add onStyleImageMissing

10 files changed, 74 insertions, 2 deletions

diff --git a/include/mbgl/map/map_observer.hpp b/include/mbgl/map/map_observer.hpp
index 8ad9e93d0b..39fe516ff3 100644
--- a/include/mbgl/map/map_observer.hpp
+++ b/include/mbgl/map/map_observer.hpp
@@ -46,6 +46,7 @@ public:
     virtual void onDidFinishLoadingStyle() {}
     virtual void onSourceChanged(style::Source&) {}
     virtual void onDidBecomeIdle() {}
+    virtual void onStyleImageMissing(const std::string&) {}
 };
 
 } // namespace mbgl
diff --git a/include/mbgl/renderer/renderer_observer.hpp b/include/mbgl/renderer/renderer_observer.hpp
index 0a76d01ca7..71620355e8 100644
--- a/include/mbgl/renderer/renderer_observer.hpp
+++ b/include/mbgl/renderer/renderer_observer.hpp
@@ -31,6 +31,9 @@ public:
 
     // Final frame
     virtual void onDidFinishRenderingMap() {}
+
+    // Style is missing an image
+    virtual void onStyleImageMissing(const std::string&) {}
 };
 
 } // namespace mbgl
diff --git a/src/core-files.json b/src/core-files.json
index 139b93e368..b257666e3e 100644
--- a/src/core-files.json
+++ b/src/core-files.json
@@ -615,6 +615,7 @@
         "mbgl/renderer/group_by_layout.hpp": "src/mbgl/renderer/group_by_layout.hpp",
         "mbgl/renderer/image_atlas.hpp": "src/mbgl/renderer/image_atlas.hpp",
         "mbgl/renderer/image_manager.hpp": "src/mbgl/renderer/image_manager.hpp",
+        "mbgl/renderer/image_manager_observer.hpp": "src/mbgl/renderer/image_manager_observer.hpp",
         "mbgl/renderer/layers/render_background_layer.hpp": "src/mbgl/renderer/layers/render_background_layer.hpp",
         "mbgl/renderer/layers/render_circle_layer.hpp": "src/mbgl/renderer/layers/render_circle_layer.hpp",
         "mbgl/renderer/layers/render_custom_layer.hpp": "src/mbgl/renderer/layers/render_custom_layer.hpp",
diff --git a/src/mbgl/map/map_impl.cpp b/src/mbgl/map/map_impl.cpp
index 348e26700f..ecb9238362 100644
--- a/src/mbgl/map/map_impl.cpp
+++ b/src/mbgl/map/map_impl.cpp
@@ -172,4 +172,8 @@ void Map::Impl::jumpTo(const CameraOptions& camera) {
     onUpdate();
 }
 
+void Map::Impl::onStyleImageMissing(const std::string& id) {
+    observer.onStyleImageMissing(id);
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/map/map_impl.hpp b/src/mbgl/map/map_impl.hpp
index 13ffdc02ae..425e136b66 100644
--- a/src/mbgl/map/map_impl.hpp
+++ b/src/mbgl/map/map_impl.hpp
@@ -47,6 +47,7 @@ public:
     void onDidFinishRenderingFrame(RenderMode, bool) final;
     void onWillStartRenderingMap() final;
     void onDidFinishRenderingMap() final;
+    void onStyleImageMissing(const std::string&) final;
 
     // Map
     void jumpTo(const CameraOptions&);
diff --git a/src/mbgl/renderer/image_manager.cpp b/src/mbgl/renderer/image_manager.cpp
index 9c9f6c6e08..f756e201cb 100644
--- a/src/mbgl/renderer/image_manager.cpp
+++ b/src/mbgl/renderer/image_manager.cpp
@@ -1,9 +1,16 @@
 #include <mbgl/renderer/image_manager.hpp>
 #include <mbgl/util/logging.hpp>
 #include <mbgl/gfx/context.hpp>
+#include <mbgl/renderer/image_manager_observer.hpp>
 
 namespace mbgl {
 
+static ImageManagerObserver nullObserver;
+
+void ImageManager::setObserver(ImageManagerObserver* observer_) {
+    observer = observer_ ? observer_ : &nullObserver;
+}
+
 void ImageManager::setLoaded(bool loaded_) {
     if (loaded == loaded_) {
         return;
@@ -13,7 +20,7 @@ void ImageManager::setLoaded(bool loaded_) {
 
     if (loaded) {
         for (const auto& entry : requestors) {
-            notify(*entry.first, entry.second);
+            checkMissingAndNotify(*entry.first, entry.second);
         }
         requestors.clear();
     }
@@ -73,7 +80,7 @@ void ImageManager::getImages(ImageRequestor& requestor, ImageRequestPair&& pair)
         }
     }
     if (isLoaded() || hasAllDependencies) {
-        notify(requestor, std::move(pair));
+        checkMissingAndNotify(requestor, std::move(pair));
     } else {
         requestors.emplace(&requestor, std::move(pair));
     }
@@ -81,6 +88,30 @@ void ImageManager::getImages(ImageRequestor& requestor, ImageRequestPair&& pair)
 
 void ImageManager::removeRequestor(ImageRequestor& requestor) {
     requestors.erase(&requestor);
+    missingImageRequestors.erase(&requestor);
+}
+
+void ImageManager::imagesAdded() {
+    for (const auto& entry : missingImageRequestors) {
+        notify(*entry.first, entry.second);
+    }
+    requestors.clear();
+}
+
+void ImageManager::checkMissingAndNotify(ImageRequestor& requestor, const ImageRequestPair& pair) {
+    bool missing = false;
+    for (const auto& dependency : pair.first) {
+        auto it = images.find(dependency.first);
+        if (it == images.end()) {
+            missing = true;
+            observer->onStyleImageMissing(dependency.first);
+        }
+    }
+    if (missing) {
+        missingImageRequestors.emplace(&requestor, std::move(pair));
+    } else {
+        notify(requestor, pair);
+    }
 }
 
 void ImageManager::notify(ImageRequestor& requestor, const ImageRequestPair& pair) const {
diff --git a/src/mbgl/renderer/image_manager.hpp b/src/mbgl/renderer/image_manager.hpp
index e56f30ac3f..9adb0fa113 100644
--- a/src/mbgl/renderer/image_manager.hpp
+++ b/src/mbgl/renderer/image_manager.hpp
@@ -6,6 +6,7 @@
 #include <mbgl/util/immutable.hpp>
 #include <mbgl/util/optional.hpp>
 #include <mbgl/gfx/texture.hpp>
+#include <mbgl/renderer/image_manager_observer.hpp>
 
 #include <mapbox/shelf-pack.hpp>
 
@@ -39,6 +40,8 @@ public:
     ImageManager();
     ~ImageManager();
 
+    void setObserver(ImageManagerObserver*);
+
     void setLoaded(bool);
     bool isLoaded() const;
 
@@ -52,15 +55,20 @@ public:
 
     void getImages(ImageRequestor&, ImageRequestPair&&);
     void removeRequestor(ImageRequestor&);
+    void imagesAdded();
 
 private:
+    void checkMissingAndNotify(ImageRequestor&, const ImageRequestPair&);
     void notify(ImageRequestor&, const ImageRequestPair&) const;
 
     bool loaded = false;
 
     std::unordered_map<ImageRequestor*, ImageRequestPair> requestors;
+    std::unordered_map<ImageRequestor*, ImageRequestPair> missingImageRequestors;
     ImageMap images;
 
+    ImageManagerObserver* observer = nullptr;
+
 // Pattern stuff
 public:
     optional<ImagePosition> getPattern(const std::string& name);
diff --git a/src/mbgl/renderer/image_manager_observer.hpp b/src/mbgl/renderer/image_manager_observer.hpp
new file mode 100644
index 0000000000..e483c5b8f6
--- /dev/null
+++ b/src/mbgl/renderer/image_manager_observer.hpp
@@ -0,0 +1,12 @@
+#pragma once
+
+namespace mbgl {
+
+class ImageManagerObserver {
+public:
+    virtual ~ImageManagerObserver() = default;
+
+    virtual void onStyleImageMissing(const std::string&) {}
+};
+
+} // namespace mbgl
diff --git a/src/mbgl/renderer/renderer_impl.cpp b/src/mbgl/renderer/renderer_impl.cpp
index 311008507b..adef3890bf 100644
--- a/src/mbgl/renderer/renderer_impl.cpp
+++ b/src/mbgl/renderer/renderer_impl.cpp
@@ -83,6 +83,7 @@ void Renderer::Impl::render(const UpdateParameters& updateParameters) {
 
     if (!imageManager) {
         imageManager = std::make_unique<ImageManager>();
+        imageManager->setObserver(this);
     }
 
     if (updateParameters.mode != MapMode::Continuous) {
@@ -158,6 +159,7 @@ void Renderer::Impl::render(const UpdateParameters& updateParameters) {
         imageManager->updateImage(entry.second.after);
     }
 
+    imageManager->imagesAdded();
     imageManager->setLoaded(updateParameters.spriteLoaded);
 
 
@@ -834,4 +836,8 @@ void Renderer::Impl::onTileChanged(RenderSource&, const OverscaledTileID&) {
     observer->onInvalidate();
 }
 
+void Renderer::Impl::onStyleImageMissing(const std::string& id) {
+    observer->onStyleImageMissing(id);
+}
+
 } // namespace mbgl
diff --git a/src/mbgl/renderer/renderer_impl.hpp b/src/mbgl/renderer/renderer_impl.hpp
index a036bfc7ff..8ec7d26988 100644
--- a/src/mbgl/renderer/renderer_impl.hpp
+++ b/src/mbgl/renderer/renderer_impl.hpp
@@ -11,6 +11,7 @@
 #include <mbgl/map/zoom_history.hpp>
 #include <mbgl/text/cross_tile_symbol_index.hpp>
 #include <mbgl/text/glyph_manager_observer.hpp>
+#include <mbgl/renderer/image_manager_observer.hpp>
 #include <mbgl/text/placement.hpp>
 
 #include <memory>
@@ -34,6 +35,7 @@ class LineAtlas;
 class CrossTileSymbolIndex;
 
 class Renderer::Impl : public GlyphManagerObserver,
+                       public ImageManagerObserver,
                        public RenderSourceObserver{
 public:
     Impl(RendererBackend&, float pixelRatio_, Scheduler&, GLContextMode,
@@ -86,6 +88,9 @@ private:
     void onTileChanged(RenderSource&, const OverscaledTileID&) override;
     void onTileError(RenderSource&, const OverscaledTileID&, std::exception_ptr) override;
 
+    // ImageManagerObserver implementation
+    void onStyleImageMissing(const std::string&) override;
+
     void updateFadingTiles();
 
     friend class Renderer;