From 5f42950650c56b482bc3bc2c80842877e7d66402 Mon Sep 17 00:00:00 2001
From: Philip Rebohle <philip.rebohle@tu-dortmund.de>
Date: Sun, 26 Aug 2018 23:39:53 +0200
Subject: [PATCH] [dxgi] Don't use FIFO present mode if IMMEDIATE is not
 available

Might fix potential performance issues on Nvidia when VSYNC is disabled.
Based on RPCS3/rpcs3@25ec3789fe6a7835b8c3c189cb93ab7575e18db9
---
 src/dxgi/dxgi_presenter.cpp | 19 +++++++++++++++----
 src/dxgi/dxgi_presenter.h   |  6 +++---
 src/dxgi/dxgi_swapchain.cpp |  6 +-----
 3 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/dxgi/dxgi_presenter.cpp b/src/dxgi/dxgi_presenter.cpp
index accc0f08..260324da 100644
--- a/src/dxgi/dxgi_presenter.cpp
+++ b/src/dxgi/dxgi_presenter.cpp
@@ -293,13 +293,13 @@ namespace dxvk {
   }
   
   
-  void DxgiVkPresenter::RecreateSwapchain(DXGI_FORMAT Format, VkPresentModeKHR PresentMode, VkExtent2D WindowSize) {
+  void DxgiVkPresenter::RecreateSwapchain(DXGI_FORMAT Format, BOOL Vsync, VkExtent2D WindowSize) {
     if (m_surface == nullptr)
       m_surface = CreateSurface();
     
     DxvkSwapchainProperties options;
     options.preferredSurfaceFormat  = PickSurfaceFormat(Format);
-    options.preferredPresentMode    = PickPresentMode(PresentMode);
+    options.preferredPresentMode    = PickPresentMode(Vsync);
     options.preferredBufferSize     = WindowSize;
     
     const bool doRecreate =
@@ -360,8 +360,19 @@ namespace dxvk {
   }
   
   
-  VkPresentModeKHR DxgiVkPresenter::PickPresentMode(VkPresentModeKHR Preferred) const {
-    return m_surface->pickPresentMode(1, &Preferred);
+  VkPresentModeKHR DxgiVkPresenter::PickPresentMode(BOOL Vsync) const {
+    std::array<VkPresentModeKHR, 4> modes;
+    size_t n = 0;
+    
+    if (Vsync) {
+      modes[n++] = VK_PRESENT_MODE_FIFO_KHR;
+    } else {
+      modes[n++] = VK_PRESENT_MODE_IMMEDIATE_KHR;
+      modes[n++] = VK_PRESENT_MODE_MAILBOX_KHR;
+      modes[n++] = VK_PRESENT_MODE_FIFO_RELAXED_KHR;
+    }
+    
+    return m_surface->pickPresentMode(n, modes.data());
   }
   
   
diff --git a/src/dxgi/dxgi_presenter.h b/src/dxgi/dxgi_presenter.h
index 11f4afae..73e4e239 100644
--- a/src/dxgi/dxgi_presenter.h
+++ b/src/dxgi/dxgi_presenter.h
@@ -103,12 +103,12 @@ namespace dxvk {
      * if any of the properties have changed. If no
      * properties have changed, this is a no-op.
      * \param [in] Format New surface format
-     * \param [in] PresentMode Present mode
+     * \param [in] Vsync Enable vertical sync
      * \param [in] WindowSize Window size
      */
     void RecreateSwapchain(
             DXGI_FORMAT       Format,
-            VkPresentModeKHR  PresentMode,
+            BOOL              Vsync,
             VkExtent2D        WindowSize);
     
     /**
@@ -164,7 +164,7 @@ namespace dxvk {
     
     VkSurfaceFormatKHR PickSurfaceFormat(DXGI_FORMAT Fmt) const;
     
-    VkPresentModeKHR PickPresentMode(VkPresentModeKHR Preferred) const;
+    VkPresentModeKHR PickPresentMode(BOOL Vsync) const;
     
     Rc<DxvkSurface> CreateSurface();
     
diff --git a/src/dxgi/dxgi_swapchain.cpp b/src/dxgi/dxgi_swapchain.cpp
index 304b1bbe..a9245d7c 100644
--- a/src/dxgi/dxgi_swapchain.cpp
+++ b/src/dxgi/dxgi_swapchain.cpp
@@ -298,11 +298,7 @@ namespace dxvk {
       // up vertical synchronization properly, but also apply
       // changes that were made to the window size even if the
       // Vulkan swap chain itself remains valid.
-      VkPresentModeKHR presentMode = SyncInterval == 0
-        ? VK_PRESENT_MODE_IMMEDIATE_KHR
-        : VK_PRESENT_MODE_FIFO_KHR;
-      
-      m_presenter->RecreateSwapchain(m_desc.Format, presentMode, GetWindowSize());
+      m_presenter->RecreateSwapchain(m_desc.Format, SyncInterval != 0, GetWindowSize());
       m_presenter->PresentImage(SyncInterval, m_device->GetFrameSyncEvent());
       return S_OK;
     } catch (const DxvkError& err) {