Line data    Source code

       1             : /******************************************************************************
       2             :  *
       3             :  * Project:  GDAL
       4             :  * Purpose:  "gdal vector buffer"
       5             :  * Author:   Even Rouault <even dot rouault at spatialys.com>
       6             :  *
       7             :  ******************************************************************************
       8             :  * Copyright (c) 2025, Even Rouault <even dot rouault at spatialys.com>
       9             :  *
      10             :  * SPDX-License-Identifier: MIT
      11             :  ****************************************************************************/
      12             : 
      13             : #include "gdalalg_vector_buffer.h"
      14             : 
      15             : #include "gdal_priv.h"
      16             : #include "ogrsf_frmts.h"
      17             : 
      18             : //! @cond Doxygen_Suppress
      19             : 
      20             : #ifndef _
      21             : #define _(x) (x)
      22             : #endif
      23             : 
      24             : /************************************************************************/
      25             : /*                     GDALVectorBufferAlgorithm()                      */
      26             : /************************************************************************/
      27             : 
      28          88 : GDALVectorBufferAlgorithm::GDALVectorBufferAlgorithm(bool standaloneStep)
      29             :     : GDALVectorGeomAbstractAlgorithm(NAME, DESCRIPTION, HELP_URL,
      30          88 :                                       standaloneStep, m_opts)
      31             : {
      32             :     AddArg("distance", 0, _("Distance to which to extend the geometry."),
      33         176 :            &m_opts.m_distance)
      34          88 :         .SetPositional()
      35          88 :         .SetRequired();
      36         176 :     AddArg("endcap-style", 0, _("Endcap style."), &m_opts.m_endCapStyle)
      37          88 :         .SetChoices("round", "flat", "square")
      38          88 :         .SetDefault(m_opts.m_endCapStyle);
      39         176 :     AddArg("join-style", 0, _("Join style."), &m_opts.m_joinStyle)
      40          88 :         .SetChoices("round", "mitre", "bevel")
      41          88 :         .SetDefault(m_opts.m_joinStyle);
      42             :     AddArg("mitre-limit", 0,
      43             :            _("Mitre ratio limit (only affects mitered join style)."),
      44         176 :            &m_opts.m_mitreLimit)
      45          88 :         .SetDefault(m_opts.m_mitreLimit)
      46          88 :         .SetMinValueIncluded(0);
      47             :     AddArg("quadrant-segments", 0,
      48             :            _("Number of line segments used to approximate a quarter circle."),
      49         176 :            &m_opts.m_quadrantSegments)
      50          88 :         .SetDefault(m_opts.m_quadrantSegments)
      51          88 :         .SetMinValueIncluded(1);
      52             :     AddArg("side", 0,
      53             :            _("Sets whether the computed buffer should be single-sided or not."),
      54         176 :            &m_opts.m_side)
      55          88 :         .SetChoices("both", "left", "right")
      56          88 :         .SetDefault(m_opts.m_side);
      57          88 : }
      58             : 
      59             : #ifdef HAVE_GEOS
      60             : 
      61             : namespace
      62             : {
      63             : 
      64             : /************************************************************************/
      65             : /*                    GDALVectorBufferAlgorithmLayer                    */
      66             : /************************************************************************/
      67             : 
      68             : class GDALVectorBufferAlgorithmLayer final
      69             :     : public GDALVectorGeomOneToOneAlgorithmLayer<GDALVectorBufferAlgorithm>
      70             : {
      71             :   public:
      72           8 :     GDALVectorBufferAlgorithmLayer(
      73             :         OGRLayer &oSrcLayer, const GDALVectorBufferAlgorithm::Options &opts)
      74           8 :         : GDALVectorGeomOneToOneAlgorithmLayer<GDALVectorBufferAlgorithm>(
      75             :               oSrcLayer, opts),
      76           8 :           m_poFeatureDefn(oSrcLayer.GetLayerDefn()->Clone())
      77             :     {
      78          16 :         for (int i = 0; i < m_poFeatureDefn->GetGeomFieldCount(); ++i)
      79             :         {
      80           8 :             if (IsSelectedGeomField(i))
      81             :             {
      82           8 :                 m_poFeatureDefn->GetGeomFieldDefn(i)->SetType(wkbMultiPolygon);
      83             :             }
      84             :         }
      85             : 
      86             :         m_aosBufferOptions.SetNameValue("ENDCAP_STYLE",
      87           8 :                                         opts.m_endCapStyle.c_str());
      88           8 :         m_aosBufferOptions.SetNameValue("JOIN_STYLE", opts.m_joinStyle.c_str());
      89             :         m_aosBufferOptions.SetNameValue("MITRE_LIMIT",
      90           8 :                                         CPLSPrintf("%.17g", opts.m_mitreLimit));
      91             :         m_aosBufferOptions.SetNameValue(
      92           8 :             "QUADRANT_SEGMENTS", CPLSPrintf("%d", opts.m_quadrantSegments));
      93             :         m_aosBufferOptions.SetNameValue("SINGLE_SIDED",
      94           8 :                                         m_opts.m_side != "both" ? "YES" : "NO");
      95           8 :     }
      96             : 
      97          21 :     const OGRFeatureDefn *GetLayerDefn() const override
      98             :     {
      99          21 :         return m_poFeatureDefn.get();
     100             :     }
     101             : 
     102             :   protected:
     103             :     using GDALVectorGeomOneToOneAlgorithmLayer::TranslateFeature;
     104             : 
     105             :     std::unique_ptr<OGRFeature>
     106             :     TranslateFeature(std::unique_ptr<OGRFeature> poSrcFeature) const override;
     107             : 
     108             :   private:
     109             :     CPLStringList m_aosBufferOptions{};
     110             :     const OGRFeatureDefnRefCountedPtr m_poFeatureDefn;
     111             : 
     112             :     CPL_DISALLOW_COPY_ASSIGN(GDALVectorBufferAlgorithmLayer)
     113             : };
     114             : 
     115             : /************************************************************************/
     116             : /*                          TranslateFeature()                          */
     117             : /************************************************************************/
     118             : 
     119          30 : std::unique_ptr<OGRFeature> GDALVectorBufferAlgorithmLayer::TranslateFeature(
     120             :     std::unique_ptr<OGRFeature> poSrcFeature) const
     121             : {
     122          30 :     const int nGeomFieldCount = m_poFeatureDefn->GetGeomFieldCount();
     123          60 :     for (int i = 0; i < nGeomFieldCount; ++i)
     124             :     {
     125          30 :         if (IsSelectedGeomField(i))
     126             :         {
     127          30 :             if (auto poGeom = std::unique_ptr<OGRGeometry>(
     128          60 :                     poSrcFeature->StealGeometry(i)))
     129             :             {
     130          23 :                 poGeom.reset(poGeom->BufferEx(m_opts.m_distance,
     131             :                                               m_aosBufferOptions.List()));
     132          23 :                 if (poGeom)
     133             :                 {
     134             :                     const auto poGeomFieldDefn =
     135          23 :                         m_poFeatureDefn->GetGeomFieldDefn(i);
     136          69 :                     poGeom = OGRGeometryFactory::forceTo(
     137          46 :                         std::move(poGeom), poGeomFieldDefn->GetType());
     138          23 :                     if (poGeom)
     139             :                     {
     140          46 :                         poGeom->assignSpatialReference(
     141          23 :                             poGeomFieldDefn->GetSpatialRef());
     142          23 :                         poSrcFeature->SetGeomField(i, std::move(poGeom));
     143             :                     }
     144             :                 }
     145             :             }
     146             :         }
     147             :     }
     148             : 
     149          30 :     poSrcFeature->SetFDefnUnsafe(m_poFeatureDefn.get());
     150          30 :     return poSrcFeature;
     151             : }
     152             : 
     153             : }  // namespace
     154             : 
     155             : #endif  // HAVE_GEOS
     156             : 
     157             : /************************************************************************/
     158             : /*             GDALVectorBufferAlgorithm::CreateAlgLayer()              */
     159             : /************************************************************************/
     160             : 
     161             : std::unique_ptr<OGRLayerWithTranslateFeature>
     162           8 : GDALVectorBufferAlgorithm::CreateAlgLayer([[maybe_unused]] OGRLayer &srcLayer)
     163             : {
     164             : #ifdef HAVE_GEOS
     165           8 :     return std::make_unique<GDALVectorBufferAlgorithmLayer>(srcLayer, m_opts);
     166             : #else
     167             :     CPLAssert(false);
     168             :     return nullptr;
     169             : #endif
     170             : }
     171             : 
     172             : /************************************************************************/
     173             : /*                 GDALVectorBufferAlgorithm::RunStep()                 */
     174             : /************************************************************************/
     175             : 
     176           8 : bool GDALVectorBufferAlgorithm::RunStep(GDALPipelineStepRunContext &ctxt)
     177             : {
     178             : #ifdef HAVE_GEOS
     179           8 :     if (m_opts.m_side == "right")
     180           1 :         m_opts.m_distance = -m_opts.m_distance;
     181             : 
     182           8 :     return GDALVectorGeomAbstractAlgorithm::RunStep(ctxt);
     183             : #else
     184             :     (void)ctxt;
     185             :     ReportError(CE_Failure, CPLE_NotSupported,
     186             :                 "This algorithm is only supported for builds against GEOS");
     187             :     return false;
     188             : #endif
     189             : }
     190             : 
     191             : GDALVectorBufferAlgorithmStandalone::~GDALVectorBufferAlgorithmStandalone() =
     192             :     default;
     193             : 
     194             : //! @endcond