check for presentation queue

main.cpp

@@ -156,28 +156,51 @@ private:
       if (familyProperty.queueFlags & VK_QUEUE_GRAPHICS_BIT) {
         mGraphicsQueueFamilyIndex = index;
       }
+
+      VkBool32 presentationQueueSupport = false;
+      vkGetPhysicalDeviceSurfaceSupportKHR(mPhysicalDevice, index, mSurface, &presentationQueueSupport);
+
+      if (presentationQueueSupport) {
+        mPresentationQueueFamilyIndex = index;
+      }
+
       index++;
     }
 
-    if (index == -1) throw std::runtime_error("nu require queue families found");
+    if (mPresentationQueueFamilyIndex == -1 || mGraphicsQueueFamilyIndex == -1) {
+      throw std::runtime_error("nu require queue families found");
+    }
   }
 
   void createLogicalDevice() {
     float queuePriority = 1.f;
 
-    VkDeviceQueueCreateInfo queueCreateInfos {
+    VkDeviceQueueCreateInfo graphicsQueueCreateInfos {
       .sType = VK_STRUCTURE_TYPE_DEVICE_QUEUE_CREATE_INFO,
       .queueFamilyIndex = mGraphicsQueueFamilyIndex,
       .queueCount = 1,
       .pQueuePriorities = &queuePriority,
     };
 
+    VkDeviceQueueCreateInfo presentationQueueCreateInfos {
+        .sType = VK_STRUCTURE_TYPE_DEVICE_QUEUE_CREATE_INFO,
+        .queueFamilyIndex = mPresentationQueueFamilyIndex,
+        .queueCount = 1,
+        .pQueuePriorities = &queuePriority,
+    };
+
+    std::vector<VkDeviceQueueCreateInfo> queues = { graphicsQueueCreateInfos };
+
+    if (mPresentationQueueFamilyIndex != mGraphicsQueueFamilyIndex) {
+      queues.push_back(graphicsQueueCreateInfos);
+    }
+
     VkPhysicalDeviceFeatures features {};
 
     VkDeviceCreateInfo deviceCreateInfo {
       .sType = VK_STRUCTURE_TYPE_DEVICE_CREATE_INFO,
-      .queueCreateInfoCount = 1,
-      .pQueueCreateInfos = &queueCreateInfos,
+      .queueCreateInfoCount = (uint32_t) queues.size(),
+      .pQueueCreateInfos = queues.data(),
       .pEnabledFeatures = &features,
     };
 
@@ -188,6 +211,7 @@ private:
 
   void getQueues() {
     vkGetDeviceQueue(mDevice, mGraphicsQueueFamilyIndex, 0, &mGraphicsQueue);
+    vkGetDeviceQueue(mDevice, mPresentationQueueFamilyIndex, 0, &mPresentQueue);
   }
 
 
@@ -200,11 +224,15 @@ private:
 private:
   GLFWwindow* mWindow = nullptr;
 
+  uint32_t mGraphicsQueueFamilyIndex = -1;
+  uint32_t mPresentationQueueFamilyIndex = -1;
+
   VkInstance mInstance = VK_NULL_HANDLE;
   VkPhysicalDevice mPhysicalDevice = VK_NULL_HANDLE;
-  uint32_t mGraphicsQueueFamilyIndex = -1;
   VkDevice mDevice = VK_NULL_HANDLE;
+
   VkQueue mGraphicsQueue = VK_NULL_HANDLE;
+  VkQueue mPresentQueue = VK_NULL_HANDLE;
 
   VkSurfaceKHR mSurface = VK_NULL_HANDLE;
 };