scene_view concept

engine/include/sophia/application.hpp

@@ -10,6 +10,7 @@
 #include <sophia/math.hpp>
 #include <sophia/resource_registry_ref.hpp>
 #include <sophia/scene_registry.hpp>
+#include <sophia/scene_view_registry.hpp>
 #include <sophia/types.hpp>
 #include <sophia/ui/debug_ui.hpp>
 #include <sophia/ui/panel_registry.hpp>
@@ -46,6 +47,7 @@ class Application {
   ResourceRegistryRef resources();
   PanelRegistry& panels() { return this->panelRegistry; }
   SceneRegistry& scenes() { return this->sceneRegistry; }
+  SceneViewRegistry& views() { return this->sceneViewRegistry; }
   UI& ui() { return this->_ui; }
 
   DebugUI& debugUI() { return this->_debugUI; }
@@ -58,16 +60,6 @@ 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
-   * swapchain then only receives the UI. FrameInfo::currentFramebufferExtent
-   * and the camera projection follow the target's size.
-   */
-  void setSceneTarget(RenderTargetHandle handle);
-
  private:
   friend class Canvas;
 
@@ -79,6 +71,7 @@ class Application {
 
   PanelRegistry panelRegistry;
   SceneRegistry sceneRegistry;
+  SceneViewRegistry sceneViewRegistry;
   UI _ui;
 
   DebugUI _debugUI;

engine/include/sophia/handles.hpp

@@ -37,10 +37,12 @@ class Mesh;
 class Panel;
 class RenderTarget;
 class Scene;
+struct SceneView;
 
 using MeshHandle = Handle<Mesh>;
 using PanelHandle = Handle<Panel>;
 using RenderTargetHandle = Handle<RenderTarget>;
 using SceneHandle = Handle<Scene>;
+using SceneViewHandle = Handle<SceneView>;
 
 }  // namespace sophia

engine/include/sophia/scene_view.hpp

@@ -0,0 +1,34 @@
+#pragma once
+
+#include <sophia/entity.hpp>
+#include <sophia/handles.hpp>
+#include <sophia/math.hpp>
+#include <sophia/scene.hpp>
+
+namespace sophia {
+
+enum class ClearFlags : u8 {
+  None = 0,
+  Color = 1 << 0,
+  Depth = 1 << 1,
+  Stencil = 1 << 2,
+  All = Color | Depth | Stencil
+};
+
+struct SceneView {
+  SceneHandle scene = INVALID_HANDLE;
+  RenderTargetHandle target = INVALID_HANDLE;
+  Entity camera;
+
+  vec4 viewport{0.0f, 0.0f, 1.0f, 1.0f};
+
+  vec4 clearColor{0.f, 0.f, 0.f, 1.f};
+  ClearFlags clearFlags = ClearFlags::All;
+
+  u32 priority = 0;  // Lower priority renders first
+  u32 layerMask = 0xFFFFFFFF;
+
+  bool enabled = true;  // Disabled views are kept but not rendered
+};
+
+}  // namespace sophia

engine/include/sophia/scene_view_registry.hpp

@@ -0,0 +1,86 @@
+#pragma once
+
+#include <algorithm>
+#include <sophia/handles.hpp>
+#include <sophia/scene_view.hpp>
+#include <sophia/util/pool.hpp>
+#include <utility>
+#include <vector>
+
+namespace sophia {
+
+/**
+ * Every live SceneView. The application renders all enabled views each frame,
+ * in ascending priority order, before the UI.
+ */
+class SceneViewRegistry {
+ public:
+  SceneViewRegistry(const SceneViewRegistry&) = delete;
+  SceneViewRegistry& operator=(const SceneViewRegistry&) = delete;
+
+  SceneViewRegistry() = default;
+  ~SceneViewRegistry() = default;
+
+  SceneViewHandle create(const SceneView& view = {}) {
+    isRenderQueueDirty = true;
+    return pool.create(view);
+  }
+
+  const SceneView& get(SceneViewHandle handle) const {
+    return pool.get(handle);
+  }
+
+  SceneView& get(SceneViewHandle handle) {
+    isRenderQueueDirty = true;
+    return pool.get(handle);
+  }
+
+  void release(SceneViewHandle handle) {
+    isRenderQueueDirty = true;
+    pool.release(handle);
+  }
+
+  bool isAlive(SceneViewHandle handle) const { return pool.isAlive(handle); }
+
+  u32 size() const { return pool.size(); }
+
+  template <typename Fn>
+  void forEach(Fn&& fn) {
+    isRenderQueueDirty = true;
+    pool.forEach(std::forward<Fn>(fn));
+  }
+
+  template <typename Fn>
+  void forEach(Fn&& fn) const {
+    pool.forEach(std::forward<Fn>(fn));
+  }
+
+  const std::vector<SceneViewHandle>& GetRenderQueue() const {
+    if (isRenderQueueDirty) {
+      rebuildRenderQueue();
+    }
+    return renderQueue;
+  }
+
+ private:
+  void rebuildRenderQueue() const {
+    renderQueue.clear();
+    pool.forEachWithHandle([&](SceneViewHandle handle, const SceneView& view) {
+      if (view.enabled) {
+        renderQueue.push_back(handle);
+      }
+    });
+
+    std::ranges::stable_sort(renderQueue, {}, [this](SceneViewHandle handle) {
+      return pool.get(handle).priority;
+    });
+    isRenderQueueDirty = false;
+  }
+
+  Pool<SceneView> pool{"SceneView"};
+
+  mutable std::vector<SceneViewHandle> renderQueue;
+  mutable bool isRenderQueueDirty = true;
+};
+
+}  // namespace sophia