[core] Monitor annotation tiles, rather than completely invalidating them

Fixes #1688

4 files changed, 41 insertions, 7 deletions

diff --git a/src/mbgl/annotation/annotation_manager.cpp b/src/mbgl/annotation/annotation_manager.cpp
index e5c55c90dd..7169d51622 100644
--- a/src/mbgl/annotation/annotation_manager.cpp
+++ b/src/mbgl/annotation/annotation_manager.cpp
@@ -138,7 +138,19 @@ void AnnotationManager::updateStyle(Style& style) {
     }
 
     obsoleteShapeAnnotationLayers.clear();
-    style.getSource(SourceID)->invalidateTiles();
+
+    for (auto& monitor : monitors) {
+        monitor->update(getTile(monitor->tileID));
+    }
+}
+
+void AnnotationManager::addTileMonitor(AnnotationTileMonitor& monitor) {
+    monitors.insert(&monitor);
+    monitor.update(getTile(monitor.tileID));
+}
+
+void AnnotationManager::removeTileMonitor(AnnotationTileMonitor& monitor) {
+    monitors.erase(&monitor);
 }
 
 }
diff --git a/src/mbgl/annotation/annotation_manager.hpp b/src/mbgl/annotation/annotation_manager.hpp
index 42acbb9983..f1b41c9ccc 100644
--- a/src/mbgl/annotation/annotation_manager.hpp
+++ b/src/mbgl/annotation/annotation_manager.hpp
@@ -9,12 +9,14 @@
 
 #include <string>
 #include <vector>
+#include <set>
 
 namespace mbgl {
 
 class PointAnnotation;
 class ShapeAnnotation;
 class AnnotationTile;
+class AnnotationTileMonitor;
 class Style;
 
 class AnnotationManager : private util::noncopyable {
@@ -30,17 +32,22 @@ public:
     LatLngBounds getBoundsForAnnotations(const AnnotationIDs&) const;
 
     void updateStyle(Style&);
-    std::unique_ptr<AnnotationTile> getTile(const TileID&);
+
+    void addTileMonitor(AnnotationTileMonitor&);
+    void removeTileMonitor(AnnotationTileMonitor&);
 
     static const std::string SourceID;
     static const std::string PointLayerID;
 
 private:
+    std::unique_ptr<AnnotationTile> getTile(const TileID&);
+
     AnnotationID nextID = 0;
     PointAnnotationImpl::Tree pointTree;
     PointAnnotationImpl::Map pointAnnotations;
     ShapeAnnotationImpl::Map shapeAnnotations;
     std::vector<std::string> obsoleteShapeAnnotationLayers;
+    std::set<AnnotationTileMonitor*> monitors;
 };
 
 }
diff --git a/src/mbgl/annotation/annotation_tile.cpp b/src/mbgl/annotation/annotation_tile.cpp
index 81f7662b48..4b0f2a92ec 100644
--- a/src/mbgl/annotation/annotation_tile.cpp
+++ b/src/mbgl/annotation/annotation_tile.cpp
@@ -26,13 +26,23 @@ util::ptr<GeometryTileLayer> AnnotationTile::getLayer(const std::string& name) c
     return nullptr;
 }
 
-AnnotationTileMonitor::AnnotationTileMonitor(const TileID& id, MapData& data)
-    : tile(data.getAnnotationManager()->getTile(id)) {
+AnnotationTileMonitor::AnnotationTileMonitor(const TileID& tileID_, MapData& data_)
+    : tileID(tileID_),
+      data(data_) {
 }
 
-Request* AnnotationTileMonitor::monitorTile(std::function<void (std::exception_ptr, std::unique_ptr<GeometryTile>)> callback) {
-    callback(nullptr, std::move(tile));
+AnnotationTileMonitor::~AnnotationTileMonitor() {
+    data.getAnnotationManager()->removeTileMonitor(*this);
+}
+
+Request* AnnotationTileMonitor::monitorTile(std::function<void (std::exception_ptr, std::unique_ptr<GeometryTile>)> callback_) {
+    callback = callback_;
+    data.getAnnotationManager()->addTileMonitor(*this);
     return nullptr;
 }
 
+void AnnotationTileMonitor::update(std::unique_ptr<GeometryTile> tile) {
+    callback(nullptr, std::move(tile));
+}
+
 }
diff --git a/src/mbgl/annotation/annotation_tile.hpp b/src/mbgl/annotation/annotation_tile.hpp
index 52955da334..dcd843ed09 100644
--- a/src/mbgl/annotation/annotation_tile.hpp
+++ b/src/mbgl/annotation/annotation_tile.hpp
@@ -43,11 +43,16 @@ class MapData;
 class AnnotationTileMonitor : public GeometryTileMonitor {
 public:
     AnnotationTileMonitor(const TileID&, MapData&);
+    ~AnnotationTileMonitor();
 
+    void update(std::unique_ptr<GeometryTile>);
     Request* monitorTile(std::function<void (std::exception_ptr, std::unique_ptr<GeometryTile>)>) override;
 
+    TileID tileID;
+
 private:
-    std::unique_ptr<AnnotationTile> tile;
+    MapData& data;
+    std::function<void (std::exception_ptr, std::unique_ptr<GeometryTile>)> callback;
 };
 
 }