Widgets::Scene: inherit Scene, fix docs and improve naming

This commit improves readability and maintainability of
the project by unifying the interface via inheritance.

Also, local functions were made static.

include/common/algine/core/widgets/Scene.h

@@ -5,6 +5,7 @@
 #include <algine/core/painter/Painter.h>
 #include <algine/core/math/Size.h>
 #include <algine/core/unified/UnifiedEventHandler.h>
+#include <algine/core/scene/Scene.h>
 
 namespace algine {
 class Widget;
@@ -20,37 +21,28 @@ class Layer;
  * <ol>
  *   <li>Inherit your custom scene from <code>algine::Widgets::Scene</code></li>
  *   <li>Load layers (make them as children of the scene)</li>
- *   <li>Add listeners to <code>XEventHandler</code>: call <code>listen(handler)</code>
+ *   <li>Add listeners to <code>UnifiedEventHandler</code>: call <code>listen(handler)</code>
  *   <li>Call <code>setSize(width, height)</code></li>
  *   <li>Show your start layer: <code>scene->showLayer(scene->myStartLayer)</code></li>
- *   <li>In the render loop draw UI: <code>scene.draw()</code></li>
+ *   <li>In the render loop draw UI: <code>scene.render()</code></li>
  * </ol>
  */
-class AL_EXPORT Scene: public Object {
+class AL_EXPORT Scene: public algine::Scene {
 public:
     explicit Scene(Object *parent = defaultParent());
     Scene(int width, int height, Object *parent = defaultParent());
     ~Scene() override = default;
 
-    /**
-     * Draws layers from level <code>begin</code> to <code>end</code>
-     * <br>If <code>end</code> is less than zero, it will be set to
-     * layers count
-     * @param begin
-     * @param end
-     */
-    void draw(int begin = 0, int end = -1);
-
     void showLayer(Layer *layer, int level = -1);
-    void showLayerInsteadOf(Layer *replacement, Layer *src);
+    void replaceLayer(Layer *src, Layer *replacement);
     void hideLayer(Layer *layer);
-    void hideLevel(int level);
+    void hideLevelAt(int level);
 
     Layer* layerAt(int level) const;
     Layer* getTopLayer() const;
 
     int getLevel(const Layer *layer) const;
-    int getLayersCount() const;
+    int getLayerCount() const;
 
     /**
      * @note ownership of the object will not be transferred to the scene
@@ -82,7 +74,19 @@ class AL_EXPORT Scene: public Object {
 
     Painter* getPainter() const;
 
+protected:
+    void onRender() override;
+
 private:
+    /**
+     * Draws layers from level <code>begin</code> to <code>end</code>
+     * <br>If <code>end</code> is less than zero, it will be set to
+     * layers count
+     * @param begin
+     * @param end
+     */
+    void draw(int begin = 0, int end = -1);
+
     bool handlePointerEvent(const Event &event);
     bool handleKeyboardEvent(const Event &event);
 

src/common/core/widgets/Scene.cpp

@@ -8,7 +8,7 @@ using namespace tulz;
 
 namespace algine::Widgets {
 Scene::Scene(Object *parent)
-    : Object(parent),
+    : algine::Scene(parent),
       m_painter(new Painter(this))
 {
     m_options.painter = m_painter;
@@ -28,9 +28,9 @@ Scene::Scene(int width, int height, Object *parent)
  * @param insert must be set to false for non-opaque layers
  * @complexity <code>O(NlogN)</code>
  * @return <code>true</code> if <code>rect</code> is visible
- * and was added to the heap, otherwise <code>false</code>
+ * (and was added to the heap, if specified), otherwise <code>false</code>
  */
-bool placeRect(std::vector<RectI> &heap, const RectI &rect, bool insert) {
+static bool placeRect(std::vector<RectI> &heap, const RectI &rect, bool insert) {
     if (heap.empty()) {
         heap.emplace_back(rect);
         return true;
@@ -131,7 +131,7 @@ void Scene::showLayer(Layer *layer, int level) {
     layer->onShow();
 }
 
-void Scene::showLayerInsteadOf(Layer *replacement, Layer *src) {
+void Scene::replaceLayer(Layer *src, Layer *replacement) {
     assert(src->getParent() == this);
     assert(replacement->getParent() == this);
 
@@ -154,10 +154,10 @@ void Scene::hideLayer(Layer *layer) {
     if (level == -1)
         throw std::runtime_error("Layer was not found at this Scene");
 
-    hideLevel(level);
+    hideLevelAt(level);
 }
 
-void Scene::hideLevel(int level) {
+void Scene::hideLevelAt(int level) {
     m_layers[level]->onHide();
     m_layers.erase(m_layers.begin() + level);
 }
@@ -175,7 +175,7 @@ int Scene::getLevel(const Layer *layer) const {
     return it == m_layers.end() ? -1 : static_cast<int>(std::distance(m_layers.begin(), it));
 }
 
-int Scene::getLayersCount() const {
+int Scene::getLayerCount() const {
     return static_cast<int>(m_layers.size());
 }
 
@@ -254,13 +254,17 @@ Painter* Scene::getPainter() const {
     return m_painter;
 }
 
+void Scene::onRender() {
+    draw();
+}
+
 bool Scene::handlePointerEvent(const Event &event) {
     auto &info = event.getPointerInfo();
     PointI globalPoint {(int) info.getX(), (int) info.getY()};
 
     // returns a widget on the scene at globalPoint
     auto findWidget = [this, &globalPoint]() -> Widget* {
-        for (int i = getLayersCount() - 1; i >= 0; --i) {
+        for (int i = getLayerCount() - 1; i >= 0; --i) {
             auto container = layerAt(i)->getContainer();
             PointI container_lp = container->mapFromGlobal(globalPoint);