From a7b8ca28882dc6de2680fa6ac7ea0cbc85ad25f8 Mon Sep 17 00:00:00 2001
From: Blake Thompson <flippmoke@gmail.com>
Date: Fri, 16 Jan 2015 15:36:53 -0600
Subject: [PATCH] Moved set_rectangle out of image_32 into image_util.

Ref #2633
---
 include/mapnik/graphics.hpp   | 24 ----------
 include/mapnik/image_util.hpp |  3 ++
 src/image_util.cpp            | 84 +++++++++++++++++++++++++++++++++++
 3 files changed, 87 insertions(+), 24 deletions(-)

diff --git a/include/mapnik/graphics.hpp b/include/mapnik/graphics.hpp
index dccbdaeea..6faae9927 100644
--- a/include/mapnik/graphics.hpp
+++ b/include/mapnik/graphics.hpp
@@ -117,30 +117,6 @@ public:
         return data_.height();
     }
 
-    inline void set_rectangle(int x0,int y0,image_data_rgba8 const& data)
-    {
-        box2d<int> ext0(0,0,data_.width(),data_.height());
-        box2d<int> ext1(x0,y0,x0+data.width(),y0+data.height());
-
-        if (ext0.intersects(ext1))
-        {
-            box2d<int> box = ext0.intersect(ext1);
-            for (int y = box.miny(); y < box.maxy(); ++y)
-            {
-                unsigned int* row_to =  data_.getRow(y);
-                unsigned int const * row_from = data.getRow(y-y0);
-
-                for (int x = box.minx(); x < box.maxx(); ++x)
-                {
-                    if (row_from[x-x0] & 0xff000000)
-                    {
-                        row_to[x] = row_from[x-x0];
-                    }
-                }
-            }
-        }
-    }
-
     template <typename MergeMethod>
         inline void merge_rectangle(image_data_rgba8 const& data, unsigned x0, unsigned y0, float opacity)
     {
diff --git a/include/mapnik/image_util.hpp b/include/mapnik/image_util.hpp
index c96e879cc..8b7f1e0c2 100644
--- a/include/mapnik/image_util.hpp
+++ b/include/mapnik/image_util.hpp
@@ -135,6 +135,9 @@ MAPNIK_DECL void set_color_to_alpha (T & image, color const& c);
 template <typename T1, typename T2>
 MAPNIK_DECL void fill (T1 & data, T2 const& c);
 
+template <typename T>
+MAPNIK_DECL void set_rectangle (T & dst, T const& src, int x = 0, int y = 0);
+
 inline bool is_png(std::string const& filename)
 {
     return boost::algorithm::iends_with(filename,std::string(".png"));
diff --git a/src/image_util.cpp b/src/image_util.cpp
index 3da3c7fc2..761d2f2cf 100644
--- a/src/image_util.cpp
+++ b/src/image_util.cpp
@@ -863,4 +863,88 @@ MAPNIK_DECL void fill<image_data_rgba8, int32_t> (image_data_rgba8 & data , int3
     visitor(data);
 }
 
+namespace detail {
+
+struct visitor_set_rectangle
+{
+    visitor_set_rectangle(image_data_any const & src, int x0, int y0)
+        : src_(src), x0_(x0), y0_(y0) {}
+
+    template <typename T>
+    void operator() (T & dst)
+    {
+        using pixel_type = typename T::pixel_type;
+        T src = util::get<T>(src_);
+        box2d<int> ext0(0,0,dst.width(),dst.height());
+        box2d<int> ext1(x0_,y0_,x0_+src.width(),y0_+src.height());
+
+        if (ext0.intersects(ext1))
+        {
+            box2d<int> box = ext0.intersect(ext1);
+            for (std::size_t y = box.miny(); y < box.maxy(); ++y)
+            {
+                pixel_type* row_to =  dst.getRow(y);
+                pixel_type const * row_from = src.getRow(y-y0_);
+
+                for (std::size_t x = box.minx(); x < box.maxx(); ++x)
+                {
+                    row_to[x] = row_from[x-x0_];
+                }
+            }
+        }
+    }
+  private:
+    image_data_any const& src_;
+    int x0_;
+    int y0_;
+};
+
+template <>
+void visitor_set_rectangle::operator()<image_data_rgba8> (image_data_rgba8 & dst)
+{
+    using pixel_type = typename image_data_rgba8::pixel_type;
+    image_data_rgba8 src = util::get<image_data_rgba8>(src_);
+    box2d<int> ext0(0,0,dst.width(),dst.height());
+    box2d<int> ext1(x0_,y0_,x0_+src.width(),y0_+src.height());
+
+    if (ext0.intersects(ext1))
+    {
+        box2d<int> box = ext0.intersect(ext1);
+        for (std::size_t y = box.miny(); y < box.maxy(); ++y)
+        {
+            pixel_type* row_to =  dst.getRow(y);
+            pixel_type const * row_from = src.getRow(y-y0_);
+
+            for (std::size_t x = box.minx(); x < box.maxx(); ++x)
+            {
+                if (row_from[x-x0_] & 0xff000000) // Don't change if alpha == 0
+                {
+                    row_to[x] = row_from[x-x0_];
+                }
+            }
+        }
+    }
+}
+
+template<>
+void visitor_set_rectangle::operator()<image_data_null> (image_data_null &)
+{
+    throw std::runtime_error("Set rectangle not support for null images");
+}
+
+} // end detail ns 
+
+template <typename T>
+void set_rectangle (T & dst, T const& src, int x, int y)
+{
+    detail::visitor_set_rectangle visit(src, x, y);
+    visit(dst);
+}
+
+template <>
+void set_rectangle<image_data_any> (image_data_any & dst, image_data_any const& src, int x, int y)
+{
+    util::apply_visitor(detail::visitor_set_rectangle(src, x, y), dst);
+}
+
 } // end ns