1// dear imgui: Renderer Backend for Vulkan
2// This needs to be used along with a Platform Backend (e.g. GLFW, SDL, Win32, custom..)
3
4// Implemented features:
5// [x] Renderer: User texture binding. Use 'VkDescriptorSet' as ImTextureID. Read the FAQ about ImTextureID! See https://github.com/ocornut/imgui/pull/914 for discussions.
6// [X] Renderer: Large meshes support (64k+ vertices) with 16-bit indices.
7// [x] Renderer: Multi-viewport / platform windows. With issues (flickering when creating a new viewport).
8
9// Important: on 32-bit systems, user texture binding is only supported if your imconfig file has '#define ImTextureID ImU64'.
10// See imgui_impl_vulkan.cpp file for details.
11
12// The aim of imgui_impl_vulkan.h/.cpp is to be usable in your engine without any modification.
13// IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
14
15// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
16// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
17// Learn about Dear ImGui:
18// - FAQ https://dearimgui.com/faq
19// - Getting Started https://dearimgui.com/getting-started
20// - Documentation https://dearimgui.com/docs (same as your local docs/ folder).
21// - Introduction, links and more at the top of imgui.cpp
22
23// Important note to the reader who wish to integrate imgui_impl_vulkan.cpp/.h in their own engine/app.
24// - Common ImGui_ImplVulkan_XXX functions and structures are used to interface with imgui_impl_vulkan.cpp/.h.
25// You will use those if you want to use this rendering backend in your engine/app.
26// - Helper ImGui_ImplVulkanH_XXX functions and structures are only used by this example (main.cpp) and by
27// the backend itself (imgui_impl_vulkan.cpp), but should PROBABLY NOT be used by your own engine/app code.
28// Read comments in imgui_impl_vulkan.h.
29
30#pragma once
31#ifndef IMGUI_DISABLE
32#include "imgui.h" // IMGUI_IMPL_API
33
34// [Configuration] in order to use a custom Vulkan function loader:
35// (1) You'll need to disable default Vulkan function prototypes.
36// We provide a '#define IMGUI_IMPL_VULKAN_NO_PROTOTYPES' convenience configuration flag.
37// In order to make sure this is visible from the imgui_impl_vulkan.cpp compilation unit:
38// - Add '#define IMGUI_IMPL_VULKAN_NO_PROTOTYPES' in your imconfig.h file
39// - Or as a compilation flag in your build system
40// - Or uncomment here (not recommended because you'd be modifying imgui sources!)
41// - Do not simply add it in a .cpp file!
42// (2) Call ImGui_ImplVulkan_LoadFunctions() before ImGui_ImplVulkan_Init() with your custom function.
43// If you have no idea what this is, leave it alone!
44//#define IMGUI_IMPL_VULKAN_NO_PROTOTYPES
45
46// Vulkan includes
47#if defined(IMGUI_IMPL_VULKAN_NO_PROTOTYPES) && !defined(VK_NO_PROTOTYPES)
48#define VK_NO_PROTOTYPES
49#endif
50#if defined(VK_USE_PLATFORM_WIN32_KHR) && !defined(NOMINMAX)
51#define NOMINMAX
52#include <vulkan/vulkan.h>
53#else
54#include <vulkan/vulkan.h>
55#endif
56#if defined(VK_VERSION_1_3) || defined(VK_KHR_dynamic_rendering)
57#define IMGUI_IMPL_VULKAN_HAS_DYNAMIC_RENDERING
58#endif
59
60// Initialization data, for ImGui_ImplVulkan_Init()
61// - VkDescriptorPool should be created with VK_DESCRIPTOR_POOL_CREATE_FREE_DESCRIPTOR_SET_BIT,
62// and must contain a pool size large enough to hold an ImGui VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER descriptor.
63// - When using dynamic rendering, set UseDynamicRendering=true and fill PipelineRenderingCreateInfo structure.
64// [Please zero-clear before use!]
65struct ImGui_ImplVulkan_InitInfo
66{
67 VkInstance Instance;
68 VkPhysicalDevice PhysicalDevice;
69 VkDevice Device;
70 uint32_t QueueFamily;
71 VkQueue Queue;
72 VkDescriptorPool DescriptorPool; // See requirements in note above
73 VkRenderPass RenderPass; // Ignored if using dynamic rendering
74 uint32_t MinImageCount; // >= 2
75 uint32_t ImageCount; // >= MinImageCount
76 VkSampleCountFlagBits MSAASamples; // 0 defaults to VK_SAMPLE_COUNT_1_BIT
77
78 // (Optional)
79 VkPipelineCache PipelineCache;
80 uint32_t Subpass;
81
82 // (Optional) Dynamic Rendering
83 // Need to explicitly enable VK_KHR_dynamic_rendering extension to use this, even for Vulkan 1.3.
84 bool UseDynamicRendering;
85#ifdef IMGUI_IMPL_VULKAN_HAS_DYNAMIC_RENDERING
86 VkPipelineRenderingCreateInfoKHR PipelineRenderingCreateInfo;
87#endif
88
89 // (Optional) Allocation, Debugging
90 const VkAllocationCallbacks* Allocator;
91 void (*CheckVkResultFn)(VkResult err);
92 VkDeviceSize MinAllocationSize; // Minimum allocation size. Set to 1024*1024 to satisfy zealous best practices validation layer and waste a little memory.
93};
94
95// Called by user code
96IMGUI_IMPL_API bool ImGui_ImplVulkan_Init(ImGui_ImplVulkan_InitInfo* info);
97IMGUI_IMPL_API void ImGui_ImplVulkan_Shutdown();
98IMGUI_IMPL_API void ImGui_ImplVulkan_NewFrame();
99IMGUI_IMPL_API void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer command_buffer, VkPipeline pipeline = VK_NULL_HANDLE);
100IMGUI_IMPL_API bool ImGui_ImplVulkan_CreateFontsTexture();
101IMGUI_IMPL_API void ImGui_ImplVulkan_DestroyFontsTexture();
102IMGUI_IMPL_API void ImGui_ImplVulkan_SetMinImageCount(uint32_t min_image_count); // To override MinImageCount after initialization (e.g. if swap chain is recreated)
103
104// Register a texture (VkDescriptorSet == ImTextureID)
105// FIXME: This is experimental in the sense that we are unsure how to best design/tackle this problem
106// Please post to https://github.com/ocornut/imgui/pull/914 if you have suggestions.
107IMGUI_IMPL_API VkDescriptorSet ImGui_ImplVulkan_AddTexture(VkSampler sampler, VkImageView image_view, VkImageLayout image_layout);
108IMGUI_IMPL_API void ImGui_ImplVulkan_RemoveTexture(VkDescriptorSet descriptor_set);
109
110// Optional: load Vulkan functions with a custom function loader
111// This is only useful with IMGUI_IMPL_VULKAN_NO_PROTOTYPES / VK_NO_PROTOTYPES
112IMGUI_IMPL_API bool ImGui_ImplVulkan_LoadFunctions(PFN_vkVoidFunction(*loader_func)(const char* function_name, void* user_data), void* user_data = nullptr);
113
114//-------------------------------------------------------------------------
115// Internal / Miscellaneous Vulkan Helpers
116// (Used by example's main.cpp. Used by multi-viewport features. PROBABLY NOT used by your own engine/app.)
117//-------------------------------------------------------------------------
118// You probably do NOT need to use or care about those functions.
119// Those functions only exist because:
120// 1) they facilitate the readability and maintenance of the multiple main.cpp examples files.
121// 2) the multi-viewport / platform window implementation needs them internally.
122// Generally we avoid exposing any kind of superfluous high-level helpers in the bindings,
123// but it is too much code to duplicate everywhere so we exceptionally expose them.
124//
125// Your engine/app will likely _already_ have code to setup all that stuff (swap chain, render pass, frame buffers, etc.).
126// You may read this code to learn about Vulkan, but it is recommended you use you own custom tailored code to do equivalent work.
127// (The ImGui_ImplVulkanH_XXX functions do not interact with any of the state used by the regular ImGui_ImplVulkan_XXX functions)
128//-------------------------------------------------------------------------
129
130struct ImGui_ImplVulkanH_Frame;
131struct ImGui_ImplVulkanH_Window;
132
133// Helpers
134IMGUI_IMPL_API void ImGui_ImplVulkanH_CreateOrResizeWindow(VkInstance instance, VkPhysicalDevice physical_device, VkDevice device, ImGui_ImplVulkanH_Window* wnd, uint32_t queue_family, const VkAllocationCallbacks* allocator, int w, int h, uint32_t min_image_count);
135IMGUI_IMPL_API void ImGui_ImplVulkanH_DestroyWindow(VkInstance instance, VkDevice device, ImGui_ImplVulkanH_Window* wnd, const VkAllocationCallbacks* allocator);
136IMGUI_IMPL_API VkSurfaceFormatKHR ImGui_ImplVulkanH_SelectSurfaceFormat(VkPhysicalDevice physical_device, VkSurfaceKHR surface, const VkFormat* request_formats, int request_formats_count, VkColorSpaceKHR request_color_space);
137IMGUI_IMPL_API VkPresentModeKHR ImGui_ImplVulkanH_SelectPresentMode(VkPhysicalDevice physical_device, VkSurfaceKHR surface, const VkPresentModeKHR* request_modes, int request_modes_count);
138IMGUI_IMPL_API int ImGui_ImplVulkanH_GetMinImageCountFromPresentMode(VkPresentModeKHR present_mode);
139
140// Helper structure to hold the data needed by one rendering frame
141// (Used by example's main.cpp. Used by multi-viewport features. Probably NOT used by your own engine/app.)
142// [Please zero-clear before use!]
143struct ImGui_ImplVulkanH_Frame
144{
145 VkCommandPool CommandPool;
146 VkCommandBuffer CommandBuffer;
147 VkFence Fence;
148 VkImage Backbuffer;
149 VkImageView BackbufferView;
150 VkFramebuffer Framebuffer;
151};
152
153struct ImGui_ImplVulkanH_FrameSemaphores
154{
155 VkSemaphore ImageAcquiredSemaphore;
156 VkSemaphore RenderCompleteSemaphore;
157};
158
159// Helper structure to hold the data needed by one rendering context into one OS window
160// (Used by example's main.cpp. Used by multi-viewport features. Probably NOT used by your own engine/app.)
161struct ImGui_ImplVulkanH_Window
162{
163 int Width;
164 int Height;
165 VkSwapchainKHR Swapchain;
166 VkSurfaceKHR Surface;
167 VkSurfaceFormatKHR SurfaceFormat;
168 VkPresentModeKHR PresentMode;
169 VkRenderPass RenderPass;
170 VkPipeline Pipeline; // The window pipeline may uses a different VkRenderPass than the one passed in ImGui_ImplVulkan_InitInfo
171 bool UseDynamicRendering;
172 bool ClearEnable;
173 VkClearValue ClearValue;
174 uint32_t FrameIndex; // Current frame being rendered to (0 <= FrameIndex < FrameInFlightCount)
175 uint32_t ImageCount; // Number of simultaneous in-flight frames (returned by vkGetSwapchainImagesKHR, usually derived from min_image_count)
176 uint32_t SemaphoreCount; // Number of simultaneous in-flight frames + 1, to be able to use it in vkAcquireNextImageKHR
177 uint32_t SemaphoreIndex; // Current set of swapchain wait semaphores we're using (needs to be distinct from per frame data)
178 ImGui_ImplVulkanH_Frame* Frames;
179 ImGui_ImplVulkanH_FrameSemaphores* FrameSemaphores;
180
181 ImGui_ImplVulkanH_Window()
182 {
183 memset(s: (void*)this, c: 0, n: sizeof(*this));
184 PresentMode = (VkPresentModeKHR)~0; // Ensure we get an error if user doesn't set this.
185 ClearEnable = true;
186 }
187};
188
189#endif // #ifndef IMGUI_DISABLE
190

source code of imgui/backends/imgui_impl_vulkan.h