text: #ifdef RHI_HAS_IMGUI 
  // dear imgui: Renderer for Vulkan
  // This needs to be used along with a Platform Binding (e.g. GLFW, SDL, Win32, custom..)
  
  // Missing features:
  //  [ ] Renderer: User texture binding. Changes of ImTextureID aren't supported by this binding! See https://github.com/ocornut/imgui/pull/914
  
  // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
  // If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.
  // https://github.com/ocornut/imgui
  
  // The aim of imgui_impl_vulkan.h/.cpp is to be usable in your engine without any modification.
  // IF YOU FEEL YOU NEED TO MAKE ANY CHANGE TO THIS CODE, please share them and your feedback at https://github.com/ocornut/imgui/
  
  // CHANGELOG
  // (minor and older changes stripped away, please see git history for details)
  //  2019-02-16: Vulkan: Viewport and clipping rectangles correctly using draw_data->FramebufferScale to allow retina display.
  //  2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
  //  2018-08-25: Vulkan: Fixed mishandled VkSurfaceCapabilitiesKHR::maxImageCount=0 case.
  //  2018-06-22: Inverted the parameters to ImGui_ImplVulkan_RenderDrawData() to be consistent with other bindings.
  //  2018-06-08: Misc: Extracted imgui_impl_vulkan.cpp/.h away from the old combined GLFW+Vulkan example.
  //  2018-06-08: Vulkan: Use draw_data->DisplayPos and draw_data->DisplaySize to setup projection matrix and clipping rectangle.
  //  2018-03-03: Vulkan: Various refactor, created a couple of ImGui_ImplVulkanH_XXX helper that the example can use and that viewport support will use.
  //  2018-03-01: Vulkan: Renamed ImGui_ImplVulkan_Init_Info to ImGui_ImplVulkan_InitInfo and fields to match more closely Vulkan terminology.
  //  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback, ImGui_ImplVulkan_Render() calls ImGui_ImplVulkan_RenderDrawData() itself.
  //  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
  //  2017-05-15: Vulkan: Fix scissor offset being negative. Fix new Vulkan validation warnings. Set required depth member for buffer image copy.
  //  2016-11-13: Vulkan: Fix validation layer warnings and errors and redeclare gl_PerVertex.
  //  2016-10-18: Vulkan: Add location decorators & change to use structs as in/out in glsl, update embedded spv (produced with glslangValidator -x). Null the released resources.
  //  2016-08-27: Vulkan: Fix Vulkan example for use when a depth buffer is active.
  
  #include "imgui.h"
  #include "imgui_impl_vulkan.h"
  #include <stdio.h>
  
  // Vulkan data
  static const VkAllocationCallbacks* g_Allocator = NULL;
  static VkPhysicalDevice             g_PhysicalDevice = VK_NULL_HANDLE;
  static VkInstance                   g_Instance = VK_NULL_HANDLE;
  static VkDevice                     g_Device = VK_NULL_HANDLE;
  static uint32_t                     g_QueueFamily = (uint32_t)-1;
  static VkQueue                      g_Queue = VK_NULL_HANDLE;
  static VkPipelineCache              g_PipelineCache = VK_NULL_HANDLE;
  static VkDescriptorPool             g_DescriptorPool = VK_NULL_HANDLE;
  static VkRenderPass                 g_RenderPass = VK_NULL_HANDLE;
  static void                         (*g_CheckVkResultFn)(VkResult err) = NULL;
  
  static VkDeviceSize                 g_BufferMemoryAlignment = 256;
  static VkPipelineCreateFlags        g_PipelineCreateFlags = 0;
  
  static VkDescriptorSetLayout        g_DescriptorSetLayout = VK_NULL_HANDLE;
  static VkPipelineLayout             g_PipelineLayout = VK_NULL_HANDLE;
  static VkDescriptorSet              g_DescriptorSet = VK_NULL_HANDLE;
  static VkPipeline                   g_Pipeline = VK_NULL_HANDLE;
  
  // Frame data
  struct FrameDataForRender
  {
      VkDeviceMemory  VertexBufferMemory;
      VkDeviceMemory  IndexBufferMemory;
      VkDeviceSize    VertexBufferSize;
      VkDeviceSize    IndexBufferSize;
      VkBuffer        VertexBuffer;
      VkBuffer        IndexBuffer;
  };
  static int                    g_FrameIndex = 0;
  static FrameDataForRender     g_FramesDataBuffers[IMGUI_VK_QUEUED_FRAMES] = {};
  
  // Font data
  static VkSampler              g_FontSampler = VK_NULL_HANDLE;
  static VkDeviceMemory         g_FontMemory = VK_NULL_HANDLE;
  static VkImage                g_FontImage = VK_NULL_HANDLE;
  static VkImageView            g_FontView = VK_NULL_HANDLE;
  static VkDeviceMemory         g_UploadBufferMemory = VK_NULL_HANDLE;
  static VkBuffer               g_UploadBuffer = VK_NULL_HANDLE;
  
  // glsl_shader.vert, compiled with:
  // # glslangValidator -V -x -o glsl_shader.vert.u32 glsl_shader.vert
  static uint32_t __glsl_shader_vert_spv[] =
  {
      0x07230203,0x00010000,0x00080001,0x0000002e,0x00000000,0x00020011,0x00000001,0x0006000b,
      0x00000001,0x4c534c47,0x6474732e,0x3035342e,0x00000000,0x0003000e,0x00000000,0x00000001,
      0x000a000f,0x00000000,0x00000004,0x6e69616d,0x00000000,0x0000000b,0x0000000f,0x00000015,
      0x0000001b,0x0000001c,0x00030003,0x00000002,0x000001c2,0x00040005,0x00000004,0x6e69616d,
      0x00000000,0x00030005,0x00000009,0x00000000,0x00050006,0x00000009,0x00000000,0x6f6c6f43,
      0x00000072,0x00040006,0x00000009,0x00000001,0x00005655,0x00030005,0x0000000b,0x0074754f,
      0x00040005,0x0000000f,0x6c6f4361,0x0000726f,0x00030005,0x00000015,0x00565561,0x00060005,
      0x00000019,0x505f6c67,0x65567265,0x78657472,0x00000000,0x00060006,0x00000019,0x00000000,
      0x505f6c67,0x7469736f,0x006e6f69,0x00030005,0x0000001b,0x00000000,0x00040005,0x0000001c,
      0x736f5061,0x00000000,0x00060005,0x0000001e,0x73755075,0x6e6f4368,0x6e617473,0x00000074,
      0x00050006,0x0000001e,0x00000000,0x61635375,0x0000656c,0x00060006,0x0000001e,0x00000001,
      0x61725475,0x616c736e,0x00006574,0x00030005,0x00000020,0x00006370,0x00040047,0x0000000b,
      0x0000001e,0x00000000,0x00040047,0x0000000f,0x0000001e,0x00000002,0x00040047,0x00000015,
      0x0000001e,0x00000001,0x00050048,0x00000019,0x00000000,0x0000000b,0x00000000,0x00030047,
      0x00000019,0x00000002,0x00040047,0x0000001c,0x0000001e,0x00000000,0x00050048,0x0000001e,
      0x00000000,0x00000023,0x00000000,0x00050048,0x0000001e,0x00000001,0x00000023,0x00000008,
      0x00030047,0x0000001e,0x00000002,0x00020013,0x00000002,0x00030021,0x00000003,0x00000002,
      0x00030016,0x00000006,0x00000020,0x00040017,0x00000007,0x00000006,0x00000004,0x00040017,
      0x00000008,0x00000006,0x00000002,0x0004001e,0x00000009,0x00000007,0x00000008,0x00040020,
      0x0000000a,0x00000003,0x00000009,0x0004003b,0x0000000a,0x0000000b,0x00000003,0x00040015,
      0x0000000c,0x00000020,0x00000001,0x0004002b,0x0000000c,0x0000000d,0x00000000,0x00040020,
      0x0000000e,0x00000001,0x00000007,0x0004003b,0x0000000e,0x0000000f,0x00000001,0x00040020,
      0x00000011,0x00000003,0x00000007,0x0004002b,0x0000000c,0x00000013,0x00000001,0x00040020,
      0x00000014,0x00000001,0x00000008,0x0004003b,0x00000014,0x00000015,0x00000001,0x00040020,
      0x00000017,0x00000003,0x00000008,0x0003001e,0x00000019,0x00000007,0x00040020,0x0000001a,
      0x00000003,0x00000019,0x0004003b,0x0000001a,0x0000001b,0x00000003,0x0004003b,0x00000014,
      0x0000001c,0x00000001,0x0004001e,0x0000001e,0x00000008,0x00000008,0x00040020,0x0000001f,
      0x00000009,0x0000001e,0x0004003b,0x0000001f,0x00000020,0x00000009,0x00040020,0x00000021,
      0x00000009,0x00000008,0x0004002b,0x00000006,0x00000028,0x00000000,0x0004002b,0x00000006,
      0x00000029,0x3f800000,0x00050036,0x00000002,0x00000004,0x00000000,0x00000003,0x000200f8,
      0x00000005,0x0004003d,0x00000007,0x00000010,0x0000000f,0x00050041,0x00000011,0x00000012,
      0x0000000b,0x0000000d,0x0003003e,0x00000012,0x00000010,0x0004003d,0x00000008,0x00000016,
      0x00000015,0x00050041,0x00000017,0x00000018,0x0000000b,0x00000013,0x0003003e,0x00000018,
      0x00000016,0x0004003d,0x00000008,0x0000001d,0x0000001c,0x00050041,0x00000021,0x00000022,
      0x00000020,0x0000000d,0x0004003d,0x00000008,0x00000023,0x00000022,0x00050085,0x00000008,
      0x00000024,0x0000001d,0x00000023,0x00050041,0x00000021,0x00000025,0x00000020,0x00000013,
      0x0004003d,0x00000008,0x00000026,0x00000025,0x00050081,0x00000008,0x00000027,0x00000024,
      0x00000026,0x00050051,0x00000006,0x0000002a,0x00000027,0x00000000,0x00050051,0x00000006,
      0x0000002b,0x00000027,0x00000001,0x00070050,0x00000007,0x0000002c,0x0000002a,0x0000002b,
      0x00000028,0x00000029,0x00050041,0x00000011,0x0000002d,0x0000001b,0x0000000d,0x0003003e,
      0x0000002d,0x0000002c,0x000100fd,0x00010038
  };
  
  // glsl_shader.frag, compiled with:
  // # glslangValidator -V -x -o glsl_shader.frag.u32 glsl_shader.frag
  static uint32_t __glsl_shader_frag_spv[] =
  {
      0x07230203,0x00010000,0x00080001,0x0000001e,0x00000000,0x00020011,0x00000001,0x0006000b,
      0x00000001,0x4c534c47,0x6474732e,0x3035342e,0x00000000,0x0003000e,0x00000000,0x00000001,
      0x0007000f,0x00000004,0x00000004,0x6e69616d,0x00000000,0x00000009,0x0000000d,0x00030010,
      0x00000004,0x00000007,0x00030003,0x00000002,0x000001c2,0x00040005,0x00000004,0x6e69616d,
      0x00000000,0x00040005,0x00000009,0x6c6f4366,0x0000726f,0x00030005,0x0000000b,0x00000000,
      0x00050006,0x0000000b,0x00000000,0x6f6c6f43,0x00000072,0x00040006,0x0000000b,0x00000001,
      0x00005655,0x00030005,0x0000000d,0x00006e49,0x00050005,0x00000016,0x78655473,0x65727574,
      0x00000000,0x00040047,0x00000009,0x0000001e,0x00000000,0x00040047,0x0000000d,0x0000001e,
      0x00000000,0x00040047,0x00000016,0x00000022,0x00000000,0x00040047,0x00000016,0x00000021,
      0x00000000,0x00020013,0x00000002,0x00030021,0x00000003,0x00000002,0x00030016,0x00000006,
      0x00000020,0x00040017,0x00000007,0x00000006,0x00000004,0x00040020,0x00000008,0x00000003,
      0x00000007,0x0004003b,0x00000008,0x00000009,0x00000003,0x00040017,0x0000000a,0x00000006,
      0x00000002,0x0004001e,0x0000000b,0x00000007,0x0000000a,0x00040020,0x0000000c,0x00000001,
      0x0000000b,0x0004003b,0x0000000c,0x0000000d,0x00000001,0x00040015,0x0000000e,0x00000020,
      0x00000001,0x0004002b,0x0000000e,0x0000000f,0x00000000,0x00040020,0x00000010,0x00000001,
      0x00000007,0x00090019,0x00000013,0x00000006,0x00000001,0x00000000,0x00000000,0x00000000,
      0x00000001,0x00000000,0x0003001b,0x00000014,0x00000013,0x00040020,0x00000015,0x00000000,
      0x00000014,0x0004003b,0x00000015,0x00000016,0x00000000,0x0004002b,0x0000000e,0x00000018,
      0x00000001,0x00040020,0x00000019,0x00000001,0x0000000a,0x00050036,0x00000002,0x00000004,
      0x00000000,0x00000003,0x000200f8,0x00000005,0x00050041,0x00000010,0x00000011,0x0000000d,
      0x0000000f,0x0004003d,0x00000007,0x00000012,0x00000011,0x0004003d,0x00000014,0x00000017,
      0x00000016,0x00050041,0x00000019,0x0000001a,0x0000000d,0x00000018,0x0004003d,0x0000000a,
      0x0000001b,0x0000001a,0x00050057,0x00000007,0x0000001c,0x00000017,0x0000001b,0x00050085,
      0x00000007,0x0000001d,0x00000012,0x0000001c,0x0003003e,0x00000009,0x0000001d,0x000100fd,
      0x00010038
  };
  
  static uint32_t ImGui_ImplVulkan_MemoryType(VkMemoryPropertyFlags properties, uint32_t type_bits)
  {
      VkPhysicalDeviceMemoryProperties prop;
      vkGetPhysicalDeviceMemoryProperties(g_PhysicalDevice, &prop);
      for (uint32_t i = 0; i < prop.memoryTypeCount; i++)
          if ((prop.memoryTypes[i].propertyFlags & properties) == properties && type_bits & (1<<i))
              return i;
      return 0xFFFFFFFF; // Unable to find memoryType
  }
  
  static void check_vk_result(VkResult err)
  {
      if (g_CheckVkResultFn)
          g_CheckVkResultFn(err);
  }
  
  static void CreateOrResizeBuffer(VkBuffer& buffer, VkDeviceMemory& buffer_memory, VkDeviceSize& p_buffer_size, size_t new_size, VkBufferUsageFlagBits usage)
  {
      VkResult err;
      if (buffer != VK_NULL_HANDLE)
          vkDestroyBuffer(g_Device, buffer, g_Allocator);
      if (buffer_memory)
          vkFreeMemory(g_Device, buffer_memory, g_Allocator);
  
      VkDeviceSize vertex_buffer_size_aligned = ((new_size - 1) / g_BufferMemoryAlignment + 1) * g_BufferMemoryAlignment;
      VkBufferCreateInfo buffer_info = {};
      buffer_info.sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
      buffer_info.size = vertex_buffer_size_aligned;
      buffer_info.usage = usage;
      buffer_info.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
      err = vkCreateBuffer(g_Device, &buffer_info, g_Allocator, &buffer);
      check_vk_result(err);
  
      VkMemoryRequirements req;
      vkGetBufferMemoryRequirements(g_Device, buffer, &req);
      g_BufferMemoryAlignment = (g_BufferMemoryAlignment > req.alignment) ? g_BufferMemoryAlignment : req.alignment;
      VkMemoryAllocateInfo alloc_info = {};
      alloc_info.sType = VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO;
      alloc_info.allocationSize = req.size;
      alloc_info.memoryTypeIndex = ImGui_ImplVulkan_MemoryType(VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT, req.memoryTypeBits);
      err = vkAllocateMemory(g_Device, &alloc_info, g_Allocator, &buffer_memory);
      check_vk_result(err);
  
      err = vkBindBufferMemory(g_Device, buffer, buffer_memory, 0);
      check_vk_result(err);
      p_buffer_size = new_size;
  }
  
  // Render function
  // (this used to be set in io.RenderDrawListsFn and called by ImGui::Render(), but you can now call this directly from your main loop)
  void ImGui_ImplVulkan_RenderDrawData(ImDrawData* draw_data, VkCommandBuffer command_buffer)
  {
      // Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
      int fb_width = (int)(draw_data->DisplaySize.x * draw_data->FramebufferScale.x);
      int fb_height = (int)(draw_data->DisplaySize.y * draw_data->FramebufferScale.y);
      if (fb_width <= 0 || fb_height <= 0 || draw_data->TotalVtxCount == 0)
          return;
  
      VkResult err;
      FrameDataForRender* fd = &g_FramesDataBuffers[g_FrameIndex];
      g_FrameIndex = (g_FrameIndex + 1) % IMGUI_VK_QUEUED_FRAMES;
  
      // Create the Vertex and Index buffers:
      size_t vertex_size = draw_data->TotalVtxCount * sizeof(ImDrawVert);
      size_t index_size = draw_data->TotalIdxCount * sizeof(ImDrawIdx);
      if (!fd->VertexBuffer || fd->VertexBufferSize < vertex_size)
          CreateOrResizeBuffer(fd->VertexBuffer, fd->VertexBufferMemory, fd->VertexBufferSize, vertex_size, VK_BUFFER_USAGE_VERTEX_BUFFER_BIT);
      if (!fd->IndexBuffer || fd->IndexBufferSize < index_size)
          CreateOrResizeBuffer(fd->IndexBuffer, fd->IndexBufferMemory, fd->IndexBufferSize, index_size, VK_BUFFER_USAGE_INDEX_BUFFER_BIT);
  
      // Upload Vertex and index Data:
      {
          ImDrawVert* vtx_dst = NULL;
          ImDrawIdx* idx_dst = NULL;
          err = vkMapMemory(g_Device, fd->VertexBufferMemory, 0, vertex_size, 0, (void**)(&vtx_dst));
          check_vk_result(err);
          err = vkMapMemory(g_Device, fd->IndexBufferMemory, 0, index_size, 0, (void**)(&idx_dst));
          check_vk_result(err);
          for (int n = 0; n < draw_data->CmdListsCount; n++)
          {
              const ImDrawList* cmd_list = draw_data->CmdLists[n];
              memcpy(vtx_dst, cmd_list->VtxBuffer.Data, cmd_list->VtxBuffer.Size * sizeof(ImDrawVert));
              memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
              vtx_dst += cmd_list->VtxBuffer.Size;
              idx_dst += cmd_list->IdxBuffer.Size;
          }
          VkMappedMemoryRange range[2] = {};
          range[0].sType = VK_STRUCTURE_TYPE_MAPPED_MEMORY_RANGE;
          range[0].memory = fd->VertexBufferMemory;
          range[0].size = VK_WHOLE_SIZE;
          range[1].sType = VK_STRUCTURE_TYPE_MAPPED_MEMORY_RANGE;
          range[1].memory = fd->IndexBufferMemory;
          range[1].size = VK_WHOLE_SIZE;
          err = vkFlushMappedMemoryRanges(g_Device, 2, range);
          check_vk_result(err);
          vkUnmapMemory(g_Device, fd->VertexBufferMemory);
          vkUnmapMemory(g_Device, fd->IndexBufferMemory);
      }
  
      // Bind pipeline and descriptor sets:
      {
          vkCmdBindPipeline(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, g_Pipeline);
          VkDescriptorSet desc_set[1] = { g_DescriptorSet };
          vkCmdBindDescriptorSets(command_buffer, VK_PIPELINE_BIND_POINT_GRAPHICS, g_PipelineLayout, 0, 1, desc_set, 0, NULL);
      }
  
      // Bind Vertex And Index Buffer:
      {
          VkBuffer vertex_buffers[1] = { fd->VertexBuffer };
          VkDeviceSize vertex_offset[1] = { 0 };
          vkCmdBindVertexBuffers(command_buffer, 0, 1, vertex_buffers, vertex_offset);
          vkCmdBindIndexBuffer(command_buffer, fd->IndexBuffer, 0, VK_INDEX_TYPE_UINT16);
      }
  
      // Setup viewport:
      {
          VkViewport viewport;
          viewport.x = 0;
          viewport.y = 0;
          viewport.width = (float)fb_width;
          viewport.height = (float)fb_height;
          viewport.minDepth = 0.0f;
          viewport.maxDepth = 1.0f;
          vkCmdSetViewport(command_buffer, 0, 1, &viewport);
      }
  
      // Setup scale and translation:
      // Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayMin is typically (0,0) for single viewport apps.
      {
          float scale[2];
          scale[0] = 2.0f / draw_data->DisplaySize.x;
          scale[1] = 2.0f / draw_data->DisplaySize.y;
          float translate[2];
          translate[0] = -1.0f - draw_data->DisplayPos.x * scale[0];
          translate[1] = -1.0f - draw_data->DisplayPos.y * scale[1];
          vkCmdPushConstants(command_buffer, g_PipelineLayout, VK_SHADER_STAGE_VERTEX_BIT, sizeof(float) * 0, sizeof(float) * 2, scale);
          vkCmdPushConstants(command_buffer, g_PipelineLayout, VK_SHADER_STAGE_VERTEX_BIT, sizeof(float) * 2, sizeof(float) * 2, translate);
      }
  
      // Will project scissor/clipping rectangles into framebuffer space
      ImVec2 clip_off = draw_data->DisplayPos;         // (0,0) unless using multi-viewports
      ImVec2 clip_scale = draw_data->FramebufferScale; // (1,1) unless using retina display which are often (2,2)
  
      // Render command lists
      int vtx_offset = 0;
      int idx_offset = 0;
      for (int n = 0; n < draw_data->CmdListsCount; n++)
      {
          const ImDrawList* cmd_list = draw_data->CmdLists[n];
          for (int cmd_i = 0; cmd_i < cmd_list->CmdBuffer.Size; cmd_i++)
          {
              const ImDrawCmd* pcmd = &cmd_list->CmdBuffer[cmd_i];
              if (pcmd->UserCallback)
              {
                  pcmd->UserCallback(cmd_list, pcmd);
              }
              else
              {
                  // Project scissor/clipping rectangles into framebuffer space
                  ImVec4 clip_rect;
                  clip_rect.x = (pcmd->ClipRect.x - clip_off.x) * clip_scale.x;
                  clip_rect.y = (pcmd->ClipRect.y - clip_off.y) * clip_scale.y;
                  clip_rect.z = (pcmd->ClipRect.z - clip_off.x) * clip_scale.x;
                  clip_rect.w = (pcmd->ClipRect.w - clip_off.y) * clip_scale.y;
  
                  if (clip_rect.x < fb_width && clip_rect.y < fb_height && clip_rect.z >= 0.0f && clip_rect.w >= 0.0f)
                  {
                      // Apply scissor/clipping rectangle
                      VkRect2D scissor;
                      scissor.offset.x = (int32_t)(clip_rect.x);
                      scissor.offset.y = (int32_t)(clip_rect.y);
                      scissor.extent.width = (uint32_t)(clip_rect.z - clip_rect.x);
                      scissor.extent.height = (uint32_t)(clip_rect.w - clip_rect.y);
                      vkCmdSetScissor(command_buffer, 0, 1, &scissor);
  
                      // Draw
                      vkCmdDrawIndexed(command_buffer, pcmd->ElemCount, 1, idx_offset, vtx_offset, 0);
                  }
              }
              idx_offset += pcmd->ElemCount;
          }
          vtx_offset += cmd_list->VtxBuffer.Size;
      }
  }
  
  bool ImGui_ImplVulkan_CreateFontsTexture(VkCommandBuffer command_buffer)
  {
      ImGuiIO& io = ImGui::GetIO();
  
      unsigned char* pixels;
      int width, height;
      io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);
      size_t upload_size = sizeof(char) * width * height * 4;
  
      VkResult err;
  
      // Create the Image:
      {
          VkImageCreateInfo info = {};
          info.sType = VK_STRUCTURE_TYPE_IMAGE_CREATE_INFO;
          info.imageType = VK_IMAGE_TYPE_2D;
          info.format = VK_FORMAT_R8G8B8A8_UNORM;
          info.extent.width = width;
          info.extent.height = height;
          info.extent.depth = 1;
          info.mipLevels = 1;
          info.arrayLayers = 1;
          info.samples = VK_SAMPLE_COUNT_1_BIT;
          info.tiling = VK_IMAGE_TILING_OPTIMAL;
          info.usage = VK_IMAGE_USAGE_SAMPLED_BIT | VK_IMAGE_USAGE_TRANSFER_DST_BIT;
          info.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
          info.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
          err = vkCreateImage(g_Device, &info, g_Allocator, &g_FontImage);
          check_vk_result(err);
          VkMemoryRequirements req;
          vkGetImageMemoryRequirements(g_Device, g_FontImage, &req);
          VkMemoryAllocateInfo alloc_info = {};
          alloc_info.sType = VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO;
          alloc_info.allocationSize = req.size;
          alloc_info.memoryTypeIndex = ImGui_ImplVulkan_MemoryType(VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, req.memoryTypeBits);
          err = vkAllocateMemory(g_Device, &alloc_info, g_Allocator, &g_FontMemory);
          check_vk_result(err);
          err = vkBindImageMemory(g_Device, g_FontImage, g_FontMemory, 0);
          check_vk_result(err);
      }
  
      // Create the Image View:
      {
          VkImageViewCreateInfo info = {};
          info.sType = VK_STRUCTURE_TYPE_IMAGE_VIEW_CREATE_INFO;
          info.image = g_FontImage;
          info.viewType = VK_IMAGE_VIEW_TYPE_2D;
          info.format = VK_FORMAT_R8G8B8A8_UNORM;
          info.subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
          info.subresourceRange.levelCount = 1;
          info.subresourceRange.layerCount = 1;
          err = vkCreateImageView(g_Device, &info, g_Allocator, &g_FontView);
          check_vk_result(err);
      }
  
      // Update the Descriptor Set:
      {
          VkDescriptorImageInfo desc_image[1] = {};
          desc_image[0].sampler = g_FontSampler;
          desc_image[0].imageView = g_FontView;
          desc_image[0].imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
          VkWriteDescriptorSet write_desc[1] = {};
          write_desc[0].sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET;
          write_desc[0].dstSet = g_DescriptorSet;
          write_desc[0].descriptorCount = 1;
          write_desc[0].descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER;
          write_desc[0].pImageInfo = desc_image;
          vkUpdateDescriptorSets(g_Device, 1, write_desc, 0, NULL);
      }
  
      // Create the Upload Buffer:
      {
          VkBufferCreateInfo buffer_info = {};
          buffer_info.sType = VK_STRUCTURE_TYPE_BUFFER_CREATE_INFO;
          buffer_info.size = upload_size;
          buffer_info.usage = VK_BUFFER_USAGE_TRANSFER_SRC_BIT;
          buffer_info.sharingMode = VK_SHARING_MODE_EXCLUSIVE;
          err = vkCreateBuffer(g_Device, &buffer_info, g_Allocator, &g_UploadBuffer);
          check_vk_result(err);
          VkMemoryRequirements req;
          vkGetBufferMemoryRequirements(g_Device, g_UploadBuffer, &req);
          g_BufferMemoryAlignment = (g_BufferMemoryAlignment > req.alignment) ? g_BufferMemoryAlignment : req.alignment;
          VkMemoryAllocateInfo alloc_info = {};
          alloc_info.sType = VK_STRUCTURE_TYPE_MEMORY_ALLOCATE_INFO;
          alloc_info.allocationSize = req.size;
          alloc_info.memoryTypeIndex = ImGui_ImplVulkan_MemoryType(VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT, req.memoryTypeBits);
          err = vkAllocateMemory(g_Device, &alloc_info, g_Allocator, &g_UploadBufferMemory);
          check_vk_result(err);
          err = vkBindBufferMemory(g_Device, g_UploadBuffer, g_UploadBufferMemory, 0);
          check_vk_result(err);
      }
  
      // Upload to Buffer:
      {
          char* map = NULL;
          err = vkMapMemory(g_Device, g_UploadBufferMemory, 0, upload_size, 0, (void**)(&map));
          check_vk_result(err);
          memcpy(map, pixels, upload_size);
          VkMappedMemoryRange range[1] = {};
          range[0].sType = VK_STRUCTURE_TYPE_MAPPED_MEMORY_RANGE;
          range[0].memory = g_UploadBufferMemory;
          range[0].size = upload_size;
          err = vkFlushMappedMemoryRanges(g_Device, 1, range);
          check_vk_result(err);
          vkUnmapMemory(g_Device, g_UploadBufferMemory);
      }
  
      // Copy to Image:
      {
          VkImageMemoryBarrier copy_barrier[1] = {};
          copy_barrier[0].sType = VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER;
          copy_barrier[0].dstAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
          copy_barrier[0].oldLayout = VK_IMAGE_LAYOUT_UNDEFINED;
          copy_barrier[0].newLayout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
          copy_barrier[0].srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
          copy_barrier[0].dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
          copy_barrier[0].image = g_FontImage;
          copy_barrier[0].subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
          copy_barrier[0].subresourceRange.levelCount = 1;
          copy_barrier[0].subresourceRange.layerCount = 1;
          vkCmdPipelineBarrier(command_buffer, VK_PIPELINE_STAGE_HOST_BIT, VK_PIPELINE_STAGE_TRANSFER_BIT, 0, 0, NULL, 0, NULL, 1, copy_barrier);
  
          VkBufferImageCopy region = {};
          region.imageSubresource.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
          region.imageSubresource.layerCount = 1;
          region.imageExtent.width = width;
          region.imageExtent.height = height;
          region.imageExtent.depth = 1;
          vkCmdCopyBufferToImage(command_buffer, g_UploadBuffer, g_FontImage, VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL, 1, &region);
  
          VkImageMemoryBarrier use_barrier[1] = {};
          use_barrier[0].sType = VK_STRUCTURE_TYPE_IMAGE_MEMORY_BARRIER;
          use_barrier[0].srcAccessMask = VK_ACCESS_TRANSFER_WRITE_BIT;
          use_barrier[0].dstAccessMask = VK_ACCESS_SHADER_READ_BIT;
          use_barrier[0].oldLayout = VK_IMAGE_LAYOUT_TRANSFER_DST_OPTIMAL;
          use_barrier[0].newLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
          use_barrier[0].srcQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
          use_barrier[0].dstQueueFamilyIndex = VK_QUEUE_FAMILY_IGNORED;
          use_barrier[0].image = g_FontImage;
          use_barrier[0].subresourceRange.aspectMask = VK_IMAGE_ASPECT_COLOR_BIT;
          use_barrier[0].subresourceRange.levelCount = 1;
          use_barrier[0].subresourceRange.layerCount = 1;
          vkCmdPipelineBarrier(command_buffer, VK_PIPELINE_STAGE_TRANSFER_BIT, VK_PIPELINE_STAGE_FRAGMENT_SHADER_BIT, 0, 0, NULL, 0, NULL, 1, use_barrier);
      }
  
      // Store our identifier
      io.Fonts->TexID = (ImTextureID)(intptr_t)g_FontImage;
  
      return true;
  }
  
  bool ImGui_ImplVulkan_CreateDeviceObjects()
  {
      VkResult err;
      VkShaderModule vert_module;
      VkShaderModule frag_module;
  
      // Create The Shader Modules:
      {
          VkShaderModuleCreateInfo vert_info = {};
          vert_info.sType = VK_STRUCTURE_TYPE_SHADER_MODULE_CREATE_INFO;
          vert_info.codeSize = sizeof(__glsl_shader_vert_spv);
          vert_info.pCode = (uint32_t*)__glsl_shader_vert_spv;
          err = vkCreateShaderModule(g_Device, &vert_info, g_Allocator, &vert_module);
          check_vk_result(err);
          VkShaderModuleCreateInfo frag_info = {};
          frag_info.sType = VK_STRUCTURE_TYPE_SHADER_MODULE_CREATE_INFO;
          frag_info.codeSize = sizeof(__glsl_shader_frag_spv);
          frag_info.pCode = (uint32_t*)__glsl_shader_frag_spv;
          err = vkCreateShaderModule(g_Device, &frag_info, g_Allocator, &frag_module);
          check_vk_result(err);
      }
  
      if (!g_FontSampler)
      {
          VkSamplerCreateInfo info = {};
          info.sType = VK_STRUCTURE_TYPE_SAMPLER_CREATE_INFO;
          info.magFilter = VK_FILTER_LINEAR;
          info.minFilter = VK_FILTER_LINEAR;
          info.mipmapMode = VK_SAMPLER_MIPMAP_MODE_LINEAR;
          info.addressModeU = VK_SAMPLER_ADDRESS_MODE_REPEAT;
          info.addressModeV = VK_SAMPLER_ADDRESS_MODE_REPEAT;
          info.addressModeW = VK_SAMPLER_ADDRESS_MODE_REPEAT;
          info.minLod = -1000;
          info.maxLod = 1000;
          info.maxAnisotropy = 1.0f;
          err = vkCreateSampler(g_Device, &info, g_Allocator, &g_FontSampler);
          check_vk_result(err);
      }
  
      if (!g_DescriptorSetLayout)
      {
          VkSampler sampler[1] = {g_FontSampler};
          VkDescriptorSetLayoutBinding binding[1] = {};
          binding[0].descriptorType = VK_DESCRIPTOR_TYPE_COMBINED_IMAGE_SAMPLER;
          binding[0].descriptorCount = 1;
          binding[0].stageFlags = VK_SHADER_STAGE_FRAGMENT_BIT;
          binding[0].pImmutableSamplers = sampler;
          VkDescriptorSetLayoutCreateInfo info = {};
          info.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_LAYOUT_CREATE_INFO;
          info.bindingCount = 1;
          info.pBindings = binding;
          err = vkCreateDescriptorSetLayout(g_Device, &info, g_Allocator, &g_DescriptorSetLayout);
          check_vk_result(err);
      }
  
      // Create Descriptor Set:
      {
          VkDescriptorSetAllocateInfo alloc_info = {};
          alloc_info.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_ALLOCATE_INFO;
          alloc_info.descriptorPool = g_DescriptorPool;
          alloc_info.descriptorSetCount = 1;
          alloc_info.pSetLayouts = &g_DescriptorSetLayout;
          err = vkAllocateDescriptorSets(g_Device, &alloc_info, &g_DescriptorSet);
          check_vk_result(err);
      }
  
      if (!g_PipelineLayout)
      {
          // Constants: we are using 'vec2 offset' and 'vec2 scale' instead of a full 3d projection matrix
          VkPushConstantRange push_constants[1] = {};
          push_constants[0].stageFlags = VK_SHADER_STAGE_VERTEX_BIT;
          push_constants[0].offset = sizeof(float) * 0;
          push_constants[0].size = sizeof(float) * 4;
          VkDescriptorSetLayout set_layout[1] = { g_DescriptorSetLayout };
          VkPipelineLayoutCreateInfo layout_info = {};
          layout_info.sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO;
          layout_info.setLayoutCount = 1;
          layout_info.pSetLayouts = set_layout;
          layout_info.pushConstantRangeCount = 1;
          layout_info.pPushConstantRanges = push_constants;
          err = vkCreatePipelineLayout(g_Device, &layout_info, g_Allocator, &g_PipelineLayout);
          check_vk_result(err);
      }
  
      VkPipelineShaderStageCreateInfo stage[2] = {};
      stage[0].sType = VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO;
      stage[0].stage = VK_SHADER_STAGE_VERTEX_BIT;
      stage[0].module = vert_module;
      stage[0].pName = "main";
      stage[1].sType = VK_STRUCTURE_TYPE_PIPELINE_SHADER_STAGE_CREATE_INFO;
      stage[1].stage = VK_SHADER_STAGE_FRAGMENT_BIT;
      stage[1].module = frag_module;
      stage[1].pName = "main";
  
      VkVertexInputBindingDescription binding_desc[1] = {};
      binding_desc[0].stride = sizeof(ImDrawVert);
      binding_desc[0].inputRate = VK_VERTEX_INPUT_RATE_VERTEX;
  
      VkVertexInputAttributeDescription attribute_desc[3] = {};
      attribute_desc[0].location = 0;
      attribute_desc[0].binding = binding_desc[0].binding;
      attribute_desc[0].format = VK_FORMAT_R32G32_SFLOAT;
      attribute_desc[0].offset = IM_OFFSETOF(ImDrawVert, pos);
      attribute_desc[1].location = 1;
      attribute_desc[1].binding = binding_desc[0].binding;
      attribute_desc[1].format = VK_FORMAT_R32G32_SFLOAT;
      attribute_desc[1].offset = IM_OFFSETOF(ImDrawVert, uv);
      attribute_desc[2].location = 2;
      attribute_desc[2].binding = binding_desc[0].binding;
      attribute_desc[2].format = VK_FORMAT_R8G8B8A8_UNORM;
      attribute_desc[2].offset = IM_OFFSETOF(ImDrawVert, col);
  
      VkPipelineVertexInputStateCreateInfo vertex_info = {};
      vertex_info.sType = VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO;
      vertex_info.vertexBindingDescriptionCount = 1;
      vertex_info.pVertexBindingDescriptions = binding_desc;
      vertex_info.vertexAttributeDescriptionCount = 3;
      vertex_info.pVertexAttributeDescriptions = attribute_desc;
  
      VkPipelineInputAssemblyStateCreateInfo ia_info = {};
      ia_info.sType = VK_STRUCTURE_TYPE_PIPELINE_INPUT_ASSEMBLY_STATE_CREATE_INFO;
      ia_info.topology = VK_PRIMITIVE_TOPOLOGY_TRIANGLE_LIST;
  
      VkPipelineViewportStateCreateInfo viewport_info = {};
      viewport_info.sType = VK_STRUCTURE_TYPE_PIPELINE_VIEWPORT_STATE_CREATE_INFO;
      viewport_info.viewportCount = 1;
      viewport_info.scissorCount = 1;
  
      VkPipelineRasterizationStateCreateInfo raster_info = {};
      raster_info.sType = VK_STRUCTURE_TYPE_PIPELINE_RASTERIZATION_STATE_CREATE_INFO;
      raster_info.polygonMode = VK_POLYGON_MODE_FILL;
      raster_info.cullMode = VK_CULL_MODE_NONE;
      raster_info.frontFace = VK_FRONT_FACE_COUNTER_CLOCKWISE;
      raster_info.lineWidth = 1.0f;
  
      VkPipelineMultisampleStateCreateInfo ms_info = {};
      ms_info.sType = VK_STRUCTURE_TYPE_PIPELINE_MULTISAMPLE_STATE_CREATE_INFO;
      ms_info.rasterizationSamples = VK_SAMPLE_COUNT_1_BIT;
  
      VkPipelineColorBlendAttachmentState color_attachment[1] = {};
      color_attachment[0].blendEnable = VK_TRUE;
      color_attachment[0].srcColorBlendFactor = VK_BLEND_FACTOR_SRC_ALPHA;
      color_attachment[0].dstColorBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
      color_attachment[0].colorBlendOp = VK_BLEND_OP_ADD;
      color_attachment[0].srcAlphaBlendFactor = VK_BLEND_FACTOR_ONE_MINUS_SRC_ALPHA;
      color_attachment[0].dstAlphaBlendFactor = VK_BLEND_FACTOR_ZERO;
      color_attachment[0].alphaBlendOp = VK_BLEND_OP_ADD;
      color_attachment[0].colorWriteMask = VK_COLOR_COMPONENT_R_BIT | VK_COLOR_COMPONENT_G_BIT | VK_COLOR_COMPONENT_B_BIT | VK_COLOR_COMPONENT_A_BIT;
  
      VkPipelineDepthStencilStateCreateInfo depth_info = {};
      depth_info.sType = VK_STRUCTURE_TYPE_PIPELINE_DEPTH_STENCIL_STATE_CREATE_INFO;
  
      VkPipelineColorBlendStateCreateInfo blend_info = {};
      blend_info.sType = VK_STRUCTURE_TYPE_PIPELINE_COLOR_BLEND_STATE_CREATE_INFO;
      blend_info.attachmentCount = 1;
      blend_info.pAttachments = color_attachment;
  
      VkDynamicState dynamic_states[2] = { VK_DYNAMIC_STATE_VIEWPORT, VK_DYNAMIC_STATE_SCISSOR };
      VkPipelineDynamicStateCreateInfo dynamic_state = {};
      dynamic_state.sType = VK_STRUCTURE_TYPE_PIPELINE_DYNAMIC_STATE_CREATE_INFO;
      dynamic_state.dynamicStateCount = (uint32_t)IM_ARRAYSIZE(dynamic_states);
      dynamic_state.pDynamicStates = dynamic_states;
  
      VkGraphicsPipelineCreateInfo info = {};
      info.sType = VK_STRUCTURE_TYPE_GRAPHICS_PIPELINE_CREATE_INFO;
      info.flags = g_PipelineCreateFlags;
      info.stageCount = 2;
      info.pStages = stage;
      info.pVertexInputState = &vertex_info;
      info.pInputAssemblyState = &ia_info;
      info.pViewportState = &viewport_info;
      info.pRasterizationState = &raster_info;
      info.pMultisampleState = &ms_info;
      info.pDepthStencilState = &depth_info;
      info.pColorBlendState = &blend_info;
      info.pDynamicState = &dynamic_state;
      info.layout = g_PipelineLayout;
      info.renderPass = g_RenderPass;
      err = vkCreateGraphicsPipelines(g_Device, g_PipelineCache, 1, &info, g_Allocator, &g_Pipeline);
      check_vk_result(err);
  
      vkDestroyShaderModule(g_Device, vert_module, g_Allocator);
      vkDestroyShaderModule(g_Device, frag_module, g_Allocator);
  
      return true;
  }
  
  void    ImGui_ImplVulkan_InvalidateFontUploadObjects()
  {
      if (g_UploadBuffer)
      {
          vkDestroyBuffer(g_Device, g_UploadBuffer, g_Allocator);
          g_UploadBuffer = VK_NULL_HANDLE;
      }
      if (g_UploadBufferMemory)
      {
          vkFreeMemory(g_Device, g_UploadBufferMemory, g_Allocator);
          g_UploadBufferMemory = VK_NULL_HANDLE;
      }
  }
  
  void    ImGui_ImplVulkan_InvalidateDeviceObjects()
  {
      ImGui_ImplVulkan_InvalidateFontUploadObjects();
  
      for (int i = 0; i < IMGUI_VK_QUEUED_FRAMES; i++)
      {
          FrameDataForRender* fd = &g_FramesDataBuffers[i];
          if (fd->VertexBuffer)       { vkDestroyBuffer   (g_Device, fd->VertexBuffer,        g_Allocator); fd->VertexBuffer = VK_NULL_HANDLE; }
          if (fd->VertexBufferMemory) { vkFreeMemory      (g_Device, fd->VertexBufferMemory,  g_Allocator); fd->VertexBufferMemory = VK_NULL_HANDLE; }
          if (fd->IndexBuffer)        { vkDestroyBuffer   (g_Device, fd->IndexBuffer,         g_Allocator); fd->IndexBuffer = VK_NULL_HANDLE; }
          if (fd->IndexBufferMemory)  { vkFreeMemory      (g_Device, fd->IndexBufferMemory,   g_Allocator); fd->IndexBufferMemory = VK_NULL_HANDLE; }
      }
  
      if (g_FontView)             { vkDestroyImageView(g_Device, g_FontView, g_Allocator); g_FontView = VK_NULL_HANDLE; }
      if (g_FontImage)            { vkDestroyImage(g_Device, g_FontImage, g_Allocator); g_FontImage = VK_NULL_HANDLE; }
      if (g_FontMemory)           { vkFreeMemory(g_Device, g_FontMemory, g_Allocator); g_FontMemory = VK_NULL_HANDLE; }
      if (g_FontSampler)          { vkDestroySampler(g_Device, g_FontSampler, g_Allocator); g_FontSampler = VK_NULL_HANDLE; }
      if (g_DescriptorSetLayout)  { vkDestroyDescriptorSetLayout(g_Device, g_DescriptorSetLayout, g_Allocator); g_DescriptorSetLayout = VK_NULL_HANDLE; }
      if (g_PipelineLayout)       { vkDestroyPipelineLayout(g_Device, g_PipelineLayout, g_Allocator); g_PipelineLayout = VK_NULL_HANDLE; }
      if (g_Pipeline)             { vkDestroyPipeline(g_Device, g_Pipeline, g_Allocator); g_Pipeline = VK_NULL_HANDLE; }
  }
  
  bool    ImGui_ImplVulkan_Init(ImGui_ImplVulkan_InitInfo* info, VkRenderPass render_pass)
  {
      ImGuiIO& io = ImGui::GetIO();
      io.BackendRendererName = "imgui_impl_vulkan";
  
      IM_ASSERT(info->Instance != VK_NULL_HANDLE);
      IM_ASSERT(info->PhysicalDevice != VK_NULL_HANDLE);
      IM_ASSERT(info->Device != VK_NULL_HANDLE);
      IM_ASSERT(info->Queue != VK_NULL_HANDLE);
      IM_ASSERT(info->DescriptorPool != VK_NULL_HANDLE);
      IM_ASSERT(render_pass != VK_NULL_HANDLE);
  
      g_Instance = info->Instance;
      g_PhysicalDevice = info->PhysicalDevice;
      g_Device = info->Device;
      g_QueueFamily = info->QueueFamily;
      g_Queue = info->Queue;
      g_RenderPass = render_pass;
      g_PipelineCache = info->PipelineCache;
      g_DescriptorPool = info->DescriptorPool;
      g_Allocator = info->Allocator;
      g_CheckVkResultFn = info->CheckVkResultFn;
  
      ImGui_ImplVulkan_CreateDeviceObjects();
  
      return true;
  }
  
  void ImGui_ImplVulkan_Shutdown()
  {
      ImGui_ImplVulkan_InvalidateDeviceObjects();
  }
  
  void ImGui_ImplVulkan_NewFrame()
  {
  }
  
  
  //-------------------------------------------------------------------------
  // Internal / Miscellaneous Vulkan Helpers
  //-------------------------------------------------------------------------
  // You probably do NOT need to use or care about those functions.
  // Those functions only exist because:
  //   1) they facilitate the readability and maintenance of the multiple main.cpp examples files.
  //   2) the upcoming multi-viewport feature will need them internally.
  // Generally we avoid exposing any kind of superfluous high-level helpers in the bindings,
  // but it is too much code to duplicate everywhere so we exceptionally expose them.
  // Your application/engine will likely already have code to setup all that stuff (swap chain, render pass, frame buffers, etc.).
  // You may read this code to learn about Vulkan, but it is recommended you use you own custom tailored code to do equivalent work.
  // (those functions do not interact with any of the state used by the regular ImGui_ImplVulkan_XXX functions)
  //-------------------------------------------------------------------------
  
  #include <stdlib.h> // malloc
  
  ImGui_ImplVulkanH_FrameData::ImGui_ImplVulkanH_FrameData()
  {
      BackbufferIndex = 0;
      CommandPool = VK_NULL_HANDLE;
      CommandBuffer = VK_NULL_HANDLE;
      Fence = VK_NULL_HANDLE;
      ImageAcquiredSemaphore = VK_NULL_HANDLE;
      RenderCompleteSemaphore = VK_NULL_HANDLE;
  }
  
  ImGui_ImplVulkanH_WindowData::ImGui_ImplVulkanH_WindowData()
  {
      Width = Height = 0;
      Swapchain = VK_NULL_HANDLE;
      Surface = VK_NULL_HANDLE;
      memset(&SurfaceFormat, 0, sizeof(SurfaceFormat));
      PresentMode = VK_PRESENT_MODE_MAX_ENUM_KHR;
      RenderPass = VK_NULL_HANDLE;
      ClearEnable = true;
      memset(&ClearValue, 0, sizeof(ClearValue));
      BackBufferCount = 0;
      memset(&BackBuffer, 0, sizeof(BackBuffer));
      memset(&BackBufferView, 0, sizeof(BackBufferView));
      memset(&Framebuffer, 0, sizeof(Framebuffer));
      FrameIndex = 0;
  }
  
  VkSurfaceFormatKHR ImGui_ImplVulkanH_SelectSurfaceFormat(VkPhysicalDevice physical_device, VkSurfaceKHR surface, const VkFormat* request_formats, int request_formats_count, VkColorSpaceKHR request_color_space)
  {
      IM_ASSERT(request_formats != NULL);
      IM_ASSERT(request_formats_count > 0);
  
      // Per Spec Format and View Format are expected to be the same unless VK_IMAGE_CREATE_MUTABLE_BIT was set at image creation
      // Assuming that the default behavior is without setting this bit, there is no need for separate Swapchain image and image view format
      // Additionally several new color spaces were introduced with Vulkan Spec v1.0.40,
      // hence we must make sure that a format with the mostly available color space, VK_COLOR_SPACE_SRGB_NONLINEAR_KHR, is found and used.
      uint32_t avail_count;
      vkGetPhysicalDeviceSurfaceFormatsKHR(physical_device, surface, &avail_count, NULL);
      ImVector<VkSurfaceFormatKHR> avail_format;
      avail_format.resize((int)avail_count);
      vkGetPhysicalDeviceSurfaceFormatsKHR(physical_device, surface, &avail_count, avail_format.Data);
  
      // First check if only one format, VK_FORMAT_UNDEFINED, is available, which would imply that any format is available
      if (avail_count == 1)
      {
          if (avail_format[0].format == VK_FORMAT_UNDEFINED)
          {
              VkSurfaceFormatKHR ret;
              ret.format = request_formats[0];
              ret.colorSpace = request_color_space;
              return ret;
          }
          else
          {
              // No point in searching another format
              return avail_format[0];
          }
      }
      else
      {
          // Request several formats, the first found will be used
          for (int request_i = 0; request_i < request_formats_count; request_i++)
              for (uint32_t avail_i = 0; avail_i < avail_count; avail_i++)
                  if (avail_format[avail_i].format == request_formats[request_i] && avail_format[avail_i].colorSpace == request_color_space)
                      return avail_format[avail_i];
  
          // If none of the requested image formats could be found, use the first available
          return avail_format[0];
      }
  }
  
  VkPresentModeKHR ImGui_ImplVulkanH_SelectPresentMode(VkPhysicalDevice physical_device, VkSurfaceKHR surface, const VkPresentModeKHR* request_modes, int request_modes_count)
  {
      IM_ASSERT(request_modes != NULL);
      IM_ASSERT(request_modes_count > 0);
  
      // Request a certain mode and confirm that it is available. If not use VK_PRESENT_MODE_FIFO_KHR which is mandatory
      uint32_t avail_count = 0;
      vkGetPhysicalDeviceSurfacePresentModesKHR(physical_device, surface, &avail_count, NULL);
      ImVector<VkPresentModeKHR> avail_modes;
      avail_modes.resize((int)avail_count);
      vkGetPhysicalDeviceSurfacePresentModesKHR(physical_device, surface, &avail_count, avail_modes.Data);
      //for (uint32_t avail_i = 0; avail_i < avail_count; avail_i++)
      //    printf("[vulkan] avail_modes[%d] = %d\n", avail_i, avail_modes[avail_i]);
  
      for (int request_i = 0; request_i < request_modes_count; request_i++)
          for (uint32_t avail_i = 0; avail_i < avail_count; avail_i++)
              if (request_modes[request_i] == avail_modes[avail_i])
                  return request_modes[request_i];
  
      return VK_PRESENT_MODE_FIFO_KHR; // Always available
  }
  
  void ImGui_ImplVulkanH_CreateWindowDataCommandBuffers(VkPhysicalDevice physical_device, VkDevice device, uint32_t queue_family, ImGui_ImplVulkanH_WindowData* wd, const VkAllocationCallbacks* allocator)
  {
      IM_ASSERT(physical_device != VK_NULL_HANDLE && device != VK_NULL_HANDLE);
      (void)physical_device;
      (void)allocator;
  
      // Create Command Buffers
      VkResult err;
      for (int i = 0; i < IMGUI_VK_QUEUED_FRAMES; i++)
      {
          ImGui_ImplVulkanH_FrameData* fd = &wd->Frames[i];
          {
              VkCommandPoolCreateInfo info = {};
              info.sType = VK_STRUCTURE_TYPE_COMMAND_POOL_CREATE_INFO;
              info.flags = VK_COMMAND_POOL_CREATE_RESET_COMMAND_BUFFER_BIT;
              info.queueFamilyIndex = queue_family;
              err = vkCreateCommandPool(device, &info, allocator, &fd->CommandPool);
              check_vk_result(err);
          }
          {
              VkCommandBufferAllocateInfo info = {};
              info.sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO;
              info.commandPool = fd->CommandPool;
              info.level = VK_COMMAND_BUFFER_LEVEL_PRIMARY;
              info.commandBufferCount = 1;
              err = vkAllocateCommandBuffers(device, &info, &fd->CommandBuffer);
              check_vk_result(err);
          }
          {
              VkFenceCreateInfo info = {};
              info.sType = VK_STRUCTURE_TYPE_FENCE_CREATE_INFO;
              info.flags = VK_FENCE_CREATE_SIGNALED_BIT;
              err = vkCreateFence(device, &info, allocator, &fd->Fence);
              check_vk_result(err);
          }
          {
              VkSemaphoreCreateInfo info = {};
              info.sType = VK_STRUCTURE_TYPE_SEMAPHORE_CREATE_INFO;
              err = vkCreateSemaphore(device, &info, allocator, &fd->ImageAcquiredSemaphore);
              check_vk_result(err);
              err = vkCreateSemaphore(device, &info, allocator, &fd->RenderCompleteSemaphore);
              check_vk_result(err);
          }
      }
  }
  
  int ImGui_ImplVulkanH_GetMinImageCountFromPresentMode(VkPresentModeKHR present_mode)
  {
      if (present_mode == VK_PRESENT_MODE_MAILBOX_KHR)
          return 3;
      if (present_mode == VK_PRESENT_MODE_FIFO_KHR || present_mode == VK_PRESENT_MODE_FIFO_RELAXED_KHR)
          return 2;
      if (present_mode == VK_PRESENT_MODE_IMMEDIATE_KHR)
          return 1;
      IM_ASSERT(0);
      return 1;
  }
  
  void ImGui_ImplVulkanH_CreateWindowDataSwapChainAndFramebuffer(VkPhysicalDevice physical_device, VkDevice device, ImGui_ImplVulkanH_WindowData* wd, const VkAllocationCallbacks* allocator, int w, int h)
  {
      uint32_t min_image_count = 2;	// FIXME: this should become a function parameter
  
      VkResult err;
      VkSwapchainKHR old_swapchain = wd->Swapchain;
      err = vkDeviceWaitIdle(device);
      check_vk_result(err);
  
      // Destroy old Framebuffer
      for (uint32_t i = 0; i < wd->BackBufferCount; i++)
      {
          if (wd->BackBufferView[i])
              vkDestroyImageView(device, wd->BackBufferView[i], allocator);
          if (wd->Framebuffer[i])
              vkDestroyFramebuffer(device, wd->Framebuffer[i], allocator);
      }
      wd->BackBufferCount = 0;
      if (wd->RenderPass)
          vkDestroyRenderPass(device, wd->RenderPass, allocator);
  
      // If min image count was not specified, request different count of images dependent on selected present mode
      if (min_image_count == 0)
          min_image_count = ImGui_ImplVulkanH_GetMinImageCountFromPresentMode(wd->PresentMode);
  
      // Create Swapchain
      {
          VkSwapchainCreateInfoKHR info = {};
          info.sType = VK_STRUCTURE_TYPE_SWAPCHAIN_CREATE_INFO_KHR;
          info.surface = wd->Surface;
  		info.minImageCount = min_image_count;
          info.imageFormat = wd->SurfaceFormat.format;
          info.imageColorSpace = wd->SurfaceFormat.colorSpace;
          info.imageArrayLayers = 1;
          info.imageUsage = VK_IMAGE_USAGE_COLOR_ATTACHMENT_BIT;
          info.imageSharingMode = VK_SHARING_MODE_EXCLUSIVE;           // Assume that graphics family == present family
          info.preTransform = VK_SURFACE_TRANSFORM_IDENTITY_BIT_KHR;
          info.compositeAlpha = VK_COMPOSITE_ALPHA_OPAQUE_BIT_KHR;
          info.presentMode = wd->PresentMode;
          info.clipped = VK_TRUE;
          info.oldSwapchain = old_swapchain;
          VkSurfaceCapabilitiesKHR cap;
          err = vkGetPhysicalDeviceSurfaceCapabilitiesKHR(physical_device, wd->Surface, &cap);
          check_vk_result(err);
          if (info.minImageCount < cap.minImageCount)
  			info.minImageCount = cap.minImageCount;
  		else if (cap.maxImageCount != 0 && info.minImageCount > cap.maxImageCount)
  			info.minImageCount = cap.maxImageCount;
  
          if (cap.currentExtent.width == 0xffffffff)
          {
              info.imageExtent.width = wd->Width = w;
              info.imageExtent.height = wd->Height = h;
          }
          else
          {
              info.imageExtent.width = wd->Width = cap.currentExtent.width;
              info.imageExtent.height = wd->Height = cap.currentExtent.height;
          }
          err = vkCreateSwapchainKHR(device, &info, allocator, &wd->Swapchain);
          check_vk_result(err);
          err = vkGetSwapchainImagesKHR(device, wd->Swapchain, &wd->BackBufferCount, NULL);
          check_vk_result(err);
          err = vkGetSwapchainImagesKHR(device, wd->Swapchain, &wd->BackBufferCount, wd->BackBuffer);
          check_vk_result(err);
      }
      if (old_swapchain)
          vkDestroySwapchainKHR(device, old_swapchain, allocator);
  
      // Create the Render Pass
      {
          VkAttachmentDescription attachment = {};
          attachment.format = wd->SurfaceFormat.format;
          attachment.samples = VK_SAMPLE_COUNT_1_BIT;
          attachment.loadOp = wd->ClearEnable ? VK_ATTACHMENT_LOAD_OP_CLEAR : VK_ATTACHMENT_LOAD_OP_DONT_CARE;
          attachment.storeOp = VK_ATTACHMENT_STORE_OP_STORE;
          attachment.stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
          attachment.stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
          attachment.initialLayout = VK_IMAGE_LAYOUT_UNDEFINED;
          attachment.finalLayout = VK_IMAGE_LAYOUT_PRESENT_SRC_KHR;
          VkAttachmentReference color_attachment = {};
          color_attachment.attachment = 0;
          color_attachment.layout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
          VkSubpassDescription subpass = {};
          subpass.pipelineBindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
          subpass.colorAttachmentCount = 1;
          subpass.pColorAttachments = &color_attachment;
          VkSubpassDependency dependency = {};
          dependency.srcSubpass = VK_SUBPASS_EXTERNAL;
          dependency.dstSubpass = 0;
          dependency.srcStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
          dependency.dstStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
          dependency.srcAccessMask = 0;
          dependency.dstAccessMask = VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT;
          VkRenderPassCreateInfo info = {};
          info.sType = VK_STRUCTURE_TYPE_RENDER_PASS_CREATE_INFO;
          info.attachmentCount = 1;
          info.pAttachments = &attachment;
          info.subpassCount = 1;
          info.pSubpasses = &subpass;
          info.dependencyCount = 1;
          info.pDependencies = &dependency;
          err = vkCreateRenderPass(device, &info, allocator, &wd->RenderPass);
          check_vk_result(err);
      }
  
      // Create The Image Views
      {
          VkImageViewCreateInfo info = {};
          info.sType = VK_STRUCTURE_TYPE_IMAGE_VIEW_CREATE_INFO;
          info.viewType = VK_IMAGE_VIEW_TYPE_2D;
          info.format = wd->SurfaceFormat.format;
          info.components.r = VK_COMPONENT_SWIZZLE_R;
          info.components.g = VK_COMPONENT_SWIZZLE_G;
          info.components.b = VK_COMPONENT_SWIZZLE_B;
          info.components.a = VK_COMPONENT_SWIZZLE_A;
          VkImageSubresourceRange image_range = { VK_IMAGE_ASPECT_COLOR_BIT, 0, 1, 0, 1 };
          info.subresourceRange = image_range;
          for (uint32_t i = 0; i < wd->BackBufferCount; i++)
          {
              info.image = wd->BackBuffer[i];
              err = vkCreateImageView(device, &info, allocator, &wd->BackBufferView[i]);
              check_vk_result(err);
          }
      }
  
      // Create Framebuffer
      {
          VkImageView attachment[1];
          VkFramebufferCreateInfo info = {};
          info.sType = VK_STRUCTURE_TYPE_FRAMEBUFFER_CREATE_INFO;
          info.renderPass = wd->RenderPass;
          info.attachmentCount = 1;
          info.pAttachments = attachment;
          info.width = wd->Width;
          info.height = wd->Height;
          info.layers = 1;
          for (uint32_t i = 0; i < wd->BackBufferCount; i++)
          {
              attachment[0] = wd->BackBufferView[i];
              err = vkCreateFramebuffer(device, &info, allocator, &wd->Framebuffer[i]);
              check_vk_result(err);
          }
      }
  }
  
  void ImGui_ImplVulkanH_DestroyWindowData(VkInstance instance, VkDevice device, ImGui_ImplVulkanH_WindowData* wd, const VkAllocationCallbacks* allocator)
  {
      vkDeviceWaitIdle(device); // FIXME: We could wait on the Queue if we had the queue in wd-> (otherwise VulkanH functions can't use globals)
      //vkQueueWaitIdle(g_Queue);
  
      for (int i = 0; i < IMGUI_VK_QUEUED_FRAMES; i++)
      {
          ImGui_ImplVulkanH_FrameData* fd = &wd->Frames[i];
          vkDestroyFence(device, fd->Fence, allocator);
          vkFreeCommandBuffers(device, fd->CommandPool, 1, &fd->CommandBuffer);
          vkDestroyCommandPool(device, fd->CommandPool, allocator);
          vkDestroySemaphore(device, fd->ImageAcquiredSemaphore, allocator);
          vkDestroySemaphore(device, fd->RenderCompleteSemaphore, allocator);
      }
      for (uint32_t i = 0; i < wd->BackBufferCount; i++)
      {
          vkDestroyImageView(device, wd->BackBufferView[i], allocator);
          vkDestroyFramebuffer(device, wd->Framebuffer[i], allocator);
      }
      vkDestroyRenderPass(device, wd->RenderPass, allocator);
      vkDestroySwapchainKHR(device, wd->Swapchain, allocator);
      vkDestroySurfaceKHR(instance, wd->Surface, allocator);
      *wd = ImGui_ImplVulkanH_WindowData();
  }
  #endif
  