Handle creation of vulkan instance, update documentation

src/main.cpp

@@ -9,7 +9,7 @@
 class TriangleTestApplication {
   const uint32_t WIDTH = 800;
   const uint32_t HEIGHT = 600;
-  // Public facing function, Initializes our private functions and GLFW
+
 public:
   void run() {
     initWindow();
@@ -20,6 +20,8 @@ public:
 
 private:
   GLFWwindow *window;
+  VkInstance instance;
+
   // Initialize GLFW Window. First, Initialize GLFW lib, disable resizing for
   // now, and create window.
   void initWindow() {
@@ -30,15 +32,51 @@ private:
     // Settings for the window are set, create window reference.
     window = glfwCreateWindow(WIDTH, HEIGHT, "Vulkan", nullptr, nullptr);
   }
-  void initVulkan() {}
+ 
+  void initVulkan() {
+    // Set application info for the vulkan instance!
+	  VkApplicationInfo appInfo{};
+ 
+    appInfo.sType = VK_STRUCTURE_TYPE_APPLICATION_INFO;         // Tell vulkan that appInfo is a Application Info structure
+    appInfo.pApplicationName = "Triangle Test";                 // Give the struct a name to use
+    appInfo.applicationVersion = VK_MAKE_VERSION(1,0,0);        // Create a Major Minor Patch version number for the application!
+    appInfo.pEngineName = "No Engine";                          // Give an internal name for the engine running
+    appInfo.engineVersion = VK_MAKE_VERSION(1,0,0);             // Similar to the App version, give vulkan an *engine* version
+    appInfo.apiVersion = VK_API_VERSION_1_0;                    // Tell vulkan what the highest API version we will allow this program to run on
+  
+    VkInstanceCreateInfo createInfo{};                          // Define parameters of new vulkan instance
+    createInfo.sType = VK_STRUCTURE_TYPE_INSTANCE_CREATE_INFO;  // Tell vulkan this is a info structure 
+    createInfo.pApplicationInfo = &appInfo;                     // We just created a new appInfo structure, so we pass the pointer to it.
+    
+    // This gets a little weird, Vulkan is platform agnostic, so you need to figure out what extensions to interface with the current system are needed
+    // So, to figure out what extension codes and how many to use, feed the pointer into *glfwGetRequiredInstanceExtensions*, which will get the necessary extensions!
+    // From there, we can send that over to our createInfo Vulkan info struct to make it fully platform agnostic!
+    uint32_t glfwExtensionCount = 0;                            
+    const char** glfwExtensions;
+
+    glfwExtensions = glfwGetRequiredInstanceExtensions(&glfwExtensionCount);
+
+    createInfo.enabledExtensionCount = glfwExtensionCount;
+    createInfo.ppEnabledExtensionNames = glfwExtensions;
+
+    createInfo.enabledLayerCount = 0;
+    VkResult result = vkCreateInstance(&createInfo, nullptr, &instance);  // Finally create the Vulkan instance, passing in the info to create from, and the global instance to use!
+
+    if(result != VK_SUCCESS) {                                            // vkCreateInstance returns a VkResult, if its anything but success, we exit immediately. (VK_SUCCESS == 0)
+      throw std::runtime_error("Failed to create vulkan instance!");
+    }
+  }
+ 
   void mainLoop() {
     // Update window whilst open
     while (!glfwWindowShouldClose(window)) {
       glfwPollEvents();
     }
   }
+
   void cleanup() {
     // Cleanup window when destroyed.
+    vkDestroyInstance(instance, nullptr);
     glfwDestroyWindow(window);
     glfwTerminate();
   }