Initial implementation of new proj7 APIs support

SConstruct

@@ -1,6 +1,6 @@
 # This file is part of Mapnik (c++ mapping toolkit)
 #
-# Copyright (C) 2017 Artem Pavlenko
+# Copyright (C) 2021 Artem Pavlenko
 #
 # Mapnik is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
@@ -79,7 +79,7 @@ SCONF_TEMP_DIR = '.sconf_temp'
 BOOST_SEARCH_PREFIXES = ['/usr/local','/opt/local','/sw','/usr',]
 BOOST_MIN_VERSION = '1.61'
 #CAIRO_MIN_VERSION = '1.8.0'
-
+PROJ_MIN_VERSION = (7, 2, 0)
 HARFBUZZ_MIN_VERSION = (0, 9, 34)
 HARFBUZZ_MIN_VERSION_STRING = "%s.%s.%s" % HARFBUZZ_MIN_VERSION
 
@@ -92,7 +92,7 @@ pretty_dep_names = {
     'gdal':'GDAL C++ library | configured using gdal-config program | try setting GDAL_CONFIG SCons option | more info: https://github.com/mapnik/mapnik/wiki/GDAL',
     'ogr':'OGR-enabled GDAL C++ Library | configured using gdal-config program | try setting GDAL_CONFIG SCons option | more info: https://github.com/mapnik/mapnik/wiki/OGR',
     'cairo':'Cairo C library | configured using pkg-config | try setting PKG_CONFIG_PATH SCons option',
-    'proj':'Proj.4 C Projections library | configure with PROJ_LIBS & PROJ_INCLUDES | more info: http://trac.osgeo.org/proj/',
+    'proj':'Proj C Projections library | configure with PROJ_LIBS & PROJ_INCLUDES | more info: http://trac.osgeo.org/proj/',
     'pg':'Postgres C Library required for PostGIS plugin | configure with pg_config program or configure with PG_LIBS & PG_INCLUDES | more info: https://github.com/mapnik/mapnik/wiki/PostGIS',
     'sqlite3':'SQLite3 C Library | configure with SQLITE_LIBS & SQLITE_INCLUDES | more info: https://github.com/mapnik/mapnik/wiki/SQLite',
     'jpeg':'JPEG C library | configure with JPEG_LIBS & JPEG_INCLUDES',
@@ -116,7 +116,7 @@ pretty_dep_names = {
     'boost_regex_icu':'libboost_regex built with optional ICU unicode support is needed for unicode regex support in mapnik.',
     'sqlite_rtree':'The SQLite plugin requires libsqlite3 built with RTREE support (-DSQLITE_ENABLE_RTREE=1)',
     'pgsql2sqlite_rtree':'The pgsql2sqlite program requires libsqlite3 built with RTREE support (-DSQLITE_ENABLE_RTREE=1)',
-    'PROJ_LIB':'The directory where proj4 stores its data files. Must exist for proj4 to work correctly',
+    'PROJ_LIB':'The directory where proj stores its data files. Must exist for proj to work correctly',
     'GDAL_DATA':'The directory where GDAL stores its data files. Must exist for GDAL to work correctly',
     'ICU_DATA':'The directory where icu stores its data files. If ICU reports a path, it must exist. ICU can also be built without .dat files and in that case this path is empty'
     }
@@ -422,7 +422,7 @@ opts.AddVariables(
     BoolVariable('WEBP', 'Build Mapnik with WEBP read', 'True'),
     PathVariable('WEBP_INCLUDES', 'Search path for libwebp include files', '/usr/include', PathVariable.PathAccept),
     PathVariable('WEBP_LIBS','Search path for libwebp library files','/usr/' + LIBDIR_SCHEMA_DEFAULT, PathVariable.PathAccept),
-    BoolVariable('PROJ', 'Build Mapnik with proj4 support to enable transformations between many different projections', 'True'),
+    BoolVariable('PROJ', 'Build Mapnik with proj support to enable transformations between many different projections', 'True'),
     PathVariable('PROJ_INCLUDES', 'Search path for PROJ.4 include files', '/usr/include', PathVariable.PathAccept),
     PathVariable('PROJ_LIBS', 'Search path for PROJ.4 library files', '/usr/' + LIBDIR_SCHEMA_DEFAULT, PathVariable.PathAccept),
     ('PG_INCLUDES', 'Search path for libpq (postgres client) include files', ''),
@@ -940,59 +940,48 @@ def CheckProjData(context, silent=False):
         context.Message('Checking for PROJ_LIB directory...')
     ret, out = context.TryRun("""
 
-// This is narly, could eventually be replaced using https://github.com/OSGeo/proj.4/pull/551]
-#include <proj_api.h>
+#include <proj.h>
 #include <iostream>
-#include <cstring>
+#include <sstream>
+#include <vector>
+#include <string>
+#include <fstream>
 
-static void my_proj4_logger(void * user_data, int /*level*/, const char * msg)
+std::vector<std::string> split_searchpath(std::string const& paths)
 {
-    std::string* posMsg = static_cast<std::string*>(user_data);
-    *posMsg += msg;
-}
+    std::vector<std::string> output;
+    std::stringstream ss(paths);
+    std::string path;
 
-// https://github.com/OSGeo/gdal/blob/ddbf6d39aa4b005a77ca4f27c2d61a3214f336f8/gdal/alg/gdalapplyverticalshiftgrid.cpp#L616-L633
-
-std::string find_proj_path(const char * pszFilename) {
-    std::string osMsg;
-    std::string osFilename;
-    projCtx ctx = pj_ctx_alloc();
-    pj_ctx_set_app_data(ctx, &osMsg);
-    pj_ctx_set_debug(ctx, PJ_LOG_DEBUG_MAJOR);
-    pj_ctx_set_logger(ctx, my_proj4_logger);
-    PAFile f = pj_open_lib(ctx, pszFilename, "rb");
-    if( f )
-    {
-        pj_ctx_fclose(ctx, f);
-    }
-    size_t nPos = osMsg.find("fopen(");
-    if( nPos != std::string::npos )
+    for( std::string path;std::getline(ss, path, ':');)
     {
-        osFilename = osMsg.substr(nPos + strlen("fopen("));
-        nPos = osFilename.find(")");
-        if( nPos != std::string::npos )
-            osFilename = osFilename.substr(0, nPos);
+        output.push_back(path);
     }
-    pj_ctx_free(ctx);
-    return osFilename;
+    return output;
 }
 
-
-int main() {
-    std::string result = find_proj_path(" ");
-    std::cout << result;
-    if (result.empty()) {
-        return -1;
+int main()
+{
+    PJ_INFO info = proj_info();
+    std::string result = info.searchpath;
+    for (auto path : split_searchpath(result))
+    {
+        std::ifstream file(path + "/proj.db");
+        if (file)
+        {
+            std::cout << path;
+            return 0;
+        }
     }
-    return 0;
+    return -1;
 }
 
 """, '.cpp')
     value = out.strip()
     if silent:
         context.did_show_result=1
     if ret:
-        context.Result('pj_open_lib returned %s' % value)
+        context.Result('proj_info.searchpath returned %s' % value)
     else:
         context.Result('Failed to detect (mapnik-config will have null value)')
     return value
@@ -1565,7 +1554,7 @@ if not preconfigured:
         env['SKIPPED_DEPS'].append('jpeg')
 
     if env['PROJ']:
-        OPTIONAL_LIBSHEADERS.append(['proj', 'proj_api.h', False,'C','-DMAPNIK_USE_PROJ4'])
+        OPTIONAL_LIBSHEADERS.append(['proj', 'proj.h', False,'C','-DMAPNIK_USE_PROJ'])
         inc_path = env['%s_INCLUDES' % 'PROJ']
         lib_path = env['%s_LIBS' % 'PROJ']
         env.AppendUnique(CPPPATH = fix_path(inc_path))

benchmark/data/gdal-wgs.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE Map[]>
 <Map
-  srs="+init=epsg:4326"
+  srs="epsg:4326"
   background-color="#dfd8c9">
 
 <Style name="style">
@@ -10,7 +10,7 @@
   </Rule>
 </Style>
 <Layer name="layer"
-  srs="+init=epsg:4326">
+  srs="epsg:4326">
     <StyleName>style</StyleName>
     <Datasource>
        <Parameter name="file">./valid.geotiff.tif</Parameter>

benchmark/data/raster-wgs.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!DOCTYPE Map[]>
 <Map
-  srs="+init=epsg:4326"
+  srs="epsg:4326"
   background-color="#dfd8c9">
 
 <Style name="style">
@@ -10,7 +10,7 @@
   </Rule>
 </Style>
 <Layer name="layer"
-  srs="+init=epsg:4326">
+  srs="epsg:4326">
     <StyleName>style</StyleName>
     <Datasource>
        <Parameter name="file">./valid.geotiff.tif</Parameter>

benchmark/src/test_noop_rendering.cpp

@@ -11,7 +11,7 @@
 #include <mapnik/feature_type_style.hpp>
 
 #include <memory>
-    
+
 class test : public benchmark::test_case
 {
 public:
@@ -24,7 +24,7 @@ class test : public benchmark::test_case
     }
     bool operator()() const
     {
-        mapnik::Map m(256,256,"+init=epsg:3857");
+        mapnik::Map m(256,256,"epsg:3857");
 
         mapnik::parameters params;
         params["type"]="memory";

benchmark/src/test_polygon_clipping.cpp

@@ -51,7 +51,7 @@ void render(mapnik::geometry::multi_polygon<double> const& geom,
     agg::pixfmt_rgba32_plain pixf(buf);
     ren_base renb(pixf);
     renderer ren(renb);
-    mapnik::proj_transform prj_trans(mapnik::projection("+init=epsg:4326"),mapnik::projection("+init=epsg:4326"));
+    mapnik::proj_transform prj_trans(mapnik::projection("epsg:4326"),mapnik::projection("epsg:4326"));
     ren.color(agg::rgba8(127,127,127,255));
     agg::rasterizer_scanline_aa<> ras;
     for (auto const& poly : geom)

benchmark/src/test_proj_transform1.cpp

@@ -56,13 +56,13 @@ class test : public benchmark::test_case
     }
 };
 
-// echo -180 -60 | cs2cs -f "%.10f" +init=epsg:4326 +to +init=epsg:3857
+// echo -180 -60 | cs2cs -f "%.10f" epsg:4326 +to epsg:3857
 int main(int argc, char** argv)
 {
     mapnik::box2d<double> from(-180,-80,180,80);
     mapnik::box2d<double> to(-20037508.3427892476,-15538711.0963092316,20037508.3427892476,15538711.0963092316);
-    std::string from_str("+init=epsg:4326");
-    std::string to_str("+init=epsg:3857");
+    std::string from_str("epsg:4326");
+    std::string to_str("epsg:3857");
     std::string from_str2("+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs");
     std::string to_str2("+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0.0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs +over");
     return benchmark::sequencer(argc, argv)

include/mapnik/layer.hpp

@@ -42,7 +42,7 @@ using datasource_ptr = std::shared_ptr<datasource>;
  * @brief A Mapnik map layer.
  *
  * Create a layer with a named string and, optionally, an srs string either
- * with a Proj.4 epsg code ('+init=epsg:<code>') or with a Proj.4 literal
+ * with a Proj.4 epsg code ('epsg:<code>') or with a Proj.4 literal
  * ('+proj=<literal>'). If no srs is specified it will default to
  * '+proj=longlat +ellps=WGS84 +datum=WGS84 +no_defs'
  */

include/mapnik/proj_transform.hpp

@@ -27,20 +27,20 @@
 #include <mapnik/config.hpp>
 #include <mapnik/util/noncopyable.hpp>
 #include <mapnik/geometry/point.hpp>
+#include <mapnik/projection.hpp>
 // stl
 #include <vector>
 
 namespace mapnik {
 
-class projection;
 template <typename T> class box2d;
 
 class MAPNIK_DECL proj_transform : private util::noncopyable
 {
 public:
     proj_transform(projection const& source,
                    projection const& dest);
-
+    ~proj_transform();
     bool equal() const;
     bool is_known() const;
     bool forward (double& x, double& y , double& z) const;
@@ -59,6 +59,8 @@ class MAPNIK_DECL proj_transform : private util::noncopyable
     mapnik::projection const& dest() const;
 
 private:
+    PJ_CONTEXT* ctx_ = nullptr;
+    PJ* transform_ = nullptr;
     projection const& source_;
     projection const& dest_;
     bool is_source_longlat_;

include/mapnik/projection.hpp

@@ -37,6 +37,13 @@ MAPNIK_DISABLE_WARNING_POP
 #include <string>
 #include <stdexcept>
 
+
+// fwd decl
+struct projCtx_t;
+struct PJconsts;
+using PJ_CONTEXT = struct projCtx_t;
+using PJ = struct PJconsts;
+
 namespace mapnik {
 
 class proj_init_error : public std::runtime_error
@@ -66,7 +73,7 @@ class MAPNIK_DECL projection
     void forward(double & x, double & y) const;
     void inverse(double & x,double & y) const;
     std::string expanded() const;
-    void init_proj4() const;
+    void init_proj() const;
 
 private:
     void swap (projection& rhs);
@@ -75,8 +82,8 @@ class MAPNIK_DECL projection
     std::string params_;
     bool defer_proj_init_;
     mutable bool is_geographic_;
-    mutable void * proj_;
-    mutable void * proj_ctx_;
+    mutable PJ * proj_;
+    mutable PJ_CONTEXT * proj_ctx_;
 };
 
 template <typename charT, typename traits>

src/build.py

@@ -76,7 +76,7 @@ def ldconfig(*args,**kwargs):
    lib_env['LIBS'].append('png')
    enabled_imaging_libraries.append('png_reader.cpp')
 
-if '-DMAPNIK_USE_PROJ4' in env['CPPDEFINES']:
+if '-DMAPNIK_USE_PROJ' in env['CPPDEFINES']:
    lib_env['LIBS'].append('proj')
 
 if '-DHAVE_TIFF' in env['CPPDEFINES']: