Document the named parameter point_map and use it in the issue

Kernel_23/include/CGAL/Kernel/function_objects.h

@@ -2650,7 +2650,7 @@ namespace CommonKernelFunctors {
     {
       CGAL_kernel_precondition(! K().collinear_3_object()(p,q,r) );
       Vector_3 res = CGAL::cross_product(q-p, r-p);
-      res = res / CGAL::approximate_sqrt(res.squared_length());
+      res = res / sqrt(res.squared_length());
       return res;
     }
   };

Stream_support/include/CGAL/IO/GOCAD.h

@@ -331,6 +331,13 @@ bool write_GOCAD(std::ostream& os,
  * \param np optional sequence of \ref bgl_namedparameters "Named Parameters" among the ones listed below
  *
  * \cgalNamedParamsBegin
+ *   \cgalParamNBegin{point_map}
+ *     \cgalParamDescription{a property map associating points with floating point coordinates to the elements of the point set `points`}
+ *     \cgalParamType{a model of `ReadablePropertyMap` whose key type is the value type
+ *                    of the iterator of `PointRange` and value type is a point type with floating point coordinates}
+ *     \cgalParamDefault{`CGAL::Identity_property_map<geom_traits::Point_3>`}
+ *   \cgalParamNEnd
+ *
  *   \cgalParamNBegin{stream_precision}
  *     \cgalParamDescription{a parameter used to set the precision (i.e. how many digits are generated) of the output stream}
  *     \cgalParamType{int}

Stream_support/include/CGAL/IO/OBJ.h

@@ -314,6 +314,13 @@ bool read_OBJ(const std::string& fname,
  * \param np optional sequence of \ref bgl_namedparameters "Named Parameters" among the ones listed below
  *
  * \cgalNamedParamsBegin
+ *   \cgalParamNBegin{point_map}
+ *     \cgalParamDescription{a property map associating points with floating point coordinates to the elements of the point set `points`}
+ *     \cgalParamType{a model of `ReadablePropertyMap` whose key type is the value type
+ *                    of the iterator of `PointRange` and value type is a point type with floating point coordinates}
+ *     \cgalParamDefault{`CGAL::Identity_property_map<geom_traits::Point_3>`}
+ *   \cgalParamNEnd
+ *
  *   \cgalParamNBegin{stream_precision}
  *     \cgalParamDescription{a parameter used to set the precision (i.e. how many digits are generated) of the output stream}
  *     \cgalParamType{int}

Stream_support/include/CGAL/IO/OFF.h

@@ -267,6 +267,13 @@ bool read_OFF(const std::string& fname,
  * \param np optional sequence of \ref bgl_namedparameters "Named Parameters" among the ones listed below
  *
  * \cgalNamedParamsBegin
+ *   \cgalParamNBegin{point_map}
+ *     \cgalParamDescription{a property map associating points with floating point coordinates to the elements of the point set `points`}
+ *     \cgalParamType{a model of `ReadablePropertyMap` whose key type is the value type
+ *                    of the iterator of `PointRange` and value type is a point type with floating point coordinates}
+ *     \cgalParamDefault{`CGAL::Identity_property_map<geom_traits::Point_3>`}
+ *   \cgalParamNEnd
+ * 
  *   \cgalParamNBegin{stream_precision}
  *     \cgalParamDescription{a parameter used to set the precision (i.e. how many digits are generated) of the output stream}
  *     \cgalParamType{int}
@@ -308,6 +315,13 @@ bool write_OFF(std::ostream& os,
  * \param np optional sequence of \ref bgl_namedparameters "Named Parameters" among the ones listed below
  *
  * \cgalNamedParamsBegin
+ *   \cgalParamNBegin{point_map}
+ *     \cgalParamDescription{a property map associating points with floating point coordinates to the elements of the point set `points`}
+ *     \cgalParamType{a model of `ReadablePropertyMap` whose key type is the value type
+ *                    of the iterator of `PointRange` and value type is a point type with floating point coordinates}
+ *     \cgalParamDefault{`CGAL::Identity_property_map<geom_traits::Point_3>`}
+ *   \cgalParamNEnd
+ * 
  *   \cgalParamNBegin{stream_precision}
  *     \cgalParamDescription{a parameter used to set the precision (i.e. how many digits are generated) of the output stream}
  *     \cgalParamType{int}

Stream_support/include/CGAL/IO/STL.h

@@ -319,10 +319,10 @@ bool write_STL(std::ostream& os,
 
       const Vector_3 n = collinear(p,q,r) ? Vector_3(1,0,0) : unit_normal(p,q,r);
 
-      const float coords[12] = { static_cast<float>(to_double(n.x())), static_cast<float>(to_double(n.y())), static_cast<float>(to_double(n.z())),
+      const float coords[12] = { static_cast<float>(n.x()), static_cast<float>(n.y()), static_cast<float>(n.z()),
-                                 static_cast<float>(to_double(p.x())), static_cast<float>(to_double(p.y())), static_cast<float>(to_double(p.z())),
+                                 static_cast<float>(p.x()), static_cast<float>(p.y()), static_cast<float>(p.z()),
-                                 static_cast<float>(to_double(q.x())), static_cast<float>(to_double(q.y())), static_cast<float>(to_double(q.z())),
+                                 static_cast<float>(q.x()), static_cast<float>(q.y()), static_cast<float>(q.z()),
-                                 static_cast<float>(to_double(r.x())), static_cast<float>(to_double(r.y())), static_cast<float>(to_double(r.z())) };
+                                 static_cast<float>(r.x()), static_cast<float>(r.y()), static_cast<float>(r.z()) };
 
       for(int i=0; i<12; ++i)
         os.write(reinterpret_cast<const char *>(&coords[i]), sizeof(coords[i]));

Stream_support/include/CGAL/IO/polygon_soup_io.h

@@ -142,6 +142,13 @@ bool read_polygon_soup(const std::string& fname,
  * \param np optional \ref bgl_namedparameters "Named Parameters" described below
  *
  * \cgalNamedParamsBegin
+ *   \cgalParamNBegin{point_map}
+ *     \cgalParamDescription{a property map associating points with floating point coordinates to the elements of the point set `points`}
+ *     \cgalParamType{a model of `ReadablePropertyMap` whose key type is the value type
+ *                    of the iterator of `PointRange` and value type is a point type with floating point coordinates}
+ *     \cgalParamDefault{`CGAL::Identity_property_map<geom_traits::Point_3>`}
+ *   \cgalParamNEnd
+ *
  *   \cgalParamNBegin{verbose}
  *     \cgalParamDescription{indicates whether output warnings and error messages should be printed or not.}
  *     \cgalParamType{Boolean}

Stream_support/test/Stream_support/issue_9071.cpp

@@ -2,13 +2,16 @@
 #include <vector>
 
 #include <CGAL/Exact_predicates_exact_constructions_kernel.h>
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
 #include <CGAL/IO/polygon_soup_io.h>
 
 using Kernel = CGAL::Exact_predicates_exact_constructions_kernel;
+using Epick = CGAL::Exact_predicates_inexact_constructions_kernel;
 
 int main() {
   std::vector<Kernel::Point_3> points;
   std::vector<std::array<std::size_t, 3>> polygons;
-  CGAL::IO::write_polygon_soup("xxx.off", points, polygons, CGAL::parameters::stream_precision(17));
+  auto pm = CGAL::make_cartesian_converter_property_map<Epick::Point_3>(CGAL::make_identity_property_map(Kernel::Point_3()));
+  CGAL::IO::write_polygon_soup("xxx.off", points, polygons, CGAL::parameters::stream_precision(17).point_map(pm));
   return 0;
 }