4 files changed, 74 insertions, 7 deletions
diff --git a/platform/default/mbgl/gl/headless_backend.cpp b/platform/default/mbgl/gl/headless_backend.cpp
index df3a517823..82cf7b38fd 100644
--- a/platform/default/mbgl/gl/headless_backend.cpp
+++ b/platform/default/mbgl/gl/headless_backend.cpp
@@ -16,7 +16,7 @@ HeadlessBackend::HeadlessBackend(std::shared_ptr<HeadlessDisplay> display_)
 }
 
 HeadlessBackend::~HeadlessBackend() {
-    BackendScope scope(*this);
+    BackendScope guard { *this, getScopeType() };
     context.reset();
 }
 
@@ -44,8 +44,4 @@ void HeadlessBackend::updateAssumedState() {
     // no-op
 }
 
-void HeadlessBackend::invalidate() {
-    assert(false);
-}
-
 } // namespace mbgl
diff --git a/platform/default/mbgl/gl/headless_backend.hpp b/platform/default/mbgl/gl/headless_backend.hpp
index 26033acf82..7b9f7f5ad3 100644
--- a/platform/default/mbgl/gl/headless_backend.hpp
+++ b/platform/default/mbgl/gl/headless_backend.hpp
@@ -17,8 +17,6 @@ public:
 
     void updateAssumedState() override;
 
-    void invalidate() override;
-
     struct Impl {
         virtual ~Impl() = default;
         virtual void activateContext() = 0;
diff --git a/platform/default/mbgl/renderer/async_renderer_frontend.cpp b/platform/default/mbgl/renderer/async_renderer_frontend.cpp
new file mode 100644
index 0000000000..37b4e60cf6
--- /dev/null
+++ b/platform/default/mbgl/renderer/async_renderer_frontend.cpp
@@ -0,0 +1,38 @@
+#include "async_renderer_frontend.hpp"
+#include <mbgl/renderer/renderer.hpp>
+
+namespace mbgl {
+
+AsyncRendererFrontend::AsyncRendererFrontend(std::unique_ptr<Renderer> renderer_, View& view_)
+    : renderer(std::move(renderer_))
+    , view(view_)
+    , asyncInvalidate([this] {
+        if (renderer && updateParameters) {
+            renderer->render(view, *updateParameters);
+        }
+    }) {
+}
+
+AsyncRendererFrontend::~AsyncRendererFrontend() = default;
+
+void AsyncRendererFrontend::reset() {
+    assert(renderer);
+    renderer.reset();
+}
+
+void AsyncRendererFrontend::update(std::shared_ptr<UpdateParameters> updateParameters_) {
+    updateParameters = updateParameters_;
+    asyncInvalidate.send();
+}
+
+void AsyncRendererFrontend::setObserver(RendererObserver& observer_) {
+    assert(renderer);
+    renderer->setObserver(&observer_);
+}
+    
+Renderer* AsyncRendererFrontend::getRenderer() {
+    assert(renderer);
+    return renderer.get();
+}
+
+} // namespace mbgl
diff --git a/platform/default/mbgl/renderer/async_renderer_frontend.hpp b/platform/default/mbgl/renderer/async_renderer_frontend.hpp
new file mode 100644
index 0000000000..00cf3a480c
--- /dev/null
+++ b/platform/default/mbgl/renderer/async_renderer_frontend.hpp
@@ -0,0 +1,35 @@
+#pragma once
+
+#include <mbgl/map/view.hpp>
+#include <mbgl/renderer/renderer_frontend.hpp>
+#include <mbgl/util/async_task.hpp>
+
+#include <memory>
+#include <vector>
+
+namespace mbgl {
+    
+class Renderer;
+
+// Default implementation for RendererFrontend
+class AsyncRendererFrontend : public mbgl::RendererFrontend {
+public:
+    AsyncRendererFrontend(std::unique_ptr<Renderer>, View&);
+    ~AsyncRendererFrontend() override;
+
+    void reset() override;
+
+    void update(std::shared_ptr<UpdateParameters> updateParameters_) override;
+    
+    void setObserver(RendererObserver& observer_) override;
+    
+    Renderer* getRenderer();
+    
+private:
+    std::unique_ptr<Renderer> renderer;
+    View& view;
+    std::shared_ptr<UpdateParameters> updateParameters;
+    util::AsyncTask asyncInvalidate;
+};
+    
+} // namespace mbgl