Allow using tileSize: 512 as a switch to trade retina support for 512px raster tiles

5 files changed, 16 insertions, 11 deletions

diff --git a/src/mbgl/map/source.cpp b/src/mbgl/map/source.cpp
index 1a7933f53e..96af8c3cba 100644
--- a/src/mbgl/map/source.cpp
+++ b/src/mbgl/map/source.cpp
@@ -104,7 +104,7 @@ void Source::load() {
                 // from the stylesheet. Then merge in the values parsed from the TileJSON we retrieved
                 // via the URL.
                 try {
-                    newInfo = StyleParser::parseTileJSON(*res.data, url, type);
+                    newInfo = StyleParser::parseTileJSON(*res.data, url, type, tileSize);
                 } catch (...) {
                     observer->onSourceError(*this, std::current_exception());
                     return;
diff --git a/src/mbgl/style/style_parser.cpp b/src/mbgl/style/style_parser.cpp
index 50276c8f5b..7c2a94b206 100644
--- a/src/mbgl/style/style_parser.cpp
+++ b/src/mbgl/style/style_parser.cpp
@@ -256,7 +256,7 @@ std::unique_ptr<mapbox::geojsonvt::GeoJSONVT> StyleParser::parseGeoJSON(const JS
     }
 }
 
-std::unique_ptr<SourceInfo> StyleParser::parseTileJSON(const std::string& json, const std::string& sourceURL, SourceType type) {
+std::unique_ptr<SourceInfo> StyleParser::parseTileJSON(const std::string& json, const std::string& sourceURL, SourceType type, uint16_t tileSize) {
     rapidjson::GenericDocument<rapidjson::UTF8<>, rapidjson::CrtAllocator> document;
     document.Parse<0>(json.c_str());
 
@@ -270,10 +270,9 @@ std::unique_ptr<SourceInfo> StyleParser::parseTileJSON(const std::string& json,
 
     // TODO: Remove this hack by delivering proper URLs in the TileJSON to begin with.
     if (util::mapbox::isMapboxURL(sourceURL)) {
-        std::transform(result->tiles.begin(),
-                       result->tiles.end(),
-                       result->tiles.begin(),
-                       std::bind(util::mapbox::canonicalizeTileURL, std::placeholders::_1, type));
+        for (auto& url : result->tiles) {
+            url = util::mapbox::canonicalizeTileURL(url, type, tileSize);
+        }
     }
 
     return result;
diff --git a/src/mbgl/style/style_parser.hpp b/src/mbgl/style/style_parser.hpp
index 162a10c87c..6b7c3fefbb 100644
--- a/src/mbgl/style/style_parser.hpp
+++ b/src/mbgl/style/style_parser.hpp
@@ -31,7 +31,7 @@ public:
     // Statically evaluate layer properties to determine what font stacks are used.
     std::vector<std::string> fontStacks() const;
 
-    static std::unique_ptr<SourceInfo> parseTileJSON(const std::string& json, const std::string& sourceURL, SourceType);
+    static std::unique_ptr<SourceInfo> parseTileJSON(const std::string& json, const std::string& sourceURL, SourceType, uint16_t tileSize);
     static std::unique_ptr<SourceInfo> parseTileJSON(const JSValue&);
 
     static std::unique_ptr<mapbox::geojsonvt::GeoJSONVT> parseGeoJSON(const JSValue&);
diff --git a/src/mbgl/util/mapbox.cpp b/src/mbgl/util/mapbox.cpp
index 93b2b8521c..7ee0f279b6 100644
--- a/src/mbgl/util/mapbox.cpp
+++ b/src/mbgl/util/mapbox.cpp
@@ -119,7 +119,7 @@ std::string normalizeTileURL(const std::string& url, const std::string& accessTo
     return baseURL + "v4/" + url.substr(sizeof("mapbox://tiles/") - 1) + "?access_token=" + accessToken;
 }
 
-std::string canonicalizeTileURL(const std::string& url, SourceType type) {
+std::string canonicalizeTileURL(const std::string& url, SourceType type, uint16_t tileSize) {
     auto tilesetStartIdx = url.find("/v4/");
     if (tilesetStartIdx == std::string::npos) {
         return url;
@@ -159,8 +159,14 @@ std::string canonicalizeTileURL(const std::string& url, SourceType type) {
     }
 #endif // !defined(__ANDROID__) && !defined(__APPLE__)
 
-    return "mapbox://tiles/" + tileset + "/{z}/{x}/{y}" +
-        (type == SourceType::Raster ? "{ratio}" : "") + "." + extension;
+    std::string result = "mapbox://tiles/" + tileset + "/{z}/{x}/{y}";
+
+    if (type == SourceType::Raster) {
+        result += tileSize == 512 ? "@2x" : "{ratio}";
+    }
+
+    result += "." + extension;
+    return result;
 }
 
 } // end namespace mapbox
diff --git a/src/mbgl/util/mapbox.hpp b/src/mbgl/util/mapbox.hpp
index c03916ff63..bb0536cfa2 100644
--- a/src/mbgl/util/mapbox.hpp
+++ b/src/mbgl/util/mapbox.hpp
@@ -17,7 +17,7 @@ std::string normalizeGlyphsURL(const std::string& url, const std::string& access
 std::string normalizeTileURL(const std::string& url, const std::string& accessToken);
 
 // Return a "mapbox://tiles/..." URL (suitable for normalizeTileURL) for the given Mapbox tile URL.
-std::string canonicalizeTileURL(const std::string& url, SourceType);
+std::string canonicalizeTileURL(const std::string& url, SourceType, uint16_t tileSize);
 
 } // namespace mapbox
 } // namespace util