ADD: SSR with RT

src/core/context.h

@@ -76,6 +76,9 @@ public:
     // Runtime settings visible to passes/shaders
     ShadowSettings shadowSettings{};
     bool enableSSR = false;                      // optional screen-space reflections toggle
+    // Reflection mode for SSR/RT reflections; encoded into sceneData.rtOptions.w
+    // 0 = SSR only, 1 = SSR + RT fallback, 2 = RT only
+    uint32_t reflectionMode = 0;
 
     // Ray tracing manager (optional, nullptr if unsupported)
     RayTracingManager* ray = nullptr;

src/core/engine.cpp

@@ -569,8 +569,12 @@ void VulkanEngine::draw()
     //now that we are sure that the commands finished executing, we can safely reset the command buffer to begin recording again.
     VK_CHECK(vkResetCommandBuffer(get_current_frame()._mainCommandBuffer, 0));
 
-    // Build or update TLAS for current frame now that the previous frame is idle
-    if (_rayManager && _context->shadowSettings.mode != 0u)
+    // Build or update TLAS for current frame now that the previous frame is idle.
+    // TLAS is used for hybrid/full RT shadows and RT-assisted SSR reflections.
+    // For reflections, only build TLAS when RT is actually enabled (reflectionMode != 0).
+    if (_rayManager &&
+        (_context->shadowSettings.mode != 0u ||
+         (_context->enableSSR && _context->reflectionMode != 0u)))
     {
         _rayManager->buildTLASFromDrawContext(_context->getMainDrawContext(), get_current_frame()._deletionQueue);
     }

src/core/engine_ui.cpp

@@ -602,6 +602,34 @@ namespace
     static void ui_postfx(VulkanEngine *eng)
     {
         if (!eng) return;
+        if (!eng->_context) return;
+
+        EngineContext *ctx = eng->_context.get();
+
+        ImGui::TextUnformatted("Reflections");
+        bool ssrEnabled = ctx->enableSSR;
+        if (ImGui::Checkbox("Enable Screen-Space Reflections", &ssrEnabled))
+        {
+            ctx->enableSSR = ssrEnabled;
+        }
+
+        int reflMode = static_cast<int>(ctx->reflectionMode);
+        ImGui::TextUnformatted("Reflection Mode");
+        ImGui::RadioButton("SSR only", &reflMode, 0);
+        ImGui::SameLine();
+        ImGui::RadioButton("SSR + RT fallback", &reflMode, 1);
+        ImGui::SameLine();
+        ImGui::RadioButton("RT only", &reflMode, 2);
+
+        const bool rq = eng->_deviceManager->supportsRayQuery();
+        const bool as = eng->_deviceManager->supportsAccelerationStructure();
+        if (!(rq && as) && reflMode != 0)
+        {
+            reflMode = 0; // guard for unsupported HW
+        }
+        ctx->reflectionMode = static_cast<uint32_t>(reflMode);
+
+        ImGui::Separator();
         if (auto *tm = eng->_renderPassManager ? eng->_renderPassManager->getPass<TonemapPass>() : nullptr)
         {
             float exp = tm->exposure();