Big changes

engine/include/sophia/application.hpp

@@ -8,6 +8,7 @@
 #include <sophia/console/console_command_registry.hpp>
 #include <sophia/frame_info.hpp>
 #include <sophia/resource_registry_ref.hpp>
+#include <sophia/scene_registry.hpp>
 #include <sophia/types.hpp>
 #include <sophia/ui/debug_ui.hpp>
 #include <sophia/ui/panel_registry.hpp>
@@ -47,6 +48,7 @@ class Application {
 
   ResourceRegistryRef resources();
   PanelRegistry& panels() { return this->panelRegistry; }
+  SceneRegistry& scenes() { return this->sceneRegistry; }
   UI& ui() { return this->_ui; }
 
   DebugUI& debugUI() { return this->_debugUI; }
@@ -60,6 +62,7 @@ class Application {
   void drawMesh(MeshHandle handle, const glm::mat4& transform);
 
   /**
+   * !TEMP !TODO remove this func eventually
    * Chooses where the scene is rendered. An invalid handle (the default) means
    * the swapchain; a target created with
    * ResourceRegistryRef::create<RenderTarget>() redirects it offscreen, and the
@@ -78,6 +81,7 @@ class Application {
   std::unique_ptr<Impl> impl;
 
   PanelRegistry panelRegistry;
+  SceneRegistry sceneRegistry;
   UI _ui;
 
   DebugUI _debugUI;

engine/include/sophia/resource_registry_ref.hpp

@@ -16,7 +16,6 @@ namespace sophia {
 
 class Mesh;
 class RenderTarget;
-class Scene;
 class ResourceRegistry;
 
 template <typename T>
@@ -32,11 +31,6 @@ struct ResourceTraits<RenderTarget> {
   using Handle = RenderTargetHandle;
 };
 
-template <>
-struct ResourceTraits<Scene> {
-  using Handle = SceneHandle;
-};
-
 class ResourceRegistryRef {
  public:
   template <typename T>
@@ -52,7 +46,6 @@ class ResourceRegistryRef {
   glm::vec2 getExtent(RenderTargetHandle handle) const;
 
   bool isAlive(RenderTargetHandle handle) const;
-  bool isAlive(SceneHandle handle) const;
 
   template <typename T>
   void release(typename ResourceTraits<T>::Handle handle);
@@ -70,8 +63,6 @@ class ResourceRegistryRef {
   RenderTargetHandle createResource(std::type_identity<RenderTarget>,
                                     u32 width = 1, u32 height = 1);
 
-  SceneHandle createResource(std::type_identity<Scene>);
-
   ResourceRegistry* registry;
 };
 
@@ -84,7 +75,4 @@ void ResourceRegistryRef::release<Mesh>(MeshHandle handle);
 template <>
 void ResourceRegistryRef::release<RenderTarget>(RenderTargetHandle handle);
 
-template <>
-void ResourceRegistryRef::release<Scene>(SceneHandle handle);
-
 }  // namespace sophia

engine/include/sophia/scene.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <entt/entt.hpp>
+
+namespace sophia {
+
+class Scene {
+ public:
+  Scene();
+  ~Scene();
+
+  // The camera a render request uses when it doesn't name one. Null until set.
+  entt::entity getActiveCamera() const { return activeCamera; }
+  void setActiveCamera(entt::entity camera) { activeCamera = camera; }
+
+ private:
+  entt::registry registry;
+  entt::entity activeCamera = entt::null;
+};
+
+}  // namespace sophia

engine/include/sophia/scene_registry.hpp

@@ -0,0 +1,31 @@
+#pragma once
+
+#include <sophia/handles.hpp>
+#include <sophia/scene.hpp>
+#include <sophia/util/pool.hpp>
+
+namespace sophia {
+
+class SceneRegistry {
+ public:
+  SceneRegistry(const SceneRegistry&) = delete;
+  SceneRegistry& operator=(const SceneRegistry&) = delete;
+
+  SceneRegistry() = default;
+  ~SceneRegistry() = default;
+
+  SceneHandle create() { return pool.create(); }
+
+  const Scene& get(SceneHandle handle) const { return pool.get(handle); }
+  Scene& get(SceneHandle handle) { return pool.get(handle); }
+
+  void release(SceneHandle handle) { pool.release(handle); }
+  bool isAlive(SceneHandle handle) const { return pool.isAlive(handle); }
+
+  u32 size() const { return pool.size(); }
+
+ private:
+  Pool<Scene, SceneHandle> pool{"Scene"};
+};
+
+}  // namespace sophia

engine/include/sophia/ui/panel_registry.hpp

@@ -6,6 +6,7 @@
 #include <sophia/ui/dock_layout.hpp>
 #include <sophia/ui/panel.hpp>
 #include <sophia/util/assert.hpp>
+#include <sophia/util/pool.hpp>
 #include <string_view>
 #include <typeinfo>
 #include <utility>
@@ -21,17 +22,17 @@ class PanelRegistry {
   PanelRegistry() = default;
   ~PanelRegistry() = default;
 
-  PanelHandle add(std::unique_ptr<Panel> panel);
+  PanelHandle add(std::unique_ptr<Panel> panel) {
+    return pool.add(std::move(panel));
+  }
 
   template <typename T, typename... Args>
   PanelHandle emplace(Args&&... args) {
     return add(std::make_unique<T>(std::forward<Args>(args)...));
   }
 
-  const Panel& get(PanelHandle handle) const;
-  Panel& get(PanelHandle handle) {
-    return const_cast<Panel&>(std::as_const(*this).get(handle));
-  }
+  const Panel& get(PanelHandle handle) const { return pool.get(handle); }
+  Panel& get(PanelHandle handle) { return pool.get(handle); }
 
   template <typename T>
   const T& get(PanelHandle handle) const {
@@ -46,19 +47,17 @@ class PanelRegistry {
     return const_cast<T&>(std::as_const(*this).template get<T>(handle));
   }
 
-  void remove(PanelHandle handle);
-  bool isValid(PanelHandle handle) const;
+  void remove(PanelHandle handle) { pool.release(handle); }
+  bool isValid(PanelHandle handle) const { return pool.isAlive(handle); }
 
   template <typename T>
   const T* find() const {
-    for (const Slot& slot : slots) {
-      if (slot.panel) {
-        if (const T* panel = dynamic_cast<const T*>(slot.panel.get())) {
-          return panel;
-        }
-      }
-    }
-    return nullptr;
+    const T* result = nullptr;
+    pool.findIf([&result](const Panel& panel) {
+      result = dynamic_cast<const T*>(&panel);
+      return result != nullptr;
+    });
+    return result;
   }
 
   template <typename T>
@@ -67,29 +66,22 @@ class PanelRegistry {
   }
 
   const Panel* find(std::string_view name) const {
-    for (const Slot& slot : slots) {
-      if (slot.panel && slot.panel->getName() == name) {
-        return slot.panel.get();
-      }
-    }
-    return nullptr;
+    return pool.findIf(
+        [name](const Panel& panel) { return panel.getName() == name; });
   }
 
   Panel* find(std::string_view name) {
     return const_cast<Panel*>(std::as_const(*this).find(name));
   }
 
-  u32 size() const;
+  u32 size() const { return pool.size(); }
   u32 visibleCount() const;
 
   std::vector<std::string_view> names() const {
     std::vector<std::string_view> result;
-    result.reserve(slots.size());
-    for (const Slot& slot : slots) {
-      if (slot.panel) {
-        result.push_back(slot.panel->getName());
-      }
-    }
+    result.reserve(pool.size());
+    pool.forEach(
+        [&result](const Panel& panel) { result.push_back(panel.getName()); });
     return result;
   }
 
@@ -101,13 +93,7 @@ class PanelRegistry {
   const DockLayout& getDefaultLayout() const { return defaultLayout; }
 
  private:
-  struct Slot {
-    std::unique_ptr<Panel> panel;
-    u32 generation = 0;
-  };
-
-  std::vector<Slot> slots;
-  std::vector<u32> freeList;
+  Pool<Panel, PanelHandle> pool{"Panel"};
   DockLayout defaultLayout;
 };
 

engine/include/sophia/util/pool.hpp

@@ -0,0 +1,119 @@
+#pragma once
+
+#include <memory>
+#include <sophia/types.hpp>
+#include <sophia/util/assert.hpp>
+#include <utility>
+#include <vector>
+
+namespace sophia {
+
+template <typename T, typename HandleType>
+class Pool {
+ public:
+  explicit Pool(const char* name) : name{name} {}
+
+  Pool(const Pool&) = delete;
+  Pool& operator=(const Pool&) = delete;
+
+  template <typename... Args>
+  HandleType create(Args&&... args) {
+    return add(std::make_unique<T>(std::forward<Args>(args)...));
+  }
+
+  HandleType add(std::unique_ptr<T> item) {
+    if (!freeList.empty()) {
+      u32 index = freeList.back();
+      freeList.pop_back();
+      slots[index].item = std::move(item);
+      return HandleType{index, slots[index].generation};
+    }
+
+    slots.push_back(Slot{std::move(item), 0});
+    return HandleType{static_cast<u32>(slots.size() - 1), 0};
+  }
+
+  T& get(HandleType handle) {
+    return const_cast<T&>(std::as_const(*this).get(handle));
+  }
+
+  const T& get(HandleType handle) const { return *validate(handle).item; }
+
+  void release(HandleType handle) {
+    validate(handle);
+
+    Slot& slot = slots[handle.index];
+    slot.item.reset();
+    slot.generation = (slot.generation + 1) & GENERATION_MASK;
+    freeList.push_back(handle.index);
+  }
+
+  bool isAlive(HandleType handle) const {
+    return handle.isValid() && handle.index < slots.size() &&
+           slots[handle.index].generation == handle.generation &&
+           slots[handle.index].item != nullptr;
+  }
+
+  u32 size() const { return static_cast<u32>(slots.size() - freeList.size()); }
+
+  template <typename Fn>
+  void forEach(Fn&& fn) {
+    for (Slot& slot : slots) {
+      if (slot.item) {
+        fn(*slot.item);
+      }
+    }
+  }
+
+  template <typename Fn>
+  void forEach(Fn&& fn) const {
+    for (const Slot& slot : slots) {
+      if (slot.item) {
+        fn(*slot.item);
+      }
+    }
+  }
+
+  template <typename Predicate>
+  T* findIf(Predicate&& predicate) {
+    return const_cast<T*>(
+        std::as_const(*this).findIf(std::forward<Predicate>(predicate)));
+  }
+
+  template <typename Predicate>
+  const T* findIf(Predicate&& predicate) const {
+    for (const Slot& slot : slots) {
+      if (slot.item && predicate(*slot.item)) {
+        return slot.item.get();
+      }
+    }
+    return nullptr;
+  }
+
+ private:
+  static constexpr u32 GENERATION_MASK = (1u << 12) - 1;
+
+  struct Slot {
+    std::unique_ptr<T> item;
+    u32 generation = 0;
+  };
+
+  const Slot& validate(HandleType handle) const {
+    SOPHIA_ASSERT(handle.isValid(), "invalid handle:", name);
+    SOPHIA_ASSERT(handle.index < slots.size(), name,
+                  "handle index out of range:", handle.index);
+
+    const Slot& slot = slots[handle.index];
+    SOPHIA_ASSERT(slot.generation == handle.generation, "stale", name,
+                  "handle (generation mismatch):", handle.index);
+    SOPHIA_ASSERT(slot.item != nullptr, name,
+                  "handle refers to a released item:", handle.index);
+    return slot;
+  }
+
+  const char* name;
+  std::vector<Slot> slots;
+  std::vector<u32> freeList;
+};
+
+}  // namespace sophia