Directory structure cleanup and organization overhaul

tests/unified_click_example.cpp

@@ -0,0 +1,101 @@
+// Example of how UIFrame would implement unified click handling
+//
+// Click Priority Example:
+// - Dialog Frame (has click handler to drag window)
+//   - Title Caption (no click handler)
+//   - Button Frame (has click handler)
+//     - Button Caption "OK" (no click handler)
+//   - Close X Sprite (has click handler)
+//
+// Clicking on:
+// - "OK" text -> Button Frame gets the click (deepest parent with handler)
+// - Close X -> Close sprite gets the click 
+// - Title bar -> Dialog Frame gets the click (no child has handler there)
+// - Outside dialog -> nullptr (bounds check fails)
+
+class UIFrame : public UIDrawable, protected RectangularContainer {
+private:
+    // Implementation of container interface
+    sf::Vector2f toChildCoordinates(sf::Vector2f localPoint, int childIndex) const override {
+        // Children use same coordinate system as frame's local coordinates
+        return localPoint;
+    }
+    
+    UIDrawable* getClickHandler() override {
+        return click_callable ? this : nullptr;
+    }
+    
+    std::vector<UIDrawable*> getClickableChildren() override {
+        std::vector<UIDrawable*> result;
+        for (auto& child : *children) {
+            result.push_back(child.get());
+        }
+        return result;
+    }
+    
+public:
+    UIDrawable* click_at(sf::Vector2f point) override {
+        // Update bounds from box
+        bounds = sf::FloatRect(box.getPosition().x, box.getPosition().y, 
+                              box.getSize().x, box.getSize().y);
+        
+        // Use unified handler
+        return handleClick(point);
+    }
+};
+
+// Example for UIGrid with entity coordinate transformation
+class UIGrid : public UIDrawable, protected RectangularContainer {
+private:
+    sf::Vector2f toChildCoordinates(sf::Vector2f localPoint, int childIndex) const override {
+        // For entities, we need to transform from pixel coordinates to grid coordinates
+        // This is where the grid's special coordinate system is handled
+        
+        // Assuming entity positions are in grid cells, not pixels
+        // We pass pixel coordinates relative to the grid's rendering area
+        return localPoint; // Entities will handle their own sprite positioning
+    }
+    
+    std::vector<UIDrawable*> getClickableChildren() override {
+        std::vector<UIDrawable*> result;
+        
+        // Only check entities that are visible on screen
+        float left_edge = center_x - (box.getSize().x / 2.0f) / (grid_size * zoom);
+        float top_edge = center_y - (box.getSize().y / 2.0f) / (grid_size * zoom);
+        float right_edge = left_edge + (box.getSize().x / (grid_size * zoom));
+        float bottom_edge = top_edge + (box.getSize().y / (grid_size * zoom));
+        
+        for (auto& entity : entities) {
+            // Check if entity is within visible bounds
+            if (entity->position.x >= left_edge - 1 && entity->position.x < right_edge + 1 &&
+                entity->position.y >= top_edge - 1 && entity->position.y < bottom_edge + 1) {
+                result.push_back(&entity->sprite);
+            }
+        }
+        return result;
+    }
+};
+
+// For Scene, which has no coordinate transformation
+class PyScene : protected UIContainerBase {
+private:
+    sf::Vector2f toLocalCoordinates(sf::Vector2f point) const override {
+        // Scene uses window coordinates directly
+        return point;
+    }
+    
+    sf::Vector2f toChildCoordinates(sf::Vector2f localPoint, int childIndex) const override {
+        // Top-level drawables use window coordinates
+        return localPoint;
+    }
+    
+    bool containsPoint(sf::Vector2f localPoint) const override {
+        // Scene contains all points (full window)
+        return true;
+    }
+    
+    UIDrawable* getClickHandler() override {
+        // Scene itself doesn't handle clicks
+        return nullptr;
+    }
+};