scons: make libjpeg dependency optional (still required by default)

CHANGELOG

@@ -14,6 +14,8 @@ For a complete change history, see the SVN log.
 Mapnik Trunk
 ------------
 
+- Made libjpeg dependency optional at compile time and added mapnik2.has_jpeg() method to check for support in python (#545).
+
 - Fixed reading of PostGIS data on Big Endian systems (#515)
 
 - PostGIS: Added better support for alterative schemas (#500)

SConstruct

@@ -258,6 +258,7 @@ opts.AddVariables(
     ('ICU_LIB_NAME', 'The library name for icu (such as icuuc, sicuuc, or icucore)', 'icuuc'),
     PathVariable('PNG_INCLUDES', 'Search path for libpng include files', '/usr/include', PathVariable.PathAccept),
     PathVariable('PNG_LIBS','Search path for libpng include files','/usr/' + LIBDIR_SCHEMA, PathVariable.PathAccept),
+    BoolVariable('JPEG', 'Build Mapnik with JPEG read and write support', 'True'),    
     PathVariable('JPEG_INCLUDES', 'Search path for libjpeg include files', '/usr/include', PathVariable.PathAccept),
     PathVariable('JPEG_LIBS', 'Search path for libjpeg library files', '/usr/' + LIBDIR_SCHEMA, PathVariable.PathAccept),
     PathVariable('TIFF_INCLUDES', 'Search path for libtiff include files', '/usr/include', PathVariable.PathAccept),
@@ -779,6 +780,7 @@ if not preconfigured:
     else:
         env['SKIPPED_DEPS'].extend(['cairo','cairomm'])
 
+
     # allow for mac osx /usr/lib/libicucore.dylib compatibility
     # requires custom supplied headers since Apple does not include them
     # details: http://lists.apple.com/archives/xcode-users/2005/Jun/msg00633.html
@@ -797,11 +799,16 @@ if not preconfigured:
         ['png', 'png.h', True,'C'],
         ['tiff', 'tiff.h', True,'C'],
         ['z', 'zlib.h', True,'C'],
-        ['jpeg', ['stdio.h', 'jpeglib.h'], True,'C'],
         ['proj', 'proj_api.h', True,'C'],
         [env['ICU_LIB_NAME'],'unicode/unistr.h',True,'C++'],
     ]
 
+    if env['JPEG']:
+        env.Append(CXXFLAGS = '-DHAVE_JPEG')
+        LIBSHEADERS.append(['jpeg', ['stdio.h', 'jpeglib.h'], True,'C'])
+    else:
+        env['SKIPPED_DEPS'].extend(['jpeg'])
+
 
     # if requested, sort LIBPATH and CPPPATH before running CheckLibWithHeader tests
     if env['PRIORITIZE_LINKING']:

bindings/python/mapnik_image.cpp

@@ -30,13 +30,19 @@ extern "C"
 #include <boost/python.hpp>
 #include <boost/python/module.hpp>
 #include <boost/python/def.hpp>
+
 // mapnik
 #include <mapnik/graphics.hpp>
 #include <mapnik/image_util.hpp>
-#include <mapnik/jpeg_io.hpp>
 #include <mapnik/png_io.hpp>
 #include <mapnik/image_reader.hpp>
 #include <sstream>
+
+// jpeg
+#if defined(HAVE_JPEG)
+#include <mapnik/jpeg_io.hpp>
+#endif
+
 // cairo
 #if defined(HAVE_CAIRO) && defined(HAVE_PYCAIRO)
 #include <cairomm/surface.h>

bindings/python/mapnik_image_view.cpp

@@ -29,10 +29,14 @@ extern "C"
 #include <boost/python.hpp>
 #include <mapnik/image_util.hpp>
 #include <mapnik/image_view.hpp>
-#include <mapnik/jpeg_io.hpp>
 #include <mapnik/png_io.hpp>
 #include <sstream>
 
+// jpeg
+#if defined(HAVE_JPEG)
+#include <mapnik/jpeg_io.hpp>
+#endif
+
 using mapnik::image_data_32;
 using mapnik::image_view;
 using mapnik::save_to_file;

bindings/python/mapnik_python.cpp

@@ -256,6 +256,16 @@ unsigned mapnik_svn_revision()
 #endif
 }
 
+// indicator for jpeg read/write support within libmapnik
+bool has_jpeg()
+{
+#if defined(HAVE_JPEG)
+  return true;
+#else
+  return false;
+#endif
+}
+
 // indicator for cairo rendering support inside libmapnik
 bool has_cairo()
 {
@@ -495,6 +505,7 @@ BOOST_PYTHON_MODULE(_mapnik2)
     def("save_map_to_string", & save_map_to_string, save_map_to_string_overloads());
     def("mapnik_version", &mapnik_version,"Get the Mapnik version number");
     def("mapnik_svn_revision", &mapnik_svn_revision,"Get the Mapnik svn revision");
+    def("has_jpeg", &has_jpeg, "Get jpeg read/write support status");
     def("has_cairo", &has_cairo, "Get cairo library status");
     def("has_pycairo", &has_pycairo, "Get pycairo module status");
 

include/mapnik/image_util.hpp

@@ -77,10 +77,12 @@ template <typename T>
 void save_as_png(T const& image,
                  std::string const& filename);
 
+#if defined(HAVE_JPEG)
 template <typename T>
 void save_as_jpeg(std::string const& filename,
                   int quality,
                   T const& image);
+#endif
 
 inline bool is_png (std::string const& filename)
 {

include/mapnik/jpeg_io.hpp

@@ -21,6 +21,7 @@
  *****************************************************************************/
 
 //$Id$
+#if defined(HAVE_JPEG)
 
 #include <mapnik/global.hpp>
 
@@ -125,3 +126,5 @@ void save_as_jpeg(T1 & file,int quality, T2 const& image)
     jpeg_destroy_compress(&cinfo);
 }  
 }
+
+#endif

src/image_util.cpp

@@ -30,11 +30,15 @@ extern "C"
 // mapnik
 #include <mapnik/image_util.hpp>
 #include <mapnik/png_io.hpp>
-#include <mapnik/jpeg_io.hpp>
 #include <mapnik/graphics.hpp>
 #include <mapnik/memory.hpp>
 #include <mapnik/image_view.hpp>
 
+// jpeg
+#if defined(HAVE_JPEG)
+#include <mapnik/jpeg_io.hpp>
+#endif
+
 #ifdef HAVE_CAIRO
 #include <mapnik/cairo_renderer.hpp>
 #endif
@@ -149,6 +153,7 @@ void save_to_stream(T const& image,
             else
                 save_as_png256_hex(stream, image, colors, trans_mode, gamma);
         }
+#if defined(HAVE_JPEG)
         else if (boost::algorithm::istarts_with(type,std::string("jpeg")))
         {
             int quality = 85;
@@ -167,6 +172,7 @@ void save_to_stream(T const& image,
                 throw ImageWriterException("invalid jpeg quality: " + type.substr(4) + " not a number");
             }
         }
+#endif
         else throw ImageWriterException("unknown file type: " + type);
     } 
     else throw ImageWriterException("Could not write to empty stream" );

tests/python_tests/render_test.py

@@ -31,7 +31,8 @@ def test_render_image_to_file():
     
     i.background = mapnik2.Color('black')
 
-    i.save('test.jpg')
+    if mapnik2.has_jpeg():
+        i.save('test.jpg')
     i.save('test.png', 'png')
 
     if os.path.exists('test.jpg'):