From 3c1e8abcfe0e4404e21074e9db6a4770502f8b0c Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Sat, 29 Feb 2020 22:27:00 -0800
Subject: [PATCH 1/4] GPU: Centralize vsync interval logic.

We already do unthrottle checking here.
---
 GPU/D3D11/GPU_D3D11.cpp       |  1 -
 GPU/D3D11/GPU_D3D11.h         |  2 --
 GPU/Directx9/GPU_DX9.cpp      | 11 -----------
 GPU/Directx9/GPU_DX9.h        |  2 --
 GPU/GLES/GPU_GLES.cpp         | 32 +-------------------------------
 GPU/GLES/GPU_GLES.h           |  6 ------
 GPU/GPUCommon.cpp             | 27 +++++++++++++++++++++++++++
 GPU/GPUCommon.h               |  5 +++++
 GPU/Vulkan/GPU_Vulkan.cpp     |  5 -----
 GPU/Vulkan/GPU_Vulkan.h       |  1 -
 ext/native/gfx/d3d9_state.cpp |  3 ---
 ext/native/gfx/d3d9_state.h   |  3 ---
 12 files changed, 33 insertions(+), 65 deletions(-)

diff --git a/GPU/D3D11/GPU_D3D11.cpp b/GPU/D3D11/GPU_D3D11.cpp
index 9f2c4474e9de..7b5aca935a2b 100644
--- a/GPU/D3D11/GPU_D3D11.cpp
+++ b/GPU/D3D11/GPU_D3D11.cpp
@@ -73,7 +73,6 @@ GPU_D3D11::GPU_D3D11(GraphicsContext *gfxCtx, Draw::DrawContext *draw)
 	device_ = (ID3D11Device *)draw->GetNativeObject(Draw::NativeObject::DEVICE);
 	context_ = (ID3D11DeviceContext *)draw->GetNativeObject(Draw::NativeObject::CONTEXT);
 	D3D_FEATURE_LEVEL featureLevel = (D3D_FEATURE_LEVEL)draw->GetNativeObject(Draw::NativeObject::FEATURE_LEVEL);
-	lastVsync_ = g_Config.bVSync ? 1 : 0;
 
 	stockD3D11.Create(device_);
 
diff --git a/GPU/D3D11/GPU_D3D11.h b/GPU/D3D11/GPU_D3D11.h
index 781cc5f1fbfe..0d16020013cb 100644
--- a/GPU/D3D11/GPU_D3D11.h
+++ b/GPU/D3D11/GPU_D3D11.h
@@ -81,6 +81,4 @@ class GPU_D3D11 : public GPUCommon {
 	DepalShaderCacheD3D11 *depalShaderCache_;
 	DrawEngineD3D11 drawEngine_;
 	ShaderManagerD3D11 *shaderManagerD3D11_;
-
-	int lastVsync_;
 };
diff --git a/GPU/Directx9/GPU_DX9.cpp b/GPU/Directx9/GPU_DX9.cpp
index f54bd4e0717c..70d1d3f4e304 100644
--- a/GPU/Directx9/GPU_DX9.cpp
+++ b/GPU/Directx9/GPU_DX9.cpp
@@ -58,8 +58,6 @@ GPU_DX9::GPU_DX9(GraphicsContext *gfxCtx, Draw::DrawContext *draw)
 		drawEngine_(draw) {
 	device_ = (LPDIRECT3DDEVICE9)draw->GetNativeObject(Draw::NativeObject::DEVICE);
 	deviceEx_ = (LPDIRECT3DDEVICE9EX)draw->GetNativeObject(Draw::NativeObject::DEVICE_EX);
-	lastVsync_ = g_Config.bVSync ? 1 : 0;
-	dxstate.SetVSyncInterval(g_Config.bVSync);
 
 	shaderManagerDX9_ = new ShaderManagerDX9(draw, device_);
 	framebufferManagerDX9_ = new FramebufferManagerDX9(draw);
@@ -285,15 +283,6 @@ void GPU_DX9::ReapplyGfxState() {
 }
 
 void GPU_DX9::BeginFrame() {
-	// Turn off vsync when unthrottled
-	int desiredVSyncInterval = g_Config.bVSync ? 1 : 0;
-	if (PSP_CoreParameter().unthrottle || PSP_CoreParameter().fpsLimit != FPSLimit::NORMAL)
-		desiredVSyncInterval = 0;
-	if (desiredVSyncInterval != lastVsync_) {
-		dxstate.SetVSyncInterval(desiredVSyncInterval);
-		lastVsync_ = desiredVSyncInterval;
-	}
-
 	textureCacheDX9_->StartFrame();
 	drawEngine_.DecimateTrackedVertexArrays();
 	depalShaderCache_.Decimate();
diff --git a/GPU/Directx9/GPU_DX9.h b/GPU/Directx9/GPU_DX9.h
index 5bf58fd1363c..ac5407362a78 100644
--- a/GPU/Directx9/GPU_DX9.h
+++ b/GPU/Directx9/GPU_DX9.h
@@ -80,8 +80,6 @@ class GPU_DX9 : public GPUCommon {
 	DepalShaderCacheDX9 depalShaderCache_;
 	DrawEngineDX9 drawEngine_;
 	ShaderManagerDX9 *shaderManagerDX9_;
-
-	int lastVsync_;
 };
 
 }  // namespace DX9
diff --git a/GPU/GLES/GPU_GLES.cpp b/GPU/GLES/GPU_GLES.cpp
index 97b0ecf17849..b29635d7b389 100644
--- a/GPU/GLES/GPU_GLES.cpp
+++ b/GPU/GLES/GPU_GLES.cpp
@@ -360,6 +360,7 @@ void GPU_GLES::BeginHostFrame() {
 		drawEngine_.Resized();
 		shaderManagerGL_->DirtyShader();
 		textureCacheGL_->NotifyConfigChanged();
+		resized_ = false;
 	}
 
 	drawEngine_.BeginFrame();
@@ -369,42 +370,11 @@ void GPU_GLES::EndHostFrame() {
 	drawEngine_.EndFrame();
 }
 
-inline void GPU_GLES::UpdateVsyncInterval(bool force) {
-#ifdef _WIN32
-	int desiredVSyncInterval = g_Config.bVSync ? 1 : 0;
-	if (PSP_CoreParameter().unthrottle) {
-		desiredVSyncInterval = 0;
-	}
-	if (PSP_CoreParameter().fpsLimit != FPSLimit::NORMAL) {
-		int limit = PSP_CoreParameter().fpsLimit == FPSLimit::CUSTOM1 ? g_Config.iFpsLimit1 : g_Config.iFpsLimit2;
-		// For an alternative speed that is a clean factor of 60, the user probably still wants vsync.
-		if (limit == 0 || (limit >= 0 && limit != 15 && limit != 30 && limit != 60)) {
-			desiredVSyncInterval = 0;
-		}
-	}
-
-	if (desiredVSyncInterval != lastVsync_ || force) {
-		// Disabled EXT_swap_control_tear for now, it never seems to settle at the correct timing
-		// so it just keeps tearing. Not what I hoped for...
-		//if (gl_extensions.EXT_swap_control_tear) {
-		//	// See http://developer.download.nvidia.com/opengl/specs/WGL_EXT_swap_control_tear.txt
-		//	glstate.SetVSyncInterval(-desiredVSyncInterval);
-		//} else {
-		gfxCtx_->SwapInterval(desiredVSyncInterval);
-		//}
-		lastVsync_ = desiredVSyncInterval;
-	}
-#endif
-}
-
 void GPU_GLES::ReapplyGfxState() {
 	GPUCommon::ReapplyGfxState();
 }
 
 void GPU_GLES::BeginFrame() {
-	UpdateVsyncInterval(resized_);
-	resized_ = false;
-
 	textureCacheGL_->StartFrame();
 	drawEngine_.DecimateTrackedVertexArrays();
 	depalShaderCache_.Decimate();
diff --git a/GPU/GLES/GPU_GLES.h b/GPU/GLES/GPU_GLES.h
index 9aa78825c179..351a3ea16728 100644
--- a/GPU/GLES/GPU_GLES.h
+++ b/GPU/GLES/GPU_GLES.h
@@ -79,8 +79,6 @@ class GPU_GLES : public GPUCommon {
 	void CopyDisplayToOutput() override;
 	void Reinitialize() override;
 
-	inline void UpdateVsyncInterval(bool force);
-
 	FramebufferManagerGLES *framebufferManagerGL_;
 	TextureCacheGLES *textureCacheGL_;
 	DepalShaderCacheGLES depalShaderCache_;
@@ -89,8 +87,4 @@ class GPU_GLES : public GPUCommon {
 	ShaderManagerGLES *shaderManagerGL_;
 
 	std::string shaderCachePath_;
-
-#ifdef _WIN32
-	int lastVsync_;
-#endif
 };
diff --git a/GPU/GPUCommon.cpp b/GPU/GPUCommon.cpp
index 649a37f4d1b6..d82964d7fb6a 100644
--- a/GPU/GPUCommon.cpp
+++ b/GPU/GPUCommon.cpp
@@ -6,6 +6,7 @@
 #include "profiler/profiler.h"
 
 #include "Common/ColorConv.h"
+#include "Common/GraphicsContext.h"
 #include "Core/Reporting.h"
 #include "GPU/GeDisasm.h"
 #include "GPU/GPU.h"
@@ -408,6 +409,7 @@ GPUCommon::GPUCommon(GraphicsContext *gfxCtx, Draw::DrawContext *draw) :
 	}
 
 	UpdateCmdInfo();
+	UpdateVsyncInterval(true);
 }
 
 GPUCommon::~GPUCommon() {
@@ -432,6 +434,7 @@ void GPUCommon::UpdateCmdInfo() {
 }
 
 void GPUCommon::BeginHostFrame() {
+	UpdateVsyncInterval(resized_);
 	ReapplyGfxState();
 
 	// TODO: Assume config may have changed - maybe move to resize.
@@ -458,6 +461,30 @@ void GPUCommon::Reinitialize() {
 	interruptsEnabled_ = true;
 }
 
+void GPUCommon::UpdateVsyncInterval(bool force) {
+#ifdef _WIN32
+	int desiredVSyncInterval = g_Config.bVSync ? 1 : 0;
+	if (PSP_CoreParameter().unthrottle) {
+		desiredVSyncInterval = 0;
+	}
+	if (PSP_CoreParameter().fpsLimit != FPSLimit::NORMAL) {
+		int limit = PSP_CoreParameter().fpsLimit == FPSLimit::CUSTOM1 ? g_Config.iFpsLimit1 : g_Config.iFpsLimit2;
+		// For an alternative speed that is a clean factor of 60, the user probably still wants vsync.
+		if (limit == 0 || (limit >= 0 && limit != 15 && limit != 30 && limit != 60)) {
+			desiredVSyncInterval = 0;
+		}
+	}
+
+	if (desiredVSyncInterval != lastVsync_ || force) {
+		// Disabled EXT_swap_control_tear for now, it never seems to settle at the correct timing
+		// so it just keeps tearing. Not what I hoped for... (gl_extensions.EXT_swap_control_tear)
+		// See http://developer.download.nvidia.com/opengl/specs/WGL_EXT_swap_control_tear.txt
+		gfxCtx_->SwapInterval(desiredVSyncInterval);
+		lastVsync_ = desiredVSyncInterval;
+	}
+#endif
+}
+
 int GPUCommon::EstimatePerVertexCost() {
 	// TODO: This is transform cost, also account for rasterization cost somehow... although it probably
 	// runs in parallel with transform.
diff --git a/GPU/GPUCommon.h b/GPU/GPUCommon.h
index ff7236fb9192..17681cc55eeb 100644
--- a/GPU/GPUCommon.h
+++ b/GPU/GPUCommon.h
@@ -276,6 +276,7 @@ class GPUCommon : public GPUInterface, public GPUDebugInterface {
 	}
 
 	void BeginFrame() override;
+	void UpdateVsyncInterval(bool force);
 
 	virtual void FastRunLoop(DisplayList &list);
 
@@ -362,6 +363,10 @@ class GPUCommon : public GPUInterface, public GPUDebugInterface {
 	// Debug stats.
 	double timeSteppingStarted_;
 	double timeSpentStepping_;
+
+#ifdef _WIN32
+	int lastVsync_;
+#endif
 };
 
 struct CommonCommandTableEntry {
diff --git a/GPU/Vulkan/GPU_Vulkan.cpp b/GPU/Vulkan/GPU_Vulkan.cpp
index 3f20ec064210..2bb2bb33f6b7 100644
--- a/GPU/Vulkan/GPU_Vulkan.cpp
+++ b/GPU/Vulkan/GPU_Vulkan.cpp
@@ -57,7 +57,6 @@ GPU_Vulkan::GPU_Vulkan(GraphicsContext *gfxCtx, Draw::DrawContext *draw)
 		drawEngine_(vulkan_, draw),
 		depalShaderCache_(draw, vulkan_),
 		vulkan2D_(vulkan_) {
-	UpdateVsyncInterval(true);
 	CheckGPUFeatures();
 
 	shaderManagerVulkan_ = new ShaderManagerVulkan(draw, vulkan_);
@@ -419,10 +418,6 @@ void GPU_Vulkan::InitClear() {
 	}
 }
 
-void GPU_Vulkan::UpdateVsyncInterval(bool force) {
-	// TODO
-}
-
 void GPU_Vulkan::SetDisplayFramebuffer(u32 framebuf, u32 stride, GEBufferFormat format) {
 	GPUDebug::NotifyDisplay(framebuf, stride, format);
 	framebufferManager_->SetDisplayFramebuffer(framebuf, stride, format);
diff --git a/GPU/Vulkan/GPU_Vulkan.h b/GPU/Vulkan/GPU_Vulkan.h
index bb2efe587706..d1c10c537012 100644
--- a/GPU/Vulkan/GPU_Vulkan.h
+++ b/GPU/Vulkan/GPU_Vulkan.h
@@ -80,7 +80,6 @@ class GPU_Vulkan : public GPUCommon {
 	void InitClear() override;
 	void CopyDisplayToOutput() override;
 	void Reinitialize() override;
-	inline void UpdateVsyncInterval(bool force);
 
 	void InitDeviceObjects();
 	void DestroyDeviceObjects();
diff --git a/ext/native/gfx/d3d9_state.cpp b/ext/native/gfx/d3d9_state.cpp
index fe7849b894e6..14887f7f1767 100644
--- a/ext/native/gfx/d3d9_state.cpp
+++ b/ext/native/gfx/d3d9_state.cpp
@@ -73,9 +73,6 @@ void CheckGLExtensions() {
 	memset(&gl_extensions, 0, sizeof(gl_extensions));
 }
 
-void DirectXState::SetVSyncInterval(int interval) {
-}
-
 }  // namespace DX9
 
 #endif  // _MSC_VER
diff --git a/ext/native/gfx/d3d9_state.h b/ext/native/gfx/d3d9_state.h
index 3304c22a1e81..a15683451717 100644
--- a/ext/native/gfx/d3d9_state.h
+++ b/ext/native/gfx/d3d9_state.h
@@ -484,9 +484,6 @@ class DirectXState {
 	DxSampler0State1<D3DSAMP_MAXMIPLEVEL, 0> texMaxMipLevel;
 	DxSampler0State1<D3DSAMP_ADDRESSU, D3DTADDRESS_CLAMP> texAddressU;
 	DxSampler0State1<D3DSAMP_ADDRESSV, D3DTADDRESS_CLAMP> texAddressV;
-
-	// Only works on Win32, all other platforms are "force-vsync"
-	void SetVSyncInterval(int interval);  // one of the above VSYNC, or a higher number for multi-frame waits (could be useful for 30hz games)
 };
 
 #undef STATE1

From 2a3fd05651df874f5a0f1ed149dff0c203687ca2 Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Sat, 29 Feb 2020 22:45:18 -0800
Subject: [PATCH 2/4] Vulkan: Present using FIFO for vsync.

This allows the setting to be changed at runtime in Vulkan too.

Should help #10105.
---
 Common/Vulkan/VulkanContext.cpp      | 21 +++++++++------------
 Common/Vulkan/VulkanContext.h        |  2 ++
 Core/HLE/sceDisplay.cpp              |  7 ++++++-
 UI/GameSettingsScreen.cpp            |  6 +++++-
 Windows/GPU/WindowsVulkanContext.cpp | 15 +++++++++++----
 Windows/MainWindowMenu.cpp           |  1 +
 android/jni/AndroidVulkanContext.cpp | 11 +++++++++--
 7 files changed, 43 insertions(+), 20 deletions(-)

diff --git a/Common/Vulkan/VulkanContext.cpp b/Common/Vulkan/VulkanContext.cpp
index cb4dc0b33a09..ca1e5dec19c4 100644
--- a/Common/Vulkan/VulkanContext.cpp
+++ b/Common/Vulkan/VulkanContext.cpp
@@ -949,20 +949,17 @@ bool VulkanContext::InitSwapchain() {
 		ILOG("Supported present mode: %d (%s)", presentModes[i], PresentModeString(presentModes[i]));
 	}
 	for (size_t i = 0; i < presentModeCount; i++) {
-		if (swapchainPresentMode == VK_PRESENT_MODE_MAX_ENUM_KHR) {
-			// Default to the first present mode from the list.
+		bool match = false;
+		match = match || ((flags_ & VULKAN_FLAG_PRESENT_MAILBOX) && presentModes[i] == VK_PRESENT_MODE_MAILBOX_KHR);
+		match = match || ((flags_ & VULKAN_FLAG_PRESENT_FIFO_RELAXED) && presentModes[i] == VK_PRESENT_MODE_FIFO_RELAXED_KHR);
+		match = match || ((flags_ & VULKAN_FLAG_PRESENT_FIFO) && presentModes[i] == VK_PRESENT_MODE_FIFO_KHR);
+		match = match || ((flags_ & VULKAN_FLAG_PRESENT_IMMEDIATE) && presentModes[i] == VK_PRESENT_MODE_IMMEDIATE_KHR);
+
+		// Default to the first present mode from the list.
+		if (match || swapchainPresentMode == VK_PRESENT_MODE_MAX_ENUM_KHR) {
 			swapchainPresentMode = presentModes[i];
 		}
-		if ((flags_ & VULKAN_FLAG_PRESENT_MAILBOX) && presentModes[i] == VK_PRESENT_MODE_MAILBOX_KHR) {
-			swapchainPresentMode = VK_PRESENT_MODE_MAILBOX_KHR;
-			break;
-		}
-		if ((flags_ & VULKAN_FLAG_PRESENT_FIFO_RELAXED) && presentModes[i] == VK_PRESENT_MODE_FIFO_RELAXED_KHR) {
-			swapchainPresentMode = VK_PRESENT_MODE_FIFO_RELAXED_KHR;
-			break;
-		}
-		if ((flags_ & VULKAN_FLAG_PRESENT_IMMEDIATE) && presentModes[i] == VK_PRESENT_MODE_IMMEDIATE_KHR) {
-			swapchainPresentMode = VK_PRESENT_MODE_IMMEDIATE_KHR;
+		if (match) {
 			break;
 		}
 	}
diff --git a/Common/Vulkan/VulkanContext.h b/Common/Vulkan/VulkanContext.h
index fccc3dc98e10..f08d883ceb9c 100644
--- a/Common/Vulkan/VulkanContext.h
+++ b/Common/Vulkan/VulkanContext.h
@@ -13,6 +13,7 @@ enum {
 	VULKAN_FLAG_PRESENT_MAILBOX = 2,
 	VULKAN_FLAG_PRESENT_IMMEDIATE = 4,
 	VULKAN_FLAG_PRESENT_FIFO_RELAXED = 8,
+	VULKAN_FLAG_PRESENT_FIFO = 16,
 };
 
 enum {
@@ -136,6 +137,7 @@ class VulkanContext {
 	VkDevice GetDevice() const { return device_; }
 	VkInstance GetInstance() const { return instance_; }
 	uint32_t GetFlags() const { return flags_; }
+	void UpdateFlags(uint32_t flags) { flags_ = flags; }
 
 	VulkanDeleteList &Delete() { return globalDeleteList_; }
 
diff --git a/Core/HLE/sceDisplay.cpp b/Core/HLE/sceDisplay.cpp
index 972e2e759fe4..41834a7f334c 100644
--- a/Core/HLE/sceDisplay.cpp
+++ b/Core/HLE/sceDisplay.cpp
@@ -553,7 +553,12 @@ static void DoFrameTiming(bool &throttle, bool &skipFrame, float timestep) {
 	// we have nothing to do here.
 	bool doFrameSkip = g_Config.iFrameSkip != 0;
 
-	if (!throttle && g_Config.bFrameSkipUnthrottle) {
+	bool unthrottleNeedsSkip = g_Config.bFrameSkipUnthrottle;
+	if (g_Config.bVSync && GetGPUBackend() == GPUBackend::VULKAN) {
+		// Vulkan doesn't support the interval setting, so we force frameskip.
+		unthrottleNeedsSkip = true;
+	}
+	if (!throttle && unthrottleNeedsSkip) {
 		doFrameSkip = true;
 		skipFrame = true;
 		if (numSkippedFrames >= 7) {
diff --git a/UI/GameSettingsScreen.cpp b/UI/GameSettingsScreen.cpp
index a6fae59fa451..4cdec193e6ba 100644
--- a/UI/GameSettingsScreen.cpp
+++ b/UI/GameSettingsScreen.cpp
@@ -342,7 +342,11 @@ void GameSettingsScreen::CreateViews() {
 #endif
 
 #ifdef _WIN32
-	graphicsSettings->Add(new CheckBox(&g_Config.bVSync, gr->T("VSync")));
+	CheckBox *vSync = graphicsSettings->Add(new CheckBox(&g_Config.bVSync, gr->T("VSync")));
+	vSync->OnClick.Add([=](EventParams &e) {
+		NativeResized();
+		return UI::EVENT_CONTINUE;
+	});
 #endif
 
 	CheckBox *hwTransform = graphicsSettings->Add(new CheckBox(&g_Config.bHardwareTransform, gr->T("Hardware Transform")));
diff --git a/Windows/GPU/WindowsVulkanContext.cpp b/Windows/GPU/WindowsVulkanContext.cpp
index 7797b58289a5..772d03798997 100644
--- a/Windows/GPU/WindowsVulkanContext.cpp
+++ b/Windows/GPU/WindowsVulkanContext.cpp
@@ -74,6 +74,15 @@ static VulkanContext *g_Vulkan;
 
 static VulkanLogOptions g_LogOptions;
 
+static uint32_t FlagsFromConfig() {
+	uint32_t flags = 0;
+	flags = g_Config.bVSync ? VULKAN_FLAG_PRESENT_FIFO : VULKAN_FLAG_PRESENT_MAILBOX;
+	if (g_validate_) {
+		flags |= VULKAN_FLAG_VALIDATE;
+	}
+	return flags;
+}
+
 bool WindowsVulkanContext::Init(HINSTANCE hInst, HWND hWnd, std::string *error_message) {
 	*error_message = "N/A";
 
@@ -100,10 +109,7 @@ bool WindowsVulkanContext::Init(HINSTANCE hInst, HWND hWnd, std::string *error_m
 	VulkanContext::CreateInfo info{};
 	info.app_name = "PPSSPP";
 	info.app_ver = gitVer.ToInteger();
-	info.flags = VULKAN_FLAG_PRESENT_MAILBOX;
-	if (g_validate_) {
-		info.flags |= VULKAN_FLAG_VALIDATE;
-	}
+	info.flags = FlagsFromConfig();
 	if (VK_SUCCESS != g_Vulkan->CreateInstance(info)) {
 		*error_message = g_Vulkan->InitError();
 		delete g_Vulkan;
@@ -184,6 +190,7 @@ void WindowsVulkanContext::Resize() {
 	draw_->HandleEvent(Draw::Event::LOST_BACKBUFFER, g_Vulkan->GetBackbufferWidth(), g_Vulkan->GetBackbufferHeight());
 	g_Vulkan->DestroyObjects();
 
+	g_Vulkan->UpdateFlags(FlagsFromConfig());
 	g_Vulkan->ReinitSurface();
 
 	g_Vulkan->InitObjects();
diff --git a/Windows/MainWindowMenu.cpp b/Windows/MainWindowMenu.cpp
index 225e3ce681ba..32861c90f221 100644
--- a/Windows/MainWindowMenu.cpp
+++ b/Windows/MainWindowMenu.cpp
@@ -739,6 +739,7 @@ namespace MainWindow {
 
 		case ID_OPTIONS_VSYNC:
 			g_Config.bVSync = !g_Config.bVSync;
+			NativeResized();
 			break;
 
 		case ID_OPTIONS_FRAMESKIP_AUTO:
diff --git a/android/jni/AndroidVulkanContext.cpp b/android/jni/AndroidVulkanContext.cpp
index 71c63077b6b0..1ff51b5f6773 100644
--- a/android/jni/AndroidVulkanContext.cpp
+++ b/android/jni/AndroidVulkanContext.cpp
@@ -81,6 +81,13 @@ AndroidVulkanContext::~AndroidVulkanContext() {
 	g_Vulkan = nullptr;
 }
 
+static uint32_t FlagsFromConfig() {
+	if (g_Config.bVSync) {
+		return VULKAN_FLAG_PRESENT_FIFO;
+	}
+	return VULKAN_FLAG_PRESENT_MAILBOX | VULKAN_FLAG_PRESENT_FIFO_RELAXED;
+}
+
 bool AndroidVulkanContext::InitAPI() {
 	ILOG("AndroidVulkanContext::Init");
 	init_glslang();
@@ -105,7 +112,7 @@ bool AndroidVulkanContext::InitAPI() {
 	VulkanContext::CreateInfo info{};
 	info.app_name = "PPSSPP";
 	info.app_ver = gitVer.ToInteger();
-	info.flags = VULKAN_FLAG_PRESENT_MAILBOX | VULKAN_FLAG_PRESENT_FIFO_RELAXED;
+	info.flags = FlagsFromConfig();
 	VkResult res = g_Vulkan->CreateInstance(info);
 	if (res != VK_SUCCESS) {
 		ELOG("Failed to create vulkan context: %s", g_Vulkan->InitError().c_str());
@@ -216,7 +223,7 @@ void AndroidVulkanContext::Resize() {
 	draw_->HandleEvent(Draw::Event::LOST_BACKBUFFER, g_Vulkan->GetBackbufferWidth(), g_Vulkan->GetBackbufferHeight());
 	g_Vulkan->DestroyObjects();
 
-	// backbufferResize updated these values.	TODO: Notify another way?
+	g_Vulkan->UpdateFlags(FlagsFromConfig());
 	g_Vulkan->ReinitSurface();
 	g_Vulkan->InitObjects();
 	draw_->HandleEvent(Draw::Event::GOT_BACKBUFFER, g_Vulkan->GetBackbufferWidth(), g_Vulkan->GetBackbufferHeight());

From 6f86b6fdbef655c9c9959bb421d6cf1ba4187330 Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Sat, 29 Feb 2020 22:47:08 -0800
Subject: [PATCH 3/4] D3D11: Respect vsync setting.

Fixes #12493.
---
 Windows/GPU/D3D11Context.cpp | 4 ++--
 Windows/GPU/D3D11Context.h   | 1 +
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/Windows/GPU/D3D11Context.cpp b/Windows/GPU/D3D11Context.cpp
index c8911e51442e..31b3bcb08673 100644
--- a/Windows/GPU/D3D11Context.cpp
+++ b/Windows/GPU/D3D11Context.cpp
@@ -42,12 +42,12 @@ D3D11Context::~D3D11Context() {
 }
 
 void D3D11Context::SwapBuffers() {
-	swapChain_->Present(0, 0);
+	swapChain_->Present(swapInterval_, 0);
 	draw_->HandleEvent(Draw::Event::PRESENTED, 0, 0, nullptr, nullptr);
 }
 
 void D3D11Context::SwapInterval(int interval) {
-	// Dummy
+	swapInterval_ = interval;
 }
 
 HRESULT D3D11Context::CreateTheDevice(IDXGIAdapter *adapter) {
diff --git a/Windows/GPU/D3D11Context.h b/Windows/GPU/D3D11Context.h
index 88f1547295af..07d551b7ded7 100644
--- a/Windows/GPU/D3D11Context.h
+++ b/Windows/GPU/D3D11Context.h
@@ -67,4 +67,5 @@ class D3D11Context : public WindowsGraphicsContext {
 	HMODULE hD3D11;
 	int width;
 	int height;
+	int swapInterval_ = 0;
 };

From bc90faebf70b996c31a01b9210056fa6b5c7c92c Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Sat, 29 Feb 2020 22:48:32 -0800
Subject: [PATCH 4/4] D3D9: Allow vsync change at runtime.

---
 Windows/GPU/D3D9Context.cpp | 11 +++++++----
 Windows/GPU/D3D9Context.h   |  1 +
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/Windows/GPU/D3D9Context.cpp b/Windows/GPU/D3D9Context.cpp
index 4317fd13285e..2ea38836e024 100644
--- a/Windows/GPU/D3D9Context.cpp
+++ b/Windows/GPU/D3D9Context.cpp
@@ -56,7 +56,7 @@ static void GetRes(HWND hWnd, int &xres, int &yres) {
 }
 
 void D3D9Context::SwapInterval(int interval) {
-	// Dummy
+	swapInterval_ = interval;
 }
 
 bool D3D9Context::Init(HINSTANCE hInst, HWND wnd, std::string *error_message) {
@@ -159,7 +159,7 @@ bool D3D9Context::Init(HINSTANCE hInst, HWND wnd, std::string *error_message) {
 	presentParams_.hDeviceWindow = wnd;
 	presentParams_.EnableAutoDepthStencil = true;
 	presentParams_.AutoDepthStencilFormat = D3DFMT_D24S8;
-	presentParams_.PresentationInterval = (g_Config.bVSync) ? D3DPRESENT_INTERVAL_ONE : D3DPRESENT_INTERVAL_IMMEDIATE;
+	presentParams_.PresentationInterval = swapInterval_ == 1 ? D3DPRESENT_INTERVAL_ONE : D3DPRESENT_INTERVAL_IMMEDIATE;
 
 	if (has9Ex_) {
 		if (windowed && IsWin7OrLater()) {
@@ -205,16 +205,19 @@ void D3D9Context::Resize() {
 	// This should only be called from the emu thread.
 	int xres, yres;
 	GetRes(hWnd_, xres, yres);
+	uint32_t newInterval = swapInterval_ == 1 ? D3DPRESENT_INTERVAL_ONE : D3DPRESENT_INTERVAL_IMMEDIATE;;
 	bool w_changed = presentParams_.BackBufferWidth != xres;
 	bool h_changed = presentParams_.BackBufferHeight != yres;
+	bool i_changed = presentParams_.PresentationInterval != newInterval;
 
-	if (device_ && (w_changed || h_changed)) {
+	if (device_ && (w_changed || h_changed || i_changed)) {
 		draw_->HandleEvent(Draw::Event::LOST_BACKBUFFER, 0, 0, nullptr);
 		presentParams_.BackBufferWidth = xres;
 		presentParams_.BackBufferHeight = yres;
+		presentParams_.PresentationInterval = newInterval;
 		HRESULT hr = device_->Reset(&presentParams_);
 		if (FAILED(hr)) {
-      // Had to remove DXGetErrorStringA calls here because dxerr.lib is deprecated and will not link with VS 2015.
+			// Had to remove DXGetErrorStringA calls here because dxerr.lib is deprecated and will not link with VS 2015.
 			PanicAlert("Unable to reset D3D9 device");
 		}
 		draw_->HandleEvent(Draw::Event::GOT_BACKBUFFER, 0, 0, nullptr);
diff --git a/Windows/GPU/D3D9Context.h b/Windows/GPU/D3D9Context.h
index 474137bb7dbc..9ad836d338d3 100644
--- a/Windows/GPU/D3D9Context.h
+++ b/Windows/GPU/D3D9Context.h
@@ -53,5 +53,6 @@ class D3D9Context : public WindowsGraphicsContext {
 	HWND hWnd_;   // Holds Our Window Handle
 	HMODULE hD3D9_;
 	D3DPRESENT_PARAMETERS presentParams_;
+	int swapInterval_ = 0;
 };