the externally-set noding::Noder OR a newly created /// one using the given precisionModel. /// /// NOTE: if an externally-set noding::Noder is available no /// check is performed to ensure it will use the /// given PrecisionModel /// noding::Noder* getNoder(const geom::PrecisionModel* precisionModel); /** * Gets the standard result for an empty buffer. * Since buffer always returns a polygonal result, * this is chosen to be an empty polygon. * * @return the empty result geometry, transferring ownership to caller. */ std::unique_ptr createEmptyResultGeometry() const; // Declare type as noncopyable BufferBuilder(const BufferBuilder& other) = delete; BufferBuilder& operator=(const BufferBuilder& rhs) = delete; }; } // namespace geos::operation::buffer } // namespace geos::operation } // namespace geos #ifdef _MSC_VER #pragma warning(pop) #endif