Update ImGui to docking branch

.gitmodules

@@ -44,6 +44,7 @@
 [submodule "destrum/third_party/imgui"]
 	path = destrum/third_party/imgui
 	url = https://github.com/ocornut/imgui.git
+	branch = docking
 [submodule "destrum/third_party/jolt"]
 	path = destrum/third_party/jolt
 	url = https://github.com/jrouwe/JoltPhysics.git

destrum/CMakeLists.txt

@@ -37,12 +37,16 @@ set(SRC_FILES
         "src/Graphics/Managers/MemoryManager.cpp"
         "src/Graphics/Managers/FrameManager.cpp"
         "src/Graphics/Managers/ImageManager.cpp"
+        "src/Graphics/Managers/LineRenderingManager.cpp"
+        "src/Graphics/Managers/QuadRenderingManager.cpp"
 
         "src/Graphics/Resources/GPUImage.cpp"
         "src/Graphics/Resources/NBuffer.cpp"
         "src/Graphics/Resources/Cubemap.cpp"
 
         "src/Graphics/Pipelines/MeshPipeline.cpp"
+        "src/Graphics/Pipelines/LineRenderingPass.cpp"
+        "src/Graphics/Pipelines/QuadRendererPass.cpp"
         "src/Graphics/Pipelines/SkyboxPipeline.cpp"
         "src/Graphics/Pipelines/SkinningPipeline.cpp"
         "src/Graphics/Pipelines/ImguiPass.cpp"

destrum/assets_src/shaders/line.frag

@@ -0,0 +1,9 @@
+#version 460
+
+layout (location = 0) in vec4 inColor;
+layout (location = 0) out vec4 outFragColor;
+
+void main()
+{
+    outFragColor = inColor;
+}

destrum/assets_src/shaders/line.vert

@@ -0,0 +1,16 @@
+#version 460
+
+layout (location = 0) in vec4 inPosition;
+layout (location = 1) in vec4 inColor;
+
+layout (location = 0) out vec4 outColor;
+
+layout (push_constant) uniform LinePushConstants {
+    mat4 viewProjection;
+} pcs;
+
+void main()
+{
+    gl_Position = pcs.viewProjection * inPosition;
+    outColor = inColor;
+}

destrum/assets_src/shaders/quad.frag

@@ -0,0 +1,16 @@
+#version 460
+#extension GL_GOOGLE_include_directive : require
+#extension GL_EXT_nonuniform_qualifier : enable
+
+#include "bindless.glsl"
+
+layout(location = 0) in vec2 inUV;
+layout(location = 1) in vec4 inColor;
+layout(location = 2) flat in uint inTexId;
+
+layout(location = 0) out vec4 outFragColor;
+
+void main() {
+    vec4 texColor = sampleTexture2DLinear(inTexId, inUV);
+    outFragColor = texColor * inColor;
+}

destrum/assets_src/shaders/quad.vert

@@ -0,0 +1,22 @@
+#version 460
+#extension GL_GOOGLE_include_directive : require
+
+layout(location = 0) in vec2 inPosition;
+layout(location = 1) in vec2 inUV;
+layout(location = 2) in vec4 inColor;
+layout(location = 3) in uint inTexId;
+
+layout(location = 0) out vec2 outUV;
+layout(location = 1) out vec4 outColor;
+layout(location = 2) flat out uint outTexId;
+
+layout(push_constant) uniform QuadPushConstants {
+    mat4 viewProjection;
+} pcs;
+
+void main() {
+    gl_Position = pcs.viewProjection * vec4(inPosition, 0.0, 1.0);
+    outUV = inUV;
+    outColor = inColor;
+    outTexId = inTexId;
+}

destrum/include/destrum/Graphics/Managers/LineRenderingManager.h

@@ -0,0 +1,37 @@
+#ifndef DESTRUM_LINERENDERINGMANAGER_H
+#define DESTRUM_LINERENDERINGMANAGER_H
+
+#include <vector>
+
+#include <glm/vec3.hpp>
+#include <glm/vec4.hpp>
+
+#include <destrum/Singleton.h>
+
+struct Line {
+    glm::vec3 start{};
+    glm::vec3 end{};
+    glm::vec4 color{1.0f};
+};
+
+class LineRenderingManager final : public Singleton<LineRenderingManager> {
+public:
+    friend class Singleton<LineRenderingManager>;
+
+    void SubmitLine(const Line& line);
+    void SubmitLine(
+        const glm::vec3& start,
+        const glm::vec3& end,
+        const glm::vec4& color = glm::vec4{1.0f});
+
+    [[nodiscard]] const std::vector<Line>& GetLines() const { return lines; }
+
+    void ClearLines();
+
+private:
+    LineRenderingManager() = default;
+
+    std::vector<Line> lines;
+};
+
+#endif // DESTRUM_LINERENDERINGMANAGER_H

destrum/include/destrum/Graphics/Managers/QuadRenderingManager.h

@@ -0,0 +1,45 @@
+#ifndef DESTRUM_QUADRENDERINGMANAGER_H
+#define DESTRUM_QUADRENDERINGMANAGER_H
+
+#include <vector>
+
+#include <glm/glm.hpp>
+
+#include <destrum/Graphics/ids.h>
+#include <destrum/Singleton.h>
+
+struct QuadSubmission {
+    glm::vec2 position;
+    glm::vec2 size;
+    float rotation;
+    glm::vec4 color;
+    ImageID textureId;
+};
+
+class QuadRenderingManager final : public Singleton<QuadRenderingManager> {
+public:
+    friend class Singleton<QuadRenderingManager>;
+
+    void SubmitQuad(
+        const glm::vec2& position,
+        const glm::vec2& size,
+        const glm::vec4& color = glm::vec4{1.0f},
+        ImageID textureId = NULL_IMAGE_ID);
+
+    void SubmitQuad(
+        const glm::vec2& position,
+        const glm::vec2& size,
+        float rotation,
+        const glm::vec4& color = glm::vec4{1.0f},
+        ImageID textureId = NULL_IMAGE_ID);
+
+    [[nodiscard]] const std::vector<QuadSubmission>& GetQuads() const { return quads; }
+    void ClearQuads();
+
+private:
+    QuadRenderingManager() = default;
+
+    std::vector<QuadSubmission> quads;
+};
+
+#endif // DESTRUM_QUADRENDERINGMANAGER_H

destrum/include/destrum/Graphics/Pipelines/LineRenderingPass.h

@@ -0,0 +1,42 @@
+#ifndef DESTRUM_LINERENDERINGPASS_H
+#define DESTRUM_LINERENDERINGPASS_H
+
+#include <cstddef>
+#include <memory>
+
+#include <vulkan/vulkan.h>
+
+#include <destrum/Graphics/Managers/LineRenderingManager.h>
+#include <destrum/Graphics/Resources/NBuffer.h>
+
+class Camera;
+class GfxDevice;
+struct GPUImage;
+class Pipeline;
+
+class LineRenderingPass final {
+public:
+    void init(GfxDevice& gfxDevice, VkFormat drawImageFormat);
+    void draw(
+        VkCommandBuffer cmd,
+        GfxDevice& gfxDevice,
+        const GPUImage& target,
+        const Camera& camera,
+        LineRenderingManager& lineManager);
+    void cleanup(GfxDevice& gfxDevice);
+
+private:
+    struct LineVertex {
+        glm::vec4 position;
+        glm::vec4 color;
+    };
+
+    void ensureVertexCapacity(GfxDevice& gfxDevice, std::size_t requiredVertices);
+
+    VkPipelineLayout pipelineLayout{VK_NULL_HANDLE};
+    std::unique_ptr<Pipeline> pipeline;
+    NBuffer vertexBuffer;
+    std::size_t vertexCapacity{0};
+};
+
+#endif // DESTRUM_LINERENDERINGPASS_H

destrum/include/destrum/Graphics/Pipelines/QuadRendererPass.h

@@ -0,0 +1,47 @@
+#ifndef DESTRUM_QUADRENDERERPASS_H
+#define DESTRUM_QUADRENDERERPASS_H
+
+#include <cstddef>
+#include <memory>
+
+#include <glm/glm.hpp>
+
+#include <vulkan/vulkan.h>
+
+#include <destrum/Graphics/Resources/Buffer.h>
+
+
+class GfxDevice;
+class Pipeline;
+struct GPUImage;
+class RenderResources;
+
+class QuadRendererPass final {
+public:
+    void init(GfxDevice& gfxDevice, RenderResources& resources, VkFormat drawImageFormat);
+    void draw(
+        VkCommandBuffer cmd,
+        GfxDevice& gfxDevice,
+        RenderResources& resources,
+        const GPUImage& target,
+        const glm::mat4& projection);
+    void cleanup(GfxDevice& gfxDevice);
+
+private:
+    struct QuadVertex {
+        glm::vec2 position;
+        glm::vec2 uv;
+        glm::vec4 color;
+        std::uint32_t textureId;
+    };
+
+    void ensureCapacity(GfxDevice& gfxDevice, std::size_t requiredQuads);
+
+    VkPipelineLayout pipelineLayout{VK_NULL_HANDLE};
+    std::unique_ptr<Pipeline> pipeline;
+    GPUBuffer vertexBuffer{};
+    GPUBuffer indexBuffer{};
+    std::size_t quadCapacity{0};
+};
+
+#endif // DESTRUM_QUADRENDERERPASS_H

destrum/include/destrum/Graphics/Renderer.h

@@ -1,10 +1,13 @@
 #ifndef RENDERER_H
 #define RENDERER_H
 
+#include <glm/mat4x4.hpp>
 #include <glm/vec3.hpp>
 
 #include <destrum/Graphics/Camera.h>
+#include <destrum/Graphics/Pipelines/LineRenderingPass.h>
 #include <destrum/Graphics/Pipelines/MeshPipeline.h>
+#include <destrum/Graphics/Pipelines/QuadRendererPass.h>
 #include <destrum/Graphics/ids.h>
 #include <destrum/Graphics/MeshDrawCommand.h>
 #include <destrum/Graphics/Resources/NBuffer.h>
@@ -68,6 +71,11 @@ public:
         return resources;
     }
 
+    void drawQuads(
+        VkCommandBuffer cmd,
+        GfxDevice& gfxDevice,
+        const glm::mat4& projection);
+
 private:
     void createDrawImage(GfxDevice& gfxDevice, const glm::ivec2& drawImageSize, bool firstCreate);
 
@@ -111,6 +119,8 @@ private:
 
     std::unique_ptr<MeshPipeline> meshPipeline;
     std::unique_ptr<SkyboxPipeline> skyboxPipeline;
+    std::unique_ptr<LineRenderingPass> lineRenderingPass;
+    std::unique_ptr<QuadRendererPass> quadRendererPass;
 
     std::unique_ptr<SkinningPipeline> skinningPipeline;
     bool initialized{false};

destrum/include/destrum/Input/InputManager.h

@@ -30,8 +30,8 @@ public:
 
     int MouseX() const { return m_mouseX; }
     int MouseY() const { return m_mouseY; }
-    int MouseDeltaX() const { return m_mouseDX; }
-    int MouseDeltaY() const { return m_mouseDY; }
+    int MouseDeltaX() const { return m_mouseRelDX; }
+    int MouseDeltaY() const { return m_mouseRelDY; }
 
     int WheelX() const { return m_wheelX; }
     int WheelY() const { return m_wheelY; }
@@ -81,6 +81,9 @@ public:
 
     void SetAxisDeadzone(int deadzone) { m_axisDeadzone = deadzone; } // 0..32767
 
+    void SetMouseCaptured(bool captured);
+    [[nodiscard]] bool IsMouseCaptured() const { return m_MouseCaptured; }
+
 private:
     // Key states
     std::unordered_set<SDL_Scancode> m_keysDown;
@@ -92,10 +95,9 @@ private:
     std::unordered_set<Uint8> m_mousePressed;
     std::unordered_set<Uint8> m_mouseReleased;
 
-    // Mouse position + delta
+    // Mouse position + relative delta (accumulated from SDL xrel/yrel)
     int m_mouseX = 0, m_mouseY = 0;
-    int m_prevMouseX = 0, m_prevMouseY = 0;
-    int m_mouseDX = 0, m_mouseDY = 0;
+    int m_mouseRelDX = 0, m_mouseRelDY = 0;
 
     int m_wheelX = 0, m_wheelY = 0;
 
@@ -125,6 +127,8 @@ private:
 
     int m_axisDeadzone = 8000; // typical deadzone
 
+    bool m_MouseCaptured = false;
+
 private:
     bool QueryBinding(const Binding& b, ButtonState state) const;
 

destrum/include/destrum/ObjectModel/Component.h

@@ -59,6 +59,16 @@ public:
     virtual void ResolveReferences(const ObjectMap&) {
     }
 
+    // Trigger callbacks called when this component's owner overlaps a sensor.
+    // Only called when the owner has a Collider set as a trigger (or overlaps one).
+    virtual void OnTriggerEnter(GameObject* other) {
+        (void)other;
+    }
+
+    virtual void OnTriggerExit(GameObject* other) {
+        (void)other;
+    }
+
     bool HasStarted{false};
 
 protected:

destrum/include/destrum/Physics/JoltPhysicsWorld.h

@@ -55,6 +55,8 @@ public:
                  float maxDistance,
                  PhysicsRaycastHit& hit) const override;
 
+    std::vector<TriggerEvent> ConsumeTriggerEvents() override;
+
 private:
     class Impl;
     std::unique_ptr<Impl> m_Impl;

destrum/include/destrum/Physics/PhysicsSceneBridge.h

@@ -21,6 +21,7 @@ class PhysicsSceneBridge final {
 public:
     explicit PhysicsSceneBridge(std::unique_ptr<PhysicsWorld> world);
 
+    [[nodiscard]] bool IsValid() const { return m_World != nullptr; }
     [[nodiscard]] PhysicsWorld& GetWorld() { return *m_World; }
     [[nodiscard]] const PhysicsWorld& GetWorld() const { return *m_World; }
 

destrum/include/destrum/Physics/PhysicsTypes.h

@@ -116,3 +116,9 @@ struct PhysicsBodyDesc {
     bool useGravity{true};
     bool allowSleep{true};
 };
+
+struct TriggerEvent {
+    GameObject* owner{nullptr};
+    GameObject* other{nullptr};
+    bool entered{true};
+};

destrum/include/destrum/Physics/PhysicsWorld.h

@@ -1,5 +1,7 @@
 #pragma once
 
+#include <vector>
+
 #include <glm/glm.hpp>
 
 #include <unordered_set>
@@ -49,6 +51,9 @@ public:
                          float maxDistance,
                          PhysicsRaycastHit& hit) const = 0;
 
+    // Trigger events accumulated during the last Step().
+    virtual std::vector<TriggerEvent> ConsumeTriggerEvents() { return {}; }
+
 private:
     std::unordered_set<Rigidbody*> m_RegisteredRigidbodies;
 };

destrum/include/destrum/Scene/Scene.h

@@ -3,6 +3,8 @@
 
 #include <functional>
 
+#include <memory>
+
 #include <destrum/Event.h>
 #include <destrum/ObjectModel/ObjectId.h>
 #include <destrum/Scene/SceneManager.h>
@@ -12,6 +14,7 @@
 
 class GameObject;
 class SceneSerializer;
+class PhysicsWorld;
 
 class Scene final {
     friend Scene& SceneManager::CreateScene(const std::string& name);
@@ -104,6 +107,7 @@ public:
     PhysicsSceneBridge& GetPhysics() { return m_Physics; }
 private:
     explicit Scene(const std::string& name);
+    explicit Scene(const std::string& name, std::unique_ptr<PhysicsWorld> physicsWorld);
 
     PhysicsSceneBridge m_Physics{std::make_unique<JoltPhysicsWorld>()};
 

destrum/include/destrum/Scene/SceneManager.h

@@ -16,6 +16,7 @@ public:
     Scene& CreateScene(const std::string& name);
 
     Scene& GetCurrentScene() const;
+    const std::vector<std::shared_ptr<Scene>>& GetActiveScenes() const { return m_activeScenes; }
 
     void Update(float dt);
     void FixedUpdate(float dt);
@@ -34,7 +35,9 @@ public:
     void Destroy();
 
     void SwitchScene(int index);
-    int GetActiveSceneId() const { return m_scenes.empty() ? -1 : m_ActiveSceneIndex; }
+    void AddActiveScene(int index);
+    void RemoveActiveScene(int index);
+    int GetActiveSceneId() const;
 
     [[nodiscard]] const std::vector<std::shared_ptr<Scene>>& GetScenes() const { return m_scenes; }
 
@@ -47,8 +50,7 @@ private:
 
     SceneManager() = default;
 
-    int m_ActiveSceneIndex{0};
-
+    std::vector<std::shared_ptr<Scene>> m_activeScenes;
     std::vector<std::shared_ptr<Scene>> m_scenes;
 };
 

destrum/include/destrum/Serialization/EngineComponentList.h

@@ -22,6 +22,6 @@
     X(Rigidbody) \
     X(BoxCollider) \
     X(SphereCollider) \
-    X(CapsuleCollider)
+    X(CapsuleCollider) \
 
 #endif // DESTRUM_ENGINECOMPONENTLIST_H

destrum/include/destrum/Serialization/SceneSerializer.h

@@ -2,13 +2,37 @@
 #define DESTRUM_SCENESERIALIZER_H
 
 #include <filesystem>
+#include <functional>
+#include <future>
+
+#include <nlohmann/json.hpp>
 
 class Scene;
 
 class SceneSerializer final {
 public:
+    struct LoadResult {
+        bool success{false};
+        std::string errorMessage;
+        nlohmann::json root;
+    };
+
     static bool Save(Scene& scene, const std::filesystem::path& path);
-    static bool Load(Scene& scene, const std::filesystem::path& path);
+
+    static bool Load(Scene& scene, const std::filesystem::path& path,
+                     std::function<void(float)> progressCallback = nullptr);
+
+    // Thread-safe: parse and validate a scene file on any thread.
+    // No engine state is touched during parsing.
+    static LoadResult LoadSceneFile(const std::filesystem::path& path);
+
+    // Main-thread-only: construct a scene from pre-validated JSON.
+    static bool ConstructScene(Scene& scene, LoadResult& result,
+                               std::function<void(float)> progressCallback = nullptr);
+
+    // Parse the scene file on a background thread. Call LoadFromJson on the
+    // main thread once the future is ready.
+    static std::future<LoadResult> LoadSceneFileAsync(const std::filesystem::path& path);
 };
 
 #endif //DESTRUM_SCENESERIALIZER_H

destrum/src/App.cpp

@@ -131,6 +131,12 @@ void App::run()
 
                 imguiPass.handleEvent(event);
 
+                const bool mouseEvent =
+                    event.type == SDL_MOUSEBUTTONDOWN ||
+                    event.type == SDL_MOUSEBUTTONUP ||
+                    event.type == SDL_MOUSEMOTION ||
+                    event.type == SDL_MOUSEWHEEL;
+
                 if (event.type == SDL_QUIT)
                 {
                     isRunning = false;
@@ -149,19 +155,13 @@ void App::run()
                     }
                 }
 
-                const bool mouseEvent =
-                    event.type == SDL_MOUSEBUTTONDOWN ||
-                    event.type == SDL_MOUSEBUTTONUP ||
-                    event.type == SDL_MOUSEMOTION ||
-                    event.type == SDL_MOUSEWHEEL;
-
                 const bool keyboardEvent =
                     event.type == SDL_KEYDOWN ||
                     event.type == SDL_KEYUP ||
                     event.type == SDL_TEXTINPUT;
 
                 const bool capturedByImgui =
-                    (mouseEvent && imguiPass.wantsMouse()) ||
+                    (mouseEvent && !InputManager::GetInstance().IsMouseCaptured() && imguiPass.wantsMouse()) ||
                     (keyboardEvent && imguiPass.wantsKeyboard());
 
                 if (!capturedByImgui)

destrum/src/Graphics/Camera.cpp

@@ -114,7 +114,7 @@ void Camera::SetRotation(const glm::vec2& yawPitchRadians) {
     SetRotation(yawPitchRadians.x, yawPitchRadians.y);
 }
 
-void Camera::SetTarget(const glm::vec3& target) {
+void Camera::SetTarget(const glm::vec3&) {
 }
 
 void Camera::ClearTarget() {

destrum/src/Graphics/Managers/LineRenderingManager.cpp

@@ -0,0 +1,23 @@
+#include <destrum/Graphics/Managers/LineRenderingManager.h>
+
+void LineRenderingManager::SubmitLine(const Line& line)
+{
+    lines.push_back(line);
+}
+
+void LineRenderingManager::SubmitLine(
+    const glm::vec3& start,
+    const glm::vec3& end,
+    const glm::vec4& color)
+{
+    SubmitLine(Line{
+        .start = start,
+        .end = end,
+        .color = color,
+    });
+}
+
+void LineRenderingManager::ClearLines()
+{
+    lines.clear();
+}

destrum/src/Graphics/Managers/QuadRenderingManager.cpp

@@ -0,0 +1,31 @@
+#include <destrum/Graphics/Managers/QuadRenderingManager.h>
+
+void QuadRenderingManager::SubmitQuad(
+    const glm::vec2& position,
+    const glm::vec2& size,
+    const glm::vec4& color,
+    ImageID textureId)
+{
+    SubmitQuad(position, size, 0.0f, color, textureId);
+}
+
+void QuadRenderingManager::SubmitQuad(
+    const glm::vec2& position,
+    const glm::vec2& size,
+    float rotation,
+    const glm::vec4& color,
+    ImageID textureId)
+{
+    quads.push_back(QuadSubmission{
+        .position = position,
+        .size = size,
+        .rotation = rotation,
+        .color = color,
+        .textureId = textureId,
+    });
+}
+
+void QuadRenderingManager::ClearQuads()
+{
+    quads.clear();
+}

destrum/src/Graphics/Pipelines/ImguiPass.cpp

@@ -124,6 +124,11 @@ void ImguiPass::beginFrame() {
 
     ImGui_ImplVulkan_NewFrame();
     ImGui_ImplSDL2_NewFrame();
+
+    if (SDL_GetRelativeMouseMode() == SDL_TRUE) {
+        ImGui::GetIO().MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
+    }
+
     ImGui::NewFrame();
 
     frameBegun = true;

destrum/src/Graphics/Pipelines/LineRenderingPass.cpp

@@ -0,0 +1,232 @@
+#include <destrum/Graphics/Pipelines/LineRenderingPass.h>
+
+#include <algorithm>
+#include <cstdint>
+#include <limits>
+#include <stdexcept>
+
+#include <destrum/FS/AssetFS.h>
+#include <destrum/Graphics/Camera.h>
+#include <destrum/Graphics/GPUImage.h>
+#include <destrum/Graphics/GfxDevice.h>
+#include <destrum/Graphics/Pipeline.h>
+#include <destrum/Graphics/Util.h>
+
+#include "volk.h"
+
+namespace {
+    constexpr std::size_t InitialVertexCapacity = 256;
+}
+
+void LineRenderingPass::init(GfxDevice& gfxDevice, VkFormat drawImageFormat)
+{
+    try {
+        vertexBuffer.init(
+            gfxDevice,
+            VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+            InitialVertexCapacity * sizeof(LineVertex),
+            "line vertices");
+        vertexCapacity = InitialVertexCapacity;
+
+        const auto vertexShader =
+            AssetFS::GetInstance().GetCookedPathForFile("engine://shaders/line.vert");
+        const auto fragmentShader =
+            AssetFS::GetInstance().GetCookedPathForFile("engine://shaders/line.frag");
+
+        const auto pushConstantRange = VkPushConstantRange{
+            .stageFlags = VK_SHADER_STAGE_VERTEX_BIT,
+            .offset = 0,
+            .size = sizeof(glm::mat4),
+        };
+
+        const auto pipelineLayoutInfo = VkPipelineLayoutCreateInfo{
+            .sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO,
+            .pushConstantRangeCount = 1,
+            .pPushConstantRanges = &pushConstantRange,
+        };
+
+        VK_CHECK(vkCreatePipelineLayout(
+            gfxDevice.getDevice(),
+            &pipelineLayoutInfo,
+            nullptr,
+            &pipelineLayout));
+
+        PipelineConfigInfo pipelineConfig{};
+        Pipeline::DefaultPipelineConfigInfo(pipelineConfig);
+        pipelineConfig.name = "Line Rendering Pipeline";
+        pipelineConfig.pipelineLayout = pipelineLayout;
+        pipelineConfig.inputAssemblyInfo.topology = VK_PRIMITIVE_TOPOLOGY_LINE_LIST;
+        pipelineConfig.rasterizationInfo.cullMode = VK_CULL_MODE_NONE;
+        pipelineConfig.depthStencilInfo.depthTestEnable = VK_FALSE;
+        pipelineConfig.depthStencilInfo.depthWriteEnable = VK_FALSE;
+        pipelineConfig.depthStencilInfo.depthCompareOp = VK_COMPARE_OP_ALWAYS;
+        pipelineConfig.colorAttachments = {drawImageFormat};
+        pipelineConfig.depthAttachment = VK_FORMAT_UNDEFINED;
+
+        pipelineConfig.vertexBindingDescriptions = {
+            VkVertexInputBindingDescription{
+                .binding = 0,
+                .stride = sizeof(LineVertex),
+                .inputRate = VK_VERTEX_INPUT_RATE_VERTEX,
+            }
+        };
+        pipelineConfig.vertexAttributeDescriptions = {
+            VkVertexInputAttributeDescription{
+                .location = 0,
+                .binding = 0,
+                .format = VK_FORMAT_R32G32B32A32_SFLOAT,
+                .offset = offsetof(LineVertex, position),
+            },
+            VkVertexInputAttributeDescription{
+                .location = 1,
+                .binding = 0,
+                .format = VK_FORMAT_R32G32B32A32_SFLOAT,
+                .offset = offsetof(LineVertex, color),
+            },
+        };
+
+        pipelineConfig.colorBlendAttachment.blendEnable = VK_TRUE;
+        pipelineConfig.colorBlendAttachment.srcColorBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
+        pipelineConfig.colorBlendAttachment.dstColorBlendFactor =
+            VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
+        pipelineConfig.colorBlendAttachment.colorBlendOp = VK_BLEND_OP_ADD;
+        pipelineConfig.colorBlendAttachment.srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE;
+        pipelineConfig.colorBlendAttachment.dstAlphaBlendFactor =
+            VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
+        pipelineConfig.colorBlendAttachment.alphaBlendOp = VK_BLEND_OP_ADD;
+
+        pipeline = std::make_unique<Pipeline>(
+            gfxDevice,
+            vertexShader.string(),
+            fragmentShader.string(),
+            pipelineConfig);
+    } catch (...) {
+        cleanup(gfxDevice);
+        throw;
+    }
+}
+
+void LineRenderingPass::draw(
+    VkCommandBuffer cmd,
+    GfxDevice& gfxDevice,
+    const GPUImage& target,
+    const Camera& camera,
+    LineRenderingManager& lineManager)
+{
+    const auto& lines = lineManager.GetLines();
+    if (!pipeline || lines.empty()) {
+        lineManager.ClearLines();
+        return;
+    }
+
+    if (lines.size() > std::numeric_limits<std::size_t>::max() / 2) {
+        throw std::overflow_error("Too many lines submitted for rendering");
+    }
+
+    std::vector<LineVertex> vertices;
+    vertices.reserve(lines.size() * 2);
+    for (const Line& line : lines) {
+        vertices.push_back(LineVertex{
+            .position = glm::vec4{line.start, 1.0f},
+            .color = line.color,
+        });
+        vertices.push_back(LineVertex{
+            .position = glm::vec4{line.end, 1.0f},
+            .color = line.color,
+        });
+    }
+
+    if (vertices.size() > std::numeric_limits<std::uint32_t>::max()) {
+        throw std::overflow_error("Too many line vertices submitted for rendering");
+    }
+
+    ensureVertexCapacity(gfxDevice, vertices.size());
+    vertexBuffer.uploadNewData(
+        cmd,
+        gfxDevice.getCurrentFrameIndex(),
+        vertices.data(),
+        vertices.size() * sizeof(LineVertex));
+
+    auto renderInfo = vkutil::createRenderingInfo({
+        .renderExtent = target.getExtent2D(),
+        .colorImageView = target.imageView,
+    });
+
+    vkCmdBeginRendering(cmd, &renderInfo.renderingInfo);
+
+    pipeline->bind(cmd);
+
+    const auto viewport = VkViewport{
+        .x = 0.0f,
+        .y = 0.0f,
+        .width = static_cast<float>(target.extent.width),
+        .height = static_cast<float>(target.extent.height),
+        .minDepth = 0.0f,
+        .maxDepth = 1.0f,
+    };
+    vkCmdSetViewport(cmd, 0, 1, &viewport);
+
+    const auto scissor = VkRect2D{
+        .offset = {},
+        .extent = target.getExtent2D(),
+    };
+    vkCmdSetScissor(cmd, 0, 1, &scissor);
+    vkCmdSetPolygonModeEXT(cmd, VK_POLYGON_MODE_FILL);
+
+    const glm::mat4 viewProjection = camera.GetViewProjectionMatrix();
+    vkCmdPushConstants(
+        cmd,
+        pipelineLayout,
+        VK_SHADER_STAGE_VERTEX_BIT,
+        0,
+        sizeof(viewProjection),
+        &viewProjection);
+
+    const VkBuffer vertexBufferHandle = vertexBuffer.getBuffer().buffer;
+    const VkDeviceSize vertexBufferOffset = 0;
+    vkCmdBindVertexBuffers(cmd, 0, 1, &vertexBufferHandle, &vertexBufferOffset);
+    vkCmdDraw(cmd, static_cast<std::uint32_t>(vertices.size()), 1, 0, 0);
+
+    vkCmdEndRendering(cmd);
+    lineManager.ClearLines();
+}
+
+void LineRenderingPass::cleanup(GfxDevice& gfxDevice)
+{
+    pipeline.reset();
+
+    if (pipelineLayout != VK_NULL_HANDLE && gfxDevice.getDevice() != VK_NULL_HANDLE) {
+        vkDestroyPipelineLayout(gfxDevice.getDevice(), pipelineLayout, nullptr);
+    }
+    pipelineLayout = VK_NULL_HANDLE;
+
+    vertexBuffer.cleanup(gfxDevice);
+    vertexCapacity = 0;
+}
+
+void LineRenderingPass::ensureVertexCapacity(
+    GfxDevice& gfxDevice,
+    std::size_t requiredVertices)
+{
+    if (requiredVertices <= vertexCapacity) {
+        return;
+    }
+
+    std::size_t newCapacity = std::max(vertexCapacity, InitialVertexCapacity);
+    while (newCapacity < requiredVertices) {
+        if (newCapacity > std::numeric_limits<std::size_t>::max() / 2) {
+            newCapacity = requiredVertices;
+            break;
+        }
+        newCapacity *= 2;
+    }
+
+    gfxDevice.waitIdle();
+    vertexBuffer.cleanup(gfxDevice);
+    vertexBuffer.init(
+        gfxDevice,
+        VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+        newCapacity * sizeof(LineVertex),
+        "line vertices");
+    vertexCapacity = newCapacity;
+}

destrum/src/Graphics/Pipelines/QuadRendererPass.cpp

@@ -0,0 +1,334 @@
+#include <destrum/Graphics/Pipelines/QuadRendererPass.h>
+
+#include <algorithm>
+#include <array>
+#include <cmath>
+#include <cstdint>
+#include <cstring>
+#include <limits>
+#include <stdexcept>
+
+#include <glm/glm.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+
+#include <destrum/FS/AssetFS.h>
+#include <destrum/Graphics/GfxDevice.h>
+#include <destrum/Graphics/GPUImage.h>
+#include <destrum/Graphics/Pipeline.h>
+#include <destrum/Graphics/RenderResources.h>
+#include <destrum/Graphics/Util.h>
+#include <destrum/Graphics/Managers/QuadRenderingManager.h>
+
+#include "volk.h"
+
+namespace {
+    constexpr std::size_t InitialQuadCapacity = 256;
+    constexpr std::size_t VerticesPerQuad = 4;
+    constexpr std::size_t IndicesPerQuad = 6;
+
+    glm::vec2 rotatePoint(const glm::vec2& point, float cosA, float sinA) {
+        return glm::vec2{
+            point.x * cosA - point.y * sinA,
+            point.x * sinA + point.y * cosA,
+        };
+    }
+}
+
+void QuadRendererPass::init(GfxDevice& gfxDevice, RenderResources& resources, VkFormat drawImageFormat)
+{
+    try {
+        const std::size_t vertexBytes = InitialQuadCapacity * VerticesPerQuad * sizeof(QuadVertex);
+        vertexBuffer = gfxDevice.createBuffer(
+            vertexBytes,
+            VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+            VMA_MEMORY_USAGE_AUTO_PREFER_HOST);
+
+        const std::size_t indexBytes = InitialQuadCapacity * IndicesPerQuad * sizeof(std::uint32_t);
+        indexBuffer = gfxDevice.createBuffer(
+            indexBytes,
+            VK_BUFFER_USAGE_INDEX_BUFFER_BIT,
+            VMA_MEMORY_USAGE_AUTO_PREFER_HOST);
+
+        quadCapacity = InitialQuadCapacity;
+
+        const auto vertexShader =
+            AssetFS::GetInstance().GetCookedPathForFile("engine://shaders/quad.vert");
+        const auto fragmentShader =
+            AssetFS::GetInstance().GetCookedPathForFile("engine://shaders/quad.frag");
+
+        const auto pushConstantRange = VkPushConstantRange{
+            .stageFlags = VK_SHADER_STAGE_VERTEX_BIT,
+            .offset = 0,
+            .size = sizeof(glm::mat4),
+        };
+
+        const auto layouts = std::array{
+            resources.getBindlessDescSetLayout()
+        };
+
+        const auto pipelineLayoutInfo = VkPipelineLayoutCreateInfo{
+            .sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO,
+            .setLayoutCount = static_cast<std::uint32_t>(layouts.size()),
+            .pSetLayouts = layouts.data(),
+            .pushConstantRangeCount = 1,
+            .pPushConstantRanges = &pushConstantRange,
+        };
+
+        VK_CHECK(vkCreatePipelineLayout(
+            gfxDevice.getDevice(),
+            &pipelineLayoutInfo,
+            nullptr,
+            &pipelineLayout));
+
+        PipelineConfigInfo pipelineConfig{};
+        Pipeline::DefaultPipelineConfigInfo(pipelineConfig);
+        pipelineConfig.name = "Quad Rendering Pipeline";
+        pipelineConfig.pipelineLayout = pipelineLayout;
+        pipelineConfig.inputAssemblyInfo.topology = VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST;
+        pipelineConfig.rasterizationInfo.cullMode = VK_CULL_MODE_NONE;
+        pipelineConfig.depthStencilInfo.depthTestEnable = VK_FALSE;
+        pipelineConfig.depthStencilInfo.depthWriteEnable = VK_FALSE;
+        pipelineConfig.depthStencilInfo.depthCompareOp = VK_COMPARE_OP_ALWAYS;
+        pipelineConfig.colorAttachments = {drawImageFormat};
+        pipelineConfig.depthAttachment = VK_FORMAT_UNDEFINED;
+
+        pipelineConfig.vertexBindingDescriptions = {
+            VkVertexInputBindingDescription{
+                .binding = 0,
+                .stride = sizeof(QuadVertex),
+                .inputRate = VK_VERTEX_INPUT_RATE_VERTEX,
+            }
+        };
+        pipelineConfig.vertexAttributeDescriptions = {
+            VkVertexInputAttributeDescription{
+                .location = 0,
+                .binding = 0,
+                .format = VK_FORMAT_R32G32_SFLOAT,
+                .offset = offsetof(QuadVertex, position),
+            },
+            VkVertexInputAttributeDescription{
+                .location = 1,
+                .binding = 0,
+                .format = VK_FORMAT_R32G32_SFLOAT,
+                .offset = offsetof(QuadVertex, uv),
+            },
+            VkVertexInputAttributeDescription{
+                .location = 2,
+                .binding = 0,
+                .format = VK_FORMAT_R32G32B32A32_SFLOAT,
+                .offset = offsetof(QuadVertex, color),
+            },
+            VkVertexInputAttributeDescription{
+                .location = 3,
+                .binding = 0,
+                .format = VK_FORMAT_R32_UINT,
+                .offset = offsetof(QuadVertex, textureId),
+            },
+        };
+
+        pipelineConfig.colorBlendAttachment.blendEnable = VK_TRUE;
+        pipelineConfig.colorBlendAttachment.srcColorBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
+        pipelineConfig.colorBlendAttachment.dstColorBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
+        pipelineConfig.colorBlendAttachment.colorBlendOp = VK_BLEND_OP_ADD;
+        pipelineConfig.colorBlendAttachment.srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE;
+        pipelineConfig.colorBlendAttachment.dstAlphaBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
+        pipelineConfig.colorBlendAttachment.alphaBlendOp = VK_BLEND_OP_ADD;
+
+        pipeline = std::make_unique<Pipeline>(
+            gfxDevice,
+            vertexShader.string(),
+            fragmentShader.string(),
+            pipelineConfig);
+    } catch (...) {
+        cleanup(gfxDevice);
+        throw;
+    }
+}
+
+void QuadRendererPass::draw(
+    VkCommandBuffer cmd,
+    GfxDevice& gfxDevice,
+    RenderResources& resources,
+    const GPUImage& target,
+    const glm::mat4& projection)
+{
+    auto& quadManager = QuadRenderingManager::GetInstance();
+    const auto& quads = quadManager.GetQuads();
+    if (!pipeline || quads.empty()) {
+        quadManager.ClearQuads();
+        return;
+    }
+
+    const std::size_t numQuads = quads.size();
+    if (numQuads > std::numeric_limits<std::size_t>::max() / VerticesPerQuad) {
+        throw std::overflow_error("Too many quads submitted for rendering");
+    }
+
+    const std::size_t numVertices = numQuads * VerticesPerQuad;
+    const std::size_t numIndices = numQuads * IndicesPerQuad;
+
+    if (numVertices > std::numeric_limits<std::uint32_t>::max()) {
+        throw std::overflow_error("Too many quad vertices submitted for rendering");
+    }
+
+    ensureCapacity(gfxDevice, numQuads);
+
+    const ImageID whiteTextureId = resources.getWhiteTextureID();
+
+    auto* vertexMapped = reinterpret_cast<std::uint8_t*>(vertexBuffer.info.pMappedData);
+    auto* indexMapped = reinterpret_cast<std::uint8_t*>(indexBuffer.info.pMappedData);
+
+    constexpr std::array<glm::vec2, 4> localCorners = {{
+        glm::vec2{-0.5f, -0.5f},
+        glm::vec2{ 0.5f, -0.5f},
+        glm::vec2{ 0.5f,  0.5f},
+        glm::vec2{-0.5f,  0.5f},
+    }};
+
+    constexpr std::array<glm::vec2, 4> uvs = {{
+        glm::vec2{0.0f, 1.0f},
+        glm::vec2{1.0f, 1.0f},
+        glm::vec2{1.0f, 0.0f},
+        glm::vec2{0.0f, 0.0f},
+    }};
+
+    auto* vertWrite = reinterpret_cast<QuadVertex*>(vertexMapped);
+    auto* idxWrite = reinterpret_cast<std::uint32_t*>(indexMapped);
+    std::uint32_t vertexBase = 0;
+
+    for (const auto& quad : quads) {
+        const float cosA = std::cos(quad.rotation);
+        const float sinA = std::sin(quad.rotation);
+        const glm::vec2 halfSize = quad.size * 0.5f;
+        const ImageID texId = (quad.textureId == NULL_IMAGE_ID) ? whiteTextureId : quad.textureId;
+
+        for (std::size_t v = 0; v < VerticesPerQuad; ++v) {
+            glm::vec2 localPos = localCorners[v] * halfSize;
+            glm::vec2 rotatedPos = rotatePoint(localPos, cosA, sinA);
+            glm::vec2 worldPos = quad.position + rotatedPos;
+
+            vertWrite[vertexBase + v] = QuadVertex{
+                .position = worldPos,
+                .uv = uvs[v],
+                .color = quad.color,
+                .textureId = static_cast<std::uint32_t>(texId),
+            };
+        }
+
+        const std::uint32_t idxOffset = vertexBase / 4 * 6;
+        idxWrite[idxOffset + 0] = vertexBase + 0;
+        idxWrite[idxOffset + 1] = vertexBase + 1;
+        idxWrite[idxOffset + 2] = vertexBase + 2;
+        idxWrite[idxOffset + 3] = vertexBase + 0;
+        idxWrite[idxOffset + 4] = vertexBase + 2;
+        idxWrite[idxOffset + 5] = vertexBase + 3;
+        vertexBase += VerticesPerQuad;
+    }
+
+    auto& memMgr = gfxDevice.getMemoryManager();
+    memMgr.flushAllocation(vertexBuffer, 0, numVertices * sizeof(QuadVertex));
+    memMgr.flushAllocation(indexBuffer, 0, numIndices * sizeof(std::uint32_t));
+
+    auto renderInfo = vkutil::createRenderingInfo({
+        .renderExtent = target.getExtent2D(),
+        .colorImageView = target.imageView,
+    });
+
+    vkCmdBeginRendering(cmd, &renderInfo.renderingInfo);
+
+    pipeline->bind(cmd);
+    resources.bindBindlessDescSet(cmd, pipelineLayout);
+
+    const auto viewport = VkViewport{
+        .x = 0.0f,
+        .y = 0.0f,
+        .width = static_cast<float>(target.extent.width),
+        .height = static_cast<float>(target.extent.height),
+        .minDepth = 0.0f,
+        .maxDepth = 1.0f,
+    };
+    vkCmdSetViewport(cmd, 0, 1, &viewport);
+
+    const auto scissor = VkRect2D{
+        .offset = {},
+        .extent = target.getExtent2D(),
+    };
+    vkCmdSetScissor(cmd, 0, 1, &scissor);
+    vkCmdSetPolygonModeEXT(cmd, VK_POLYGON_MODE_FILL);
+
+    vkCmdPushConstants(
+        cmd,
+        pipelineLayout,
+        VK_SHADER_STAGE_VERTEX_BIT,
+        0,
+        sizeof(glm::mat4),
+        &projection);
+
+    const VkBuffer vertexBufferHandle = vertexBuffer.buffer;
+    const VkDeviceSize vertexBufferOffset = 0;
+    vkCmdBindVertexBuffers(cmd, 0, 1, &vertexBufferHandle, &vertexBufferOffset);
+
+    const VkBuffer indexBufferHandle = indexBuffer.buffer;
+    vkCmdBindIndexBuffer(cmd, indexBufferHandle, 0, VK_INDEX_TYPE_UINT32);
+
+    vkCmdDrawIndexed(cmd, static_cast<std::uint32_t>(numIndices), 1, 0, 0, 0);
+
+    vkCmdEndRendering(cmd);
+    quadManager.ClearQuads();
+}
+
+void QuadRendererPass::cleanup(GfxDevice& gfxDevice)
+{
+    pipeline.reset();
+
+    if (pipelineLayout != VK_NULL_HANDLE && gfxDevice.getDevice() != VK_NULL_HANDLE) {
+        vkDestroyPipelineLayout(gfxDevice.getDevice(), pipelineLayout, nullptr);
+    }
+    pipelineLayout = VK_NULL_HANDLE;
+
+    if (vertexBuffer.buffer != VK_NULL_HANDLE) {
+        gfxDevice.destroyBuffer(vertexBuffer);
+    }
+    if (indexBuffer.buffer != VK_NULL_HANDLE) {
+        gfxDevice.destroyBuffer(indexBuffer);
+    }
+    quadCapacity = 0;
+}
+
+void QuadRendererPass::ensureCapacity(
+    GfxDevice& gfxDevice,
+    std::size_t requiredQuads)
+{
+    if (requiredQuads <= quadCapacity) {
+        return;
+    }
+
+    std::size_t newCapacity = std::max(quadCapacity, InitialQuadCapacity);
+    while (newCapacity < requiredQuads) {
+        if (newCapacity > std::numeric_limits<std::size_t>::max() / 2) {
+            newCapacity = requiredQuads;
+            break;
+        }
+        newCapacity *= 2;
+    }
+
+    gfxDevice.waitIdle();
+
+    if (vertexBuffer.buffer != VK_NULL_HANDLE) {
+        gfxDevice.destroyBuffer(vertexBuffer);
+    }
+    vertexBuffer = gfxDevice.createBuffer(
+        newCapacity * VerticesPerQuad * sizeof(QuadVertex),
+        VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+        VMA_MEMORY_USAGE_AUTO_PREFER_HOST);
+
+    if (indexBuffer.buffer != VK_NULL_HANDLE) {
+        gfxDevice.destroyBuffer(indexBuffer);
+    }
+    indexBuffer = gfxDevice.createBuffer(
+        newCapacity * IndicesPerQuad * sizeof(std::uint32_t),
+        VK_BUFFER_USAGE_INDEX_BUFFER_BIT,
+        VMA_MEMORY_USAGE_AUTO_PREFER_HOST);
+
+    quadCapacity = newCapacity;
+}

destrum/src/Graphics/Renderer.cpp

@@ -1,10 +1,14 @@
 #include <destrum/Graphics/Renderer.h>
 
+#include <destrum/Graphics/Managers/LineRenderingManager.h>
+#include <destrum/Graphics/Managers/QuadRenderingManager.h>
 #include <destrum/Graphics/Util.h>
 
 #include <algorithm>
 #include <numeric>
 
+#include <glm/gtc/matrix_transform.hpp>
+
 #include "volk.h"
 #include "destrum/Util/GameState.h"
 #include "spdlog/spdlog.h"
@@ -36,6 +40,12 @@ void GameRenderer::init(GfxDevice& gfxDevice, RenderResources& _resources, glm::
         skinningPipeline = std::make_unique<SkinningPipeline>();
         skinningPipeline->init(gfxDevice);
 
+        lineRenderingPass = std::make_unique<LineRenderingPass>();
+        lineRenderingPass->init(gfxDevice, drawImageFormat);
+
+        quadRendererPass = std::make_unique<QuadRendererPass>();
+        quadRendererPass->init(gfxDevice, _resources, drawImageFormat);
+
         GameState::GetInstance().SetRenderer(this);
         initialized = true;
     } catch (...) {
@@ -49,6 +59,7 @@ void GameRenderer::beginDrawing(GfxDevice& gfxDevice)
     flushMaterialUpdates(gfxDevice);
     meshDrawCommands.clear();
     skinningPipeline->beginDrawing(gfxDevice.getCurrentFrameIndex());
+    QuadRenderingManager::GetInstance().ClearQuads();
 }
 
 void GameRenderer::endDrawing()
@@ -194,9 +205,43 @@ void GameRenderer::draw(VkCommandBuffer cmd, GfxDevice& gfxDevice, const Camera&
 
         vkCmdEndRendering(cmd);
     }
+
+    {
+        TracyVkZone(gfxDevice.getTracyVkCtx(), cmd, "LineRenderingPass::draw");
+
+        lineRenderingPass->draw(
+            cmd,
+            gfxDevice,
+            drawImage,
+            camera,
+            LineRenderingManager::GetInstance());
+    }
+
+    {
+        TracyVkZone(gfxDevice.getTracyVkCtx(), cmd, "QuadRendererPass::draw");
+
+        quadRendererPass->draw(
+            cmd,
+            gfxDevice,
+            *resources,
+            drawImage,
+            glm::ortho(0.0f,
+                static_cast<float>(drawImage.extent.width),
+                static_cast<float>(drawImage.extent.height),
+                0.0f, -1.0f, 1.0f));
+    }
 // vkutil::cmdEndLabel(cmd);
 }
 
+void GameRenderer::drawQuads(
+    VkCommandBuffer cmd,
+    GfxDevice& gfxDevice,
+    const glm::mat4& projection)
+{
+    const auto& drawImage = resources->getImage(drawImageId);
+    quadRendererPass->draw(cmd, gfxDevice, *resources, drawImage, projection);
+}
+
 void GameRenderer::cleanup(GfxDevice& gfxDevice)
 {
     VkDevice device = gfxDevice.getDevice();
@@ -208,6 +253,12 @@ void GameRenderer::cleanup(GfxDevice& gfxDevice)
 if (skinningPipeline)
         skinningPipeline->cleanup(gfxDevice);
 
+    if (lineRenderingPass)
+        lineRenderingPass->cleanup(gfxDevice);
+
+    if (quadRendererPass)
+        quadRendererPass->cleanup(gfxDevice);
+
     if (skyboxPipeline)
         skyboxPipeline->cleanup(device);
 
@@ -228,6 +279,8 @@ void GameRenderer::cleanup(GfxDevice& gfxDevice)
     meshPipeline.reset();
     skyboxPipeline.reset();
     skinningPipeline.reset();
+    lineRenderingPass.reset();
+    quadRendererPass.reset();
     pendingMaterialUploads.clear();
     meshDrawCommands.clear();
     sortedMeshDrawCommands.clear();

destrum/src/Input/InputManager.cpp

@@ -46,11 +46,11 @@ void InputManager::BeginFrame() {
 
     m_textInput.clear();
 
-    // Update mouse delta based on last known position
-    m_mouseDX = m_mouseX - m_prevMouseX;
-    m_mouseDY = m_mouseY - m_prevMouseY;
-    m_prevMouseX = m_mouseX;
-    m_prevMouseY = m_mouseY;
+    // Relative mouse accumulators are filled during SDL event processing
+    // and consumed by game code each frame. Reset them here (before events
+    // are processed) so this frame accumulates fresh deltas.
+    m_mouseRelDX = 0;
+    m_mouseRelDY = 0;
 
     // Clear controller "edge" sets + snapshot axes
     for (auto& [id, pad]: m_pads) {
@@ -60,6 +60,12 @@ void InputManager::BeginFrame() {
     }
 }
 
+void InputManager::SetMouseCaptured(bool captured) {
+    if (captured == m_MouseCaptured) return;
+    m_MouseCaptured = captured;
+    SDL_SetRelativeMouseMode(captured ? SDL_TRUE : SDL_FALSE);
+}
+
 void InputManager::AddController(int deviceIndex) {
     if (!SDL_IsGameController(deviceIndex)) return;
 
@@ -134,6 +140,8 @@ bool InputManager::ProcessEvent(const SDL_Event& e) {
         case SDL_MOUSEMOTION: {
             m_mouseX = e.motion.x;
             m_mouseY = e.motion.y;
+            m_mouseRelDX += e.motion.xrel;
+            m_mouseRelDY += e.motion.yrel;
         }
         break;
 

destrum/src/Physics/JoltPhysicsWorld.cpp

@@ -26,9 +26,12 @@
 #include <cstdarg>
 #include <cstdio>
 #include <memory>
+#include <mutex>
 #include <stdexcept>
 #include <thread>
 #include <unordered_map>
+#include <unordered_set>
+#include <vector>
 
 #include <glm/gtx/norm.hpp>
 
@@ -276,6 +279,84 @@ namespace
             throw std::runtime_error("Cannot create Jolt body without a valid shape.");
         }
     }
+
+    class SensorContactListener final : public ContactListener
+    {
+    public:
+        using BodyPair = std::pair<BodyID, BodyID>;
+
+        struct PairHash {
+            std::size_t operator()(const BodyPair& p) const {
+                return std::hash<uint32_t>{}(
+                    p.first.GetIndexAndSequenceNumber() ^
+                    (p.second.GetIndexAndSequenceNumber() << 7));
+            }
+        };
+
+        struct PairData {
+            GameObject* objA{nullptr};
+            GameObject* objB{nullptr};
+            bool sensorA{false};
+            bool sensorB{false};
+        };
+
+        ValidateResult OnContactValidate(const Body&, const Body&, RVec3Arg,
+                                         const CollideShapeResult&) override
+        {
+            return ValidateResult::AcceptAllContactsForThisBodyPair;
+        }
+
+        void OnContactAdded(const Body& body1, const Body& body2,
+                            const ContactManifold&, ContactSettings& ioSettings) override
+        {
+            if (body1.IsSensor() || body2.IsSensor())
+            {
+                PairData data;
+                data.objA = reinterpret_cast<GameObject*>(body1.GetUserData());
+                data.objB = reinterpret_cast<GameObject*>(body2.GetUserData());
+                data.sensorA = body1.IsSensor();
+                data.sensorB = body2.IsSensor();
+                std::lock_guard<std::mutex> lock(m_Mutex);
+                m_Overlaps.insert_or_assign(MakePair(body1.GetID(), body2.GetID()), data);
+            }
+        }
+
+        void OnContactPersisted(const Body& body1, const Body& body2,
+                                const ContactManifold&, ContactSettings&) override
+        {
+        }
+
+        void OnContactRemoved(const SubShapeIDPair& subShapePair) override
+        {
+            std::lock_guard<std::mutex> lock(m_Mutex);
+            m_Overlaps.erase(MakePair(subShapePair.GetBody1ID(), subShapePair.GetBody2ID()));
+        }
+
+        void Clear()
+        {
+            std::lock_guard<std::mutex> lock(m_Mutex);
+            m_Overlaps.clear();
+        }
+
+        std::unordered_map<BodyPair, PairData, PairHash> SwapOverlaps()
+        {
+            std::lock_guard<std::mutex> lock(m_Mutex);
+            return std::move(m_Overlaps);
+        }
+
+    private:
+        static BodyPair MakePair(BodyID a, BodyID b)
+        {
+            if (a.GetIndexAndSequenceNumber() < b.GetIndexAndSequenceNumber())
+            {
+                return {a, b};
+            }
+            return {b, a};
+        }
+
+        std::mutex m_Mutex;
+        std::unordered_map<BodyPair, PairData, PairHash> m_Overlaps;
+    };
 } // namespace
 
 class JoltPhysicsWorld::Impl
@@ -307,6 +388,7 @@ public:
             m_ObjectVsBroadPhaseLayerFilter,
             m_ObjectLayerPairFilter);
 
+        m_PhysicsSystem.SetContactListener(&m_SensorListener);
         m_PhysicsSystem.SetGravity(ToJoltVec3(settings.gravity));
     }
 
@@ -426,6 +508,15 @@ public:
             collisionSteps,
             m_TempAllocator.get(),
             m_JobSystem.get());
+
+        ProcessSensorOverlaps();
+    }
+
+    std::vector<TriggerEvent> ConsumeTriggerEvents()
+    {
+        std::vector<TriggerEvent> events;
+        m_TriggerEvents.swap(events);
+        return events;
     }
 
     void SyncKinematicBodiesToPhysics()
@@ -626,6 +717,43 @@ private:
         return {};
     }
 
+    void ProcessSensorOverlaps()
+    {
+        const auto currentOverlaps = m_SensorListener.SwapOverlaps();
+
+        for (const auto& [pair, data] : currentOverlaps)
+        {
+            if (m_PreviousSensorOverlaps.find(pair) == m_PreviousSensorOverlaps.end())
+            {
+                if (data.sensorA && data.objA)
+                {
+                    m_TriggerEvents.push_back({data.objA, data.objB, true});
+                }
+                if (data.sensorB && data.objB)
+                {
+                    m_TriggerEvents.push_back({data.objB, data.objA, true});
+                }
+            }
+        }
+
+        for (const auto& [pair, data] : m_PreviousSensorOverlaps)
+        {
+            if (currentOverlaps.find(pair) == currentOverlaps.end())
+            {
+                if (data.sensorA && data.objA)
+                {
+                    m_TriggerEvents.push_back({data.objA, data.objB, false});
+                }
+                if (data.sensorB && data.objB)
+                {
+                    m_TriggerEvents.push_back({data.objB, data.objA, false});
+                }
+            }
+        }
+
+        m_PreviousSensorOverlaps = std::move(currentOverlaps);
+    }
+
     Settings m_Settings{};
 
     BPLayerInterfaceImpl m_BPLayerInterface{};
@@ -639,6 +767,10 @@ private:
 
     std::unordered_map<std::uint32_t, BodyRecord> m_Bodies;
     std::uint32_t m_NextHandle{0};
+
+    SensorContactListener m_SensorListener;
+    std::unordered_map<SensorContactListener::BodyPair, SensorContactListener::PairData, SensorContactListener::PairHash> m_PreviousSensorOverlaps;
+    std::vector<TriggerEvent> m_TriggerEvents;
 };
 
 JoltPhysicsWorld::JoltPhysicsWorld(const Settings& settings)
@@ -710,3 +842,8 @@ bool JoltPhysicsWorld::Raycast(const glm::vec3& origin,
 {
     return m_Impl->Raycast(origin, direction, maxDistance, hit);
 }
+
+std::vector<TriggerEvent> JoltPhysicsWorld::ConsumeTriggerEvents()
+{
+    return m_Impl->ConsumeTriggerEvents();
+}

destrum/src/Physics/PhysicsSceneBridge.cpp

@@ -1,6 +1,7 @@
 #include <destrum/Physics/PhysicsSceneBridge.h>
 
 #include <destrum/Components/Physics/Rigidbody.h>
+#include <destrum/ObjectModel/Component.h>
 #include <destrum/ObjectModel/GameObject.h>
 
 PhysicsSceneBridge::PhysicsSceneBridge(std::unique_ptr<PhysicsWorld> world)
@@ -8,14 +9,16 @@ PhysicsSceneBridge::PhysicsSceneBridge(std::unique_ptr<PhysicsWorld> world)
 }
 
 void PhysicsSceneBridge::RegisterGameObject(GameObject& object) {
+    if (!m_World) return;
     if (auto* rb = object.GetComponent<Rigidbody>()) {
-        if (!rb->HasPhysicsBody() || rb->GetPhysicsWorld() != &GetWorld()) {
+        if (!rb->HasPhysicsBody() || rb->GetPhysicsWorld() != m_World.get()) {
             m_World->RegisterRigidbody(*rb);
         }
     }
 }
 
 void PhysicsSceneBridge::UnregisterGameObject(GameObject& object) {
+    if (!m_World) return;
     if (auto* rb = object.GetComponent<Rigidbody>()) {
         if (rb->GetPhysicsWorld() == m_World.get()) {
             m_World->UnregisterRigidbody(*rb);
@@ -24,13 +27,29 @@ void PhysicsSceneBridge::UnregisterGameObject(GameObject& object) {
 }
 
 void PhysicsSceneBridge::RefreshGameObject(GameObject& object) {
+    if (!m_World) return;
     if (auto* rb = object.GetComponent<Rigidbody>()) {
         m_World->RefreshRigidbody(*rb);
     }
 }
 
 void PhysicsSceneBridge::FixedUpdate(float fixedDt) {
+    if (!m_World) return;
     m_World->SyncKinematicBodiesToPhysics();
     m_World->Step(fixedDt);
+
+    for (const auto& event : m_World->ConsumeTriggerEvents()) {
+        if (event.owner == nullptr) continue;
+        for (const auto& component : event.owner->GetComponents()) {
+            if (component && !component->IsBeingDestroyed() && component->isEnabled()) {
+                if (event.entered) {
+                    component->OnTriggerEnter(event.other);
+                } else {
+                    component->OnTriggerExit(event.other);
+                }
+            }
+        }
+    }
+
     m_World->SyncDynamicBodiesToTransforms();
 }

destrum/src/Scene/Scene.cpp

@@ -23,7 +23,12 @@ namespace {
 }
 
 Scene::Scene(const std::string& name)
-    : m_name(name),
+    : Scene(name, std::make_unique<JoltPhysicsWorld>()) {
+}
+
+Scene::Scene(const std::string& name, std::unique_ptr<PhysicsWorld> physicsWorld)
+    : m_Physics(std::move(physicsWorld)),
+      m_name(name),
       m_id(++m_idCounter) {
 }
 

destrum/src/Scene/SceneManager.cpp

@@ -8,51 +8,41 @@
 #include <destrum/Util/DeltaTime.h>
 
 Scene& SceneManager::GetCurrentScene() const {
-    if (m_scenes.empty()) {
-        throw std::out_of_range("No scenes are available");
+    if (m_activeScenes.empty()) {
+        throw std::out_of_range("No active scenes are available");
     }
-
-    if (m_ActiveSceneIndex < 0 || m_ActiveSceneIndex >= static_cast<int>(m_scenes.size())) {
-        throw std::out_of_range("Active scene index is invalid");
-    }
-
-    return *m_scenes[static_cast<std::size_t>(m_ActiveSceneIndex)];
+    return *m_activeScenes.front();
 }
 
 void SceneManager::Update(float dt) {
-    if (m_scenes.empty()) return;
-    (void)GetCurrentScene();
-    const auto scene = m_scenes.at(static_cast<std::size_t>(m_ActiveSceneIndex));
+    for (const auto& scene : m_activeScenes) {
         scene->Update(dt);
     }
+}
 
 void SceneManager::FixedUpdate(float dt) {
-    if (m_scenes.empty()) return;
-    (void)GetCurrentScene();
-    const auto scene = m_scenes.at(static_cast<std::size_t>(m_ActiveSceneIndex));
+    for (const auto& scene : m_activeScenes) {
         scene->FixedUpdate(dt);
     }
+}
 
 void SceneManager::LateUpdate(float dt) {
-    if (m_scenes.empty()) return;
-    (void)GetCurrentScene();
-    const auto scene = m_scenes.at(static_cast<std::size_t>(m_ActiveSceneIndex));
+    for (const auto& scene : m_activeScenes) {
         scene->LateUpdate(dt);
     }
+}
 
 void SceneManager::Render(const RenderContext& ctx) {
-    if (m_scenes.empty()) return;
-    (void)GetCurrentScene();
-    const auto scene = m_scenes.at(static_cast<std::size_t>(m_ActiveSceneIndex));
+    for (const auto& scene : m_activeScenes) {
         scene->Render(ctx);
     }
+}
 
 void SceneManager::RenderImgui() {
-    if (m_scenes.empty()) return;
-    (void)GetCurrentScene();
-    const auto scene = m_scenes.at(static_cast<std::size_t>(m_ActiveSceneIndex));
+    for (const auto& scene : m_activeScenes) {
         scene->RenderImgui();
     }
+}
 
 void SceneManager::HandleGameObjectDestroy() {
     for (const auto& scene : m_scenes) {
@@ -73,37 +63,22 @@ void SceneManager::UnloadAllScenes() {
 }
 
 void SceneManager::HandleSceneDestroy() {
-    const std::shared_ptr<Scene> activeScene =
-        m_ActiveSceneIndex >= 0 &&
-        m_ActiveSceneIndex < static_cast<int>(m_scenes.size())
-            ? m_scenes[static_cast<std::size_t>(m_ActiveSceneIndex)]
-            : nullptr;
-
     for (auto it = m_scenes.begin(); it != m_scenes.end();) {
         if ((*it)->IsBeingUnloaded()) {
+            const auto activeIt = std::find(m_activeScenes.begin(), m_activeScenes.end(), *it);
+            if (activeIt != m_activeScenes.end()) {
+                m_activeScenes.erase(activeIt);
+            }
             it = m_scenes.erase(it);
         } else {
             ++it;
         }
     }
 
-    if (m_scenes.empty()) {
-        m_ActiveSceneIndex = 0;
-        return;
-    }
-
-    if (activeScene != nullptr) {
-        const auto activeIt = std::find(m_scenes.begin(), m_scenes.end(), activeScene);
-        if (activeIt != m_scenes.end()) {
-            m_ActiveSceneIndex = static_cast<int>(std::distance(m_scenes.begin(), activeIt));
-            return;
-        }
-    }
-
-    m_ActiveSceneIndex = std::clamp(
-        m_ActiveSceneIndex,
-        0,
-        static_cast<int>(m_scenes.size()) - 1);
+    // Remove any stale active scenes that are no longer in the scene list.
+    std::erase_if(m_activeScenes, [this](const auto& scene) {
+        return std::find(m_scenes.begin(), m_scenes.end(), scene) == m_scenes.end();
+    });
 }
 
 void SceneManager::HandleScene() {
@@ -113,7 +88,6 @@ void SceneManager::HandleScene() {
 
 void SceneManager::Destroy() {
     if (m_scenes.empty()) {
-        m_ActiveSceneIndex = 0;
         return;
     }
 
@@ -124,25 +98,60 @@ void SceneManager::Destroy() {
 }
 
 void SceneManager::SwitchScene(int index) {
-    // InputManager::GetInstance().RemoveAllBindings();
-
     if (index < 0 || index >= static_cast<int>(m_scenes.size())) {
         throw std::out_of_range("Scene index out of range");
     }
-    if (index == m_ActiveSceneIndex) {
-        return;
+
+    for (const auto& scene : m_activeScenes) {
+        scene->UnloadBindings();
+    }
+    m_activeScenes.clear();
+    m_activeScenes.push_back(m_scenes[static_cast<std::size_t>(index)]);
+    m_activeScenes.back()->LoadBindings();
 }
 
-    m_scenes[static_cast<std::size_t>(m_ActiveSceneIndex)]->UnloadBindings();
-    m_ActiveSceneIndex = index;
-    m_scenes[static_cast<std::size_t>(m_ActiveSceneIndex)]->LoadBindings();
+void SceneManager::AddActiveScene(int index) {
+    if (index < 0 || index >= static_cast<int>(m_scenes.size())) {
+        throw std::out_of_range("Scene index out of range");
+    }
+
+    const auto& scene = m_scenes[static_cast<std::size_t>(index)];
+    if (std::find(m_activeScenes.begin(), m_activeScenes.end(), scene) == m_activeScenes.end()) {
+        scene->LoadBindings();
+        m_activeScenes.push_back(scene);
+    }
+}
+
+void SceneManager::RemoveActiveScene(int index) {
+    if (index < 0 || index >= static_cast<int>(m_scenes.size())) {
+        throw std::out_of_range("Scene index out of range");
+    }
+
+    const auto& scene = m_scenes[static_cast<std::size_t>(index)];
+    const auto it = std::find(m_activeScenes.begin(), m_activeScenes.end(), scene);
+    if (it != m_activeScenes.end()) {
+        (*it)->UnloadBindings();
+        m_activeScenes.erase(it);
+    }
+}
+
+int SceneManager::GetActiveSceneId() const {
+    if (m_scenes.empty() || m_activeScenes.empty()) {
+        return -1;
+    }
+
+    const auto it = std::find(m_scenes.begin(), m_scenes.end(), m_activeScenes.front());
+    if (it == m_scenes.end()) {
+        return -1;
+    }
+    return static_cast<int>(std::distance(m_scenes.begin(), it));
 }
 
 Scene& SceneManager::CreateScene(const std::string& name) {
     const auto scene = std::shared_ptr<Scene>(new Scene(name));
     m_scenes.push_back(scene);
     if (m_scenes.size() == 1) {
-        m_ActiveSceneIndex = 0;
+        m_activeScenes.push_back(scene);
     }
     return *scene;
 }

destrum/src/Serialization/SceneSerializer.cpp

@@ -16,8 +16,10 @@
 #include <destrum/ObjectModel/GameObject.h>
 #include <destrum/ObjectModel/ObjectId.h>
 #include <destrum/ObjectModel/Transform.h>
+#include <destrum/Assets/AssetReference.h>
 #include <destrum/Components/Physics/Collider.h>
 #include <destrum/Components/Physics/Rigidbody.h>
+#include <destrum/FS/AssetFS.h>
 #include <destrum/Serialization/ComponentFactory.h>
 #include <destrum/Serialization/ComponentRegistry.h>
 
@@ -201,6 +203,78 @@ namespace {
 
         return true;
     }
+
+    [[nodiscard]] bool AssetFileExists(const std::string& path) {
+        if (path.empty()) {
+            return true;
+        }
+
+        std::filesystem::path fullPath;
+        if (path.find("://") != std::string::npos) {
+            try {
+                fullPath = AssetFS::GetInstance().GetFullPath(path);
+            } catch (const std::exception&) {
+                return false;
+            }
+        } else {
+            fullPath = path;
+        }
+
+        return std::filesystem::exists(fullPath);
+    }
+
+    void ValidateAssetReferences(const json& root, const std::filesystem::path& scenePath) {
+        const auto report = [&](const std::string& objectName, const std::string& detail) {
+            std::cerr << "Scene asset warning (" << scenePath << "): " << objectName
+                      << " references \"" << detail << "\" which could not be found\n";
+        };
+
+        for (const auto& objectJson : root.at("objects")) {
+            const std::string objectName = objectJson.value("name", "GameObject");
+            if (!objectJson.contains("components")) {
+                continue;
+            }
+
+            for (const auto& componentJson : objectJson.at("components")) {
+                if (!componentJson.contains("data")) {
+                    continue;
+                }
+                const auto& data = componentJson.at("data");
+
+                // MeshRendererComponent: meshKey / materialKey are asset cache keys.
+                for (const char* key : {"meshKey", "materialKey"}) {
+                    if (data.contains(key) && data.at(key).is_string()) {
+                        const std::string cacheKey = data.at(key).get<std::string>();
+                        if (cacheKey.empty()) continue;
+                        const auto asset = AssetReference::fromCacheKey(cacheKey);
+                        if (asset && !AssetFileExists(asset->path)) {
+                            report(objectName, cacheKey);
+                        }
+                    }
+                }
+
+                // Generic: any nested object with a "path" field is an AssetReference.
+                std::function<void(const json&)> walk = [&](const json& node) {
+                    if (node.is_object()) {
+                        if (node.contains("path") && node.at("path").is_string()) {
+                            const std::string path = node.at("path").get<std::string>();
+                            if (!path.empty() && !AssetFileExists(path)) {
+                                report(objectName, path);
+                            }
+                        }
+                        for (auto it = node.begin(); it != node.end(); ++it) {
+                            walk(it.value());
+                        }
+                    } else if (node.is_array()) {
+                        for (const auto& element : node) {
+                            walk(element);
+                        }
+                    }
+                };
+                walk(data);
+            }
+        }
+    }
 }
 
 bool SceneSerializer::Save(Scene& scene, const std::filesystem::path& path) {
@@ -290,30 +364,45 @@ bool SceneSerializer::Save(Scene& scene, const std::filesystem::path& path) {
     return true;
 }
 
-bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
+SceneSerializer::LoadResult SceneSerializer::LoadSceneFile(const std::filesystem::path& path) {
+    LoadResult result;
+
+    std::ifstream file(path);
+    if (!file.is_open()) {
+        result.errorMessage = "Failed to open scene file for reading: " + path.string();
+        std::cerr << result.errorMessage << '\n';
+        return result;
+    }
+
+    try {
+        file >> result.root;
+        if (!ValidateSceneJson(result.root)) {
+            result.errorMessage = "Invalid scene data: " + path.string();
+            std::cerr << result.errorMessage << '\n';
+            return result;
+        }
+    } catch (const std::exception& exception) {
+        result.errorMessage = "Failed to parse scene file: " + std::string(exception.what());
+        std::cerr << result.errorMessage << '\n';
+        return result;
+    }
+
+    ValidateAssetReferences(result.root, path);
+    result.success = true;
+    return result;
+}
+
+bool SceneSerializer::ConstructScene(Scene& scene, LoadResult& result,
+                                     std::function<void(float)> progressCallback) {
     if (scene.IsIterating()) {
         std::cerr << "Cannot load a scene during an update or render phase: "
                   << scene.GetName() << '\n';
         return false;
     }
 
-    RegisterEngineComponents();
-
-    std::ifstream file(path);
-    if (!file.is_open()) {
-        std::cerr << "Failed to open scene file for reading: " << path << '\n';
-        return false;
-    }
-
-    json root;
-    try {
-        file >> root;
-        if (!ValidateSceneJson(root)) {
-            std::cerr << "Invalid scene data: " << path << '\n';
-            return false;
-        }
-    } catch (const std::exception& exception) {
-        std::cerr << "Failed to parse scene file: " << exception.what() << '\n';
+    if (!result.success) {
+        std::cerr << "Cannot construct scene from a failed load result: "
+                  << result.errorMessage << '\n';
         return false;
     }
 
@@ -322,9 +411,16 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
         return false;
     }
 
+    RegisterEngineComponents();
+    if (progressCallback) progressCallback(0.35f);
+
+    const json& root = result.root;
+
     // Build the replacement separately. The current scene is not touched
     // until all objects, transforms, and components have loaded successfully.
-    Scene stagingScene(scene.GetName());
+    // No physics world is created for the staging scene - physics bodies are
+    // registered directly in the live scene's world once loading succeeds.
+    Scene stagingScene(scene.GetName(), nullptr);
     std::unordered_map<ObjectId, GameObject*> idMap;
     std::vector<const json*> objectJsonList;
     std::vector<GameObject*> registeredObjects;
@@ -343,7 +439,16 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
             objectJsonList.push_back(&objectJson);
         }
 
-        stagingScene.CommitPendingAdditions();
+        if (progressCallback) progressCallback(0.4f);
+
+        // Move objects from pending to objects list without physics registration
+        // (staging scene has no physics world).
+        for (auto& pending : stagingScene.m_pendingAdditions) {
+            if (pending) {
+                stagingScene.m_objects.emplace_back(std::move(pending));
+            }
+        }
+        stagingScene.m_pendingAdditions.clear();
 
         for (const json* objectJson : objectJsonList) {
             const ObjectId id = objectJson->at("id").get<ObjectId>();
@@ -392,6 +497,8 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
             }
         }
 
+        if (progressCallback) progressCallback(0.5f);
+
         for (const json* objectJson : objectJsonList) {
             GameObject* object = idMap.at(objectJson->at("id").get<ObjectId>());
             if (!objectJson->contains("components")) {
@@ -412,6 +519,8 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
             }
         }
 
+        if (progressCallback) progressCallback(0.6f);
+
         for (const auto& objectPtr : stagingScene.GetObjects()) {
             if (!objectPtr) {
                 continue;
@@ -424,6 +533,8 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
             }
         }
 
+        if (progressCallback) progressCallback(0.7f);
+
         // Register the replacement bodies in the live physics world before
         // touching the current scene. If any body fails, the old scene and
         // its physics state can remain intact.
@@ -438,6 +549,8 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
                 registeredObjects.push_back(objectPtr.get());
             }
         }
+
+        if (progressCallback) progressCallback(0.8f);
     } catch (const std::exception& exception) {
         std::cerr << "Failed to load scene: " << exception.what() << '\n';
         for (GameObject* object : registeredObjects) {
@@ -449,6 +562,7 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
         return false;
     }
 
+    scene.UnloadBindings();
     scene.RemoveAll();
     scene.m_objects = std::move(stagingScene.m_objects);
     scene.m_pendingAdditions = std::move(stagingScene.m_pendingAdditions);
@@ -456,6 +570,8 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
         scene.m_name = root.at("name").get<std::string>();
     }
 
+    if (progressCallback) progressCallback(0.9f);
+
     for (const auto& object : scene.m_objects) {
         if (object) {
             object->SetScene(&scene);
@@ -467,5 +583,27 @@ bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path) {
         }
     }
 
+    if (progressCallback) progressCallback(1.0f);
     return true;
 }
+
+bool SceneSerializer::Load(Scene& scene, const std::filesystem::path& path,
+                           std::function<void(float)> progressCallback) {
+    if (progressCallback) progressCallback(0.0f);
+
+    auto result = LoadSceneFile(path);
+    if (!result.success) {
+        if (progressCallback) progressCallback(1.0f);
+        return false;
+    }
+
+    if (progressCallback) progressCallback(0.3f);
+    return ConstructScene(scene, result, std::move(progressCallback));
+}
+
+std::future<SceneSerializer::LoadResult> SceneSerializer::LoadSceneFileAsync(
+    const std::filesystem::path& path) {
+    return std::async(std::launch::async, [path]() {
+        return LoadSceneFile(path);
+    });
+}

lightkeeper/CMakeLists.txt

@@ -6,6 +6,11 @@ set(GAME_SRC
     src/main.cpp
 
     src/Lightkeeper.cpp
+
+    src/components/GameComponentRegistry.cpp
+    src/components/FirstPersonController.cpp
+    src/components/PrintComponent.cpp
+    src/components/TriggerLoggerComponent.cpp
 )
 
 add_executable(lightkeeper ${GAME_SRC})

lightkeeper/include/Lightkeeper.h

@@ -10,6 +10,7 @@
 #include "destrum/Graphics/Resources/Cubemap.h"
 #include "destrum/ObjectModel/GameObject.h"
 
+class FirstPersonController;
 class LightKeeper final : public App {
 public:
     LightKeeper();
@@ -21,19 +22,33 @@ public:
     void customFixedUpdate(float dt) override;
 
     void onWindowResize(int newWidth, int newHeight) override;
+
 private:
+    void drawDebugMenuBar();
+    void saveCurrentScene();
+    void loadScene();
+    void createEmptyScene();
+    void submitBoxColliderDebugLines();
+
     Camera camera{glm::vec3(0.f, 0.f, -5.f), glm::vec3(0, 1, 0)};
 
     MeshID sphereMesh;
     MaterialID sphereMaterial;
 
+    ImageID texID;
+
     std::unique_ptr<CubeMap> skyboxCubemap;
 
     GameObject* capybara = nullptr;
+    GameObject* m_Player = nullptr;
+    FirstPersonController* m_FPSController = nullptr;
 
     char scenePath[512]{"scenes/debug_scene.json"};
     char newSceneName[128]{"EmptyScene"};
     std::string sceneStatus;
+    bool renderBoxColliders{false};
+    bool renderQuads{true};
+    bool renderDebugLines{true};
 };
 
 #endif //LIGHTKEEPER_H

lightkeeper/include/components/FirstPersonController.h

@@ -0,0 +1,48 @@
+#ifndef LIGHTKEEPER_FIRSTPERSONCONTROLLER_H
+#define LIGHTKEEPER_FIRSTPERSONCONTROLLER_H
+
+#include <glm/glm.hpp>
+#include <destrum/Input/InputManager.h>
+#include <destrum/ObjectModel/Component.h>
+
+class Rigidbody;
+class CapsuleCollider;
+
+class FirstPersonController final : public Component {
+public:
+    explicit FirstPersonController(GameObject& parent);
+
+    std::string GetTypeName() const override { return "FirstPersonController"; }
+
+    void Start() override;
+    void Update(float dt) override;
+    void FixedUpdate(float fixedDt) override;
+    void ImGuiInspector() override;
+    nlohmann::json Serialize() const override;
+    void Deserialize(const nlohmann::json& data) override;
+
+    [[nodiscard]] float GetYaw() const { return m_Yaw; }
+    [[nodiscard]] float GetPitch() const { return m_Pitch; }
+    [[nodiscard]] float GetEyeHeight() const { return m_EyeHeight; }
+
+    void SetMovementSpeed(float speed) { m_MovementSpeed = speed; }
+    [[nodiscard]] float GetMovementSpeed() const { return m_MovementSpeed; }
+
+    void SetMouseSensitivity(float sens) { m_MouseSensitivity = sens; }
+    [[nodiscard]] float GetMouseSensitivity() const { return m_MouseSensitivity; }
+
+    [[nodiscard]] bool IsMouseCaptured() const { return InputManager::GetInstance().IsMouseCaptured(); }
+    void SetMouseCaptured(bool captured);
+
+private:
+    Rigidbody* m_Rigidbody{nullptr};
+    CapsuleCollider* m_Capsule{nullptr};
+
+    float m_Yaw{0.0f};
+    float m_Pitch{0.0f};
+    float m_MovementSpeed{5.0f};
+    float m_MouseSensitivity{0.002f};
+    float m_EyeHeight{1.6f};
+};
+
+#endif

lightkeeper/include/components/GameComponentList.h

@@ -0,0 +1,13 @@
+#ifndef LIGHTKEEPER_GAMECOMPONENTLIST_H
+#define LIGHTKEEPER_GAMECOMPONENTLIST_H
+
+#include <components/FirstPersonController.h>
+#include <components/PrintComponent.h>
+#include <components/TriggerLoggerComponent.h>
+
+#define LIGHTKEEPER_GAME_COMPONENTS(X) \
+    X(FirstPersonController) \
+    X(PrintComponent) \
+    X(TriggerLoggerComponent)
+
+#endif // LIGHTKEEPER_GAMECOMPONENTLIST_H

lightkeeper/include/components/GameComponentRegistry.h

@@ -0,0 +1,6 @@
+#ifndef LIGHTKEEPER_GAMECOMPONENTREGISTRY_H
+#define LIGHTKEEPER_GAMECOMPONENTREGISTRY_H
+
+void RegisterGameComponents();
+
+#endif // LIGHTKEEPER_GAMECOMPONENTREGISTRY_H

lightkeeper/include/components/PrintComponent.h

@@ -0,0 +1,28 @@
+#ifndef DESTRUM_PRINTCOMPONENT_H
+#define DESTRUM_PRINTCOMPONENT_H
+#include "destrum/ObjectModel/Component.h"
+
+class PrintComponent: public Component {
+public:
+
+    PrintComponent(GameObject& parent);
+
+    std::string GetTypeName() const override { return "PrintComponent"; }
+    void Start() override;
+    void Update(float dt) override;
+    void ImGuiInspector() override;
+    nlohmann::json Serialize() const override;
+    void Deserialize(const nlohmann::json&) override;
+
+    void SetMessage(std::string_view message)
+    {
+        m_message = message;
+    }
+
+private:
+
+    std::string m_message{};
+
+};
+
+#endif //DESTRUM_PRINTCOMPONENT_H

lightkeeper/include/components/TriggerLoggerComponent.h

@@ -0,0 +1,22 @@
+#ifndef DESTRUM_TRIGGERLOGGERCOMPONENT_H
+#define DESTRUM_TRIGGERLOGGERCOMPONENT_H
+#include "destrum/ObjectModel/Component.h"
+
+class TriggerLoggerComponent: public Component {
+public:
+    TriggerLoggerComponent(GameObject& parent);
+
+    std::string GetTypeName() const override { return "TriggerLoggerComponent"; }
+
+    void OnTriggerEnter(GameObject* other) override;
+    void OnTriggerExit(GameObject* other) override;
+
+    nlohmann::json Serialize() const override;
+    void Deserialize(const nlohmann::json&) override;
+
+    int triggerEnterCount{0};
+    int triggerExitCount{0};
+    std::string lastOtherName;
+};
+
+#endif //DESTRUM_TRIGGERLOGGERCOMPONENT_H

lightkeeper/src/Lightkeeper.cpp

@@ -1,7 +1,11 @@
 #include "Lightkeeper.h"
 
+#include <array>
+#include <cmath>
 #include <destrum/FS/AssetFS.h>
 #include <destrum/Assets/AssetManager.h>
+#include <destrum/Graphics/Managers/LineRenderingManager.h>
+#include <destrum/Graphics/Managers/QuadRenderingManager.h>
 #include "glm/gtx/transform.hpp"
 #include "spdlog/spdlog.h"
 #include <destrum/Components/Physics/Rigidbody.h>
@@ -16,6 +20,8 @@
 #include "destrum/ObjectModel/GameObject.h"
 #include "destrum/Util/ModelDoc.h"
 #include "destrum/Components/Animator.h"
+#include <components/FirstPersonController.h>
+#include <components/TriggerLoggerComponent.h>
 
 
 #include <filesystem>
@@ -24,6 +30,8 @@
 #include <string_view>
 
 #include "imgui.h"
+#include "components/GameComponentRegistry.h"
+#include "components/PrintComponent.h"
 #include "destrum/Components/Physics/SphereCollider.h"
 #include "destrum/Util/ModelDocUtils.h"
 
@@ -60,6 +68,8 @@ LightKeeper::~LightKeeper()
 
 void LightKeeper::customInit()
 {
+    RegisterGameComponents();
+
     resources.init(gfxDevice);
     renderer.init(gfxDevice, resources, m_params.renderSize);
 
@@ -426,21 +436,61 @@ void LightKeeper::customInit()
 
     sphereMaterial = resources.materials().addSimpleColorMaterial({0.5f, 0.3f, 0.8f}, "Blue");
 
+
+    // Trigger zone: a static box with a TriggerLoggerComponent.
+    // Spheres spawned via the "Spawn ball" button fall through it.
+    auto triggerObj = scene.CreateGameObject("TriggerBox");
+    auto triggerBox = triggerObj->AddComponent<BoxCollider>(glm::vec3{3.0f, 3.0f, 3.0f});
+    triggerBox->SetTrigger(true);
+    auto triggerRb = triggerObj->AddComponent<Rigidbody>();
+    triggerRb->SetType(RigidbodyType::Static);
+    triggerObj->AddComponent<TriggerLoggerComponent>();
+    triggerObj->GetTransform().SetWorldPosition({0.0f, 0.0f, 0.0f});
+
+    auto playerObj = scene.CreateGameObject("Player");
+    playerObj->GetTransform().SetWorldPosition(glm::vec3(0.0f, 2.0f, -5.0f));
+    auto* fps = playerObj->AddComponent<FirstPersonController>();
+    m_Player = playerObj;
+    m_FPSController = fps;
+    scene.GetPhysics().RegisterGameObject(*playerObj);
+
+    const auto texPath = AssetFS::GetInstance().GetFullPath("engine://textures/kobe.png");
+    texID = resources.loadImageFromFile(gfxDevice, texPath);
+
 }
 
 void LightKeeper::customUpdate(float dt)
 {
     // LightKeeper owns a camera that hides App::camera; update this instance
     // after SDL events have been consumed.
+    if (m_FPSController != nullptr && m_FPSController->IsMouseCaptured())
+    {
+        auto& playerTransform = m_Player->GetTransform();
+        const glm::vec3 playerPos = playerTransform.GetWorldPosition();
+        camera.SetRotation(m_FPSController->GetYaw(), m_FPSController->GetPitch());
+        camera.m_position = playerPos + glm::vec3(0.0f, m_FPSController->GetEyeHeight(), 0.0f);
+        camera.CalculateViewMatrix();
+        camera.CalculateProjectionMatrix();
+    }
+    else
+    {
         camera.Update(dt);
+    }
     SceneManager::GetInstance().Update(dt);
     SceneManager::GetInstance().LateUpdate(dt);
 
+    if (m_params.showDebugUi) {
+        drawDebugMenuBar();
+    }
+
+    LineRenderingManager::GetInstance().SubmitLine({0, 0, 0}, {0, 10, 0}, {255, 0, 0, 255});
+
     if (InputManager::GetInstance().WasKeyPressed(SDL_SCANCODE_1))
     {
         renderer.setRenderWireframe(!renderer.getRenderWireframe());
     }
 
+    if (m_params.showDebugUi) {
         ImGui::Begin("Test");
         if (ImGui::Button("SPawn ball"))
         {
@@ -460,12 +510,57 @@ void LightKeeper::customUpdate(float dt)
             SceneManager::GetInstance().GetCurrentScene().GetPhysics().RefreshGameObject(*sphere);
         }
         ImGui::End();
+    }
 
-    ImGui::Begin("Scene Debug");
+}
+
+void LightKeeper::drawDebugMenuBar()
+{
+    if (!ImGui::BeginMainMenuBar()) {
+        return;
+    }
+
+    if (ImGui::BeginMenu("File")) {
+        ImGui::TextDisabled("Scene");
+
+        ImGui::SetNextItemWidth(320.0f);
         ImGui::InputText("Scene path", scenePath, sizeof(scenePath));
+
+        ImGui::SetNextItemWidth(320.0f);
         ImGui::InputText("New scene name", newSceneName, sizeof(newSceneName));
 
-    if (ImGui::Button("Save Current Scene")) {
+        ImGui::Separator();
+
+        if (ImGui::MenuItem("New Empty Scene")) {
+            createEmptyScene();
+        }
+        if (ImGui::MenuItem("Load")) {
+            loadScene();
+        }
+        if (ImGui::MenuItem("Save")) {
+            saveCurrentScene();
+        }
+
+        if (!sceneStatus.empty()) {
+            ImGui::Separator();
+            ImGui::TextWrapped("%s", sceneStatus.c_str());
+        }
+
+        ImGui::EndMenu();
+    }
+
+    if (ImGui::BeginMenu("Render")) {
+        ImGui::MenuItem("Box Colliders", nullptr, &renderBoxColliders);
+        ImGui::MenuItem("2D Quads", nullptr, &renderQuads);
+        ImGui::MenuItem("Debug Lines", nullptr, &renderDebugLines);
+        ImGui::EndMenu();
+    }
+
+    ImGui::EndMainMenuBar();
+}
+
+void LightKeeper::saveCurrentScene()
+{
     try {
         const auto path = ResolveScenePath(scenePath, m_params.exeDir);
         const auto parent = path.parent_path();
@@ -485,8 +580,8 @@ void LightKeeper::customUpdate(float dt)
     }
 }
 
-    ImGui::SameLine();
-    if (ImGui::Button("Load Scene")) {
+void LightKeeper::loadScene()
+{
     try {
         const auto path = ResolveScenePath(scenePath, m_params.exeDir);
         if (SceneSerializer::Load(
@@ -501,7 +596,8 @@ void LightKeeper::customUpdate(float dt)
     }
 }
 
-    if (ImGui::Button("New Empty Scene")) {
+void LightKeeper::createEmptyScene()
+{
     try {
         const std::string name = newSceneName[0] != '\0'
             ? newSceneName
@@ -516,10 +612,69 @@ void LightKeeper::customUpdate(float dt)
     }
 }
 
-    if (!sceneStatus.empty()) {
-        ImGui::TextWrapped("%s", sceneStatus.c_str());
+void LightKeeper::submitBoxColliderDebugLines()
+{
+    if (!renderBoxColliders) {
+        return;
+    }
+
+    auto& sceneManager = SceneManager::GetInstance();
+    if (sceneManager.GetSceneCount() == 0) {
+        return;
+    }
+
+    Scene& scene = sceneManager.GetCurrentScene();
+    auto& lineManager = LineRenderingManager::GetInstance();
+    constexpr std::array<std::array<std::size_t, 2>, 12> edges{{
+        {{0, 1}}, {{1, 3}}, {{3, 2}}, {{2, 0}},
+        {{4, 5}}, {{5, 7}}, {{7, 6}}, {{6, 4}},
+        {{0, 4}}, {{1, 5}}, {{2, 6}}, {{3, 7}},
+    }};
+
+    for (const auto& objectPtr : scene.GetObjects()) {
+        if (!objectPtr || objectPtr->IsBeingDestroyed() ||
+            !objectPtr->IsActiveInHierarchy()) {
+            continue;
+        }
+
+        const auto* boxCollider = objectPtr->GetComponent<BoxCollider>();
+        if (boxCollider == nullptr) {
+            continue;
+        }
+
+        // Collider dimensions are already in world units. Physics does not
+        // apply the GameObject scale when constructing the shape.
+        const glm::vec3 center = boxCollider->GetCenterOffset();
+        const glm::vec3 halfExtents = boxCollider->GetHalfExtents();
+        const std::array<glm::vec3, 8> localCorners{
+            center + glm::vec3{-halfExtents.x, -halfExtents.y, -halfExtents.z},
+            center + glm::vec3{ halfExtents.x, -halfExtents.y, -halfExtents.z},
+            center + glm::vec3{-halfExtents.x,  halfExtents.y, -halfExtents.z},
+            center + glm::vec3{ halfExtents.x,  halfExtents.y, -halfExtents.z},
+            center + glm::vec3{-halfExtents.x, -halfExtents.y,  halfExtents.z},
+            center + glm::vec3{ halfExtents.x, -halfExtents.y,  halfExtents.z},
+            center + glm::vec3{-halfExtents.x,  halfExtents.y,  halfExtents.z},
+            center + glm::vec3{ halfExtents.x,  halfExtents.y,  halfExtents.z},
+        };
+
+        Transform& transform = objectPtr->GetTransform();
+        const glm::vec3 worldPosition = transform.GetWorldPosition();
+        const glm::quat worldRotation = transform.GetWorldRotation();
+        std::array<glm::vec3, 8> worldCorners{};
+        for (std::size_t index = 0; index < localCorners.size(); ++index) {
+            worldCorners[index] = worldPosition + worldRotation * localCorners[index];
+        }
+
+        const glm::vec4 color = boxCollider->IsTrigger()
+            ? glm::vec4{1.0f, 0.75f, 0.1f, 1.0f}
+            : glm::vec4{0.1f, 0.8f, 1.0f, 1.0f};
+        for (const auto& edge : edges) {
+            lineManager.SubmitLine(
+                worldCorners[edge[0]],
+                worldCorners[edge[1]],
+                color);
+        }
     }
-    ImGui::End();
 }
 
 void LightKeeper::customDraw()
@@ -530,6 +685,11 @@ void LightKeeper::customDraw()
     }
 
     renderer.beginDrawing(gfxDevice);
+    submitBoxColliderDebugLines();
+
+    QuadRenderingManager::GetInstance().SubmitQuad(
+    glm::vec2{100.0f, 100.0f}, glm::vec2{200.0f, 200.0f}, 0.0f,
+    glm::vec4{1.0f}, texID);
 
     const RenderContext ctx{
         .renderer = renderer,

lightkeeper/src/components/FirstPersonController.cpp

@@ -0,0 +1,140 @@
+#include <components/FirstPersonController.h>
+
+#include <glm/glm.hpp>
+#include <glm/gtc/quaternion.hpp>
+#include <glm/gtx/norm.hpp>
+
+#include <destrum/Components/Physics/CapsuleCollider.h>
+#include <destrum/Components/Physics/Rigidbody.h>
+#include <destrum/Input/InputManager.h>
+#include <destrum/ObjectModel/GameObject.h>
+#include <destrum/Physics/PhysicsWorld.h>
+#include <destrum/Scene/Scene.h>
+
+#include <imgui.h>
+
+FirstPersonController::FirstPersonController(GameObject& parent)
+    : Component(parent, "FirstPersonController")
+{
+}
+
+void FirstPersonController::SetMouseCaptured(bool captured)
+{
+    InputManager::GetInstance().SetMouseCaptured(captured);
+}
+
+void FirstPersonController::Start()
+{
+    auto* obj = GetGameObject();
+    m_Capsule = obj->AddComponent<CapsuleCollider>(0.5f, 2.0f);
+    m_Rigidbody = obj->AddComponent<Rigidbody>();
+    m_Rigidbody->SetMass(80.0f);
+    m_Rigidbody->SetAllowSleep(false);
+    m_Rigidbody->SetUseGravity(true);
+}
+
+void FirstPersonController::Update(float)
+{
+    const auto& input = InputManager::GetInstance();
+
+    if (input.WasKeyPressed(SDL_SCANCODE_F5))
+    {
+        SetMouseCaptured(!IsMouseCaptured());
+    }
+
+    if (!IsMouseCaptured())
+    {
+        if (input.WasMousePressed(SDL_BUTTON_LEFT) && !ImGui::GetIO().WantCaptureMouse)
+        {
+            SetMouseCaptured(true);
+        }
+        return;
+    }
+
+    if (input.WasKeyPressed(SDL_SCANCODE_ESCAPE))
+    {
+        SetMouseCaptured(false);
+        return;
+    }
+
+    if (input.WasKeyPressed(SDL_SCANCODE_SPACE) && m_Rigidbody->HasPhysicsBody())
+    {
+        m_Rigidbody->AddImpulse(glm::vec3(0.0f, 400.0f, 0.0f));
+    }
+
+    m_Yaw += static_cast<float>(input.MouseDeltaX()) * m_MouseSensitivity;
+    m_Pitch -= static_cast<float>(input.MouseDeltaY()) * m_MouseSensitivity;
+    m_Pitch = glm::clamp(m_Pitch, glm::radians(-89.0f), glm::radians(89.0f));
+}
+
+void FirstPersonController::FixedUpdate(float)
+{
+    if (!IsMouseCaptured() || m_Rigidbody == nullptr || !m_Rigidbody->HasPhysicsBody())
+        return;
+
+    const auto& input = InputManager::GetInstance();
+
+    const float cosY = glm::cos(m_Yaw);
+    const float sinY = glm::sin(m_Yaw);
+    const glm::vec3 forward{cosY, 0.0f, sinY};
+    const glm::vec3 right{-sinY, 0.0f, cosY};
+
+    glm::vec3 moveDir(0.0f);
+    if (input.IsKeyDown(SDL_SCANCODE_W)) moveDir += forward;
+    if (input.IsKeyDown(SDL_SCANCODE_S)) moveDir -= forward;
+    if (input.IsKeyDown(SDL_SCANCODE_D)) moveDir += right;
+    if (input.IsKeyDown(SDL_SCANCODE_A)) moveDir -= right;
+
+    glm::vec3 velocity(0.0f);
+    if (glm::length2(moveDir) > 0.0f)
+    {
+        moveDir = glm::normalize(moveDir);
+        velocity = moveDir * m_MovementSpeed;
+    }
+
+    velocity.y = m_Rigidbody->GetLinearVelocity().y;
+    m_Rigidbody->SetLinearVelocity(velocity);
+
+    auto* world = m_Rigidbody->GetPhysicsWorld();
+    if (world != nullptr)
+    {
+        PhysicsTransform xform = world->GetBodyTransform(m_Rigidbody->GetBody());
+        xform.rotation = glm::quat(glm::vec3(0.0f, m_Yaw, 0.0f));
+        world->SetBodyTransform(m_Rigidbody->GetBody(), xform);
+    }
+}
+
+void FirstPersonController::ImGuiInspector()
+{
+    Component::ImGuiInspector();
+    ImGui::DragFloat("Movement Speed", &m_MovementSpeed, 0.1f, 0.0f, 100.0f);
+    ImGui::DragFloat("Mouse Sensitivity", &m_MouseSensitivity, 0.0001f, 0.0f, 0.1f);
+    ImGui::DragFloat("Eye Height", &m_EyeHeight, 0.01f, 0.0f, 5.0f);
+    ImGui::Text("Yaw: %.1f deg", glm::degrees(m_Yaw));
+    ImGui::Text("Pitch: %.1f deg", glm::degrees(m_Pitch));
+    bool captured = IsMouseCaptured();
+    ImGui::Checkbox("Mouse Captured", &captured);
+    if (captured != IsMouseCaptured()) {
+        SetMouseCaptured(captured);
+    }
+}
+
+nlohmann::json FirstPersonController::Serialize() const
+{
+    return {
+        {"movementSpeed", m_MovementSpeed},
+        {"mouseSensitivity", m_MouseSensitivity},
+        {"eyeHeight", m_EyeHeight},
+        {"yaw", m_Yaw},
+        {"pitch", m_Pitch},
+    };
+}
+
+void FirstPersonController::Deserialize(const nlohmann::json& data)
+{
+    if (data.contains("movementSpeed")) m_MovementSpeed = data.at("movementSpeed").get<float>();
+    if (data.contains("mouseSensitivity")) m_MouseSensitivity = data.at("mouseSensitivity").get<float>();
+    if (data.contains("eyeHeight")) m_EyeHeight = data.at("eyeHeight").get<float>();
+    if (data.contains("yaw")) m_Yaw = data.at("yaw").get<float>();
+    if (data.contains("pitch")) m_Pitch = data.at("pitch").get<float>();
+}

lightkeeper/src/components/GameComponentRegistry.cpp

@@ -0,0 +1,20 @@
+#include <components/GameComponentRegistry.h>
+
+#include <destrum/Serialization/ComponentFactory.h>
+
+#include <components/GameComponentList.h>
+
+void RegisterGameComponents()
+{
+    static bool registered = false;
+    if (registered) {
+        return;
+    }
+
+    registered = true;
+
+#define LIGHTKEEPER_REGISTER_COMPONENT(ComponentType) \
+    ComponentFactory::Register<ComponentType>(#ComponentType);
+    LIGHTKEEPER_GAME_COMPONENTS(LIGHTKEEPER_REGISTER_COMPONENT)
+#undef LIGHTKEEPER_REGISTER_COMPONENT
+}

lightkeeper/src/components/PrintComponent.cpp

@@ -0,0 +1,34 @@
+#include <components/PrintComponent.h>
+
+#include "spdlog/spdlog.h"
+
+PrintComponent::PrintComponent(GameObject& parent) : Component(parent, "PrintComponent")
+{
+}
+
+void PrintComponent::Start()
+{
+}
+
+void PrintComponent::Update(float dt)
+{
+    spdlog::debug(m_message);
+}
+
+void PrintComponent::ImGuiInspector()
+{
+    Component::ImGuiInspector();
+}
+
+nlohmann::json PrintComponent::Serialize() const
+{
+    return {"message", m_message};
+}
+
+void PrintComponent::Deserialize(const nlohmann::json& basic_jsons)
+{
+    if (basic_jsons.contains("message"))
+    {
+        m_message = basic_jsons.at("message").get<std::string>();
+    }
+}

lightkeeper/src/components/TriggerLoggerComponent.cpp

@@ -0,0 +1,45 @@
+#include <components/TriggerLoggerComponent.h>
+
+#include "spdlog/spdlog.h"
+#include <destrum/ObjectModel/GameObject.h>
+
+TriggerLoggerComponent::TriggerLoggerComponent(GameObject& parent)
+    : Component(parent, "TriggerLoggerComponent") {}
+
+void TriggerLoggerComponent::OnTriggerEnter(GameObject* other) {
+    ++triggerEnterCount;
+    lastOtherName = other ? other->GetName() : "null";
+    spdlog::info(
+        "TriggerLogger: ENTER {} -> {} (enters: {}, exits: {})",
+        GetGameObject()->GetName(),
+        lastOtherName,
+        triggerEnterCount,
+        triggerExitCount);
+}
+
+void TriggerLoggerComponent::OnTriggerExit(GameObject* other) {
+    ++triggerExitCount;
+    lastOtherName = other ? other->GetName() : "null";
+    spdlog::info(
+        "TriggerLogger: EXIT {} -> {} (enters: {}, exits: {})",
+        GetGameObject()->GetName(),
+        lastOtherName,
+        triggerEnterCount,
+        triggerExitCount);
+}
+
+nlohmann::json TriggerLoggerComponent::Serialize() const {
+    return {
+        {"triggerEnterCount", triggerEnterCount},
+        {"triggerExitCount", triggerExitCount}
+    };
+}
+
+void TriggerLoggerComponent::Deserialize(const nlohmann::json& data) {
+    if (data.contains("triggerEnterCount")) {
+        triggerEnterCount = data.at("triggerEnterCount").get<int>();
+    }
+    if (data.contains("triggerExitCount")) {
+        triggerExitCount = data.at("triggerExitCount").get<int>();
+    }
+}

tests/destrum_tests.cpp

@@ -20,9 +20,11 @@
 #include <destrum/Physics/JoltPhysicsWorld.h>
 #include <destrum/Components/Physics/SphereCollider.h>
 #include <destrum/Components/Physics/BoxCollider.h>
+#include <destrum/Components/Physics/Collider.h>
 #include <destrum/Components/Animator.h>
 #include <destrum/Components/Physics/Rigidbody.h>
 #include <destrum/Graphics/Material.h>
+#include <destrum/Graphics/Managers/LineRenderingManager.h>
 
 namespace {
     class TestComponent final : public Component {
@@ -189,6 +191,29 @@ namespace {
               "RigidBody legacy alias must not be registered");
     }
 
+    void testLineRenderingManager()
+    {
+        auto& lineManager = LineRenderingManager::GetInstance();
+        lineManager.ClearLines();
+
+        lineManager.SubmitLine(
+            glm::vec3{0.0f},
+            glm::vec3{1.0f, 0.0f, 0.0f},
+            glm::vec4{1.0f, 0.0f, 0.0f, 1.0f});
+        lineManager.SubmitLine(Line{
+            .start = glm::vec3{1.0f},
+            .end = glm::vec3{2.0f},
+            .color = glm::vec4{0.0f, 1.0f, 0.0f, 1.0f},
+        });
+
+        check(lineManager.GetLines().size() == 2,
+              "line rendering manager must retain submitted lines");
+
+        lineManager.ClearLines();
+        check(lineManager.GetLines().empty(),
+              "line rendering manager must clear transient lines");
+    }
+
     void testAssetPathValidation()
     {
         const auto root = std::filesystem::temp_directory_path() / "destrum_asset_test";
@@ -459,6 +484,65 @@ namespace {
         check(!AssetReference::fromCacheKey("CharacterMedium.fbx").has_value(),
               "plain cache names must not be treated as file-backed assets");
     }
+
+    class TriggerTracker final : public Component {
+    public:
+        explicit TriggerTracker(GameObject& owner)
+            : Component(owner, "TriggerTracker") {}
+
+        void Update(float) override {}
+        std::string GetTypeName() const override { return "TriggerTracker"; }
+
+        void OnTriggerEnter(GameObject* other) override {
+            ++enterCount;
+            lastOther = other;
+            enterObjectName = other ? other->GetName() : "null";
+        }
+
+        void OnTriggerExit(GameObject* other) override {
+            ++exitCount;
+        }
+
+        int enterCount{0};
+        int exitCount{0};
+        GameObject* lastOther{nullptr};
+        std::string enterObjectName;
+    };
+
+    void testTriggerZone()
+    {
+        Scene& scene = SceneManager::GetInstance().CreateScene("trigger-test");
+
+        // Trigger box at origin (Static rigidbody + BoxCollider as trigger).
+        GameObject* triggerObj = scene.CreateGameObject("TriggerZone");
+        triggerObj->AddComponent<BoxCollider>(glm::vec3{3.0f, 3.0f, 3.0f});
+        triggerObj->GetComponent<BoxCollider>()->SetTrigger(true);
+        auto* triggerRb = triggerObj->AddComponent<Rigidbody>();
+        triggerRb->SetType(RigidbodyType::Static);
+        auto* tracker = triggerObj->AddComponent<TriggerTracker>();
+
+        // Falling sphere above the trigger.
+        GameObject* sphere = scene.CreateGameObject("FallingSphere");
+        sphere->AddComponent<SphereCollider>(0.5f);
+        sphere->AddComponent<Rigidbody>();
+        sphere->GetTransform().SetWorldPosition({0.0f, 8.0f, 0.0f});
+
+        scene.CommitPendingAdditions();
+
+        // Run physics for enough steps that the sphere falls into the trigger.
+        for (int step = 0; step < 120; ++step) {
+            scene.FixedUpdate(1.0f / 60.0f);
+        }
+
+        check(tracker->enterCount >= 1,
+              "falling sphere must trigger OnTriggerEnter at least once");
+        check(tracker->exitCount >= 1,
+              "falling sphere passing through trigger must exit");
+        check(tracker->enterObjectName == "FallingSphere",
+              "OnTriggerEnter must report the correct entering object");
+
+        SceneManager::GetInstance().Destroy();
+    }
 }
 
 int main()
@@ -469,6 +553,7 @@ int main()
     testEventRemoval();
     testComponentRemoval();
     testEngineComponentRegistration();
+    testLineRenderingManager();
     testAssetPathValidation();
     testLegacySceneLoad();
     testSceneLoadRollback();
@@ -478,6 +563,7 @@ int main()
     testAnimatorAssetReferences();
     testSimpleColorMaterial();
     testAssetReferenceCacheKeys();
+    testTriggerZone();
     std::cout << "destrum tests passed\n";
     return EXIT_SUCCESS;
 }