1 files changed, 56 insertions, 0 deletions
diff --git a/include/mbgl/layermanager/layer_manager.hpp b/include/mbgl/layermanager/layer_manager.hpp
new file mode 100644
index 0000000000..038a6dcb04
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+++ b/include/mbgl/layermanager/layer_manager.hpp
@@ -0,0 +1,56 @@
+#pragma once
+
+#include <mbgl/style/layer.hpp>
+
+namespace mbgl {
+
+class LayerFactory;
+class RenderLayer;
+
+/**
+ * @brief A singleton class responsible for creating layer instances.
+ * 
+ * The LayerManager has implementation per platform. The LayerManager implementation
+ * defines what layer types are available and it can also disable annotations.
+ * 
+ * Linker excludes the unreachable code for the disabled annotations and layers
+ * from the binaries, significantly reducing their size.
+ */
+class LayerManager {
+public:
+    /**
+     * @brief A singleton getter.
+     * 
+     * @return LayerManager* 
+     */
+    static LayerManager* get() noexcept;
+
+    /// Returns a new Layer instance on success call; returns `nulltptr` otherwise.
+    std::unique_ptr<style::Layer> createLayer(const std::string& type, const std::string& id,
+                                              const style::conversion::Convertible& value, style::conversion::Error& error) noexcept;
+    /// Returns a new RenderLayer instance on success call; returns `nulltptr` otherwise.
+    std::unique_ptr<RenderLayer> createRenderLayer(Immutable<style::Layer::Impl>) noexcept;
+
+    /**
+     * @brief a build-time flag to enable/disable annotations in mapbox-gl-native core.
+     * 
+     * At the moment, the annotations implementation in core is creating concrete
+     * layer instances apart from LayerManager/LayerFactory code path.
+     * 
+     * So, annotations must be disabled if the LayerManager implementation does
+     * not provide line, fill or symbol layers (those, used by the annotations 
+     * implementation).
+     * 
+     * Note: in future, annotations implemantation will be moved from the core to platform 
+     * SDK (see https://github.com/mapbox/mapbox-plugins-android/tree/master/plugin-annotation)
+     * and this flag won't be needed any more.
+     */
+    static const bool annotationsEnabled;
+
+protected:
+    virtual ~LayerManager() = default;
+    virtual LayerFactory* getFactory(const std::string& type) noexcept = 0;
+    virtual LayerFactory* getFactory(const style::LayerTypeInfo*) noexcept = 0;
+};
+
+} // namespace mbgl