From 46dc6966689379e7f1da523247a91cbe77f85e51 Mon Sep 17 00:00:00 2001
From: Warwick <warwick.l.e.new@gmail.com>
Date: Thu, 10 Oct 2024 17:39:16 +0100
Subject: [PATCH] enable validation layers

---
 src/main.c | 68 ++++++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 56 insertions(+), 12 deletions(-)

diff --git a/src/main.c b/src/main.c
index ba34ad5..6901559 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,4 +1,5 @@
 #include <stdbool.h>
+#include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -7,28 +8,67 @@
 #define GLFW_INCLUDE_VULKAN
 #include <GLFW/glfw3.h>
 
+#ifdef NDEBUG
+const bool enableValidationLayers = false;
+#else
+const bool enableValidationLayers = true;
+#endif
+
+const char *validationLayers[] = {"VK_LAYER_KHRONOS_validation"};
+size_t validationLayerCount =
+    sizeof(validationLayers) / sizeof(validationLayers[0]);
+
 typedef struct Application {
   GLFWwindow *window;
   VkInstance instance;
 } Application;
 
-bool verifyGlfwExtensionSupport(uint32_t extensionCount,
-                            VkExtensionProperties *extentions,
-                            uint32_t glfwExtensionCount,
-                            const char **glfwExtensions) {
-  uint32_t correctExtensions = 0;
-  for (uint32_t i = 0; i < glfwExtensionCount; i++) {
-    for (uint32_t j = 0; j < extensionCount; j++) {
-      if (strcmp(glfwExtensions[i], extentions[j].extensionName) == 0) {
-        correctExtensions++;
+bool checkValidationLayerSupport() {
+  uint32_t layerCount;
+  vkEnumerateInstanceLayerProperties(&layerCount, NULL);
+  VkLayerProperties availableLayers[layerCount];
+  vkEnumerateInstanceLayerProperties(&layerCount, availableLayers);
+
+  for (int i = 0; i < validationLayerCount; i++) {
+    bool layerFound = false;
+    for (int j = 0; j < layerCount; j++) {
+      if (strcmp(availableLayers[j].layerName, validationLayers[i]) == 0) {
+        layerFound = true;
         break;
       }
     }
+    if (!layerFound) {
+      return false;
+    }
   }
-  return correctExtensions == glfwExtensionCount;
+  return true;
+}
+
+bool verifyGlfwExtensionSupport(uint32_t extensionCount,
+                                VkExtensionProperties *extentions,
+                                uint32_t glfwExtensionCount,
+                                const char **glfwExtensions) {
+  for (uint32_t i = 0; i < glfwExtensionCount; i++) {
+    bool layerFound = false;
+    for (uint32_t j = 0; j < extensionCount; j++) {
+      if (strcmp(glfwExtensions[i], extentions[j].extensionName) == 0) {
+        layerFound = true;
+        break;
+      }
+    }
+    if (!layerFound) {
+      return false;
+    }
+  }
+  return true;
 }
 
 void createInstance(Application *app) {
+  if (enableValidationLayers && !checkValidationLayerSupport()) {
+    fprintf(stderr, "Validation layers requested, but not available!");
+    exit(EXIT_FAILURE);
+  }
+
   VkApplicationInfo appInfo = {
       .sType = VK_STRUCTURE_TYPE_APPLICATION_INFO,
       .pApplicationName = "Hello Triangle",
@@ -49,6 +89,10 @@ void createInstance(Application *app) {
       .ppEnabledExtensionNames = glfwExtensions,
       .enabledLayerCount = 0,
   };
+  if (enableValidationLayers) {
+    createInfo.enabledLayerCount = validationLayerCount;
+    createInfo.ppEnabledLayerNames = validationLayers;
+  }
 
   VkResult result = vkCreateInstance(&createInfo, NULL, &app->instance);
   if (result != VK_SUCCESS) {
@@ -61,8 +105,8 @@ void createInstance(Application *app) {
   VkExtensionProperties extensions[extensionCount];
   vkEnumerateInstanceExtensionProperties(NULL, &extensionCount, extensions);
 
-  if (!verifyGlfwExtensionSupport(extensionCount, extensions, glfwExtensionCount,
-                              glfwExtensions)) {
+  if (!verifyGlfwExtensionSupport(extensionCount, extensions,
+                                  glfwExtensionCount, glfwExtensions)) {
     fprintf(stderr, "Failed to find all required vulkan extentions for glfw\n");
     exit(EXIT_FAILURE);
   }