Added validation layer injection, working on message callbacks per the vulkan docs

Makefile

@@ -1,5 +1,6 @@
 CPPFLAGS=-g
 LDFLAGS=-lglfw -lvulkan -ldl -lpthread -lX11 -lXxf86vm -lXrandr -lXi
+DEBUGFLAGS=-DDEBUG
 SRC=$(shell find . -name *.cpp)
 OBJ=$(SRC:%.cpp=%.o)
 
@@ -12,6 +13,10 @@ all: $(BIN)
 .PHONY: run
 run: $(BIN)
 	./$(BIN)
+.PHONY: debug
+debug: LDFLAGS+=$(DEBUGFLAGS)
+debug: $(BIN)
+	./$(BIN)
 .PHONY: dep
 dep: 
 	sudo pacman -S gcc glfw glm shaderc libxi libxxf86vm

src/main.cpp

@@ -1,3 +1,6 @@
+#include <cstdint>
+#include <cstring>
+#include <vector>
 #define GLFW_INCLUDE_VULKAN
 #include <GLFW/glfw3.h>
 
@@ -10,6 +13,16 @@ class TriangleTestApplication {
   const uint32_t WIDTH = 800;
   const uint32_t HEIGHT = 600;
 
+  const std::vector<const char*> validationLayers = {
+    "VK_LAYER_KHRONOS_validation"
+  };
+
+  #ifdef DEBUG
+    const bool enableValidationLayers = true;
+  #else 
+    const bool enableValidationLayers = false;
+  #endif
+
 public:
   void run() {
     initWindow();
@@ -34,6 +47,14 @@ private:
   }
 
   void initVulkan() {
+    createInstance();
+  }
+
+  void createInstance() {
+    if(enableValidationLayers && !checkValidationLayerSupport()) {
+      throw std::runtime_error("Validation layers requested, but not available!");
+    }
+
     // Set application info for the vulkan instance!
 	  VkApplicationInfo appInfo{};
  
@@ -59,7 +80,12 @@ private:
     createInfo.enabledExtensionCount = glfwExtensionCount;
     createInfo.ppEnabledExtensionNames = glfwExtensions;
     
+    if(enableValidationLayers) {                                            // If we have validation layers, add them now, otherwise set it to 0
+      createInfo.enabledLayerCount = static_cast<uint32_t>(validationLayers.size());
+      createInfo.ppEnabledLayerNames = validationLayers.data();
+    } else {
       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)
@@ -67,6 +93,30 @@ private:
     }
   }
  
+  bool checkValidationLayerSupport() {                                      // This function is used to check Validation Layer Support, validation layers are the debug trace tools in the Vulkan SDK.
+    uint32_t layerCount;                                                    // layerCount will be used as the var to keep track of the number of requested validation layerk
+    vkEnumerateInstanceLayerProperties(&layerCount, nullptr);               // Set layerCount to the number of validation layers requested when pProperties is NULLPTR
+
+    std::vector<VkLayerProperties> availableLayers(layerCount);             // VkLayerProperties is a structure with data on the layername, desc, versions and etc. 
+    vkEnumerateInstanceLayerProperties(&layerCount, availableLayers.data());// Now that we have a VkLayerProperties fed in, as well as the num. of properties, we can fill layerCount with the VkResult
+
+    for(const char* layerName : validationLayers) {                         // Pretty straightforward from here, just enumerate over all the VkResult data and see if we have any validationLayers
+      bool layerFound = false;
+
+      for(const auto& layerProperties : availableLayers) {
+        if(strcmp(layerName, layerProperties.layerName) == 0) {
+          layerFound = true;
+          break;
+        }
+      }
+
+      if(!layerFound) {
+        return false;
+      }
+    }
+    return true;
+  }
+ 
   void mainLoop() {
     // Update window whilst open
     while (!glfwWindowShouldClose(window)) {
@@ -80,6 +130,7 @@ private:
     glfwDestroyWindow(window);
     glfwTerminate();
   }
+
 };
 
 int main() {