[vulkan] Add support for target FPS frame pacing (#3494)

This allows users to choose how the emulator manages frame pacing to reduce stuttering and provide a smoother and more consistent frame rate.

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3494
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Co-authored-by: MaranBr <maranbr@outlook.com>
Co-committed-by: MaranBr <maranbr@outlook.com>

3 files changed, 68 insertions, 8 deletions

diff --git a/src/video_core/renderer_vulkan/vk_scheduler.cpp b/src/video_core/renderer_vulkan/vk_scheduler.cpp
index aafcfdf65b..2a69d6d244 100644
--- a/src/video_core/renderer_vulkan/vk_scheduler.cpp
+++ b/src/video_core/renderer_vulkan/vk_scheduler.cpp
@@ -347,7 +347,7 @@ void Scheduler::EndRenderPass()
         Record([num_images = num_renderpass_images,
                        images = renderpass_images,
                        ranges = renderpass_image_ranges](vk::CommandBuffer cmdbuf) {
-            std::array<VkImageMemoryBarrier, 9> barriers;
+            std::vector<VkImageMemoryBarrier> barriers(num_images);
             VkPipelineStageFlags src_stages = 0;
             for (size_t i = 0; i < num_images; ++i) {
                 const VkImageSubresourceRange& range = ranges[i];
diff --git a/src/video_core/renderer_vulkan/vk_scheduler.h b/src/video_core/renderer_vulkan/vk_scheduler.h
index 5216a436c8..fb0ac9b008 100644
--- a/src/video_core/renderer_vulkan/vk_scheduler.h
+++ b/src/video_core/renderer_vulkan/vk_scheduler.h
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: Copyright 2019 yuzu Emulator Project
@@ -16,6 +16,7 @@
 
 #include "common/alignment.h"
 #include "common/common_types.h"
+#include "common/settings.h"
 #include "common/polyfill_thread.h"
 #include "video_core/renderer_vulkan/vk_master_semaphore.h"
 #include "video_core/vulkan_common/vulkan_wrapper.h"
@@ -111,15 +112,34 @@ public:
         return master_semaphore->IsFree(tick);
     }
 
-    /// Waits for the given tick to trigger on the GPU.
-    void Wait(u64 tick) {
-        if (tick >= master_semaphore->CurrentTick()) {
-            // Make sure we are not waiting for the current tick without signalling
+    /// Waits for the given GPU tick, optionally pacing frames.
+    void Wait(u64 tick, double target_fps = 0.0) {
+        if (Settings::values.use_speed_limit.GetValue() && target_fps > 0.0) {
+            auto frame_duration = std::chrono::duration_cast<std::chrono::steady_clock::duration>(std::chrono::duration<double>(1.0 / target_fps));
+            auto now = std::chrono::steady_clock::now();
+            if (now < next_frame_time) {
+                std::this_thread::sleep_until(next_frame_time);
+                next_frame_time += frame_duration;
+            } else {
+                next_frame_time = now + frame_duration;
+            }
+        }
+        if (tick > master_semaphore->CurrentTick() && !chunk->Empty()) {
             Flush();
         }
         master_semaphore->Wait(tick);
     }
 
+    /// Resets the frame pacing state by setting the next frame time.
+    void ResetFramePacing(double target_fps = 0.0) {
+        if (target_fps > 0.0) {
+            auto frame_duration = std::chrono::duration_cast<std::chrono::steady_clock::duration>(std::chrono::duration<double>(1.0 / target_fps));
+            next_frame_time = std::chrono::steady_clock::now() + frame_duration;
+        } else {
+            next_frame_time = std::chrono::steady_clock::time_point{};
+        }
+    }
+
     /// Returns the master timeline semaphore.
     [[nodiscard]] MasterSemaphore& GetMasterSemaphore() const noexcept {
         return *master_semaphore;
@@ -261,6 +281,8 @@ private:
     std::mutex queue_mutex;
     std::condition_variable_any event_cv;
     std::jthread worker_thread;
+
+    std::chrono::steady_clock::time_point next_frame_time{};
 };
 
 } // namespace Vulkan
diff --git a/src/video_core/renderer_vulkan/vk_swapchain.cpp b/src/video_core/renderer_vulkan/vk_swapchain.cpp
index 7418ad934e..7e7e67639d 100644
--- a/src/video_core/renderer_vulkan/vk_swapchain.cpp
+++ b/src/video_core/renderer_vulkan/vk_swapchain.cpp
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: Copyright 2019 yuzu Emulator Project
@@ -146,6 +146,25 @@ void Swapchain::Create(
 {
     is_outdated = false;
     is_suboptimal = false;
+
+    switch (Settings::values.frame_pacing_mode.GetValue()) {
+    case Settings::FramePacingMode::Target_Auto:
+        scheduler.ResetFramePacing();
+        break;
+    case Settings::FramePacingMode::Target_30:
+        scheduler.ResetFramePacing(30.0);
+        break;
+    case Settings::FramePacingMode::Target_60:
+        scheduler.ResetFramePacing(60.0);
+        break;
+    case Settings::FramePacingMode::Target_120:
+        scheduler.ResetFramePacing(120.0);
+        break;
+    case Settings::FramePacingMode::Target_240:
+        scheduler.ResetFramePacing(240.0);
+        break;
+    }
+
     width = width_;
     height = height_;
 #ifdef ANDROID
@@ -194,7 +213,26 @@ bool Swapchain::AcquireNextImage() {
         break;
     }
 
-    scheduler.Wait(resource_ticks[image_index]);
+    if (resource_ticks[image_index] != 0 && !scheduler.IsFree(resource_ticks[image_index])) {
+        switch (Settings::values.frame_pacing_mode.GetValue()) {
+        case Settings::FramePacingMode::Target_Auto:
+            scheduler.Wait(resource_ticks[image_index]);
+            break;
+        case Settings::FramePacingMode::Target_30:
+            scheduler.Wait(resource_ticks[image_index], 30.0);
+            break;
+        case Settings::FramePacingMode::Target_60:
+            scheduler.Wait(resource_ticks[image_index], 60.0);
+            break;
+        case Settings::FramePacingMode::Target_120:
+            scheduler.Wait(resource_ticks[image_index], 120.0);
+            break;
+        case Settings::FramePacingMode::Target_240:
+            scheduler.Wait(resource_ticks[image_index], 240.0);
+            break;
+        }
+    }
+
     resource_ticks[image_index] = scheduler.CurrentTick();
 
     return is_suboptimal || is_outdated;