改造一些

render_2D/renderable/Renderable.cpp

@@ -48,8 +48,10 @@ void Renderable::render(const ::Scene_Render_Context& context) {
     if (!cache)
         return;
     detail::Painter painter(*cache, viewport_size());
-    if (painter)
-        paint(painter);
+    if (painter) {
+        const auto state = render_state_view();
+        paint(painter, state);
+    }
 }
 
 void Renderable::changed() noexcept {

render_2D/renderable/Renderable.h

@@ -14,6 +14,7 @@ namespace renderive {
 class Plot_Core;
 namespace detail {
 class Painter;
+class Renderable_State_Observer;
 }
 
 class Event_Handler {
@@ -39,15 +40,36 @@ public:
     void render(const ::Scene_Render_Context& context) final;
 
 protected:
-    virtual void paint(detail::Painter& painter) = 0;
+    virtual void paint(detail::Painter& painter, const Render_State_View& state) = 0;
     void changed() noexcept;
     [[nodiscard]] Size viewport_size() const noexcept;
 
 private:
+    friend class detail::Renderable_State_Observer;
     Plot_Core& plot_;
     mutable std::mutex metadata_mutex_;
     std::string object_name_;
     std::atomic<bool> visible_{true};
 };
 
+namespace detail {
+
+class Renderable_State_Observer {
+public:
+    static constexpr bool enabled = true;
+
+    explicit Renderable_State_Observer(Renderable* renderable) noexcept : renderable_(renderable) {}
+
+    template <class Observation>
+    void observe(const Observation& observation) noexcept {
+        if (observation.event == decltype(observation.event)::cache_updated)
+            renderable_->changed();
+    }
+
+private:
+    Renderable* renderable_;
+};
+
+} // namespace detail
+
 } // namespace renderive