From dcd21e75d9a64c577422a4d6ef69aebfbdb7b456 Mon Sep 17 00:00:00 2001
From: Dane Springmeyer <dane@mapbox.com>
Date: Fri, 12 Sep 2014 15:50:00 -0700
Subject: [PATCH] be able to pass down scale_factor to python grid renderering

---
 bindings/python/mapnik_python.cpp     | 24 ++++++++++++++++++++----
 bindings/python/python_grid_utils.cpp | 14 ++++++--------
 bindings/python/python_grid_utils.hpp | 10 ++++------
 3 files changed, 30 insertions(+), 18 deletions(-)

diff --git a/bindings/python/mapnik_python.cpp b/bindings/python/mapnik_python.cpp
index 278e7b611..4dd1161df 100644
--- a/bindings/python/mapnik_python.cpp
+++ b/bindings/python/mapnik_python.cpp
@@ -220,7 +220,10 @@ void render_with_detector(
 
 void render_layer2(mapnik::Map const& map,
                    mapnik::image_32& image,
-                   unsigned layer_idx)
+                   unsigned layer_idx,
+                   double scale_factor,
+                   unsigned offset_x,
+                   unsigned offset_y)
 {
     std::vector<mapnik::layer> const& layers = map.layers();
     std::size_t layer_num = layers.size();
@@ -233,7 +236,7 @@ void render_layer2(mapnik::Map const& map,
 
     python_unblock_auto_block b;
     mapnik::layer const& layer = layers[layer_idx];
-    mapnik::agg_renderer<mapnik::image_32> ren(map,image,1.0,0,0);
+    mapnik::agg_renderer<mapnik::image_32> ren(map,image,scale_factor,offset_x,offset_y);
     std::set<std::string> names;
     ren.apply(layer,names);
 }
@@ -730,12 +733,25 @@ BOOST_PYTHON_MODULE(_mapnik)
             ));
 
     def("render_layer", &render_layer2,
-        (arg("map"),arg("image"),args("layer"))
+        (arg("map"),
+         arg("image"),
+         arg("layer"),
+         arg("scale_factor")=1.0,
+         arg("offset_x")=0,
+         arg("offset_y")=0
+        )
         );
 
 #if defined(GRID_RENDERER)
     def("render_layer", &mapnik::render_layer_for_grid,
-        (arg("map"),arg("grid"),args("layer"),arg("fields")=boost::python::list())
+        (arg("map"),
+         arg("grid"),
+         arg("layer"),
+         arg("fields")=boost::python::list(),
+         arg("scale_factor")=1.0,
+         arg("offset_x")=0,
+         arg("offset_y")=0
+        )
         );
 #endif
 
diff --git a/bindings/python/python_grid_utils.cpp b/bindings/python/python_grid_utils.cpp
index 1b36b1340..13ac5d493 100644
--- a/bindings/python/python_grid_utils.cpp
+++ b/bindings/python/python_grid_utils.cpp
@@ -339,15 +339,13 @@ boost::python::dict grid_encode( T const& grid, std::string const& format, bool
 template boost::python::dict grid_encode( mapnik::grid const& grid, std::string const& format, bool add_features, unsigned int resolution);
 template boost::python::dict grid_encode( mapnik::grid_view const& grid, std::string const& format, bool add_features, unsigned int resolution);
 
-/* new approach: key comes from grid object
- * grid size should be same as the map
- * encoding, resizing handled as method on grid object
- * whether features are dumped is determined by argument not 'fields'
- */
 void render_layer_for_grid(mapnik::Map const& map,
                                   mapnik::grid & grid,
-                                  unsigned layer_idx, // TODO - layer by name or index
-                                  boost::python::list const& fields)
+                                  unsigned layer_idx,
+                                  boost::python::list const& fields,
+                                  double scale_factor,
+                                  unsigned offset_x,
+                                  unsigned offset_y)
 {
     std::vector<mapnik::layer> const& layers = map.layers();
     std::size_t layer_num = layers.size();
@@ -390,7 +388,7 @@ void render_layer_for_grid(mapnik::Map const& map,
         attributes.insert(join_field);
     }
 
-    mapnik::grid_renderer<mapnik::grid> ren(map,grid,1.0,0,0);
+    mapnik::grid_renderer<mapnik::grid> ren(map,grid,scale_factor,offset_x,offset_y);
     mapnik::layer const& layer = layers[layer_idx];
     ren.apply(layer,attributes);
 }
diff --git a/bindings/python/python_grid_utils.hpp b/bindings/python/python_grid_utils.hpp
index 86d076869..f6089449f 100644
--- a/bindings/python/python_grid_utils.hpp
+++ b/bindings/python/python_grid_utils.hpp
@@ -66,15 +66,13 @@ void grid_encode_utf(T const& grid_type,
 template <typename T>
 boost::python::dict grid_encode( T const& grid, std::string const& format, bool add_features, unsigned int resolution);
 
-/* new approach: key comes from grid object
- * grid size should be same as the map
- * encoding, resizing handled as method on grid object
- * whether features are dumped is determined by argument not 'fields'
- */
 void render_layer_for_grid(const mapnik::Map& map,
                            mapnik::grid& grid,
                            unsigned layer_idx, // TODO - layer by name or index
-                           boost::python::list const& fields);
+                           boost::python::list const& fields,
+                           double scale_factor,
+                           unsigned offset_x,
+                           unsigned offset_y);
 
 }