Backends: Vulkan: Added convenience support for Volk via IMGUI_IMPL_VULKAN_USE_VOLK define. (#6582, #4854)

backends/imgui_impl_vulkan.cpp

@@ -33,6 +33,7 @@
 
 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
+//  2024-04-19: Vulkan: Added convenience support for Volk via IMGUI_IMPL_VULKAN_USE_VOLK define (you can also use IMGUI_IMPL_VULKAN_NO_PROTOTYPES + wrap Volk via ImGui_ImplVulkan_LoadFunctions().)
 //  2024-02-14: *BREAKING CHANGE*: Moved RenderPass parameter from ImGui_ImplVulkan_Init() function to ImGui_ImplVulkan_InitInfo structure. Not required when using dynamic rendering.
 //  2024-02-12: *BREAKING CHANGE*: Dynamic rendering now require filling PipelineRenderingCreateInfo structure.
 //  2024-01-19: Vulkan: Fixed vkAcquireNextImageKHR() validation errors in VulkanSDK 1.3.275 by allocating one extra semaphore than in-flight frames. (#7236)
@@ -108,12 +109,13 @@ void ImGui_ImplVulkanH_CreateWindowCommandBuffers(VkPhysicalDevice physical_devi
 
 // Vulkan prototypes for use with custom loaders
 // (see description of IMGUI_IMPL_VULKAN_NO_PROTOTYPES in imgui_impl_vulkan.h
-#ifdef VK_NO_PROTOTYPES
+#if defined(VK_NO_PROTOTYPES) && !defined(VOLK_H_)
+#define IMGUI_IMPL_VULKAN_USE_LOADER
 static bool g_FunctionsLoaded = false;
 #else
 static bool g_FunctionsLoaded = true;
 #endif
-#ifdef VK_NO_PROTOTYPES
+#ifdef IMGUI_IMPL_VULKAN_USE_LOADER
 #define IMGUI_VULKAN_FUNC_MAP(IMGUI_VULKAN_FUNC_MAP_MACRO) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkAllocateCommandBuffers) \
     IMGUI_VULKAN_FUNC_MAP_MACRO(vkAllocateDescriptorSets) \
@@ -184,7 +186,7 @@ static bool g_FunctionsLoaded = true;
 #define IMGUI_VULKAN_FUNC_DEF(func) static PFN_##func func;
 IMGUI_VULKAN_FUNC_MAP(IMGUI_VULKAN_FUNC_DEF)
 #undef IMGUI_VULKAN_FUNC_DEF
-#endif // VK_NO_PROTOTYPES
+#endif // IMGUI_IMPL_VULKAN_USE_LOADER
 
 #ifdef IMGUI_IMPL_VULKAN_HAS_DYNAMIC_RENDERING
 static PFN_vkCmdBeginRenderingKHR   ImGuiImplVulkanFuncs_vkCmdBeginRenderingKHR;
@@ -1048,8 +1050,8 @@ bool    ImGui_ImplVulkan_LoadFunctions(PFN_vkVoidFunction(*loader_func)(const ch
     // Load function pointers
     // You can use the default Vulkan loader using:
     //      ImGui_ImplVulkan_LoadFunctions([](const char* function_name, void*) { return vkGetInstanceProcAddr(your_vk_isntance, function_name); });
-    // But this would be equivalent to not setting VK_NO_PROTOTYPES.
-#ifdef VK_NO_PROTOTYPES
+    // But this would be roughly equivalent to not setting VK_NO_PROTOTYPES.
+#ifdef IMGUI_IMPL_VULKAN_USE_LOADER
 #define IMGUI_VULKAN_FUNC_LOAD(func) \
     func = reinterpret_cast<decltype(func)>(loader_func(#func, user_data)); \
     if (func == nullptr)   \
@@ -1078,7 +1080,7 @@ bool    ImGui_ImplVulkan_Init(ImGui_ImplVulkan_InitInfo* info)
     if (info->UseDynamicRendering)
     {
 #ifdef IMGUI_IMPL_VULKAN_HAS_DYNAMIC_RENDERING
-#ifndef VK_NO_PROTOTYPES
+#ifndef IMGUI_IMPL_VULKAN_USE_LOADER
         ImGuiImplVulkanFuncs_vkCmdBeginRenderingKHR = reinterpret_cast<PFN_vkCmdBeginRenderingKHR>(vkGetInstanceProcAddr(info->Instance, "vkCmdBeginRenderingKHR"));
         ImGuiImplVulkanFuncs_vkCmdEndRenderingKHR = reinterpret_cast<PFN_vkCmdEndRenderingKHR>(vkGetInstanceProcAddr(info->Instance, "vkCmdEndRenderingKHR"));
 #endif

backends/imgui_impl_vulkan.h

@@ -42,13 +42,20 @@
 // If you have no idea what this is, leave it alone!
 //#define IMGUI_IMPL_VULKAN_NO_PROTOTYPES
 
-// Vulkan includes
+// Convenience support for Volk
+// (you can also technically use IMGUI_IMPL_VULKAN_NO_PROTOTYPES + wrap Volk via ImGui_ImplVulkan_LoadFunctions().)
+//#define IMGUI_IMPL_VULKAN_USE_VOLK
+
 #if defined(IMGUI_IMPL_VULKAN_NO_PROTOTYPES) && !defined(VK_NO_PROTOTYPES)
 #define VK_NO_PROTOTYPES
 #endif
 #if defined(VK_USE_PLATFORM_WIN32_KHR) && !defined(NOMINMAX)
 #define NOMINMAX
-#include <vulkan/vulkan.h>
+#endif
+
+// Vulkan includes
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+#include <Volk/volk.h>
 #else
 #include <vulkan/vulkan.h>
 #endif

docs/CHANGELOG.txt

@@ -66,8 +66,12 @@ Other changes:
   mitigitate issues with reading vertex indexing limits with 16-bit indices. (#7496, #5720)
 - Backends: OpenGL: Detect ES3 contexts on desktop based on version string,
   to e.g. avoid calling glPolygonMode() on them. (#7447) [@afraidofdark, @ocornut]
+- Backends: Vulkan: Added convenience support for Volk via IMGUI_IMPL_VULKAN_USE_VOLK define.
+  (you could always use IMGUI_IMPL_VULKAN_NO_PROTOTYPES + ImGui_ImplVulkan_LoadFunctions() as well).
+  (#6582, #4854) [@adalsteinnh, @kennyalive, @ocornut]
 - Backends: SDL3: Fixed text inputs. Re-enable calling SDL_StartTextInput()/SDL_StopTextInput()
   as SDL3 no longer enables it by default. (#7452, #6306, #6071, #1953) [@Green-Sky]
+- Examples: GLFW+Vulkan, SDL+Vulkan: Added optional support for Volk. (#6582, #4854)
 - Examples: GLFW+WebGPU: Added support for WebGPU-native/Dawn (#7435, #7132) [@eliasdaler, @Zelif]
 - Examples: GLFW+WebGPU: Renamed example_emscripten_wgpu/ to example_glfw_wgpu/. (#7435, #7132)
 

examples/example_glfw_vulkan/main.cpp

@@ -21,8 +21,12 @@
 #define GLFW_INCLUDE_NONE
 #define GLFW_INCLUDE_VULKAN
 #include <GLFW/glfw3.h>
-#include <vulkan/vulkan.h>
-//#include <vulkan/vulkan_beta.h>
+
+// Volk headers
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+#define VOLK_IMPLEMENTATION
+#include <Volk/volk.h>
+#endif
 
 // [Win32] Our example includes a copy of glfw3.lib pre-compiled with VS2010 to maximize ease of testing and compatibility with old VS compilers.
 // To link with VS2010-era libraries, VS2015+ requires linking with legacy_stdio_definitions.lib, which we do using this pragma.
@@ -113,6 +117,9 @@ static VkPhysicalDevice SetupVulkan_SelectPhysicalDevice()
 static void SetupVulkan(ImVector<const char*> instance_extensions)
 {
     VkResult err;
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+    volkInitialize();
+#endif
 
     // Create Vulkan Instance
     {
@@ -151,17 +158,20 @@ static void SetupVulkan(ImVector<const char*> instance_extensions)
         create_info.ppEnabledExtensionNames = instance_extensions.Data;
         err = vkCreateInstance(&create_info, g_Allocator, &g_Instance);
         check_vk_result(err);
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+        volkLoadInstance(g_Instance);
+#endif
 
         // Setup the debug report callback
 #ifdef APP_USE_VULKAN_DEBUG_REPORT
-        auto vkCreateDebugReportCallbackEXT = (PFN_vkCreateDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkCreateDebugReportCallbackEXT");
-        IM_ASSERT(vkCreateDebugReportCallbackEXT != nullptr);
+        auto f_vkCreateDebugReportCallbackEXT = (PFN_vkCreateDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkCreateDebugReportCallbackEXT");
+        IM_ASSERT(f_vkCreateDebugReportCallbackEXT != nullptr);
         VkDebugReportCallbackCreateInfoEXT debug_report_ci = {};
         debug_report_ci.sType = VK_STRUCTURE_TYPE_DEBUG_REPORT_CALLBACK_CREATE_INFO_EXT;
         debug_report_ci.flags = VK_DEBUG_REPORT_ERROR_BIT_EXT | VK_DEBUG_REPORT_WARNING_BIT_EXT | VK_DEBUG_REPORT_PERFORMANCE_WARNING_BIT_EXT;
         debug_report_ci.pfnCallback = debug_report;
         debug_report_ci.pUserData = nullptr;
-        err = vkCreateDebugReportCallbackEXT(g_Instance, &debug_report_ci, g_Allocator, &g_DebugReport);
+        err = f_vkCreateDebugReportCallbackEXT(g_Instance, &debug_report_ci, g_Allocator, &g_DebugReport);
         check_vk_result(err);
 #endif
     }
@@ -277,8 +287,8 @@ static void CleanupVulkan()
 
 #ifdef APP_USE_VULKAN_DEBUG_REPORT
     // Remove the debug report callback
-    auto vkDestroyDebugReportCallbackEXT = (PFN_vkDestroyDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkDestroyDebugReportCallbackEXT");
-    vkDestroyDebugReportCallbackEXT(g_Instance, g_DebugReport, g_Allocator);
+    auto f_vkDestroyDebugReportCallbackEXT = (PFN_vkDestroyDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkDestroyDebugReportCallbackEXT");
+    f_vkDestroyDebugReportCallbackEXT(g_Instance, g_DebugReport, g_Allocator);
 #endif // APP_USE_VULKAN_DEBUG_REPORT
 
     vkDestroyDevice(g_Device, g_Allocator);

examples/example_sdl2_vulkan/main.cpp

@@ -20,8 +20,12 @@
 #include <stdlib.h>         // abort
 #include <SDL.h>
 #include <SDL_vulkan.h>
-#include <vulkan/vulkan.h>
-//#include <vulkan/vulkan_beta.h>
+
+// Volk headers
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+#define VOLK_IMPLEMENTATION
+#include <Volk/volk.h>
+#endif
 
 //#define APP_USE_UNLIMITED_FRAME_RATE
 #ifdef _DEBUG
@@ -101,6 +105,9 @@ static VkPhysicalDevice SetupVulkan_SelectPhysicalDevice()
 static void SetupVulkan(ImVector<const char*> instance_extensions)
 {
     VkResult err;
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+    volkInitialize();
+#endif
 
     // Create Vulkan Instance
     {
@@ -139,17 +146,20 @@ static void SetupVulkan(ImVector<const char*> instance_extensions)
         create_info.ppEnabledExtensionNames = instance_extensions.Data;
         err = vkCreateInstance(&create_info, g_Allocator, &g_Instance);
         check_vk_result(err);
+#ifdef IMGUI_IMPL_VULKAN_USE_VOLK
+        volkLoadInstance(g_Instance);
+#endif
 
         // Setup the debug report callback
 #ifdef APP_USE_VULKAN_DEBUG_REPORT
-        auto vkCreateDebugReportCallbackEXT = (PFN_vkCreateDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkCreateDebugReportCallbackEXT");
-        IM_ASSERT(vkCreateDebugReportCallbackEXT != nullptr);
+        auto f_vkCreateDebugReportCallbackEXT = (PFN_vkCreateDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkCreateDebugReportCallbackEXT");
+        IM_ASSERT(f_vkCreateDebugReportCallbackEXT != nullptr);
         VkDebugReportCallbackCreateInfoEXT debug_report_ci = {};
         debug_report_ci.sType = VK_STRUCTURE_TYPE_DEBUG_REPORT_CALLBACK_CREATE_INFO_EXT;
         debug_report_ci.flags = VK_DEBUG_REPORT_ERROR_BIT_EXT | VK_DEBUG_REPORT_WARNING_BIT_EXT | VK_DEBUG_REPORT_PERFORMANCE_WARNING_BIT_EXT;
         debug_report_ci.pfnCallback = debug_report;
         debug_report_ci.pUserData = nullptr;
-        err = vkCreateDebugReportCallbackEXT(g_Instance, &debug_report_ci, g_Allocator, &g_DebugReport);
+        err = f_vkCreateDebugReportCallbackEXT(g_Instance, &debug_report_ci, g_Allocator, &g_DebugReport);
         check_vk_result(err);
 #endif
     }
@@ -265,8 +275,8 @@ static void CleanupVulkan()
 
 #ifdef APP_USE_VULKAN_DEBUG_REPORT
     // Remove the debug report callback
-    auto vkDestroyDebugReportCallbackEXT = (PFN_vkDestroyDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkDestroyDebugReportCallbackEXT");
-    vkDestroyDebugReportCallbackEXT(g_Instance, g_DebugReport, g_Allocator);
+    auto f_vkDestroyDebugReportCallbackEXT = (PFN_vkDestroyDebugReportCallbackEXT)vkGetInstanceProcAddr(g_Instance, "vkDestroyDebugReportCallbackEXT");
+    f_vkDestroyDebugReportCallbackEXT(g_Instance, g_DebugReport, g_Allocator);
 #endif // APP_USE_VULKAN_DEBUG_REPORT
 
     vkDestroyDevice(g_Device, g_Allocator);