From 95cfb061afe3d3d30e137db54418aa87cdd34be6 Mon Sep 17 00:00:00 2001
From: Artem Pavlenko <artem@mapnik.org>
Date: Wed, 21 Mar 2012 15:47:33 +0000
Subject: [PATCH] + experimental compositing symbolizer (fill only)

---
 bindings/python/mapnik_symbolizer.cpp |  7 +++++
 include/mapnik/agg_renderer.hpp       |  4 +++
 include/mapnik/rule.hpp               | 13 ++++++---
 src/build.py                          |  2 ++
 src/load_map.cpp                      | 41 +++++++++++++++++++++++++++
 src/save_map.cpp                      |  9 ++++++
 6 files changed, 72 insertions(+), 4 deletions(-)

diff --git a/bindings/python/mapnik_symbolizer.cpp b/bindings/python/mapnik_symbolizer.cpp
index a4c4c3512..625efe7a2 100644
--- a/bindings/python/mapnik_symbolizer.cpp
+++ b/bindings/python/mapnik_symbolizer.cpp
@@ -94,6 +94,13 @@ public:
     {
         return "markers";
     }
+ 
+    template <typename Symbolizer>
+    std::string operator() ( Symbolizer const& sym)
+    {
+        boost::ignore_unused_variable_warning(sym);
+        return "unknown";
+    }
 };
 
 std::string get_symbol_type(const symbolizer& symbol)
diff --git a/include/mapnik/agg_renderer.hpp b/include/mapnik/agg_renderer.hpp
index d7e09049a..578e79f2d 100644
--- a/include/mapnik/agg_renderer.hpp
+++ b/include/mapnik/agg_renderer.hpp
@@ -97,6 +97,10 @@ public:
     void process(markers_symbolizer const& sym,
                  mapnik::feature_ptr const& feature,
                  proj_transform const& prj_trans);
+    void process(compositing_symbolizer const& sym,
+                 mapnik::feature_ptr const& feature,
+                 proj_transform const& prj_trans);
+
     inline bool process(rule::symbolizers const& /*syms*/,
                         mapnik::feature_ptr const& /*feature*/,
                         proj_transform const& /*prj_trans*/)
diff --git a/include/mapnik/rule.hpp b/include/mapnik/rule.hpp
index 23cf62a0d..2d7bdaa0a 100644
--- a/include/mapnik/rule.hpp
+++ b/include/mapnik/rule.hpp
@@ -34,6 +34,7 @@
 #include <mapnik/shield_symbolizer.hpp>
 #include <mapnik/text_symbolizer.hpp>
 #include <mapnik/markers_symbolizer.hpp>
+#include <mapnik/compositing_symbolizer.hpp>
 #include <mapnik/feature.hpp>
 #include <mapnik/expression.hpp>
 #include <mapnik/expression_string.hpp>
@@ -108,6 +109,12 @@ inline bool operator==(markers_symbolizer const& lhs,
     return (&lhs == &rhs);
 }
 
+inline bool operator==(compositing_symbolizer const& lhs,
+                       compositing_symbolizer const& rhs)
+{
+    return (&lhs == &rhs);
+}
+
 typedef boost::variant<point_symbolizer,
                        line_symbolizer,
                        line_pattern_symbolizer,
@@ -117,10 +124,8 @@ typedef boost::variant<point_symbolizer,
                        shield_symbolizer,
                        text_symbolizer,
                        building_symbolizer,
-                       markers_symbolizer> symbolizer;
-
-
-
+                       markers_symbolizer,
+                       compositing_symbolizer> symbolizer;
 
 class rule
 {
diff --git a/src/build.py b/src/build.py
index 59bf949ca..211248212 100644
--- a/src/build.py
+++ b/src/build.py
@@ -104,6 +104,7 @@ else: # Linux and others
 source = Split(
     """
     color.cpp
+    compositing_symbolizer.cpp
     conversions.cpp
     image_compositing.cpp
     box2d.cpp
@@ -251,6 +252,7 @@ source += Split(
     agg/process_raster_symbolizer.cpp
     agg/process_shield_symbolizer.cpp
     agg/process_markers_symbolizer.cpp
+    agg/process_compositing_symbolizer.cpp
     """ 
     )
 
diff --git a/src/load_map.cpp b/src/load_map.cpp
index 38bcfbff7..1ca110d77 100644
--- a/src/load_map.cpp
+++ b/src/load_map.cpp
@@ -25,6 +25,7 @@
 #include <mapnik/xml_tree.hpp>
 #include <mapnik/version.hpp>
 #include <mapnik/image_reader.hpp>
+#include <mapnik/image_compositing.hpp>
 #include <mapnik/color.hpp>
 #include <mapnik/color_factory.hpp>
 #include <mapnik/symbolizer.hpp>
@@ -107,6 +108,7 @@ private:
     void parse_shield_symbolizer(rule & rule, xml_node const& sym);
     void parse_line_symbolizer(rule & rule, xml_node const& sym);
     void parse_polygon_symbolizer(rule & rule, xml_node const& sym);
+    void parse_compositing_symbolizer(rule & rule, xml_node const& sym);
     void parse_building_symbolizer(rule & rule, xml_node const& sym);
     void parse_raster_symbolizer(rule & rule, xml_node const& sym);
     void parse_markers_symbolizer(rule & rule, xml_node const& sym);
@@ -691,6 +693,10 @@ void map_parser::parse_rule(feature_type_style & style, xml_node const& r)
             {
                 parse_polygon_pattern_symbolizer(rule, *symIter);
             }
+            else if (symIter->is("CompositingSymbolizer"))
+            {
+                parse_compositing_symbolizer(rule, *symIter);
+            }
             else if (symIter->is("TextSymbolizer"))
             {
                 parse_text_symbolizer(rule, *symIter);
@@ -1314,6 +1320,41 @@ void map_parser::parse_polygon_symbolizer(rule & rule, xml_node const & sym)
     }
 }
 
+void map_parser::parse_compositing_symbolizer(rule & rule, xml_node const & sym)
+{
+    try
+    {
+        compositing_symbolizer comp_sym;
+        // fill
+        optional<color> fill = sym.get_opt_attr<color>("fill");
+        if (fill) comp_sym.set_fill(*fill);
+        // fill-opacity
+        optional<double> opacity = sym.get_opt_attr<double>("fill-opacity");
+        if (opacity) comp_sym.set_opacity(*opacity);
+        // gamma
+        optional<double> gamma = sym.get_opt_attr<double>("gamma");
+        if (gamma)  comp_sym.set_gamma(*gamma);
+        // gamma method
+        optional<gamma_method_e> gamma_method = sym.get_opt_attr<gamma_method_e>("gamma-method");
+        if (gamma_method) comp_sym.set_gamma_method(*gamma_method);
+        // smooth value
+        optional<double> smooth = sym.get_opt_attr<double>("smooth");
+        if (smooth) comp_sym.set_smooth(*smooth);
+
+        optional<std::string> comp_op_name = sym.get_opt_attr<std::string>("comp-op");
+        if (comp_op_name)
+        {
+            composite_mode_e comp_op = comp_op_from_string(*comp_op_name);
+            comp_sym.set_comp_op(comp_op);
+        }
+        rule.append(comp_sym);
+    }
+    catch (const config_error & ex)
+    {
+        ex.append_context("in CompositingSymbolizer", sym);
+        throw;
+    }
+}
 
 void map_parser::parse_building_symbolizer(rule & rule, xml_node const & sym)
 {
diff --git a/src/save_map.cpp b/src/save_map.cpp
index 6aa9fe5d5..70c46f5b0 100644
--- a/src/save_map.cpp
+++ b/src/save_map.cpp
@@ -321,6 +321,15 @@ public:
         add_metawriter_attributes(sym_node, sym);
     }
 
+    template <typename Symbolizer>
+    void operator () ( Symbolizer const& sym)
+    {
+        // not-supported
+#ifdef MAPNIK_DEBUG
+        std::clog << typeid(sym).name() << " is not supported" << std::endl;
+#endif
+    }
+    
 private:
     serialize_symbolizer();