engine/include/sophia/scene.hpp

@@ -13,18 +13,17 @@ class Scene {
   Scene();
   ~Scene();
 
-  // Every entity gets a TagComponent (named `name`) and a TransformComponent.
   Entity createEntity(const std::string& name = {});
   void destroyEntity(Entity entity);
 
+  Entity createCamera(const std::string& name = "Camera");
+
   /** Calls `fn(Entity)` for every live entity. Defined in entity.hpp. */
   template <typename Fn>
   void forEachEntity(Fn&& fn);
 
-  // The camera a render request uses when it doesn't name one. Null until
+  Entity getActiveCamera();
-  // set.
+  void setActiveCamera(Entity camera);
-  entt::entity getActiveCamera() const { return activeCamera; }
-  void setActiveCamera(entt::entity camera) { activeCamera = camera; }
 
  private:
   friend class Entity;

engine/include/sophia/scene_view.hpp

@@ -17,8 +17,9 @@ enum class ClearFlags : u8 {
 
 struct SceneView {
   SceneHandle scene = INVALID_HANDLE;
-  RenderTargetHandle target = INVALID_HANDLE;
+  RenderTargetHandle target =
-  Entity camera;
+      INVALID_HANDLE;  // null implies render to swapchain
+  Entity camera;       // null implies use scene's active camera
 
   vec4 viewport{0.0f, 0.0f, 1.0f, 1.0f};
 

engine/src/rendering/imgui_renderer.cpp

@@ -91,12 +91,13 @@ void ImGuiRenderer::beginFrame() {
 }
 
 ImTextureID ImGuiRenderer::getTextureId(RenderTargetHandle handle) {
-  vk::ImageView view =
+  const RenderTarget& target = resources.renderTargetPool.get(handle);
-      resources.renderTargetPool.get(handle).getImage().getView();
+  vk::ImageView view = target.getImage().getView();
 
   auto it = textures.find(handle.index);
   if (it != textures.end()) {
-    if (it->second.generation == handle.generation && it->second.view == view) {
+    if (it->second.generation == handle.generation &&
+        it->second.version == target.getVersion()) {
       return (ImTextureID)it->second.descriptorSet;
     }
     ImGui_ImplVulkan_RemoveTexture(it->second.descriptorSet);
@@ -107,7 +108,8 @@ ImTextureID ImGuiRenderer::getTextureId(RenderTargetHandle handle) {
   // left in once the scene pass has finished.
   VkDescriptorSet descriptorSet = ImGui_ImplVulkan_AddTexture(
       static_cast<VkImageView>(view), VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL);
-  textures[handle.index] = {handle.generation, view, descriptorSet};
+  textures[handle.index] = {handle.generation, target.getVersion(),
+                            descriptorSet};
   return (ImTextureID)descriptorSet;
 }
 
@@ -120,7 +122,7 @@ void ImGuiRenderer::releaseStaleTextures() {
 
     bool stale =
         !renderTargetPool.isAlive(handle) ||
-        renderTargetPool.get(handle).getImage().getView() != it->second.view;
+        renderTargetPool.get(handle).getVersion() != it->second.version;
     if (stale) {
       ImGui_ImplVulkan_RemoveTexture(it->second.descriptorSet);
       it = textures.erase(it);

engine/src/rendering/imgui_renderer.hpp

@@ -37,7 +37,7 @@ class ImGuiRenderer {
 
   struct Texture {
     u32 generation;
-    vk::ImageView view;
+    u32 version;
     VkDescriptorSet descriptorSet;
   };
 

engine/src/resources/render_target.cpp

@@ -39,6 +39,7 @@ void RenderTarget::applyPendingResize() {
 }
 
 void RenderTarget::create(u32 width, u32 height) {
+  this->version++;
   this->image = Image::Builder(this->device)
                     .setExtent(width, height)
                     .setFormat(this->format)

engine/src/resources/render_target.hpp

@@ -27,6 +27,7 @@ class RenderTarget {
   Image& getImage() const { return *this->image; }
 
   vk::Extent2D getExtent() const;
+  u32 getVersion() const { return this->version; }
 
   void requestResize(u32 width, u32 height);
 
@@ -46,6 +47,7 @@ class RenderTarget {
   std::unique_ptr<Image> image;
 
   std::optional<vk::Extent2D> pendingExtent;
+  u32 version = 0;
 };
 
 }  // namespace sophia

engine/src/scene/scene.cpp

@@ -16,6 +16,24 @@ Entity Scene::createEntity(const std::string& name) {
   return entity;
 }
 
+Entity Scene::createCamera(const std::string& name) {
+  Entity camera = createEntity(name);
+  camera.addComponent<CameraComponent>();
+  if (this->activeCamera == entt::null) {
+    this->activeCamera = camera;
+  }
+  return camera;
+}
+
+Entity Scene::getActiveCamera() {
+  if (this->activeCamera == entt::null) {
+    return {};
+  }
+  return {this->activeCamera, this};
+}
+
+void Scene::setActiveCamera(Entity camera) { this->activeCamera = camera; }
+
 void Scene::destroyEntity(Entity entity) {
   if (this->activeCamera == entity) {
     this->activeCamera = entt::null;

examples/boids_2d/main.cpp

@@ -87,6 +87,8 @@ class Boids2D : public sophia::Application {
         [this](sophia::KeyReleasedEvent& e) {
           setScrollKeyHeld(e.getKeyCode(), false);
         });
+
+    debugUI().show();
   }
 
   void onCreate() override {
@@ -110,8 +112,7 @@ class Boids2D : public sophia::Application {
     sceneHandle = scenes().create();
     sophia::Scene& scene = scenes().get(sceneHandle);
 
-    cameraEntity = scene.createEntity("Camera");
+    cameraEntity = scene.createCamera();
-    cameraEntity.addComponent<sophia::CameraComponent>();
 
     std::uniform_real_distribution<float> tint{0.0f, 1.0f};
     for (Boid& boid : boids) {
@@ -127,7 +128,6 @@ class Boids2D : public sophia::Application {
     target = resources().create<sophia::RenderTarget>();
     views().create({.scene = sceneHandle,
                     .target = target,
-                    .camera = cameraEntity,
                     .clearColor = {0.01f, 0.01f, 0.02f, 1.0f}});
 
     panels().emplace<ViewportPanel>(ui(), target);

examples/image_viewer/main.cpp

@@ -40,8 +40,7 @@ class ImageViewer : public sophia::Application {
     sophia::SceneHandle sceneHandle = scenes().create();
     sophia::Scene& scene = scenes().get(sceneHandle);
 
-    camera = scene.createEntity("Camera");
+    camera = scene.createCamera();
-    camera.addComponent<sophia::CameraComponent>();
 
     sophia::TextureHandle texture = resources().load<sophia::Texture>(path);
     imageSize = resources().getExtent(texture);
@@ -54,7 +53,6 @@ class ImageViewer : public sophia::Application {
     target = resources().create<sophia::RenderTarget>();
     views().create({.scene = sceneHandle,
                     .target = target,
-                    .camera = camera,
                     .clearColor = {0.1f, 0.1f, 0.15f, 1.f}});
 
     panels().emplace<ViewportPanel>(ui(), target);