From 5674abe483b4350fe173317132438ea57a3b5bba Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Thu, 6 Jun 2024 10:44:20 +0200
Subject: [PATCH] [d3d9] Limit frame rate to display refresh as necessary

---
 src/d3d9/d3d9_swapchain.cpp | 13 ++++++++++++-
 src/d3d9/d3d9_swapchain.h   |  2 ++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/d3d9/d3d9_swapchain.cpp b/src/d3d9/d3d9_swapchain.cpp
index 577243306..1d1c7c382 100644
--- a/src/d3d9/d3d9_swapchain.cpp
+++ b/src/d3d9/d3d9_swapchain.cpp
@@ -191,6 +191,7 @@ namespace dxvk {
       if (!m_wctx->presenter->hasSwapChain())
         return D3D_OK;
 
+      UpdateTargetFrameRate(presentInterval);
       PresentImage(presentInterval);
       return D3D_OK;
     } catch (const DxvkError& e) {
@@ -927,7 +928,6 @@ namespace dxvk {
     presenterDesc.fullScreenExclusive = PickFullscreenMode();
 
     m_wctx->presenter = new Presenter(m_device, m_wctx->frameLatencySignal, presenterDesc);
-    m_wctx->presenter->setFrameRateLimit(m_parent->GetOptions()->maxFrameRate);
   }
 
 
@@ -1107,6 +1107,17 @@ namespace dxvk {
   }
 
 
+  void D3D9SwapChainEx::UpdateTargetFrameRate(uint32_t SyncInterval) {
+    double frameRateOption = double(m_parent->GetOptions()->maxFrameRate);
+    double frameRate = std::max(frameRateOption, 0.0);
+
+    if (SyncInterval && frameRateOption == 0.0)
+      frameRate = -m_displayRefreshRate / double(SyncInterval);
+
+    m_wctx->presenter->setFrameRateLimit(frameRate);
+  }
+
+
   void D3D9SwapChainEx::SyncFrameLatency() {
     // Wait for the sync event so that we respect the maximum frame latency
     m_wctx->frameLatencySignal->wait(m_wctx->frameId - GetActualFrameLatency());
diff --git a/src/d3d9/d3d9_swapchain.h b/src/d3d9/d3d9_swapchain.h
index c6cfef27d..325ba18a1 100644
--- a/src/d3d9/d3d9_swapchain.h
+++ b/src/d3d9/d3d9_swapchain.h
@@ -213,6 +213,8 @@ namespace dxvk {
 
     void InitRamp();
 
+    void UpdateTargetFrameRate(uint32_t SyncInterval);
+
     uint32_t GetActualFrameLatency();
 
     uint32_t PickFormats(