text: // dear imgui: Renderer Backend for DirectX12
  // This needs to be used along with a Platform Backend (e.g. Win32)
  
  // Implemented features:
  //  [X] Renderer: User texture binding. Use 'D3D12_GPU_DESCRIPTOR_HANDLE' as ImTextureID. Read the FAQ about
  //  ImTextureID! [X] Renderer: Support for large meshes (64k+ vertices) with 16-bit indices.
  
  // Important: to compile on 32-bit systems, this backend requires code to be compiled with '#define ImTextureID ImU64'.
  // This is because we need ImTextureID to carry a 64-bit value and by default ImTextureID is defined as void*.
  // This define is set in the example .vcxproj file and need to be replicated in your app or by adding it to your
  // imconfig.h file.
  
  // You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
  // Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build
  // the backends you need. If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of
  // imgui.cpp. Read online: https://github.com/ocornut/imgui/tree/master/docs
  
  #pragma once
  #include "imgui.h"      // IMGUI_IMPL_API
  #include <dxgiformat.h> // DXGI_FORMAT
  
  struct ID3D12Device;
  struct ID3D12DescriptorHeap;
  struct ID3D12GraphicsCommandList;
  struct D3D12_CPU_DESCRIPTOR_HANDLE;
  struct D3D12_GPU_DESCRIPTOR_HANDLE;
  
  // cmd_list is the command list that the implementation will use to render imgui draw lists.
  // Before calling the render function, caller must prepare cmd_list by resetting it and setting the appropriate
  // render target and descriptor heap that contains font_srv_cpu_desc_handle/font_srv_gpu_desc_handle.
  // font_srv_cpu_desc_handle and font_srv_gpu_desc_handle are handles to a single SRV descriptor to use for the internal
  // font texture.
  IMGUI_IMPL_API bool ImGui_ImplDX12_Init(ID3D12Device* device, int num_frames_in_flight, DXGI_FORMAT rtv_format,
  	ID3D12DescriptorHeap* cbv_srv_heap, D3D12_CPU_DESCRIPTOR_HANDLE font_srv_cpu_desc_handle,
  	D3D12_GPU_DESCRIPTOR_HANDLE font_srv_gpu_desc_handle);
  IMGUI_IMPL_API void ImGui_ImplDX12_Shutdown();
  IMGUI_IMPL_API void ImGui_ImplDX12_NewFrame();
  IMGUI_IMPL_API void ImGui_ImplDX12_RenderDrawData(
  	ImDrawData* draw_data, ID3D12GraphicsCommandList* graphics_command_list);
  
  // Use if you want to reset your rendering device without losing Dear ImGui state.
  IMGUI_IMPL_API void ImGui_ImplDX12_InvalidateDeviceObjects();
  IMGUI_IMPL_API bool ImGui_ImplDX12_CreateDeviceObjects();
  