Add GEOSGeom_transformXYZ (#1157)

* Add GEOSGeom_transformXYZ
libgeos · Sep 9, 2024 · 1765c12 · 1765c12
1 parent 1c0840a
commit 1765c12
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Showing 4 changed files with 416 additions and 2 deletions.
diff --git a/capi/geos_c.cpp b/capi/geos_c.cpp
@@ -663,6 +663,12 @@ extern "C" {
     }
 
 
+    Geometry*
+    GEOSGeom_transformXYZ(const GEOSGeometry* g, GEOSTransformXYZCallback callback, void* userdata) {
+        return GEOSGeom_transformXYZ_r(handle, g, callback, userdata);
+    }
+
+
 //-------------------------------------------------------------------
 // memory management functions
 //------------------------------------------------------------------

diff --git a/capi/geos_c.h.in b/capi/geos_c.h.in
@@ -284,7 +284,7 @@ typedef int (*GEOSDistanceCallback)(
 /**
 * Callback function for use in GEOSGeom_transformXY.
 * Allows custom function to be applied to x and y values for each coordinate
-* in a geometry.  Z values are unchanged by this function.
+* in a geometry.  Z and M values are unchanged by this function.
 * Extra data for the calculation can be passed via the userdata.
 *
 * \param x coordinate value to be updated
@@ -299,6 +299,26 @@ typedef int (*GEOSTransformXYCallback)(
     void* userdata);
 
 
+/**
+* Callback function for use in GEOSGeom_transformXYZ.
+* Allows custom function to be applied to x, y and z values for each coordinate
+* in a geometry.  M values are unchanged by this function.
+* Extra data for the calculation can be passed via the userdata.
+*
+* \param x coordinate value to be updated
+* \param y coordinate value to be updated
+* \param z coordinate value to be updated
+* \param userdata extra data for the calculation
+*
+* \return 1 if calculation succeeded, 0 on failure
+*/
+typedef int (*GEOSTransformXYZCallback)(
+    double* x,
+    double* y,
+    double* z,
+    void* userdata);
+
+
 /* ========== Interruption ========== */
 
 /**
@@ -1821,6 +1841,13 @@ extern GEOSGeometry GEOS_DLL *GEOSGeom_transformXY_r(
     GEOSTransformXYCallback callback,
     void* userdata);
 
+/** \see GEOSGeom_transformXYZ */
+extern GEOSGeometry GEOS_DLL *GEOSGeom_transformXYZ_r(
+    GEOSContextHandle_t handle,
+    const GEOSGeometry* g,
+    GEOSTransformXYZCallback callback,
+    void* userdata);
+
 /* ========= Algorithms ========= */
 
 /** \see GEOSOrientationIndex */
@@ -4696,7 +4723,7 @@ extern int GEOS_DLL GEOSHilbertCode(
 /**
 * Apply XY coordinate transform callback to all coordinates in a copy of
 * input geometry.  If the callback returns an error, returned geometry will be
-* NULL.  Z values, if present, are not modified by this function.
+* NULL.  Z and M values, if present, are not modified by this function.
 * \param[in] g Input geometry
 * \param[in] callback a function to be executed for each coordinate in the
                 geometry.  The callback takes 3 parameters: x and y coordinate
@@ -4712,6 +4739,25 @@ extern GEOSGeometry GEOS_DLL *GEOSGeom_transformXY(
     GEOSTransformXYCallback callback,
     void* userdata);
 
+/**
+* Apply XYZ coordinate transform callback to all coordinates in a copy of
+* input geometry.  If the callback returns an error, returned geometry will be
+* NULL.  M values, if present, are not modified by this function.
+* \param[in] g Input geometry
+* \param[in] callback a function to be executed for each coordinate in the
+                geometry.  The callback takes 4 parameters: x, y and z coordinate
+                values to be updated and a void userdata pointer.
+* \param userdata an optional pointer to pe passed to 'callback' as an argument
+* \return a copy of the input geometry with transformed coordinates.
+* Caller must free with GEOSGeom_destroy().
+*
+* \since 3.13
+*/
+extern GEOSGeometry GEOS_DLL *GEOSGeom_transformXYZ(
+    const GEOSGeometry* g,
+    GEOSTransformXYZCallback callback,
+    void* userdata);
+
 /**
 * Snaps the vertices and segments of the first geometry to vertices of the
 * second geometry within the given tolerance.

diff --git a/capi/geos_ts_c.cpp b/capi/geos_ts_c.cpp
@@ -1655,6 +1655,35 @@ extern "C" {
     }
 
 
+    Geometry*
+    GEOSGeom_transformXYZ_r(GEOSContextHandle_t handle, const GEOSGeometry* g, GEOSTransformXYZCallback callback, void* userdata) {
+
+        struct TransformFilter final: public geos::geom::CoordinateFilter {
+            TransformFilter(GEOSTransformXYZCallback p_callback,
+                            void* p_userdata) :
+                            m_callback(p_callback),
+                            m_userdata(p_userdata) {}
+
+            void filter_rw(Coordinate* c) const override {
+                if (!m_callback(&(c->x), &(c->y), &(c->z), m_userdata)) {
+                    throw std::runtime_error(std::string("Failed to transform coordinates."));
+                }
+            }
+
+            GEOSTransformXYZCallback m_callback;
+            void* m_userdata;
+        };
+
+        return execute(handle, [&]() {
+            TransformFilter filter(callback, userdata);
+            auto ret = g->clone();
+            ret->apply_rw(&filter);
+            ret->geometryChanged();
+            return ret.release();
+        });
+    }
+
+
 //-------------------------------------------------------------------
 // memory management functions
 //------------------------------------------------------------------