From ea7b2231816c81684e30a2f997648d05eb2fcefb Mon Sep 17 00:00:00 2001
From: Even Rouault <even.rouault@spatialys.com>
Date: Mon, 29 Jan 2024 22:19:05 +0100
Subject: [PATCH] Doc: reference C API that used to be proj_experimental.h

---
 .../development/reference/datatypes.rst       |  3 +
 .../development/reference/functions.rst       |  3 +
 src/proj.h                                    | 72 ++++++++++---------
 3 files changed, 46 insertions(+), 32 deletions(-)

diff --git a/docs/source/development/reference/datatypes.rst b/docs/source/development/reference/datatypes.rst
index 7cb61e1dc9..e8c3cd1e94 100644
--- a/docs/source/development/reference/datatypes.rst
+++ b/docs/source/development/reference/datatypes.rst
@@ -996,4 +996,7 @@ C API for ISO-19111 functionality
    :content-only:
    :members:
 
+.. doxygengroup:: iso19111_advanced_types
+   :project: doxygen_api
+   :content-only:
 
diff --git a/docs/source/development/reference/functions.rst b/docs/source/development/reference/functions.rst
index 8adb5c0279..5aa52ef495 100644
--- a/docs/source/development/reference/functions.rst
+++ b/docs/source/development/reference/functions.rst
@@ -1047,3 +1047,6 @@ will return an error when used with functions of this section.
    :project: doxygen_api
    :content-only:
 
+.. doxygengroup:: iso19111_advanced_functions
+   :project: doxygen_api
+   :content-only:
diff --git a/src/proj.h b/src/proj.h
index 1b42fae8be..88aca598c7 100644
--- a/src/proj.h
+++ b/src/proj.h
@@ -1511,7 +1511,7 @@ double PROJ_DLL proj_coordinate_metadata_get_epoch(PJ_CONTEXT *ctx,
 /* ------------------------------------------------------------------------- */
 
 /**
- * \defgroup advanced_cpp_binding Binding in C of advanced methods from the C++
+ * \defgroup iso19111_advanced_types C types for advanced methods from the C++
  * API
  * @{
  */
@@ -1546,9 +1546,6 @@ typedef struct {
     PJ_UNIT_TYPE unit_type;
 } PJ_AXIS_DESCRIPTION;
 
-PJ PROJ_DLL *proj_create_cs(PJ_CONTEXT *ctx, PJ_COORDINATE_SYSTEM_TYPE type,
-                            int axis_count, const PJ_AXIS_DESCRIPTION *axis);
-
 /** Type of Cartesian 2D coordinate system. */
 typedef enum {
     /* Easting-Norting */
@@ -1563,11 +1560,6 @@ typedef enum {
     PJ_CART2D_WESTING_SOUTHING,
 } PJ_CARTESIAN_CS_2D_TYPE;
 
-PJ PROJ_DLL *proj_create_cartesian_2D_cs(PJ_CONTEXT *ctx,
-                                         PJ_CARTESIAN_CS_2D_TYPE type,
-                                         const char *unit_name,
-                                         double unit_conv_factor);
-
 /** Type of Ellipsoidal 2D coordinate system. */
 typedef enum {
     /* Longitude-Latitude */
@@ -1576,11 +1568,6 @@ typedef enum {
     PJ_ELLPS2D_LATITUDE_LONGITUDE,
 } PJ_ELLIPSOIDAL_CS_2D_TYPE;
 
-PJ PROJ_DLL *proj_create_ellipsoidal_2D_cs(PJ_CONTEXT *ctx,
-                                           PJ_ELLIPSOIDAL_CS_2D_TYPE type,
-                                           const char *unit_name,
-                                           double unit_conv_factor);
-
 /** Type of Ellipsoidal 3D coordinate system. */
 typedef enum {
     /* Longitude-Latitude-Height(up) */
@@ -1589,6 +1576,45 @@ typedef enum {
     PJ_ELLPS3D_LATITUDE_LONGITUDE_HEIGHT,
 } PJ_ELLIPSOIDAL_CS_3D_TYPE;
 
+/** Description of a parameter value for a Conversion. */
+typedef struct {
+    /** Parameter name. */
+    const char *name;
+    /** Parameter authority name. */
+    const char *auth_name;
+    /** Parameter code. */
+    const char *code;
+    /** Parameter value. */
+    double value;
+    /** Name of unit in which parameter value is expressed. */
+    const char *unit_name;
+    /** Conversion factor to SI of the unit. */
+    double unit_conv_factor;
+    /** Type of unit */
+    PJ_UNIT_TYPE unit_type;
+} PJ_PARAM_DESCRIPTION;
+
+/**@}*/
+
+/**
+ * \defgroup iso19111_advanced_functions Binding in C of advanced methods from
+ * the C++ API
+ * @{
+ */
+
+PJ PROJ_DLL *proj_create_cs(PJ_CONTEXT *ctx, PJ_COORDINATE_SYSTEM_TYPE type,
+                            int axis_count, const PJ_AXIS_DESCRIPTION *axis);
+
+PJ PROJ_DLL *proj_create_cartesian_2D_cs(PJ_CONTEXT *ctx,
+                                         PJ_CARTESIAN_CS_2D_TYPE type,
+                                         const char *unit_name,
+                                         double unit_conv_factor);
+
+PJ PROJ_DLL *proj_create_ellipsoidal_2D_cs(PJ_CONTEXT *ctx,
+                                           PJ_ELLIPSOIDAL_CS_2D_TYPE type,
+                                           const char *unit_name,
+                                           double unit_conv_factor);
+
 PJ PROJ_DLL *
 proj_create_ellipsoidal_3D_cs(PJ_CONTEXT *ctx, PJ_ELLIPSOIDAL_CS_3D_TYPE type,
                               const char *horizontal_angular_unit_name,
@@ -1684,24 +1710,6 @@ PJ PROJ_DLL *proj_create_vertical_crs_ex(
 PJ PROJ_DLL *proj_create_compound_crs(PJ_CONTEXT *ctx, const char *crs_name,
                                       PJ *horiz_crs, PJ *vert_crs);
 
-/** Description of a parameter value for a Conversion. */
-typedef struct {
-    /** Parameter name. */
-    const char *name;
-    /** Parameter authority name. */
-    const char *auth_name;
-    /** Parameter code. */
-    const char *code;
-    /** Parameter value. */
-    double value;
-    /** Name of unit in which parameter value is expressed. */
-    const char *unit_name;
-    /** Conversion factor to SI of the unit. */
-    double unit_conv_factor;
-    /** Type of unit */
-    PJ_UNIT_TYPE unit_type;
-} PJ_PARAM_DESCRIPTION;
-
 PJ PROJ_DLL *proj_create_conversion(PJ_CONTEXT *ctx, const char *name,
                                     const char *auth_name, const char *code,
                                     const char *method_name,