ADD: CSM with normal shadow

src/core/config.h

@@ -10,10 +10,10 @@ inline constexpr bool kUseValidationLayers = true;
 // Shadow mapping configuration
 inline constexpr int kShadowCascadeCount = 4;
 // Maximum shadow distance for CSM in view-space units
-inline constexpr float kShadowCSMFar = 200.0f;
+inline constexpr float kShadowCSMFar = 400.0f;
 // Shadow map resolution used for stabilization (texel snapping). Must match actual image size.
 inline constexpr float kShadowMapResolution = 2048.0f;
 // Extra XY expansion for cascade footprint (safety against FOV/aspect changes)
-inline constexpr float kShadowCascadeRadiusScale = 1.25f;
+inline constexpr float kShadowCascadeRadiusScale = 2.5f;
 // Additive XY margin in world units (light-space) beyond scaled radius
-inline constexpr float kShadowCascadeRadiusMargin = 20.0f;
+inline constexpr float kShadowCascadeRadiusMargin = 40.0f;

src/scene/vk_scene.cpp

@@ -124,10 +124,10 @@ void SceneManager::update_scene()
 
         // 0) Legacy near/simple shadow (cascade 0 그대로)
         {
-            const float orthoRange = 20.0f;
+            const float orthoRange = 10.0f;
             const float nearDist = 0.1f;
             const float farDist = 200.0f;
-            const glm::vec3 lightPos = camPos - L * 80.0f;
+            const glm::vec3 lightPos = camPos - L * 180.0f;
             const glm::mat4 viewLight = glm::lookAtRH(lightPos, camPos, up);
 
             // ⚠️ API에 맞게 ZO/NO를 고르세요 (Vulkan/D3D: ZO, OpenGL 기본: NO)
@@ -179,7 +179,7 @@ void SceneManager::update_scene()
             glm::vec3 center(0.0f);
             for (auto &p: ws) center += p;
             center *= (1.0f / 8.0f);
-            const float lightPullback = 30.0f; // 충분히 뒤로 빼서 안정화
+            const float lightPullback = 50.0f; // 충분히 뒤로 빼서 안정화
             glm::mat4 V = glm::lookAtRH(center - L * lightPullback, center, up);
 
             // 라이트 공간으로 투영 후 AABB