Emit the signal on the MapThread

We were previously emitting the signal on the thread parsing the
glyph, but signals can only be trigger from the MapThread
because the observers are living there.

3 files changed, 19 insertions, 5 deletions

diff --git a/src/mbgl/map/map_context.cpp b/src/mbgl/map/map_context.cpp
index 5191293a08..f373274ebd 100644
--- a/src/mbgl/map/map_context.cpp
+++ b/src/mbgl/map/map_context.cpp
@@ -36,7 +36,7 @@ MapContext::MapContext(uv_loop_t* loop, View& view_, FileSource& fileSource, Map
       envScope(env, ThreadType::Map, "Map"),
       updated(static_cast<UpdateType>(Update::Nothing)),
       asyncUpdate(util::make_unique<uv::async>(loop, [this] { update(); })),
-      glyphStore(util::make_unique<GlyphStore>(env)),
+      glyphStore(util::make_unique<GlyphStore>(loop, env)),
       glyphAtlas(util::make_unique<GlyphAtlas>(1024, 1024)),
       spriteAtlas(util::make_unique<SpriteAtlas>(512, 512)),
       lineAtlas(util::make_unique<LineAtlas>(512, 512)),
diff --git a/src/mbgl/text/glyph_store.cpp b/src/mbgl/text/glyph_store.cpp
index 71c1be6d95..8531912185 100644
--- a/src/mbgl/text/glyph_store.cpp
+++ b/src/mbgl/text/glyph_store.cpp
@@ -9,6 +9,7 @@
 #include <mbgl/util/constants.hpp>
 #include <mbgl/util/token.hpp>
 #include <mbgl/util/math.hpp>
+#include <mbgl/util/uv_detail.hpp>
 #include <mbgl/storage/file_source.hpp>
 #include <mbgl/platform/log.hpp>
 #include <mbgl/platform/platform.hpp>
@@ -236,8 +237,11 @@ bool GlyphPBF::isParsed() const {
     return parsed;
 }
 
-GlyphStore::GlyphStore(Environment& env_)
-    : env(env_), observer(nullptr) {
+GlyphStore::GlyphStore(uv_loop_t* loop, Environment& env_)
+    : env(env_),
+      asyncEmitGlyphRangeLoaded(util::make_unique<uv::async>(loop, [this] { emitGlyphRangeLoaded(); })),
+      observer(nullptr) {
+    asyncEmitGlyphRangeLoaded->unref();
 }
 
 GlyphStore::~GlyphStore() {
@@ -258,7 +262,7 @@ bool GlyphStore::requestGlyphRangesIfNeeded(const std::string& fontStack,
 
     auto callback = [this, fontStack](GlyphPBF* glyph) {
         glyph->parse(*createFontStack(fontStack));
-        emitGlyphRangeLoaded();
+        asyncEmitGlyphRangeLoaded->send();
     };
 
     std::lock_guard<std::mutex> lock(rangesMutex);
diff --git a/src/mbgl/text/glyph_store.hpp b/src/mbgl/text/glyph_store.hpp
index a41eec5330..efa848dd08 100644
--- a/src/mbgl/text/glyph_store.hpp
+++ b/src/mbgl/text/glyph_store.hpp
@@ -13,6 +13,14 @@
 #include <string>
 #include <unordered_map>
 
+typedef struct uv_loop_s uv_loop_t;
+
+namespace uv {
+
+class async;
+
+}
+
 namespace mbgl {
 
 class FileSource;
@@ -87,7 +95,7 @@ public:
         virtual void onGlyphRangeLoaded() = 0;
     };
 
-    GlyphStore(Environment &);
+    GlyphStore(uv_loop_t* loop, Environment &);
     ~GlyphStore();
 
     // Asynchronously request for GlyphRanges and when it gets loaded, notifies the
@@ -116,6 +124,8 @@ private:
     std::unordered_map<std::string, std::unique_ptr<FontStack>> stacks;
     std::mutex stacksMutex;
 
+    std::unique_ptr<uv::async> asyncEmitGlyphRangeLoaded;
+
     Observer* observer;
 };