default values for composite args to maintain api compatibility

bindings/python/mapnik_image.cpp

@@ -149,7 +149,7 @@ void blend (image_32 & im, unsigned x, unsigned y, image_32 const& im2, float op
 
 void composite(image_32 & im, image_32 & im2, mapnik::composite_mode_e mode, float opacity)
 {
-    mapnik::composite(im.data(),im2.data(),mode,opacity,true,true);
+    mapnik::composite(im.data(),im2.data(),mode,opacity,0,0,true,true);
 }
 
 #if defined(HAVE_CAIRO) && defined(HAVE_PYCAIRO)
@@ -207,7 +207,12 @@ void export_image()
         .def("set_color_to_alpha",&image_32::set_color_to_alpha, "Set a given color to the alpha channel of the Image")
         .def("set_alpha",&image_32::set_alpha, "Set the overall alpha channel of the Image")
         .def("blend",&blend)
-        .def("composite",&composite)
+        .def("composite",&composite,
+         ( arg("self"),
+           arg("image"),
+           arg("mode"),
+           arg("opacity")=1.0f
+         ))
         .def("set_pixel",&set_pixel)
         //TODO(haoyu) The method name 'tostring' might be confusing since they actually return bytes in Python 3
 

include/mapnik/image_compositing.hpp

@@ -74,15 +74,23 @@ enum composite_mode_e
 MAPNIK_DECL boost::optional<composite_mode_e> comp_op_from_string(std::string const& name);
 
 template <typename T1, typename T2>
-MAPNIK_DECL void composite(T1 & im, T2 & im2, int xdst, int ydst,
+MAPNIK_DECL void composite(T1 & im, T2 & im2,
-                           composite_mode_e mode, float opacity,
+                           composite_mode_e mode,
-                           bool premultiply_src, bool premultiply_dst);
+                           float opacity=1,
-
+                           int xdst=0,
-template <typename T1, typename T2>
+                           int ydst=0,
-MAPNIK_DECL void composite(T1 & im, T2 & im2, composite_mode_e mode, float opacity, bool premultiply_src, bool premultiply_dst);
+                           bool premultiply_src=true,
+                           bool premultiply_dst=true);
 
 #ifdef _MSC_VER
-template MAPNIK_DECL void composite<mapnik::image_data_32,mapnik::image_data_32>(mapnik::image_data_32 & im, mapnik::image_data_32 & im2, composite_mode_e mode, float opacity, bool premultiply_src, bool premultiply_dst);
+template MAPNIK_DECL void composite<mapnik::image_data_32,mapnik::image_data_32>(mapnik::image_data_32 & im,
+                           mapnik::image_data_32 & im2,
+                           composite_mode_e mode,
+                           float opacity,
+                           int xdst,
+                           int ydst,
+                           bool premultiply_src,
+                           bool premultiply_dst);
 #endif
 
 }

src/agg/agg_renderer.cpp

@@ -230,11 +230,11 @@ void agg_renderer<T>::end_style_processing(feature_type_style const& st)
     
     if (st.comp_op())
     {
-        composite(pixmap_.data(),current_buffer_->data(), *st.comp_op(), 1.0f, false,false);
+        composite(pixmap_.data(),current_buffer_->data(), *st.comp_op(), 1.0f, 0, 0, false, false);
     }   
     else if (blend_from)
     {                
-        composite(pixmap_.data(),current_buffer_->data(), src_over, 1.0f,false,false);
+        composite(pixmap_.data(),current_buffer_->data(), src_over, 1.0f, 0, 0, false,false);
     }
     
     // apply any 'direct' image filters    

src/agg/process_raster_symbolizer.cpp

@@ -77,7 +77,7 @@ void agg_renderer<T>::process(raster_symbolizer const& sym,
                              scale_factor,
                              sym.get_scaling());
 
-            composite(current_buffer_->data(), target.data_, start_x, start_y, sym.comp_op(), sym.get_opacity(), false , false);
+            composite(current_buffer_->data(), target.data_, sym.comp_op(), sym.get_opacity(), start_x, start_y, false, false);
         }
     }
 }

src/image_compositing.cpp

@@ -81,7 +81,12 @@ boost::optional<composite_mode_e> comp_op_from_string(std::string const& name)
 }
 
 template <typename T1, typename T2>
-void composite(T1 & im, T2 & im2, int xdst, int ydst, composite_mode_e mode, float opacity, bool premultiply_src, bool premultiply_dst)
+void composite(T1 & im, T2 & im2, composite_mode_e mode,
+               float opacity,
+               int xdst,
+               int ydst,
+               bool premultiply_src,
+               bool premultiply_dst)
 {
     typedef agg::rgba8 color;
     typedef agg::order_rgba order;
@@ -103,14 +108,6 @@ void composite(T1 & im, T2 & im2, int xdst, int ydst, composite_mode_e mode, flo
     ren.blend_from(pixf_mask,0, xdst,ydst,unsigned(255*opacity));
 }
 
-template <typename T1, typename T2>
+template void composite<mapnik::image_data_32,mapnik::image_data_32>(mapnik::image_data_32&, mapnik::image_data_32& ,composite_mode_e, float, int, int, bool, bool);
-void composite(T1 & im, T2 & im2, composite_mode_e mode, float opacity, bool premultiply_src, bool premultiply_dst)
-{
-    composite(im, im2, 0, 0, mode, opacity, premultiply_src, premultiply_dst);
-}
-
-template void composite<mapnik::image_data_32,mapnik::image_data_32>(mapnik::image_data_32&, mapnik::image_data_32& , int, int,composite_mode_e, float, bool, bool);
-
-template void composite<mapnik::image_data_32,mapnik::image_data_32>(mapnik::image_data_32&, mapnik::image_data_32&, composite_mode_e, float, bool, bool);
 
 }