feat: add basic forward lighting coverage

engine/include/XCEngine/Rendering/Pipelines/BuiltinForwardPipeline.h

@@ -59,6 +59,9 @@ private:
         Math::Matrix4x4 projection = Math::Matrix4x4::Identity();
         Math::Matrix4x4 view = Math::Matrix4x4::Identity();
         Math::Matrix4x4 model = Math::Matrix4x4::Identity();
+        Math::Matrix4x4 normalMatrix = Math::Matrix4x4::Identity();
+        Math::Vector4 mainLightDirectionAndIntensity = Math::Vector4::Zero();
+        Math::Vector4 mainLightColorAndFlags = Math::Vector4::Zero();
     };
 
     bool EnsureInitialized(const RenderContext& context);

engine/include/XCEngine/Rendering/RenderSceneExtractor.h

@@ -16,9 +16,25 @@ class Scene;
 
 namespace Rendering {
 
+struct RenderDirectionalLightData {
+    bool enabled = false;
+    Math::Vector3 direction = Math::Vector3::Back();
+    float intensity = 1.0f;
+    Math::Color color = Math::Color::White();
+};
+
+struct RenderLightingData {
+    RenderDirectionalLightData mainDirectionalLight;
+
+    bool HasMainDirectionalLight() const {
+        return mainDirectionalLight.enabled;
+    }
+};
+
 struct RenderSceneData {
     Components::CameraComponent* camera = nullptr;
     RenderCameraData cameraData;
+    RenderLightingData lighting;
     std::vector<VisibleRenderItem> visibleItems;
 
     bool HasCamera() const { return camera != nullptr; }
@@ -45,6 +61,9 @@ private:
         const Components::CameraComponent& camera,
         uint32_t viewportWidth,
         uint32_t viewportHeight) const;
+    void ExtractLighting(
+        const Components::Scene& scene,
+        RenderLightingData& lightingData) const;
     void ExtractVisibleItems(
         Components::GameObject* gameObject,
         const Math::Vector3& cameraPosition,