[core] move *Observers to their own files

16 files changed, 139 insertions, 75 deletions

diff --git a/src/mbgl/annotation/annotation_manager.cpp b/src/mbgl/annotation/annotation_manager.cpp
index 329f1e3c3f..1febc757a4 100644
--- a/src/mbgl/annotation/annotation_manager.cpp
+++ b/src/mbgl/annotation/annotation_manager.cpp
@@ -1,5 +1,6 @@
 #include <mbgl/annotation/annotation_manager.hpp>
 #include <mbgl/annotation/annotation_tile.hpp>
+#include <mbgl/source/source.hpp>
 #include <mbgl/style/style.hpp>
 #include <mbgl/layer/symbol_layer.hpp>
 
diff --git a/src/mbgl/map/map.cpp b/src/mbgl/map/map.cpp
index fc2a653510..51e8caa295 100644
--- a/src/mbgl/map/map.cpp
+++ b/src/mbgl/map/map.cpp
@@ -7,6 +7,7 @@
 #include <mbgl/annotation/shape_annotation.hpp>
 #include <mbgl/annotation/annotation_manager.hpp>
 #include <mbgl/style/style.hpp>
+#include <mbgl/style/style_observer.hpp>
 #include <mbgl/style/style_layer.hpp>
 #include <mbgl/style/property_transition.hpp>
 #include <mbgl/style/style_update_parameters.hpp>
@@ -33,7 +34,7 @@ enum class RenderState {
     fully
 };
 
-class Map::Impl : public Style::Observer {
+class Map::Impl : public StyleObserver {
 public:
     Impl(View&, FileSource&, MapMode, GLContextMode, ConstrainMode, ViewportMode);
 
diff --git a/src/mbgl/source/source.cpp b/src/mbgl/source/source.cpp
index b4f9def3d4..ac05963ce0 100644
--- a/src/mbgl/source/source.cpp
+++ b/src/mbgl/source/source.cpp
@@ -1,4 +1,5 @@
 #include <mbgl/source/source.hpp>
+#include <mbgl/source/source_observer.hpp>
 #include <mbgl/map/transform.hpp>
 #include <mbgl/tile/tile.hpp>
 #include <mbgl/tile/vector_tile.hpp>
@@ -39,6 +40,8 @@
 
 namespace mbgl {
 
+static SourceObserver nullObserver;
+
 Source::Source(SourceType type_,
                const std::string& id_,
                const std::string& url_,
@@ -50,7 +53,8 @@ Source::Source(SourceType type_,
       url(url_),
       tileSize(tileSize_),
       info(std::move(info_)),
-      geojsonvt(std::move(geojsonvt_)) {
+      geojsonvt(std::move(geojsonvt_)),
+      observer(&nullObserver) {
 }
 
 Source::~Source() = default;
@@ -380,7 +384,7 @@ void Source::onLowMemory() {
     cache.clear();
 }
 
-void Source::setObserver(Observer* observer_) {
+void Source::setObserver(SourceObserver* observer_) {
     observer = observer_;
 }
 
diff --git a/src/mbgl/source/source.hpp b/src/mbgl/source/source.hpp
index 8bed717780..4da653d9a4 100644
--- a/src/mbgl/source/source.hpp
+++ b/src/mbgl/source/source.hpp
@@ -32,21 +32,10 @@ class AsyncRequest;
 class TransformState;
 class Tile;
 struct ClipID;
+class SourceObserver;
 
 class Source : private util::noncopyable {
 public:
-    class Observer {
-    public:
-        virtual ~Observer() = default;
-
-        virtual void onSourceLoaded(Source&) {};
-        virtual void onSourceError(Source&, std::exception_ptr) {};
-
-        virtual void onTileLoaded(Source&, const OverscaledTileID&, bool /* isNewTile */) {};
-        virtual void onTileError(Source&, const OverscaledTileID&, std::exception_ptr) {};
-        virtual void onPlacementRedone() {};
-    };
-
     Source(SourceType,
            const std::string& id,
            const std::string& url,
@@ -86,7 +75,7 @@ public:
     void setCacheSize(size_t);
     void onLowMemory();
 
-    void setObserver(Observer* observer);
+    void setObserver(SourceObserver* observer);
     void dumpDebugLogs() const;
 
     const SourceType type;
@@ -115,8 +104,7 @@ private:
 
     std::unique_ptr<AsyncRequest> req;
 
-    Observer nullObserver;
-    Observer* observer = &nullObserver;
+    SourceObserver* observer = nullptr;
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/source/source_observer.hpp b/src/mbgl/source/source_observer.hpp
new file mode 100644
index 0000000000..82d5a88729
--- /dev/null
+++ b/src/mbgl/source/source_observer.hpp
@@ -0,0 +1,24 @@
+#ifndef MBGL_MAP_SOURCE_OBSERVER
+#define MBGL_MAP_SOURCE_OBSERVER
+
+#include <exception>
+
+namespace mbgl {
+
+class Source;
+class OverscaledTileID;
+
+class SourceObserver {
+public:
+    virtual ~SourceObserver() = default;
+
+    virtual void onSourceLoaded(Source&) {}
+    virtual void onSourceError(Source&, std::exception_ptr) {}
+    virtual void onTileLoaded(Source&, const OverscaledTileID&, bool /* isNewTile */) {}
+    virtual void onTileError(Source&, const OverscaledTileID&, std::exception_ptr) {}
+    virtual void onPlacementRedone() {}
+};
+
+} // namespace mbgl
+
+#endif
diff --git a/src/mbgl/sprite/sprite_store.cpp b/src/mbgl/sprite/sprite_store.cpp
index ae8835534a..b9249a3ffc 100644
--- a/src/mbgl/sprite/sprite_store.cpp
+++ b/src/mbgl/sprite/sprite_store.cpp
@@ -1,4 +1,5 @@
 #include <mbgl/sprite/sprite_store.hpp>
+#include <mbgl/sprite/sprite_store_observer.hpp>
 #include <mbgl/sprite/sprite_parser.hpp>
 #include <mbgl/platform/log.hpp>
 #include <mbgl/storage/file_source.hpp>
@@ -11,6 +12,8 @@
 
 namespace mbgl {
 
+static SpriteStoreObserver nullObserver;
+
 struct SpriteStore::Loader {
     std::shared_ptr<const std::string> image;
     std::shared_ptr<const std::string> json;
@@ -19,7 +22,7 @@ struct SpriteStore::Loader {
 };
 
 SpriteStore::SpriteStore(float pixelRatio_)
-    : pixelRatio(pixelRatio_ > 1 ? 2 : 1) {
+    : pixelRatio(pixelRatio_ > 1 ? 2 : 1), observer(&nullObserver) {
 }
 
 SpriteStore::~SpriteStore() = default;
@@ -80,7 +83,7 @@ void SpriteStore::emitSpriteLoadedIfComplete() {
     }
 }
 
-void SpriteStore::setObserver(Observer* observer_) {
+void SpriteStore::setObserver(SpriteStoreObserver* observer_) {
     observer = observer_;
 }
 
diff --git a/src/mbgl/sprite/sprite_store.hpp b/src/mbgl/sprite/sprite_store.hpp
index 995cb81900..50f74e174d 100644
--- a/src/mbgl/sprite/sprite_store.hpp
+++ b/src/mbgl/sprite/sprite_store.hpp
@@ -11,19 +11,12 @@
 namespace mbgl {
 
 class FileSource;
+class SpriteStoreObserver;
 
 class SpriteStore : private util::noncopyable {
 public:
     using Sprites = std::map<std::string, std::shared_ptr<const SpriteImage>>;
 
-    class Observer {
-    public:
-        virtual ~Observer() = default;
-
-        virtual void onSpriteLoaded() {};
-        virtual void onSpriteError(std::exception_ptr) {};
-    };
-
     SpriteStore(float pixelRatio);
     ~SpriteStore();
 
@@ -35,7 +28,7 @@ public:
 
     void dumpDebugLogs() const;
 
-    void setObserver(Observer* observer);
+    void setObserver(SpriteStoreObserver* observer);
 
     // Adds/replaces a Sprite image.
     void setSprite(const std::string&, std::shared_ptr<const SpriteImage> = nullptr);
@@ -63,8 +56,7 @@ private:
 
     bool loaded = false;
 
-    Observer nullObserver;
-    Observer* observer = &nullObserver;
+    SpriteStoreObserver* observer = nullptr;
 
     // Lock for sprites and dirty maps.
     std::mutex mutex;
diff --git a/src/mbgl/sprite/sprite_store_observer.hpp b/src/mbgl/sprite/sprite_store_observer.hpp
new file mode 100644
index 0000000000..66d9d3790f
--- /dev/null
+++ b/src/mbgl/sprite/sprite_store_observer.hpp
@@ -0,0 +1,18 @@
+#ifndef MBGL_SPRITE_STORE_OBSERVER
+#define MBGL_SPRITE_STORE_OBSERVER
+
+#include <exception>
+
+namespace mbgl {
+
+class SpriteStoreObserver {
+public:
+    virtual ~SpriteStoreObserver() = default;
+
+    virtual void onSpriteLoaded() {}
+    virtual void onSpriteError(std::exception_ptr) {}
+};
+
+} // namespace mbgl
+
+#endif
diff --git a/src/mbgl/style/style.cpp b/src/mbgl/style/style.cpp
index 88c08f1d20..c77d1b5a52 100644
--- a/src/mbgl/style/style.cpp
+++ b/src/mbgl/style/style.cpp
@@ -1,4 +1,5 @@
 #include <mbgl/style/style.hpp>
+#include <mbgl/style/style_observer.hpp>
 #include <mbgl/source/source.hpp>
 #include <mbgl/tile/tile.hpp>
 #include <mbgl/map/transform_state.hpp>
@@ -27,6 +28,8 @@
 
 namespace mbgl {
 
+static StyleObserver nullObserver;
+
 bool Style::addClass(const std::string& className, const PropertyTransition& properties) {
     if (std::find(classes.begin(), classes.end(), className) != classes.end()) return false;
     classes.push_back(className);
@@ -64,6 +67,7 @@ Style::Style(FileSource& fileSource_, float pixelRatio)
       spriteStore(std::make_unique<SpriteStore>(pixelRatio)),
       spriteAtlas(std::make_unique<SpriteAtlas>(1024, 1024, pixelRatio, *spriteStore)),
       lineAtlas(std::make_unique<LineAtlas>(256, 512)),
+      observer(&nullObserver),
       workers(4) {
     glyphStore->setObserver(this);
     spriteStore->setObserver(this);
@@ -359,7 +363,7 @@ void Style::onLowMemory() {
     }
 }
 
-void Style::setObserver(Observer* observer_) {
+void Style::setObserver(StyleObserver* observer_) {
     observer = observer_;
 }
 
diff --git a/src/mbgl/style/style.hpp b/src/mbgl/style/style.hpp
index eca1236697..6a1af4cc9c 100644
--- a/src/mbgl/style/style.hpp
+++ b/src/mbgl/style/style.hpp
@@ -6,9 +6,9 @@
 #include <mbgl/style/types.hpp>
 #include <mbgl/style/property_transition.hpp>
 
-#include <mbgl/source/source.hpp>
-#include <mbgl/text/glyph_store.hpp>
-#include <mbgl/sprite/sprite_store.hpp>
+#include <mbgl/source/source_observer.hpp>
+#include <mbgl/text/glyph_store_observer.hpp>
+#include <mbgl/sprite/sprite_store_observer.hpp>
 #include <mbgl/map/mode.hpp>
 
 #include <mbgl/util/noncopyable.hpp>
@@ -20,6 +20,7 @@
 #include <cstdint>
 #include <string>
 #include <vector>
+#include <set>
 
 namespace mbgl {
 
@@ -31,6 +32,7 @@ class SpriteAtlas;
 class LineAtlas;
 class StyleUpdateParameters;
 class StyleQueryParameters;
+class StyleObserver;
 
 struct RenderData {
     Color backgroundColor = {{ 0, 0, 0, 0 }};
@@ -38,31 +40,17 @@ struct RenderData {
     std::vector<RenderItem> order;
 };
 
-class Style : public GlyphStore::Observer,
-              public SpriteStore::Observer,
-              public Source::Observer,
+class Style : public GlyphStoreObserver,
+              public SpriteStoreObserver,
+              public SourceObserver,
               public util::noncopyable {
 public:
     Style(FileSource&, float pixelRatio);
     ~Style();
 
-    class Observer : public GlyphStore::Observer,
-                     public SpriteStore::Observer,
-                     public Source::Observer {
-    public:
-        /**
-         * In addition to the individual glyph, sprite, and source events, the
-         * following "rollup" events are provided for convenience. They are
-         * strictly additive; e.g. when a source is loaded, both `onSourceLoaded`
-         * and `onResourceLoaded` will be called.
-         */
-         virtual void onResourceLoaded() {};
-         virtual void onResourceError(std::exception_ptr) {};
-    };
-
     void setJSON(const std::string& data, const std::string& base);
 
-    void setObserver(Observer*);
+    void setObserver(StyleObserver*);
 
     bool isLoaded() const;
 
@@ -120,23 +108,22 @@ private:
 
     std::vector<std::unique_ptr<StyleLayer>>::const_iterator findLayer(const std::string& layerID) const;
 
-    // GlyphStore::Observer implementation.
+    // GlyphStoreObserver implementation.
     void onGlyphsLoaded(const FontStack&, const GlyphRange&) override;
     void onGlyphsError(const FontStack&, const GlyphRange&, std::exception_ptr) override;
 
-    // SpriteStore::Observer implementation.
+    // SpriteStoreObserver implementation.
     void onSpriteLoaded() override;
     void onSpriteError(std::exception_ptr) override;
 
-    // Source::Observer implementation.
+    // SourceObserver implementation.
     void onSourceLoaded(Source&) override;
     void onSourceError(Source&, std::exception_ptr) override;
     void onTileLoaded(Source&, const OverscaledTileID&, bool isNewTile) override;
     void onTileError(Source&, const OverscaledTileID&, std::exception_ptr) override;
     void onPlacementRedone() override;
 
-    Observer nullObserver;
-    Observer* observer = &nullObserver;
+    StyleObserver* observer = nullptr;
 
     std::exception_ptr lastError;
 
diff --git a/src/mbgl/style/style_observer.hpp b/src/mbgl/style/style_observer.hpp
new file mode 100644
index 0000000000..c725334c10
--- /dev/null
+++ b/src/mbgl/style/style_observer.hpp
@@ -0,0 +1,26 @@
+#ifndef MBGL_STYLE_STYLE_OBSERVER
+#define MBGL_STYLE_STYLE_OBSERVER
+
+#include <mbgl/text/glyph_store_observer.hpp>
+#include <mbgl/sprite/sprite_store_observer.hpp>
+#include <mbgl/source/source_observer.hpp>
+
+namespace mbgl {
+
+class StyleObserver : public GlyphStoreObserver, public SpriteStoreObserver, public SourceObserver {
+public:
+    virtual ~StyleObserver() = default;
+
+    /**
+     * In addition to the individual glyph, sprite, and source events, the
+     * following "rollup" events are provided for convenience. They are
+     * strictly additive; e.g. when a source is loaded, both `onSourceLoaded`
+     * and `onResourceLoaded` will be called.
+     */
+    virtual void onResourceLoaded() {}
+    virtual void onResourceError(std::exception_ptr) {}
+};
+
+} // namespace mbgl
+
+#endif
diff --git a/src/mbgl/text/glyph_pbf.cpp b/src/mbgl/text/glyph_pbf.cpp
index eab9725075..9046464c5c 100644
--- a/src/mbgl/text/glyph_pbf.cpp
+++ b/src/mbgl/text/glyph_pbf.cpp
@@ -3,7 +3,7 @@
 #include <mbgl/storage/file_source.hpp>
 #include <mbgl/storage/resource.hpp>
 #include <mbgl/storage/response.hpp>
-#include <mbgl/text/glyph_store.hpp>
+#include <mbgl/text/glyph_store_observer.hpp>
 #include <mbgl/text/glyph_set.hpp>
 #include <mbgl/util/exception.hpp>
 #include <mbgl/util/string.hpp>
@@ -65,7 +65,7 @@ namespace mbgl {
 GlyphPBF::GlyphPBF(GlyphStore* store,
                    const FontStack& fontStack,
                    const GlyphRange& glyphRange,
-                   GlyphStore::Observer* observer_,
+                   GlyphStoreObserver* observer_,
                    FileSource& fileSource)
     : parsed(false),
       observer(observer_) {
diff --git a/src/mbgl/text/glyph_pbf.hpp b/src/mbgl/text/glyph_pbf.hpp
index d281d2a04f..37e1b4dbd3 100644
--- a/src/mbgl/text/glyph_pbf.hpp
+++ b/src/mbgl/text/glyph_pbf.hpp
@@ -21,7 +21,7 @@ public:
     GlyphPBF(GlyphStore*,
              const FontStack&,
              const GlyphRange&,
-             GlyphStore::Observer*,
+             GlyphStoreObserver*,
              FileSource&);
     ~GlyphPBF();
 
@@ -32,7 +32,7 @@ public:
 private:
     std::atomic<bool> parsed;
     std::unique_ptr<AsyncRequest> req;
-    GlyphStore::Observer* observer = nullptr;
+    GlyphStoreObserver* observer = nullptr;
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/text/glyph_store.cpp b/src/mbgl/text/glyph_store.cpp
index 540908ed63..8ed2eeace5 100644
--- a/src/mbgl/text/glyph_store.cpp
+++ b/src/mbgl/text/glyph_store.cpp
@@ -1,12 +1,15 @@
 #include <mbgl/text/glyph_store.hpp>
+#include <mbgl/text/glyph_store_observer.hpp>
 #include <mbgl/text/glyph_pbf.hpp>
 
 #include <cassert>
 
 namespace mbgl {
 
+static GlyphStoreObserver nullObserver;
+
 GlyphStore::GlyphStore(FileSource& fileSource_)
-    : fileSource(fileSource_) {
+    : fileSource(fileSource_), observer(&nullObserver) {
 }
 
 GlyphStore::~GlyphStore() = default;
@@ -66,7 +69,7 @@ util::exclusive<GlyphSet> GlyphStore::getGlyphSet(const FontStack& fontStack) {
     return { it->second.get(), std::move(lock) };
 }
 
-void GlyphStore::setObserver(Observer* observer_) {
+void GlyphStore::setObserver(GlyphStoreObserver* observer_) {
     observer = observer_;
 }
 
diff --git a/src/mbgl/text/glyph_store.hpp b/src/mbgl/text/glyph_store.hpp
index f89ff80864..240da58b6e 100644
--- a/src/mbgl/text/glyph_store.hpp
+++ b/src/mbgl/text/glyph_store.hpp
@@ -18,20 +18,13 @@ namespace mbgl {
 
 class FileSource;
 class GlyphPBF;
+class GlyphStoreObserver;
 
 // The GlyphStore manages the loading and storage of Glyphs
 // and creation of GlyphSet objects. The GlyphStore lives
 // on the MapThread but can be queried from any thread.
 class GlyphStore : private util::noncopyable {
 public:
-    class Observer {
-    public:
-        virtual ~Observer() = default;
-
-        virtual void onGlyphsLoaded(const FontStack&, const GlyphRange&) {};
-        virtual void onGlyphsError(const FontStack&, const GlyphRange&, std::exception_ptr) {};
-    };
-
     GlyphStore(FileSource&);
     ~GlyphStore();
 
@@ -52,7 +45,7 @@ public:
         return glyphURL;
     }
 
-    void setObserver(Observer* observer);
+    void setObserver(GlyphStoreObserver* observer);
 
 private:
     void requestGlyphRange(const FontStack&, const GlyphRange&);
@@ -68,8 +61,7 @@ private:
 
     util::WorkQueue workQueue;
 
-    Observer nullObserver;
-    Observer* observer = &nullObserver;
+    GlyphStoreObserver* observer = nullptr;
 };
 
 } // namespace mbgl
diff --git a/src/mbgl/text/glyph_store_observer.hpp b/src/mbgl/text/glyph_store_observer.hpp
new file mode 100644
index 0000000000..2ed1b2d5d9
--- /dev/null
+++ b/src/mbgl/text/glyph_store_observer.hpp
@@ -0,0 +1,21 @@
+#ifndef MBGL_TEXT_GLYPH_STORE_OBSERVER
+#define MBGL_TEXT_GLYPH_STORE_OBSERVER
+
+#include <mbgl/style/types.hpp>
+#include <mbgl/text/glyph_range.hpp>
+
+#include <exception>
+
+namespace mbgl {
+
+class GlyphStoreObserver {
+public:
+    virtual ~GlyphStoreObserver() = default;
+
+    virtual void onGlyphsLoaded(const FontStack&, const GlyphRange&) {}
+    virtual void onGlyphsError(const FontStack&, const GlyphRange&, std::exception_ptr) {}
+};
+
+} // namespace mbgl
+
+#endif