path: root/external/skia/share-grcontext.patch.1

diff --git a/tools/sk_app/VulkanWindowContext.cpp b/tools/sk_app/VulkanWindowContext.cpp
index 970c67ec0c..371bd8ab0c 100644
--- a/tools/sk_app/VulkanWindowContext.cpp
+++ b/tools/sk_app/VulkanWindowContext.cpp
@@ -24,8 +24,10 @@
 #undef CreateSemaphore
 #endif
 
-#define GET_PROC(F) f ## F = (PFN_vk ## F) fGetInstanceProcAddr(fInstance, "vk" #F)
-#define GET_DEV_PROC(F) f ## F = (PFN_vk ## F) fGetDeviceProcAddr(fDevice, "vk" #F)
+#define GET_PROC(F) f ## F = (PFN_vk ## F) fGetInstanceProcAddr(fShared->fInstance, "vk" #F)
+#define GET_DEV_PROC(F) f ## F = (PFN_vk ## F) fGetDeviceProcAddr(fShared->fDevice, "vk" #F)
+#define GET_PROC_GLOBAL(F) fGlobalShared->f ## F = (PFN_vk ## F) fGetInstanceProcAddr(fGlobalShared->fInstance, "vk" #F)
+#define GET_DEV_PROC_GLOBAL(F) fGlobalShared->f ## F = (PFN_vk ## F) fGetDeviceProcAddr(fGlobalShared->fDevice, "vk" #F)
 
 namespace sk_app {
 
@@ -49,6 +51,14 @@ VulkanWindowContext::VulkanWindowContext(const DisplayParams& params,
 }
 
 void VulkanWindowContext::initializeContext() {
+    fShared = fGlobalShared;
+    if( !fShared )
+    {
+    // TODO do we need a mutex?
+
+    fGlobalShared = sk_make_sp<Shared>();
+    Shared* d = fGlobalShared.get(); // shorter variable name
+
     // any config code here (particularly for msaa)?
 
     PFN_vkGetInstanceProcAddr getInstanceProc = fGetInstanceProcAddr;
@@ -62,24 +72,25 @@ void VulkanWindowContext::initializeContext() {
     };
     GrVkBackendContext backendContext;
     GrVkExtensions extensions;
-    VkPhysicalDeviceFeatures2 features;
-    if (!sk_gpu_test::CreateVkBackendContext(getProc, &backendContext, &extensions, &features,
-                                             &fDebugCallback, &fPresentQueueIndex, fCanPresentFn)) {
-        sk_gpu_test::FreeVulkanFeaturesStructs(&features);
+    if (!sk_gpu_test::CreateVkBackendContext(getProc, &backendContext, &extensions, &d->features,
+                                             &d->fDebugCallback, &d->fPresentQueueIndex, fCanPresentFn)) {
+        sk_gpu_test::FreeVulkanFeaturesStructs(&d->features);
+        fGlobalShared.reset();
         return;
     }
 
     if (!extensions.hasExtension(VK_KHR_SURFACE_EXTENSION_NAME, 25) ||
         !extensions.hasExtension(VK_KHR_SWAPCHAIN_EXTENSION_NAME, 68)) {
-        sk_gpu_test::FreeVulkanFeaturesStructs(&features);
+        sk_gpu_test::FreeVulkanFeaturesStructs(&d->features);
+        fGlobalShared.reset();
         return;
     }
 
-    fInstance = backendContext.fInstance;
-    fPhysicalDevice = backendContext.fPhysicalDevice;
-    fDevice = backendContext.fDevice;
-    fGraphicsQueueIndex = backendContext.fGraphicsQueueIndex;
-    fGraphicsQueue = backendContext.fQueue;
+    d->fInstance = backendContext.fInstance;
+    d->fPhysicalDevice = backendContext.fPhysicalDevice;
+    d->fDevice = backendContext.fDevice;
+    d->fGraphicsQueueIndex = backendContext.fGraphicsQueueIndex;
+    d->fGraphicsQueue = backendContext.fQueue;
 
     PFN_vkGetPhysicalDeviceProperties localGetPhysicalDeviceProperties =
             reinterpret_cast<PFN_vkGetPhysicalDeviceProperties>(
@@ -87,21 +98,30 @@ void VulkanWindowContext::initializeContext() {
                                             backendContext.fInstance,
                                             VK_NULL_HANDLE));
     if (!localGetPhysicalDeviceProperties) {
-        sk_gpu_test::FreeVulkanFeaturesStructs(&features);
+        sk_gpu_test::FreeVulkanFeaturesStructs(&d->features);
+        fGlobalShared.reset();
         return;
     }
-    VkPhysicalDeviceProperties physDeviceProperties;
-    localGetPhysicalDeviceProperties(backendContext.fPhysicalDevice, &physDeviceProperties);
-    uint32_t physDevVersion = physDeviceProperties.apiVersion;
+    localGetPhysicalDeviceProperties(backendContext.fPhysicalDevice, &d->physDeviceProperties);
+    uint32_t physDevVersion = d->physDeviceProperties.apiVersion;
 
-    fInterface.reset(new GrVkInterface(backendContext.fGetProc, fInstance, fDevice,
+    d->fInterface.reset(new GrVkInterface(backendContext.fGetProc, d->fInstance, d->fDevice,
                                        backendContext.fInstanceVersion, physDevVersion,
                                        &extensions));
 
-    GET_PROC(DestroyInstance);
-    if (fDebugCallback != VK_NULL_HANDLE) {
-        GET_PROC(DestroyDebugReportCallbackEXT);
+    d->fContext = GrContext::MakeVulkan(backendContext, fDisplayParams.fGrContextOptions);
+
+    GET_PROC_GLOBAL(DestroyInstance);
+    GET_DEV_PROC_GLOBAL(DestroyDevice);
+    if (fGlobalShared->fDebugCallback != VK_NULL_HANDLE) {
+        GET_PROC_GLOBAL(DestroyDebugReportCallbackEXT);
     }
+
+    fShared = fGlobalShared;
+    } // if( !fShared )
+
+    fContext = fShared->fContext;
+
     GET_PROC(DestroySurfaceKHR);
     GET_PROC(GetPhysicalDeviceSurfaceSupportKHR);
     GET_PROC(GetPhysicalDeviceSurfaceCapabilitiesKHR);
@@ -109,7 +129,6 @@ void VulkanWindowContext::initializeContext() {
     GET_PROC(GetPhysicalDeviceSurfacePresentModesKHR);
     GET_DEV_PROC(DeviceWaitIdle);
     GET_DEV_PROC(QueueWaitIdle);
-    GET_DEV_PROC(DestroyDevice);
     GET_DEV_PROC(CreateSwapchainKHR);
     GET_DEV_PROC(DestroySwapchainKHR);
     GET_DEV_PROC(GetSwapchainImagesKHR);
@@ -117,46 +136,44 @@ void VulkanWindowContext::initializeContext() {
     GET_DEV_PROC(QueuePresentKHR);
     GET_DEV_PROC(GetDeviceQueue);
 
-    fContext = GrContext::MakeVulkan(backendContext, fDisplayParams.fGrContextOptions);
+    // No actual window, used just to create the shared GrContext.
+    if(fCreateVkSurfaceFn == nullptr)
+        return;
 
-    fSurface = fCreateVkSurfaceFn(fInstance);
+    fSurface = fCreateVkSurfaceFn(fShared->fInstance);
     if (VK_NULL_HANDLE == fSurface) {
         this->destroyContext();
-        sk_gpu_test::FreeVulkanFeaturesStructs(&features);
         return;
     }
 
+    // create presentQueue
+    fGetDeviceQueue(fShared->fDevice, fShared->fPresentQueueIndex, 0, &fPresentQueue);
+
     VkBool32 supported;
-    VkResult res = fGetPhysicalDeviceSurfaceSupportKHR(fPhysicalDevice, fPresentQueueIndex,
+    VkResult res = fGetPhysicalDeviceSurfaceSupportKHR(fShared->fPhysicalDevice, fShared->fPresentQueueIndex,
                                                        fSurface, &supported);
     if (VK_SUCCESS != res) {
         this->destroyContext();
-        sk_gpu_test::FreeVulkanFeaturesStructs(&features);
         return;
     }
 
     if (!this->createSwapchain(-1, -1, fDisplayParams)) {
         this->destroyContext();
-        sk_gpu_test::FreeVulkanFeaturesStructs(&features);
         return;
     }
-
-    // create presentQueue
-    fGetDeviceQueue(fDevice, fPresentQueueIndex, 0, &fPresentQueue);
-    sk_gpu_test::FreeVulkanFeaturesStructs(&features);
 }
 
 bool VulkanWindowContext::createSwapchain(int width, int height,
                                           const DisplayParams& params) {
     // check for capabilities
     VkSurfaceCapabilitiesKHR caps;
-    VkResult res = fGetPhysicalDeviceSurfaceCapabilitiesKHR(fPhysicalDevice, fSurface, &caps);
+    VkResult res = fGetPhysicalDeviceSurfaceCapabilitiesKHR(fShared->fPhysicalDevice, fSurface, &caps);
     if (VK_SUCCESS != res) {
         return false;
     }
 
     uint32_t surfaceFormatCount;
-    res = fGetPhysicalDeviceSurfaceFormatsKHR(fPhysicalDevice, fSurface, &surfaceFormatCount,
+    res = fGetPhysicalDeviceSurfaceFormatsKHR(fShared->fPhysicalDevice, fSurface, &surfaceFormatCount,
                                               nullptr);
     if (VK_SUCCESS != res) {
         return false;
@@ -164,14 +181,14 @@ bool VulkanWindowContext::createSwapchain(int width, int height,
 
     SkAutoMalloc surfaceFormatAlloc(surfaceFormatCount * sizeof(VkSurfaceFormatKHR));
     VkSurfaceFormatKHR* surfaceFormats = (VkSurfaceFormatKHR*)surfaceFormatAlloc.get();
-    res = fGetPhysicalDeviceSurfaceFormatsKHR(fPhysicalDevice, fSurface, &surfaceFormatCount,
+    res = fGetPhysicalDeviceSurfaceFormatsKHR(fShared->fPhysicalDevice, fSurface, &surfaceFormatCount,
                                               surfaceFormats);
     if (VK_SUCCESS != res) {
         return false;
     }
 
     uint32_t presentModeCount;
-    res = fGetPhysicalDeviceSurfacePresentModesKHR(fPhysicalDevice, fSurface, &presentModeCount,
+    res = fGetPhysicalDeviceSurfacePresentModesKHR(fShared->fPhysicalDevice, fSurface, &presentModeCount,
                                                    nullptr);
     if (VK_SUCCESS != res) {
         return false;
@@ -179,7 +196,7 @@ bool VulkanWindowContext::createSwapchain(int width, int height,
 
     SkAutoMalloc presentModeAlloc(presentModeCount * sizeof(VkPresentModeKHR));
     VkPresentModeKHR* presentModes = (VkPresentModeKHR*)presentModeAlloc.get();
-    res = fGetPhysicalDeviceSurfacePresentModesKHR(fPhysicalDevice, fSurface, &presentModeCount,
+    res = fGetPhysicalDeviceSurfacePresentModesKHR(fShared->fPhysicalDevice, fSurface, &presentModeCount,
                                                    presentModes);
     if (VK_SUCCESS != res) {
         return false;
@@ -286,8 +303,8 @@ bool VulkanWindowContext::createSwapchain(int width, int height,
     swapchainCreateInfo.imageArrayLayers = 1;
     swapchainCreateInfo.imageUsage = usageFlags;
 
-    uint32_t queueFamilies[] = { fGraphicsQueueIndex, fPresentQueueIndex };
-    if (fGraphicsQueueIndex != fPresentQueueIndex) {
+    uint32_t queueFamilies[] = { fShared->fGraphicsQueueIndex, fShared->fPresentQueueIndex };
+    if (fShared->fGraphicsQueueIndex != fShared->fPresentQueueIndex) {
         swapchainCreateInfo.imageSharingMode = VK_SHARING_MODE_CONCURRENT;
         swapchainCreateInfo.queueFamilyIndexCount = 2;
         swapchainCreateInfo.pQueueFamilyIndices = queueFamilies;
@@ -303,18 +320,18 @@ bool VulkanWindowContext::createSwapchain(int width, int height,
     swapchainCreateInfo.clipped = true;
     swapchainCreateInfo.oldSwapchain = fSwapchain;
 
-    res = fCreateSwapchainKHR(fDevice, &swapchainCreateInfo, nullptr, &fSwapchain);
+    res = fCreateSwapchainKHR(fShared->fDevice, &swapchainCreateInfo, nullptr, &fSwapchain);
     if (VK_SUCCESS != res) {
         return false;
     }
 
     // destroy the old swapchain
     if (swapchainCreateInfo.oldSwapchain != VK_NULL_HANDLE) {
-        fDeviceWaitIdle(fDevice);
+        fDeviceWaitIdle(fShared->fDevice);
 
         this->destroyBuffers();
 
-        fDestroySwapchainKHR(fDevice, swapchainCreateInfo.oldSwapchain, nullptr);
+        fDestroySwapchainKHR(fShared->fDevice, swapchainCreateInfo.oldSwapchain, nullptr);
     }
 
     this->createBuffers(swapchainCreateInfo.imageFormat, colorType,
@@ -325,10 +342,10 @@ bool VulkanWindowContext::createSwapchain(int width, int height,
 
 void VulkanWindowContext::createBuffers(VkFormat format, SkColorType colorType,
                                         VkSharingMode sharingMode) {
-    fGetSwapchainImagesKHR(fDevice, fSwapchain, &fImageCount, nullptr);
+    fGetSwapchainImagesKHR(fShared->fDevice, fSwapchain, &fImageCount, nullptr);
     SkASSERT(fImageCount);
     fImages = new VkImage[fImageCount];
-    fGetSwapchainImagesKHR(fDevice, fSwapchain, &fImageCount, fImages);
+    fGetSwapchainImagesKHR(fShared->fDevice, fSwapchain, &fImageCount, fImages);
 
     // set up initial image layouts and create surfaces
     fImageLayouts = new VkImageLayout[fImageCount];
@@ -343,7 +360,7 @@ void VulkanWindowContext::createBuffers(VkFormat format, SkColorType colorType,
         info.fImageTiling = VK_IMAGE_TILING_OPTIMAL;
         info.fFormat = format;
         info.fLevelCount = 1;
-        info.fCurrentQueueFamily = fPresentQueueIndex;
+        info.fCurrentQueueFamily = fShared->fPresentQueueIndex;
         info.fSharingMode = sharingMode;
 
         if (fSampleCount == 1) {
@@ -375,8 +392,8 @@ void VulkanWindowContext::createBuffers(VkFormat format, SkColorType colorType,
     fBackbuffers = new BackbufferInfo[fImageCount + 1];
     for (uint32_t i = 0; i < fImageCount + 1; ++i) {
         fBackbuffers[i].fImageIndex = -1;
-        SkDEBUGCODE(VkResult result = )GR_VK_CALL(fInterface,
-                CreateSemaphore(fDevice, &semaphoreInfo, nullptr,
+        SkDEBUGCODE(VkResult result = )GR_VK_CALL(fShared->fInterface,
+                CreateSemaphore(fShared->fDevice, &semaphoreInfo, nullptr,
                                 &fBackbuffers[i].fRenderSemaphore));
         SkASSERT(result == VK_SUCCESS);
     }
@@ -388,8 +405,8 @@ void VulkanWindowContext::destroyBuffers() {
     if (fBackbuffers) {
         for (uint32_t i = 0; i < fImageCount + 1; ++i) {
             fBackbuffers[i].fImageIndex = -1;
-            GR_VK_CALL(fInterface,
-                       DestroySemaphore(fDevice,
+            GR_VK_CALL(fShared->fInterface,
+                       DestroySemaphore(fShared->fDevice,
                                         fBackbuffers[i].fRenderSemaphore,
                                         nullptr));
         }
@@ -414,41 +431,59 @@ VulkanWindowContext::~VulkanWindowContext() {
 void VulkanWindowContext::destroyContext() {
     if (this->isValid()) {
         fQueueWaitIdle(fPresentQueue);
-        fDeviceWaitIdle(fDevice);
+        fDeviceWaitIdle(fShared->fDevice);
 
         this->destroyBuffers();
 
         if (VK_NULL_HANDLE != fSwapchain) {
-            fDestroySwapchainKHR(fDevice, fSwapchain, nullptr);
+            fDestroySwapchainKHR(fShared->fDevice, fSwapchain, nullptr);
             fSwapchain = VK_NULL_HANDLE;
         }
 
         if (VK_NULL_HANDLE != fSurface) {
-            fDestroySurfaceKHR(fInstance, fSurface, nullptr);
+            fDestroySurfaceKHR(fShared->fInstance, fSurface, nullptr);
             fSurface = VK_NULL_HANDLE;
         }
     }
 
     fContext.reset();
-    fInterface.reset();
+    fShared.reset();
+
+    checkDestroyShared();
+}
+
+void VulkanWindowContext::checkDestroyShared()
+{
+    if(!fGlobalShared || !fGlobalShared->unique()) // TODO mutex?
+        return;
+#ifndef SK_TRACE_VK_RESOURCES
+    if(!fGlobalShared->fContext->unique())
+        return;
+#endif
+    SkASSERT(fGlobalShared->fContext->unique());
+    fGlobalShared->fContext.reset();
+    fGlobalShared->fInterface.reset();
 
-    if (VK_NULL_HANDLE != fDevice) {
-        fDestroyDevice(fDevice, nullptr);
-        fDevice = VK_NULL_HANDLE;
+    if (VK_NULL_HANDLE != fGlobalShared->fDevice) {
+        fGlobalShared->fDestroyDevice(fGlobalShared->fDevice, nullptr);
+        fGlobalShared->fDevice = VK_NULL_HANDLE;
     }
 
 #ifdef SK_ENABLE_VK_LAYERS
-    if (fDebugCallback != VK_NULL_HANDLE) {
-        fDestroyDebugReportCallbackEXT(fInstance, fDebugCallback, nullptr);
+    if (fGlobalShared->fDebugCallback != VK_NULL_HANDLE) {
+        fGlobalShared->fDestroyDebugReportCallbackEXT(fGlobalShared->fInstance, fDebugCallback, nullptr);
     }
 #endif
 
-    fPhysicalDevice = VK_NULL_HANDLE;
+    fGlobalShared->fPhysicalDevice = VK_NULL_HANDLE;
 
-    if (VK_NULL_HANDLE != fInstance) {
-        fDestroyInstance(fInstance, nullptr);
-        fInstance = VK_NULL_HANDLE;
+    if (VK_NULL_HANDLE != fGlobalShared->fInstance) {
+        fGlobalShared->fDestroyInstance(fGlobalShared->fInstance, nullptr);
+        fGlobalShared->fInstance = VK_NULL_HANDLE;
     }
+
+    sk_gpu_test::FreeVulkanFeaturesStructs(&fGlobalShared->features);
+    fGlobalShared.reset();
 }
 
 VulkanWindowContext::BackbufferInfo* VulkanWindowContext::getAvailableBackbuffer() {
@@ -474,35 +509,35 @@ sk_sp<SkSurface> VulkanWindowContext::getBackbufferSurface() {
     semaphoreInfo.pNext = nullptr;
     semaphoreInfo.flags = 0;
     VkSemaphore semaphore;
-    SkDEBUGCODE(VkResult result = )GR_VK_CALL(fInterface, CreateSemaphore(fDevice, &semaphoreInfo,
+    SkDEBUGCODE(VkResult result = )GR_VK_CALL(fShared->fInterface, CreateSemaphore(fShared->fDevice, &semaphoreInfo,
                                                                           nullptr, &semaphore));
     SkASSERT(result == VK_SUCCESS);
 
     // acquire the image
-    VkResult res = fAcquireNextImageKHR(fDevice, fSwapchain, UINT64_MAX,
+    VkResult res = fAcquireNextImageKHR(fShared->fDevice, fSwapchain, UINT64_MAX,
                                         semaphore, VK_NULL_HANDLE,
                                         &backbuffer->fImageIndex);
     if (VK_ERROR_SURFACE_LOST_KHR == res) {
         // need to figure out how to create a new vkSurface without the platformData*
         // maybe use attach somehow? but need a Window
-        GR_VK_CALL(fInterface, DestroySemaphore(fDevice, semaphore, nullptr));
+        GR_VK_CALL(fShared->fInterface, DestroySemaphore(fShared->fDevice, semaphore, nullptr));
         return nullptr;
     }
     if (VK_ERROR_OUT_OF_DATE_KHR == res) {
         // tear swapchain down and try again
         if (!this->createSwapchain(-1, -1, fDisplayParams)) {
-            GR_VK_CALL(fInterface, DestroySemaphore(fDevice, semaphore, nullptr));
+            GR_VK_CALL(fShared->fInterface, DestroySemaphore(fShared->fDevice, semaphore, nullptr));
             return nullptr;
         }
         backbuffer = this->getAvailableBackbuffer();
 
         // acquire the image
-        res = fAcquireNextImageKHR(fDevice, fSwapchain, UINT64_MAX,
+        res = fAcquireNextImageKHR(fShared->fDevice, fSwapchain, UINT64_MAX,
                                    semaphore, VK_NULL_HANDLE,
                                    &backbuffer->fImageIndex);
 
         if (VK_SUCCESS != res) {
-            GR_VK_CALL(fInterface, DestroySemaphore(fDevice, semaphore, nullptr));
+            GR_VK_CALL(fShared->fInterface, DestroySemaphore(fShared->fDevice, semaphore, nullptr));
             return nullptr;
         }
     }
@@ -528,7 +563,7 @@ void VulkanWindowContext::swapBuffers() {
     GrFlushInfo info;
     info.fNumSemaphores = 1;
     info.fSignalSemaphores = &beSemaphore;
-    GrBackendSurfaceMutableState presentState(VK_IMAGE_LAYOUT_PRESENT_SRC_KHR, fPresentQueueIndex);
+    GrBackendSurfaceMutableState presentState(VK_IMAGE_LAYOUT_PRESENT_SRC_KHR, fShared->fPresentQueueIndex);
     surface->flush(info, &presentState);
     surface->getContext()->submit();
 
@@ -548,4 +583,6 @@ void VulkanWindowContext::swapBuffers() {
     fQueuePresentKHR(fPresentQueue, &presentInfo);
 }
 
+SK_API sk_sp<VulkanWindowContext::Shared> VulkanWindowContext::fGlobalShared;
+
 }   //namespace sk_app
diff --git a/tools/sk_app/VulkanWindowContext.h b/tools/sk_app/VulkanWindowContext.h
index 5e245aff70..c6c866372f 100644
--- a/tools/sk_app/VulkanWindowContext.h
+++ b/tools/sk_app/VulkanWindowContext.h
@@ -19,18 +19,36 @@
 #include "tools/gpu/vk/VkTestUtils.h"
 #include "tools/sk_app/WindowContext.h"
 
+#include <cassert>
+
 class GrRenderTarget;
 
 namespace sk_app {
 
-class VulkanWindowContext : public WindowContext {
+class SK_API VulkanWindowContext : public WindowContext {
+    struct Shared;
 public:
     ~VulkanWindowContext() override;
 
+    class SharedGrContext {
+    public:
+        SharedGrContext() {}
+        GrContext* getGrContext() { return shared ? shared->fContext.get() : nullptr; }
+        ~SharedGrContext() { shared.reset(); checkDestroyShared(); }
+        bool operator!() const { return !shared; }
+        void reset() { shared.reset(); }
+    private:
+        friend class VulkanWindowContext;
+        SharedGrContext(sk_sp<Shared>& sh ) : shared( sh ) {}
+        sk_sp<Shared> shared;
+    };
+
+    static SharedGrContext getSharedGrContext() { return SharedGrContext( fGlobalShared ); }
+
     sk_sp<SkSurface> getBackbufferSurface() override;
     void swapBuffers() override;
 
-    bool isValid() override { return fDevice != VK_NULL_HANDLE; }
+    bool isValid() override { return fSurface != VK_NULL_HANDLE; }
 
     void resize(int w, int h) override {
         this->createSwapchain(w, h, fDisplayParams);
@@ -50,9 +68,15 @@ public:
     VulkanWindowContext(const DisplayParams&, CreateVkSurfaceFn, CanPresentFn,
                         PFN_vkGetInstanceProcAddr, PFN_vkGetDeviceProcAddr);
 
+    static const VkPhysicalDeviceProperties& getPhysDeviceProperties() {
+        assert( fGlobalShared != nullptr );
+        return fGlobalShared->physDeviceProperties;
+    }
+
 private:
     void initializeContext();
     void destroyContext();
+    static void checkDestroyShared();
 
     struct BackbufferInfo {
         uint32_t        fImageIndex;          // image this is associated with
@@ -64,11 +88,6 @@ private:
     void createBuffers(VkFormat format, SkColorType colorType, VkSharingMode);
     void destroyBuffers();
 
-    VkInstance fInstance = VK_NULL_HANDLE;
-    VkPhysicalDevice fPhysicalDevice = VK_NULL_HANDLE;
-    VkDevice fDevice = VK_NULL_HANDLE;
-    VkDebugReportCallbackEXT fDebugCallback = VK_NULL_HANDLE;
-
     // Create functions
     CreateVkSurfaceFn fCreateVkSurfaceFn;
     CanPresentFn      fCanPresentFn;
@@ -90,20 +109,44 @@ private:
     PFN_vkAcquireNextImageKHR fAcquireNextImageKHR = nullptr;
     PFN_vkQueuePresentKHR fQueuePresentKHR = nullptr;
 
-    PFN_vkDestroyInstance fDestroyInstance = nullptr;
     PFN_vkDeviceWaitIdle fDeviceWaitIdle = nullptr;
-    PFN_vkDestroyDebugReportCallbackEXT fDestroyDebugReportCallbackEXT = nullptr;
     PFN_vkQueueWaitIdle fQueueWaitIdle = nullptr;
-    PFN_vkDestroyDevice fDestroyDevice = nullptr;
     PFN_vkGetDeviceQueue fGetDeviceQueue = nullptr;
 
+    // We need to use just one GrContext, so share all the relevant data.
+    struct Shared : public SkRefCnt
+    {
+    PFN_vkDestroyInstance fDestroyInstance = nullptr;
+    PFN_vkDestroyDevice fDestroyDevice = nullptr;
+    PFN_vkDestroyDebugReportCallbackEXT fDestroyDebugReportCallbackEXT = nullptr;
+
+    VkInstance fInstance = VK_NULL_HANDLE;
+    VkPhysicalDevice fPhysicalDevice = VK_NULL_HANDLE;
+    VkDevice fDevice = VK_NULL_HANDLE;
+    VkDebugReportCallbackEXT fDebugCallback = VK_NULL_HANDLE;
+
     sk_sp<const GrVkInterface> fInterface;
 
-    VkSurfaceKHR      fSurface;
-    VkSwapchainKHR    fSwapchain;
+    // Original code had this as a function-local variable, but that seems wrong.
+    // It should exist as long as the context exists.
+    VkPhysicalDeviceFeatures2 features;
+
+    // Store this to make it accessible.
+    VkPhysicalDeviceProperties physDeviceProperties;
+
     uint32_t          fGraphicsQueueIndex;
     VkQueue           fGraphicsQueue;
     uint32_t          fPresentQueueIndex;
+
+    sk_sp<GrContext> fContext;
+    };
+
+    sk_sp<Shared> fShared;
+
+    static sk_sp<Shared> fGlobalShared;
+
+    VkSurfaceKHR      fSurface;
+    VkSwapchainKHR    fSwapchain;
     VkQueue           fPresentQueue;
 
     uint32_t               fImageCount;
diff --git a/tools/sk_app/unix/VulkanWindowContext_unix.cpp b/tools/sk_app/unix/VulkanWindowContext_unix.cpp
index 6f0ce0aceb..877578cede 100644
--- a/tools/sk_app/unix/VulkanWindowContext_unix.cpp
+++ b/tools/sk_app/unix/VulkanWindowContext_unix.cpp
@@ -30,7 +30,7 @@ std::unique_ptr<WindowContext> MakeVulkanForXlib(const XlibWindowInfo& info,
         return nullptr;
     }
 
-    auto createVkSurface = [&info, instProc](VkInstance instance) -> VkSurfaceKHR {
+    VulkanWindowContext::CreateVkSurfaceFn createVkSurface = [&info, instProc](VkInstance instance) -> VkSurfaceKHR {
         static PFN_vkCreateXcbSurfaceKHR createXcbSurfaceKHR = nullptr;
         if (!createXcbSurfaceKHR) {
             createXcbSurfaceKHR =
@@ -54,6 +54,9 @@ std::unique_ptr<WindowContext> MakeVulkanForXlib(const XlibWindowInfo& info,
 
         return surface;
     };
+    // Allow creating just the shared context, without an associated window.
+    if(info.fWindow == None)
+        createVkSurface = nullptr;
 
     auto canPresent = [&info, instProc](VkInstance instance, VkPhysicalDevice physDev,
                               uint32_t queueFamilyIndex) {
@@ -76,7 +79,7 @@ std::unique_ptr<WindowContext> MakeVulkanForXlib(const XlibWindowInfo& info,
     };
     std::unique_ptr<WindowContext> ctx(
             new VulkanWindowContext(displayParams, createVkSurface, canPresent, instProc, devProc));
-    if (!ctx->isValid()) {
+    if (!ctx->isValid() && createVkSurface != nullptr) {
         return nullptr;
     }
     return ctx;
diff --git a/tools/sk_app/win/VulkanWindowContext_win.cpp b/tools/sk_app/win/VulkanWindowContext_win.cpp
index 909c96127b..35e063ae28 100644
--- a/tools/sk_app/win/VulkanWindowContext_win.cpp
+++ b/tools/sk_app/win/VulkanWindowContext_win.cpp
@@ -30,7 +30,7 @@ std::unique_ptr<WindowContext> MakeVulkanForWin(HWND hwnd, const DisplayParams&
         return nullptr;
     }
 
-    auto createVkSurface = [hwnd, instProc] (VkInstance instance) -> VkSurfaceKHR {
+    VulkanWindowContext::CreateVkSurfaceFn createVkSurface = [hwnd, instProc] (VkInstance instance) -> VkSurfaceKHR {
         static PFN_vkCreateWin32SurfaceKHR createWin32SurfaceKHR = nullptr;
         if (!createWin32SurfaceKHR) {
             createWin32SurfaceKHR = (PFN_vkCreateWin32SurfaceKHR)
@@ -54,6 +54,9 @@ std::unique_ptr<WindowContext> MakeVulkanForWin(HWND hwnd, const DisplayParams&
 
         return surface;
     };
+    // Allow creating just the shared context, without an associated window.
+    if(hwnd == nullptr)
+        createVkSurface = nullptr;
 
     auto canPresent = [instProc] (VkInstance instance, VkPhysicalDevice physDev,
                                   uint32_t queueFamilyIndex) {
@@ -71,7 +74,7 @@ std::unique_ptr<WindowContext> MakeVulkanForWin(HWND hwnd, const DisplayParams&
 
     std::unique_ptr<WindowContext> ctx(
             new VulkanWindowContext(params, createVkSurface, canPresent, instProc, devProc));
-    if (!ctx->isValid()) {
+    if (!ctx->isValid() && createVkSurface != nullptr) {
         return nullptr;
     }
     return ctx;