From 0efb6964efd973bf048cc6007be8fde7596b9adb Mon Sep 17 00:00:00 2001
From: Dane Springmeyer <dane@mapbox.com>
Date: Wed, 1 Oct 2014 20:59:05 -0700
Subject: [PATCH] per map load cache if a fonts is known as valid

---
 src/load_map.cpp | 56 ++++++++++++++++++++++++++++++++++--------------
 1 file changed, 40 insertions(+), 16 deletions(-)

diff --git a/src/load_map.cpp b/src/load_map.cpp
index a73d8eb16..a87f37e00 100644
--- a/src/load_map.cpp
+++ b/src/load_map.cpp
@@ -89,6 +89,9 @@ public:
         filename_(filename),
         font_library_(),
         font_file_mapping_(map.get_font_file_mapping()),
+        font_name_cache_(),
+        file_sources_(),
+        fontsets_(),
         xml_base_path_() {}
 
     void parse_map(Map & map, xml_node const& node, std::string const& base_path);
@@ -131,6 +134,7 @@ private:
     std::map<std::string,parameters> datasource_templates_;
     font_library font_library_;
     freetype_engine::font_file_mapping_type & font_file_mapping_;
+    std::map<std::string,bool> font_name_cache_;
     std::map<std::string,std::string> file_sources_;
     std::map<std::string,font_set> fontsets_;
     std::string xml_base_path_;
@@ -512,24 +516,34 @@ void map_parser::parse_fontset(Map & map, xml_node const& node)
     }
 }
 
-bool map_parser::parse_font(font_set &fset, xml_node const& f)
+bool map_parser::parse_font(font_set & fset, xml_node const& f)
 {
-    optional<std::string> face_name = f.get_opt_attr<std::string>("face-name");
-    if (face_name)
+    optional<std::string> has_face_name = f.get_opt_attr<std::string>("face-name");
+    if (has_face_name)
     {
-        // TODO - cache results to avoid repeated opens
-        if (freetype_engine::can_open(*face_name,
-                                      font_library_,
-                                      font_file_mapping_,
-                                      freetype_engine::get_mapping()))
+        std::string face_name = *has_face_name;
+        bool found = false;
+        auto itr = font_name_cache_.find(face_name);
+        if (itr != font_name_cache_.end())
         {
-            fset.add_face_name(*face_name);
+            found = itr->second;
+        }
+        else
+        {
+            found = freetype_engine::can_open(face_name,
+                                          font_library_,
+                                          font_file_mapping_,
+                                          freetype_engine::get_mapping());
+            font_name_cache_.emplace(face_name,found);
+        }
+        if (found)
+        {
+            fset.add_face_name(face_name);
             return true;
         }
         else if (strict_)
         {
-            throw config_error("Failed to find font face '" +
-                               *face_name + "'");
+            throw config_error("Failed to find font face '" + face_name + "'");
         }
     }
     else
@@ -1523,11 +1537,21 @@ void map_parser::parse_pair_layout(group_symbolizer_properties & prop, xml_node
 
 void map_parser::ensure_font_face(std::string const& face_name)
 {
-    // TODO - cache results to avoid repeated opens
-    if (!freetype_engine::can_open(face_name,
-                                  font_library_,
-                                  font_file_mapping_,
-                                  freetype_engine::get_mapping()))
+    bool found = false;
+    auto itr = font_name_cache_.find(face_name);
+    if (itr != font_name_cache_.end())
+    {
+        found = itr->second;
+    }
+    else
+    {
+        found = freetype_engine::can_open(face_name,
+                                      font_library_,
+                                      font_file_mapping_,
+                                      freetype_engine::get_mapping());
+        font_name_cache_.emplace(face_name,found);
+    }
+    if (!found)
     {
         throw config_error("Failed to find font face '" +
                            face_name + "'");