From e0f7daf292db65d8aa492b6bc29ad245a9f83a2d Mon Sep 17 00:00:00 2001
From: Nicolas James <nj3ahxac@gmail.com>
Date: Sun, 15 Feb 2026 12:52:19 +1100
Subject: Implement anti lag 1 / whatever nvidia reflex equivalent is

---
 src/queue_context.hh | 36 +++++++++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 9 deletions(-)

(limited to 'src/queue_context.hh')

diff --git a/src/queue_context.hh b/src/queue_context.hh
index 3df6af4..6a71754 100644
--- a/src/queue_context.hh
+++ b/src/queue_context.hh
@@ -2,6 +2,7 @@
 #define QUEUE_STATE_HH_
 
 #include "context.hh"
+#include "device_context.hh"
 #include "timestamp_pool.hh"
 
 #include <vulkan/utility/vk_dispatch_table.h>
@@ -14,8 +15,6 @@
 
 namespace low_latency {
 
-class DeviceContext;
-
 class QueueContext final : public Context {
   public:
     DeviceContext& device_context;
@@ -23,6 +22,8 @@ class QueueContext final : public Context {
     const VkQueue queue;
     const std::uint32_t queue_family_index;
 
+    // I used to use these to signal when we could read timestamps until
+    // I realised you could use hostQueryReset.
     std::uint64_t semaphore_sequence = 0;
     VkSemaphore semaphore;
 
@@ -30,14 +31,17 @@ class QueueContext final : public Context {
 
     std::unique_ptr<TimestampPool> timestamp_pool;
 
+  private:
+    static constexpr auto MAX_TRACKED_TIMINGS = 50;
     // Potentially in flight queue submissions
     struct Submission {
         const std::unordered_set<VkSemaphore> signals;
         const std::unordered_set<VkSemaphore> waits;
-        const std::uint64_t sequence;
 
         const std::shared_ptr<TimestampPool::Handle> start_handle;
         const std::shared_ptr<TimestampPool::Handle> end_handle;
+
+        bool end_of_frame_marker = false;
     };
     std::deque<std::shared_ptr<Submission>> submissions;
 
@@ -48,7 +52,6 @@ class QueueContext final : public Context {
         struct Timepoint {
             const QueueContext& context;
             const std::shared_ptr<TimestampPool::Handle> handle;
-            const std::uint64_t sequence;
         };
 
         const Timepoint start;
@@ -56,6 +59,20 @@ class QueueContext final : public Context {
     };
     std::deque<std::unique_ptr<Frame>> in_flight_frames;
 
+    struct Timing {
+
+        DeviceContext::Clock::time_point_t gpu_start;
+        DeviceContext::Clock::time_point_t gpu_end;
+
+        // Distance between the last gpu_end and this one.
+        // So one entire go around, including all cpu and gpu.
+        DeviceContext::Clock::time_point_t::duration frametime;
+    };
+    std::deque<std::unique_ptr<Timing>> timings;
+
+  private:
+    void process_frames();
+
   public:
     QueueContext(DeviceContext& device_context, const VkQueue& queue,
                  const std::uint32_t& queue_family_index);
@@ -63,18 +80,19 @@ class QueueContext final : public Context {
 
   public:
     void
-    notify_submit(const VkSubmitInfo& info, const std::uint64_t& sequence,
+    notify_submit(const VkSubmitInfo& info,
                   const std::shared_ptr<TimestampPool::Handle> head_handle,
                   const std::shared_ptr<TimestampPool::Handle> tail_handle);
 
-    // TODO submit2
+    void
+    notify_submit(const VkSubmitInfo2& info,
+                  const std::shared_ptr<TimestampPool::Handle> head_handle,
+                  const std::shared_ptr<TimestampPool::Handle> tail_handle);
 
     void notify_present(const VkPresentInfoKHR& info);
 
   public:
-    // Computes the amount we should delay...
-    using duration_t = std::chrono::steady_clock::duration;
-    std::optional<duration_t> get_delay_time();
+    std::optional<DeviceContext::Clock::time_point_t> get_sleep_until();
 };
 
 }; // namespace low_latency
-- 
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