Keep a pointer to GlyphStore on ResourceLoader

For now, keep a pointer so we can subscribe/unsubscribe to events. In
the future, we should move this object completely to ResourceLoader, but
we can't do it now because we delete the ResourceLoader when changing
the style.

src/mbgl/map/map_context.cpp

@@ -134,6 +134,7 @@ void MapContext::loadStyleJSON(const std::string& json, const std::string& base)
     resourceLoader->setAccessToken(data.getAccessToken());
     resourceLoader->setObserver(this);
     resourceLoader->setStyle(style.get());
+    resourceLoader->setGlyphStore(glyphStore.get());
 
     triggerUpdate(Update::Zoom);
 }
@@ -141,8 +142,7 @@ void MapContext::loadStyleJSON(const std::string& json, const std::string& base)
 void MapContext::updateTiles() {
     assert(Environment::currentlyOn(ThreadType::Map));
 
-    resourceLoader->update(data, transformState, *glyphAtlas, *glyphStore,
-                           *spriteAtlas, *texturePool);
+    resourceLoader->update(data, transformState, *glyphAtlas, *spriteAtlas, *texturePool);
 }
 
 void MapContext::updateAnnotationTiles(const std::vector<TileID>& ids) {

src/mbgl/map/resource_loader.cpp

@@ -25,6 +25,10 @@ ResourceLoader::~ResourceLoader() {
     if (sprite_) {
         sprite_->setObserver(nullptr);
     }
+
+    if (glyphStore_) {
+        glyphStore_->setObserver(nullptr);
+    }
 }
 
 void ResourceLoader::setObserver(Observer* observer) {
@@ -45,6 +49,18 @@ void ResourceLoader::setStyle(Style* style) {
     }
 }
 
+void ResourceLoader::setGlyphStore(GlyphStore* glyphStore) {
+    assert(glyphStore);
+
+    if (glyphStore_) {
+        glyphStore_->setObserver(nullptr);
+    }
+
+    glyphStore_ = glyphStore;
+    glyphStore_->setObserver(this);
+}
+
+
 void ResourceLoader::setAccessToken(const std::string& accessToken) {
     accessToken_ = accessToken;
 }
@@ -52,7 +68,6 @@ void ResourceLoader::setAccessToken(const std::string& accessToken) {
 void ResourceLoader::update(MapData& data,
                             const TransformState& transform,
                             GlyphAtlas& glyphAtlas,
-                            GlyphStore& glyphStore,
                             SpriteAtlas& spriteAtlas,
                             TexturePool& texturePool) {
     if (!style_) {
@@ -69,8 +84,8 @@ void ResourceLoader::update(MapData& data,
     }
 
     for (const auto& source : style_->sources) {
-        source->update(
-            data, transform, *style_, glyphAtlas, glyphStore, spriteAtlas, sprite_, texturePool);
+        source->update(data, transform, *style_, glyphAtlas, *glyphStore_,
+                       spriteAtlas, sprite_, texturePool);
     }
 }
 

src/mbgl/map/resource_loader.hpp

@@ -43,13 +43,17 @@ public:
     // a new style we will go through all of them and try to load.
     void setStyle(Style* style);
 
+    // TODO: Move GlyphStore to ResourceLoader. We cannot do it now
+    // because we reset the ResourceLoader every time we change the
+    // style.
+    void setGlyphStore(GlyphStore* glyphStore);
+
     // Set the access token to be used for loading the tile data.
     void setAccessToken(const std::string& accessToken);
 
     // Fetch the tiles needed by the current viewport and emit a signal when
     // a tile is ready so observers can render the tile.
-    void update(MapData&, const TransformState&, GlyphAtlas&, GlyphStore&,
-                SpriteAtlas&, TexturePool&);
+    void update(MapData&, const TransformState&, GlyphAtlas&, SpriteAtlas&, TexturePool&);
 
     // FIXME: There is probably a better place for this.
     inline util::ptr<Sprite> getSprite() const {
@@ -71,7 +75,10 @@ private:
 
     std::string accessToken_;
     util::ptr<Sprite> sprite_;
+
+    GlyphStore* glyphStore_ = nullptr;
     Style* style_ = nullptr;
+
     Observer* observer_ = nullptr;
 };