examples/directx9_example/imgui_impl_dx9.cpp - external/github.com/ocornut/imgui - Git at Google

 // ImGui Win32 + DirectX9 binding

 // Implemented features:
 //  [X] User texture binding. Use 'LPDIRECT3DTEXTURE9' as ImTextureID. Read the FAQ about ImTextureID in imgui.cpp.

 // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
 // If you use this binding you'll need to call 4 functions: ImGui_ImplXXXX_Init(), ImGui_ImplXXXX_NewFrame(), ImGui::Render() and ImGui_ImplXXXX_Shutdown().
 // If you are new to ImGui, see examples/README.txt and documentation at the top of imgui.cpp.
 // https://github.com/ocornut/imgui

 // CHANGELOG
 // (minor and older changes stripped away, please see git history for details)
 //  2018-05-07: Render: Saving/restoring Transform because they don't seem to be included in the StateBlock. Setting shading mode to Gouraud.
 //  2018-03-20: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors and ImGuiBackendFlags_HasSetMousePos flags + honor ImGuiConfigFlags_NoMouseCursorChange flag.
 //  2018-02-20: Inputs: Added support for mouse cursors (ImGui::GetMouseCursor() value and WM_SETCURSOR message handling).
 //  2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplDX9_RenderDrawData() in the .h file so you can call it yourself.
 //  2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
 //  2018-02-06: Inputs: Honoring the io.WantSetMousePos by repositioning the mouse (when using navigation and ImGuiConfigFlags_NavEnableSetMousePos is set).
 //  2018-02-06: Inputs: Added mapping for ImGuiKey_Space.

 #include "imgui.h"
 #include "imgui_impl_dx9.h"

 // DirectX
 #include <d3d9.h>
 #define DIRECTINPUT_VERSION 0x0800
 #include <dinput.h>

 // Win32 data
 static HWND                     g_hWnd = 0;
 static INT64                    g_Time = 0;
 static INT64                    g_TicksPerSecond = 0;
 static ImGuiMouseCursor         g_LastMouseCursor = ImGuiMouseCursor_COUNT;

 // DirectX data
 static LPDIRECT3DDEVICE9        g_pd3dDevice = NULL;
 static LPDIRECT3DVERTEXBUFFER9  g_pVB = NULL;
 static LPDIRECT3DINDEXBUFFER9   g_pIB = NULL;
 static LPDIRECT3DTEXTURE9       g_FontTexture = NULL;
 static int                      g_VertexBufferSize = 5000, g_IndexBufferSize = 10000;

 struct CUSTOMVERTEX
 {
     float    pos[3];
     D3DCOLOR col;
     float    uv[2];
 };
 #define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_DIFFUSE|D3DFVF_TEX1)

 // 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_ImplDX9_RenderDrawData(ImDrawData* draw_data)
 {
     // Avoid rendering when minimized
     ImGuiIO& io = ImGui::GetIO();
     if (io.DisplaySize.x <= 0.0f || io.DisplaySize.y <= 0.0f)
         return;

     // Create and grow buffers if needed
     if (!g_pVB || g_VertexBufferSize < draw_data->TotalVtxCount)
     {
         if (g_pVB) { g_pVB->Release(); g_pVB = NULL; }
         g_VertexBufferSize = draw_data->TotalVtxCount + 5000;
         if (g_pd3dDevice->CreateVertexBuffer(g_VertexBufferSize * sizeof(CUSTOMVERTEX), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, D3DFVF_CUSTOMVERTEX, D3DPOOL_DEFAULT, &g_pVB, NULL) < 0)
             return;
     }
     if (!g_pIB || g_IndexBufferSize < draw_data->TotalIdxCount)
     {
         if (g_pIB) { g_pIB->Release(); g_pIB = NULL; }
         g_IndexBufferSize = draw_data->TotalIdxCount + 10000;
         if (g_pd3dDevice->CreateIndexBuffer(g_IndexBufferSize * sizeof(ImDrawIdx), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, sizeof(ImDrawIdx) == 2 ? D3DFMT_INDEX16 : D3DFMT_INDEX32, D3DPOOL_DEFAULT, &g_pIB, NULL) < 0)
             return;
     }

     // Backup the DX9 state
     IDirect3DStateBlock9* d3d9_state_block = NULL;
     if (g_pd3dDevice->CreateStateBlock(D3DSBT_ALL, &d3d9_state_block) < 0)
         return;

     // Backup the DX9 transform (DX9 documentation suggests that it is included in the StateBlock but it doesn't appear to)
     D3DMATRIX last_world, last_view, last_projection;
     g_pd3dDevice->GetTransform(D3DTS_WORLD, &last_world);
     g_pd3dDevice->GetTransform(D3DTS_VIEW, &last_view);
     g_pd3dDevice->GetTransform(D3DTS_PROJECTION, &last_projection);

     // Copy and convert all vertices into a single contiguous buffer, convert colors to DX9 default format.
     // FIXME-OPT: This is a waste of resource, the ideal is to use imconfig.h and
     //  1) to avoid repacking colors:   #define IMGUI_USE_BGRA_PACKED_COLOR
     //  2) to avoid repacking vertices: #define IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT struct ImDrawVert { ImVec2 pos; float z; ImU32 col; ImVec2 uv; }
     CUSTOMVERTEX* vtx_dst;
     ImDrawIdx* idx_dst;
     if (g_pVB->Lock(0, (UINT)(draw_data->TotalVtxCount * sizeof(CUSTOMVERTEX)), (void**)&vtx_dst, D3DLOCK_DISCARD) < 0)
         return;
     if (g_pIB->Lock(0, (UINT)(draw_data->TotalIdxCount * sizeof(ImDrawIdx)), (void**)&idx_dst, D3DLOCK_DISCARD) < 0)
         return;
     for (int n = 0; n < draw_data->CmdListsCount; n++)
     {
         const ImDrawList* cmd_list = draw_data->CmdLists[n];
         const ImDrawVert* vtx_src = cmd_list->VtxBuffer.Data;
         for (int i = 0; i < cmd_list->VtxBuffer.Size; i++)
         {
             vtx_dst->pos[0] = vtx_src->pos.x;
             vtx_dst->pos[1] = vtx_src->pos.y;
             vtx_dst->pos[2] = 0.0f;
             vtx_dst->col = (vtx_src->col & 0xFF00FF00) | ((vtx_src->col & 0xFF0000) >> 16) | ((vtx_src->col & 0xFF) << 16);     // RGBA --> ARGB for DirectX9
             vtx_dst->uv[0] = vtx_src->uv.x;
             vtx_dst->uv[1] = vtx_src->uv.y;
             vtx_dst++;
             vtx_src++;
         }
         memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
         idx_dst += cmd_list->IdxBuffer.Size;
     }
     g_pVB->Unlock();
     g_pIB->Unlock();
     g_pd3dDevice->SetStreamSource(0, g_pVB, 0, sizeof(CUSTOMVERTEX));
     g_pd3dDevice->SetIndices(g_pIB);
     g_pd3dDevice->SetFVF(D3DFVF_CUSTOMVERTEX);

     // Setup viewport
     D3DVIEWPORT9 vp;
     vp.X = vp.Y = 0;
     vp.Width = (DWORD)io.DisplaySize.x;
     vp.Height = (DWORD)io.DisplaySize.y;
     vp.MinZ = 0.0f;
     vp.MaxZ = 1.0f;
     g_pd3dDevice->SetViewport(&vp);

     // Setup render state: fixed-pipeline, alpha-blending, no face culling, no depth testing, shade mode (for gradient)
     g_pd3dDevice->SetPixelShader(NULL);
     g_pd3dDevice->SetVertexShader(NULL);
     g_pd3dDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_NONE);
     g_pd3dDevice->SetRenderState(D3DRS_LIGHTING, false);
     g_pd3dDevice->SetRenderState(D3DRS_ZENABLE, false);
     g_pd3dDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, true);
     g_pd3dDevice->SetRenderState(D3DRS_ALPHATESTENABLE, false);
     g_pd3dDevice->SetRenderState(D3DRS_BLENDOP, D3DBLENDOP_ADD);
     g_pd3dDevice->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA);
     g_pd3dDevice->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);
     g_pd3dDevice->SetRenderState(D3DRS_SCISSORTESTENABLE, true);
     g_pd3dDevice->SetRenderState(D3DRS_SHADEMODE, D3DSHADE_GOURAUD);
     g_pd3dDevice->SetTextureStageState(0, D3DTSS_COLOROP, D3DTOP_MODULATE);
     g_pd3dDevice->SetTextureStageState(0, D3DTSS_COLORARG1, D3DTA_TEXTURE);
     g_pd3dDevice->SetTextureStageState(0, D3DTSS_COLORARG2, D3DTA_DIFFUSE);
     g_pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_MODULATE);
     g_pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
     g_pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAARG2, D3DTA_DIFFUSE);
     g_pd3dDevice->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_LINEAR);
     g_pd3dDevice->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_LINEAR);

     // Setup orthographic projection matrix
     // Being agnostic of whether <d3dx9.h> or <DirectXMath.h> can be used, we aren't relying on D3DXMatrixIdentity()/D3DXMatrixOrthoOffCenterLH() or DirectX::XMMatrixIdentity()/DirectX::XMMatrixOrthographicOffCenterLH()
     {
         const float L = 0.5f, R = io.DisplaySize.x+0.5f, T = 0.5f, B = io.DisplaySize.y+0.5f;
         D3DMATRIX mat_identity = { { 1.0f, 0.0f, 0.0f, 0.0f,  0.0f, 1.0f, 0.0f, 0.0f,  0.0f, 0.0f, 1.0f, 0.0f,  0.0f, 0.0f, 0.0f, 1.0f } };
         D3DMATRIX mat_projection =
         {
             2.0f/(R-L),   0.0f,         0.0f,  0.0f,
             0.0f,         2.0f/(T-B),   0.0f,  0.0f,
             0.0f,         0.0f,         0.5f,  0.0f,
             (L+R)/(L-R),  (T+B)/(B-T),  0.5f,  1.0f,
         };
         g_pd3dDevice->SetTransform(D3DTS_WORLD, &mat_identity);
         g_pd3dDevice->SetTransform(D3DTS_VIEW, &mat_identity);
         g_pd3dDevice->SetTransform(D3DTS_PROJECTION, &mat_projection);
     }

     // 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
             {
                 const RECT r = { (LONG)pcmd->ClipRect.x, (LONG)pcmd->ClipRect.y, (LONG)pcmd->ClipRect.z, (LONG)pcmd->ClipRect.w };
                 g_pd3dDevice->SetTexture(0, (LPDIRECT3DTEXTURE9)pcmd->TextureId);
                 g_pd3dDevice->SetScissorRect(&r);
                 g_pd3dDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, vtx_offset, 0, (UINT)cmd_list->VtxBuffer.Size, idx_offset, pcmd->ElemCount/3);
             }
             idx_offset += pcmd->ElemCount;
         }
         vtx_offset += cmd_list->VtxBuffer.Size;
     }

     // Restore the DX9 transform
     g_pd3dDevice->SetTransform(D3DTS_WORLD, &last_world);
     g_pd3dDevice->SetTransform(D3DTS_VIEW, &last_view);
     g_pd3dDevice->SetTransform(D3DTS_PROJECTION, &last_projection);

     // Restore the DX9 state
     d3d9_state_block->Apply();
     d3d9_state_block->Release();
 }

 static bool ImGui_ImplWin32_UpdateMouseCursor()
 {
     ImGuiIO& io = ImGui::GetIO();
     if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
         return false;

     ImGuiMouseCursor imgui_cursor = io.MouseDrawCursor ? ImGuiMouseCursor_None : ImGui::GetMouseCursor();
     if (imgui_cursor == ImGuiMouseCursor_None)
     {
         // Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
         ::SetCursor(NULL);
     }
     else
     {
         // Hardware cursor type
         LPTSTR win32_cursor = IDC_ARROW;
         switch (imgui_cursor)
         {
         case ImGuiMouseCursor_Arrow:        win32_cursor = IDC_ARROW; break;
         case ImGuiMouseCursor_TextInput:    win32_cursor = IDC_IBEAM; break;
         case ImGuiMouseCursor_ResizeAll:    win32_cursor = IDC_SIZEALL; break;
         case ImGuiMouseCursor_ResizeEW:     win32_cursor = IDC_SIZEWE; break;
         case ImGuiMouseCursor_ResizeNS:     win32_cursor = IDC_SIZENS; break;
         case ImGuiMouseCursor_ResizeNESW:   win32_cursor = IDC_SIZENESW; break;
         case ImGuiMouseCursor_ResizeNWSE:   win32_cursor = IDC_SIZENWSE; break;
         }
         ::SetCursor(::LoadCursor(NULL, win32_cursor));
     }
     return true;
 }

 // Allow compilation with old Windows SDK. MinGW doesn't have default _WIN32_WINNT/WINVER versions.
 #ifndef WM_MOUSEHWHEEL
 #define WM_MOUSEHWHEEL 0x020E
 #endif

 // Process Win32 mouse/keyboard inputs.
 // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
 // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application.
 // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application.
 // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
 // PS: In this Win32 handler, we use the capture API (GetCapture/SetCapture/ReleaseCapture) to be able to read mouse coordinations when dragging mouse outside of our window bounds.
 // PS: We treat DBLCLK messages as regular mouse down messages, so this code will work on windows classes that have the CS_DBLCLKS flag set. Our own example app code doesn't set this flag.
 IMGUI_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
 {
     if (ImGui::GetCurrentContext() == NULL)
         return 0;

     ImGuiIO& io = ImGui::GetIO();
     switch (msg)
     {
     case WM_LBUTTONDOWN: case WM_LBUTTONDBLCLK:
     case WM_RBUTTONDOWN: case WM_RBUTTONDBLCLK:
     case WM_MBUTTONDOWN: case WM_MBUTTONDBLCLK:
     {
         int button = 0;
         if (msg == WM_LBUTTONDOWN || msg == WM_LBUTTONDBLCLK) button = 0;
         if (msg == WM_RBUTTONDOWN || msg == WM_RBUTTONDBLCLK) button = 1;
         if (msg == WM_MBUTTONDOWN || msg == WM_MBUTTONDBLCLK) button = 2;
         if (!ImGui::IsAnyMouseDown() && ::GetCapture() == NULL)
             ::SetCapture(hwnd);
         io.MouseDown[button] = true;
         return 0;
     }
     case WM_LBUTTONUP:
     case WM_RBUTTONUP:
     case WM_MBUTTONUP:
     {
         int button = 0;
         if (msg == WM_LBUTTONUP) button = 0;
         if (msg == WM_RBUTTONUP) button = 1;
         if (msg == WM_MBUTTONUP) button = 2;
         io.MouseDown[button] = false;
         if (!ImGui::IsAnyMouseDown() && ::GetCapture() == hwnd)
             ::ReleaseCapture();
         return 0;
     }
     case WM_MOUSEWHEEL:
         io.MouseWheel += GET_WHEEL_DELTA_WPARAM(wParam) > 0 ? +1.0f : -1.0f;
         return 0;
     case WM_MOUSEHWHEEL:
         io.MouseWheelH += GET_WHEEL_DELTA_WPARAM(wParam) > 0 ? +1.0f : -1.0f;
         return 0;
     case WM_MOUSEMOVE:
         io.MousePos.x = (signed short)(lParam);
         io.MousePos.y = (signed short)(lParam >> 16);
         return 0;
     case WM_KEYDOWN:
     case WM_SYSKEYDOWN:
         if (wParam < 256)
             io.KeysDown[wParam] = 1;
         return 0;
     case WM_KEYUP:
     case WM_SYSKEYUP:
         if (wParam < 256)
             io.KeysDown[wParam] = 0;
         return 0;
     case WM_CHAR:
         // You can also use ToAscii()+GetKeyboardState() to retrieve characters.
         if (wParam > 0 && wParam < 0x10000)
             io.AddInputCharacter((unsigned short)wParam);
         return 0;
     case WM_SETCURSOR:
         if (LOWORD(lParam) == HTCLIENT && ImGui_ImplWin32_UpdateMouseCursor())
             return 1;
         return 0;
     }
     return 0;
 }

 bool    ImGui_ImplDX9_Init(void* hwnd, IDirect3DDevice9* device)
 {
     g_hWnd = (HWND)hwnd;
     g_pd3dDevice = device;

     if (!QueryPerformanceFrequency((LARGE_INTEGER *)&g_TicksPerSecond))
         return false;
     if (!QueryPerformanceCounter((LARGE_INTEGER *)&g_Time))
         return false;

     // Setup back-end capabilities flags
     ImGuiIO& io = ImGui::GetIO();
     io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;   // We can honor GetMouseCursor() values (optional)
     io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;    // We can honor io.WantSetMousePos requests (optional, rarely used)

     // Keyboard mapping. ImGui will use those indices to peek into the io.KeysDown[] array that we will update during the application lifetime.
     io.KeyMap[ImGuiKey_Tab] = VK_TAB;
     io.KeyMap[ImGuiKey_LeftArrow] = VK_LEFT;
     io.KeyMap[ImGuiKey_RightArrow] = VK_RIGHT;
     io.KeyMap[ImGuiKey_UpArrow] = VK_UP;
     io.KeyMap[ImGuiKey_DownArrow] = VK_DOWN;
     io.KeyMap[ImGuiKey_PageUp] = VK_PRIOR;
     io.KeyMap[ImGuiKey_PageDown] = VK_NEXT;
     io.KeyMap[ImGuiKey_Home] = VK_HOME;
     io.KeyMap[ImGuiKey_End] = VK_END;
     io.KeyMap[ImGuiKey_Insert] = VK_INSERT;
     io.KeyMap[ImGuiKey_Delete] = VK_DELETE;
     io.KeyMap[ImGuiKey_Backspace] = VK_BACK;
     io.KeyMap[ImGuiKey_Space] = VK_SPACE;
     io.KeyMap[ImGuiKey_Enter] = VK_RETURN;
     io.KeyMap[ImGuiKey_Escape] = VK_ESCAPE;
     io.KeyMap[ImGuiKey_A] = 'A';
     io.KeyMap[ImGuiKey_C] = 'C';
     io.KeyMap[ImGuiKey_V] = 'V';
     io.KeyMap[ImGuiKey_X] = 'X';
     io.KeyMap[ImGuiKey_Y] = 'Y';
     io.KeyMap[ImGuiKey_Z] = 'Z';

     io.ImeWindowHandle = g_hWnd;

     return true;
 }

 void ImGui_ImplDX9_Shutdown()
 {
     ImGui_ImplDX9_InvalidateDeviceObjects();
     g_pd3dDevice = NULL;
     g_hWnd = 0;
 }

 static bool ImGui_ImplDX9_CreateFontsTexture()
 {
     // Build texture atlas
     ImGuiIO& io = ImGui::GetIO();
     unsigned char* pixels;
     int width, height, bytes_per_pixel;
     io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height, &bytes_per_pixel);

     // Upload texture to graphics system
     g_FontTexture = NULL;
     if (g_pd3dDevice->CreateTexture(width, height, 1, D3DUSAGE_DYNAMIC, D3DFMT_A8R8G8B8, D3DPOOL_DEFAULT, &g_FontTexture, NULL) < 0)
         return false;
     D3DLOCKED_RECT tex_locked_rect;
     if (g_FontTexture->LockRect(0, &tex_locked_rect, NULL, 0) != D3D_OK)
         return false;
     for (int y = 0; y < height; y++)
         memcpy((unsigned char *)tex_locked_rect.pBits + tex_locked_rect.Pitch * y, pixels + (width * bytes_per_pixel) * y, (width * bytes_per_pixel));
     g_FontTexture->UnlockRect(0);

     // Store our identifier
     io.Fonts->TexID = (void *)g_FontTexture;

     return true;
 }

 bool ImGui_ImplDX9_CreateDeviceObjects()
 {
     if (!g_pd3dDevice)
         return false;
     if (!ImGui_ImplDX9_CreateFontsTexture())
         return false;
     return true;
 }

 void ImGui_ImplDX9_InvalidateDeviceObjects()
 {
     if (!g_pd3dDevice)
         return;
     if (g_pVB)
     {
         g_pVB->Release();
         g_pVB = NULL;
     }
     if (g_pIB)
     {
         g_pIB->Release();
         g_pIB = NULL;
     }

     // At this point note that we set ImGui::GetIO().Fonts->TexID to be == g_FontTexture, so clear both.
     ImGuiIO& io = ImGui::GetIO();
     IM_ASSERT(g_FontTexture == io.Fonts->TexID);
     if (g_FontTexture)
         g_FontTexture->Release();
     g_FontTexture = NULL;
     io.Fonts->TexID = NULL;
 }

 void ImGui_ImplDX9_NewFrame()
 {
     if (!g_FontTexture)
         ImGui_ImplDX9_CreateDeviceObjects();

     ImGuiIO& io = ImGui::GetIO();

     // Setup display size (every frame to accommodate for window resizing)
     RECT rect;
     GetClientRect(g_hWnd, &rect);
     io.DisplaySize = ImVec2((float)(rect.right - rect.left), (float)(rect.bottom - rect.top));

     // Setup time step
     INT64 current_time;
     QueryPerformanceCounter((LARGE_INTEGER *)&current_time);
     io.DeltaTime = (float)(current_time - g_Time) / g_TicksPerSecond;
     g_Time = current_time;

     // Read keyboard modifiers inputs
     io.KeyCtrl = (GetKeyState(VK_CONTROL) & 0x8000) != 0;
     io.KeyShift = (GetKeyState(VK_SHIFT) & 0x8000) != 0;
     io.KeyAlt = (GetKeyState(VK_MENU) & 0x8000) != 0;
     io.KeySuper = false;
     // io.KeysDown : filled by WM_KEYDOWN/WM_KEYUP events
     // io.MousePos : filled by WM_MOUSEMOVE events
     // io.MouseDown : filled by WM_*BUTTON* events
     // io.MouseWheel : filled by WM_MOUSEWHEEL events

     // Set OS mouse position if requested (only used when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
     if (io.WantSetMousePos)
     {
         POINT pos = { (int)io.MousePos.x, (int)io.MousePos.y };
         ClientToScreen(g_hWnd, &pos);
         SetCursorPos(pos.x, pos.y);
     }

     // Update OS mouse cursor with the cursor requested by imgui
     ImGuiMouseCursor mouse_cursor = io.MouseDrawCursor ? ImGuiMouseCursor_None : ImGui::GetMouseCursor();
     if (g_LastMouseCursor != mouse_cursor)
     {
         g_LastMouseCursor = mouse_cursor;
         ImGui_ImplWin32_UpdateMouseCursor();
     }

     // Start the frame. This call will update the io.WantCaptureMouse, io.WantCaptureKeyboard flag that you can use to dispatch inputs (or not) to your application.
     ImGui::NewFrame();
 }
	// ImGui Win32 + DirectX9 binding

	// Implemented features:
	// [X] User texture binding. Use 'LPDIRECT3DTEXTURE9' as ImTextureID. Read the FAQ about ImTextureID in imgui.cpp.

	// You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
	// If you use this binding you'll need to call 4 functions: ImGui_ImplXXXX_Init(), ImGui_ImplXXXX_NewFrame(), ImGui::Render() and ImGui_ImplXXXX_Shutdown().
	// If you are new to ImGui, see examples/README.txt and documentation at the top of imgui.cpp.
	// https://github.com/ocornut/imgui

	// CHANGELOG
	// (minor and older changes stripped away, please see git history for details)
	// 2018-05-07: Render: Saving/restoring Transform because they don't seem to be included in the StateBlock. Setting shading mode to Gouraud.
	// 2018-03-20: Misc: Setup io.BackendFlags ImGuiBackendFlags_HasMouseCursors and ImGuiBackendFlags_HasSetMousePos flags + honor ImGuiConfigFlags_NoMouseCursorChange flag.
	// 2018-02-20: Inputs: Added support for mouse cursors (ImGui::GetMouseCursor() value and WM_SETCURSOR message handling).
	// 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplDX9_RenderDrawData() in the .h file so you can call it yourself.
	// 2018-02-06: Misc: Removed call to ImGui::Shutdown() which is not available from 1.60 WIP, user needs to call CreateContext/DestroyContext themselves.
	// 2018-02-06: Inputs: Honoring the io.WantSetMousePos by repositioning the mouse (when using navigation and ImGuiConfigFlags_NavEnableSetMousePos is set).
	// 2018-02-06: Inputs: Added mapping for ImGuiKey_Space.

	#include "imgui.h"
	#include "imgui_impl_dx9.h"

	// DirectX
	#include <d3d9.h>
	#define DIRECTINPUT_VERSION 0x0800
	#include <dinput.h>

	// Win32 data
	static HWND g_hWnd = 0;
	static INT64 g_Time = 0;
	static INT64 g_TicksPerSecond = 0;
	static ImGuiMouseCursor g_LastMouseCursor = ImGuiMouseCursor_COUNT;

	// DirectX data
	static LPDIRECT3DDEVICE9 g_pd3dDevice = NULL;
	static LPDIRECT3DVERTEXBUFFER9 g_pVB = NULL;
	static LPDIRECT3DINDEXBUFFER9 g_pIB = NULL;
	static LPDIRECT3DTEXTURE9 g_FontTexture = NULL;
	static int g_VertexBufferSize = 5000, g_IndexBufferSize = 10000;

	struct CUSTOMVERTEX
	{
	float pos[3];
	D3DCOLOR col;
	float uv[2];
	};
	#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ\|D3DFVF_DIFFUSE\|D3DFVF_TEX1)

	// 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_ImplDX9_RenderDrawData(ImDrawData* draw_data)
	{
	// Avoid rendering when minimized
	ImGuiIO& io = ImGui::GetIO();
	if (io.DisplaySize.x <= 0.0f \|\| io.DisplaySize.y <= 0.0f)
	return;

	// Create and grow buffers if needed
	if (!g_pVB \|\| g_VertexBufferSize < draw_data->TotalVtxCount)
	{
	if (g_pVB) { g_pVB->Release(); g_pVB = NULL; }
	g_VertexBufferSize = draw_data->TotalVtxCount + 5000;
	if (g_pd3dDevice->CreateVertexBuffer(g_VertexBufferSize * sizeof(CUSTOMVERTEX), D3DUSAGE_DYNAMIC \| D3DUSAGE_WRITEONLY, D3DFVF_CUSTOMVERTEX, D3DPOOL_DEFAULT, &g_pVB, NULL) < 0)
	return;
	}
	if (!g_pIB \|\| g_IndexBufferSize < draw_data->TotalIdxCount)
	{
	if (g_pIB) { g_pIB->Release(); g_pIB = NULL; }
	g_IndexBufferSize = draw_data->TotalIdxCount + 10000;
	if (g_pd3dDevice->CreateIndexBuffer(g_IndexBufferSize * sizeof(ImDrawIdx), D3DUSAGE_DYNAMIC \| D3DUSAGE_WRITEONLY, sizeof(ImDrawIdx) == 2 ? D3DFMT_INDEX16 : D3DFMT_INDEX32, D3DPOOL_DEFAULT, &g_pIB, NULL) < 0)
	return;
	}

	// Backup the DX9 state
	IDirect3DStateBlock9* d3d9_state_block = NULL;
	if (g_pd3dDevice->CreateStateBlock(D3DSBT_ALL, &d3d9_state_block) < 0)
	return;

	// Backup the DX9 transform (DX9 documentation suggests that it is included in the StateBlock but it doesn't appear to)
	D3DMATRIX last_world, last_view, last_projection;
	g_pd3dDevice->GetTransform(D3DTS_WORLD, &last_world);
	g_pd3dDevice->GetTransform(D3DTS_VIEW, &last_view);
	g_pd3dDevice->GetTransform(D3DTS_PROJECTION, &last_projection);

	// Copy and convert all vertices into a single contiguous buffer, convert colors to DX9 default format.
	// FIXME-OPT: This is a waste of resource, the ideal is to use imconfig.h and
	// 1) to avoid repacking colors: #define IMGUI_USE_BGRA_PACKED_COLOR
	// 2) to avoid repacking vertices: #define IMGUI_OVERRIDE_DRAWVERT_STRUCT_LAYOUT struct ImDrawVert { ImVec2 pos; float z; ImU32 col; ImVec2 uv; }
	CUSTOMVERTEX* vtx_dst;
	ImDrawIdx* idx_dst;
	if (g_pVB->Lock(0, (UINT)(draw_data->TotalVtxCount * sizeof(CUSTOMVERTEX)), (void**)&vtx_dst, D3DLOCK_DISCARD) < 0)
	return;
	if (g_pIB->Lock(0, (UINT)(draw_data->TotalIdxCount * sizeof(ImDrawIdx)), (void**)&idx_dst, D3DLOCK_DISCARD) < 0)
	return;
	for (int n = 0; n < draw_data->CmdListsCount; n++)
	{
	const ImDrawList* cmd_list = draw_data->CmdLists[n];
	const ImDrawVert* vtx_src = cmd_list->VtxBuffer.Data;
	for (int i = 0; i < cmd_list->VtxBuffer.Size; i++)
	{
	vtx_dst->pos[0] = vtx_src->pos.x;
	vtx_dst->pos[1] = vtx_src->pos.y;
	vtx_dst->pos[2] = 0.0f;
	vtx_dst->col = (vtx_src->col & 0xFF00FF00) \| ((vtx_src->col & 0xFF0000) >> 16) \| ((vtx_src->col & 0xFF) << 16); // RGBA --> ARGB for DirectX9
	vtx_dst->uv[0] = vtx_src->uv.x;
	vtx_dst->uv[1] = vtx_src->uv.y;
	vtx_dst++;
	vtx_src++;
	}
	memcpy(idx_dst, cmd_list->IdxBuffer.Data, cmd_list->IdxBuffer.Size * sizeof(ImDrawIdx));
	idx_dst += cmd_list->IdxBuffer.Size;
	}
	g_pVB->Unlock();
	g_pIB->Unlock();
	g_pd3dDevice->SetStreamSource(0, g_pVB, 0, sizeof(CUSTOMVERTEX));
	g_pd3dDevice->SetIndices(g_pIB);
	g_pd3dDevice->SetFVF(D3DFVF_CUSTOMVERTEX);

	// Setup viewport
	D3DVIEWPORT9 vp;
	vp.X = vp.Y = 0;
	vp.Width = (DWORD)io.DisplaySize.x;
	vp.Height = (DWORD)io.DisplaySize.y;
	vp.MinZ = 0.0f;
	vp.MaxZ = 1.0f;
	g_pd3dDevice->SetViewport(&vp);

	// Setup render state: fixed-pipeline, alpha-blending, no face culling, no depth testing, shade mode (for gradient)
	g_pd3dDevice->SetPixelShader(NULL);
	g_pd3dDevice->SetVertexShader(NULL);
	g_pd3dDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_NONE);
	g_pd3dDevice->SetRenderState(D3DRS_LIGHTING, false);
	g_pd3dDevice->SetRenderState(D3DRS_ZENABLE, false);
	g_pd3dDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, true);
	g_pd3dDevice->SetRenderState(D3DRS_ALPHATESTENABLE, false);
	g_pd3dDevice->SetRenderState(D3DRS_BLENDOP, D3DBLENDOP_ADD);
	g_pd3dDevice->SetRenderState(D3DRS_SRCBLEND, D3DBLEND_SRCALPHA);
	g_pd3dDevice->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_INVSRCALPHA);
	g_pd3dDevice->SetRenderState(D3DRS_SCISSORTESTENABLE, true);
	g_pd3dDevice->SetRenderState(D3DRS_SHADEMODE, D3DSHADE_GOURAUD);
	g_pd3dDevice->SetTextureStageState(0, D3DTSS_COLOROP, D3DTOP_MODULATE);
	g_pd3dDevice->SetTextureStageState(0, D3DTSS_COLORARG1, D3DTA_TEXTURE);
	g_pd3dDevice->SetTextureStageState(0, D3DTSS_COLORARG2, D3DTA_DIFFUSE);
	g_pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAOP, D3DTOP_MODULATE);
	g_pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAARG1, D3DTA_TEXTURE);
	g_pd3dDevice->SetTextureStageState(0, D3DTSS_ALPHAARG2, D3DTA_DIFFUSE);
	g_pd3dDevice->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_LINEAR);
	g_pd3dDevice->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_LINEAR);

	// Setup orthographic projection matrix
	// Being agnostic of whether <d3dx9.h> or <DirectXMath.h> can be used, we aren't relying on D3DXMatrixIdentity()/D3DXMatrixOrthoOffCenterLH() or DirectX::XMMatrixIdentity()/DirectX::XMMatrixOrthographicOffCenterLH()
	{
	const float L = 0.5f, R = io.DisplaySize.x+0.5f, T = 0.5f, B = io.DisplaySize.y+0.5f;
	D3DMATRIX mat_identity = { { 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f } };
	D3DMATRIX mat_projection =
	{
	2.0f/(R-L), 0.0f, 0.0f, 0.0f,
	0.0f, 2.0f/(T-B), 0.0f, 0.0f,
	0.0f, 0.0f, 0.5f, 0.0f,
	(L+R)/(L-R), (T+B)/(B-T), 0.5f, 1.0f,
	};
	g_pd3dDevice->SetTransform(D3DTS_WORLD, &mat_identity);
	g_pd3dDevice->SetTransform(D3DTS_VIEW, &mat_identity);
	g_pd3dDevice->SetTransform(D3DTS_PROJECTION, &mat_projection);
	}

	// 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
	{
	const RECT r = { (LONG)pcmd->ClipRect.x, (LONG)pcmd->ClipRect.y, (LONG)pcmd->ClipRect.z, (LONG)pcmd->ClipRect.w };
	g_pd3dDevice->SetTexture(0, (LPDIRECT3DTEXTURE9)pcmd->TextureId);
	g_pd3dDevice->SetScissorRect(&r);
	g_pd3dDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, vtx_offset, 0, (UINT)cmd_list->VtxBuffer.Size, idx_offset, pcmd->ElemCount/3);
	}
	idx_offset += pcmd->ElemCount;
	}
	vtx_offset += cmd_list->VtxBuffer.Size;
	}

	// Restore the DX9 transform
	g_pd3dDevice->SetTransform(D3DTS_WORLD, &last_world);
	g_pd3dDevice->SetTransform(D3DTS_VIEW, &last_view);
	g_pd3dDevice->SetTransform(D3DTS_PROJECTION, &last_projection);

	// Restore the DX9 state
	d3d9_state_block->Apply();
	d3d9_state_block->Release();
	}

	static bool ImGui_ImplWin32_UpdateMouseCursor()
	{
	ImGuiIO& io = ImGui::GetIO();
	if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
	return false;

	ImGuiMouseCursor imgui_cursor = io.MouseDrawCursor ? ImGuiMouseCursor_None : ImGui::GetMouseCursor();
	if (imgui_cursor == ImGuiMouseCursor_None)
	{
	// Hide OS mouse cursor if imgui is drawing it or if it wants no cursor
	::SetCursor(NULL);
	}
	else
	{
	// Hardware cursor type
	LPTSTR win32_cursor = IDC_ARROW;
	switch (imgui_cursor)
	{
	case ImGuiMouseCursor_Arrow: win32_cursor = IDC_ARROW; break;
	case ImGuiMouseCursor_TextInput: win32_cursor = IDC_IBEAM; break;
	case ImGuiMouseCursor_ResizeAll: win32_cursor = IDC_SIZEALL; break;
	case ImGuiMouseCursor_ResizeEW: win32_cursor = IDC_SIZEWE; break;
	case ImGuiMouseCursor_ResizeNS: win32_cursor = IDC_SIZENS; break;
	case ImGuiMouseCursor_ResizeNESW: win32_cursor = IDC_SIZENESW; break;
	case ImGuiMouseCursor_ResizeNWSE: win32_cursor = IDC_SIZENWSE; break;
	}
	::SetCursor(::LoadCursor(NULL, win32_cursor));
	}
	return true;
	}

	// Allow compilation with old Windows SDK. MinGW doesn't have default _WIN32_WINNT/WINVER versions.
	#ifndef WM_MOUSEHWHEEL
	#define WM_MOUSEHWHEEL 0x020E
	#endif

	// Process Win32 mouse/keyboard inputs.
	// You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
	// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application.
	// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application.
	// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
	// PS: In this Win32 handler, we use the capture API (GetCapture/SetCapture/ReleaseCapture) to be able to read mouse coordinations when dragging mouse outside of our window bounds.
	// PS: We treat DBLCLK messages as regular mouse down messages, so this code will work on windows classes that have the CS_DBLCLKS flag set. Our own example app code doesn't set this flag.
	IMGUI_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
	{
	if (ImGui::GetCurrentContext() == NULL)
	return 0;

	ImGuiIO& io = ImGui::GetIO();
	switch (msg)
	{
	case WM_LBUTTONDOWN: case WM_LBUTTONDBLCLK:
	case WM_RBUTTONDOWN: case WM_RBUTTONDBLCLK:
	case WM_MBUTTONDOWN: case WM_MBUTTONDBLCLK:
	{
	int button = 0;
	if (msg == WM_LBUTTONDOWN \|\| msg == WM_LBUTTONDBLCLK) button = 0;
	if (msg == WM_RBUTTONDOWN \|\| msg == WM_RBUTTONDBLCLK) button = 1;
	if (msg == WM_MBUTTONDOWN \|\| msg == WM_MBUTTONDBLCLK) button = 2;
	if (!ImGui::IsAnyMouseDown() && ::GetCapture() == NULL)
	::SetCapture(hwnd);
	io.MouseDown[button] = true;
	return 0;
	}
	case WM_LBUTTONUP:
	case WM_RBUTTONUP:
	case WM_MBUTTONUP:
	{
	int button = 0;
	if (msg == WM_LBUTTONUP) button = 0;
	if (msg == WM_RBUTTONUP) button = 1;
	if (msg == WM_MBUTTONUP) button = 2;
	io.MouseDown[button] = false;
	if (!ImGui::IsAnyMouseDown() && ::GetCapture() == hwnd)
	::ReleaseCapture();
	return 0;
	}
	case WM_MOUSEWHEEL:
	io.MouseWheel += GET_WHEEL_DELTA_WPARAM(wParam) > 0 ? +1.0f : -1.0f;
	return 0;
	case WM_MOUSEHWHEEL:
	io.MouseWheelH += GET_WHEEL_DELTA_WPARAM(wParam) > 0 ? +1.0f : -1.0f;
	return 0;
	case WM_MOUSEMOVE:
	io.MousePos.x = (signed short)(lParam);
	io.MousePos.y = (signed short)(lParam >> 16);
	return 0;
	case WM_KEYDOWN:
	case WM_SYSKEYDOWN:
	if (wParam < 256)
	io.KeysDown[wParam] = 1;
	return 0;
	case WM_KEYUP:
	case WM_SYSKEYUP:
	if (wParam < 256)
	io.KeysDown[wParam] = 0;
	return 0;
	case WM_CHAR:
	// You can also use ToAscii()+GetKeyboardState() to retrieve characters.
	if (wParam > 0 && wParam < 0x10000)
	io.AddInputCharacter((unsigned short)wParam);
	return 0;
	case WM_SETCURSOR:
	if (LOWORD(lParam) == HTCLIENT && ImGui_ImplWin32_UpdateMouseCursor())
	return 1;
	return 0;
	}
	return 0;
	}

	bool ImGui_ImplDX9_Init(void* hwnd, IDirect3DDevice9* device)
	{
	g_hWnd = (HWND)hwnd;
	g_pd3dDevice = device;

	if (!QueryPerformanceFrequency((LARGE_INTEGER *)&g_TicksPerSecond))
	return false;
	if (!QueryPerformanceCounter((LARGE_INTEGER *)&g_Time))
	return false;

	// Setup back-end capabilities flags
	ImGuiIO& io = ImGui::GetIO();
	io.BackendFlags \|= ImGuiBackendFlags_HasMouseCursors; // We can honor GetMouseCursor() values (optional)
	io.BackendFlags \|= ImGuiBackendFlags_HasSetMousePos; // We can honor io.WantSetMousePos requests (optional, rarely used)

	// Keyboard mapping. ImGui will use those indices to peek into the io.KeysDown[] array that we will update during the application lifetime.
	io.KeyMap[ImGuiKey_Tab] = VK_TAB;
	io.KeyMap[ImGuiKey_LeftArrow] = VK_LEFT;
	io.KeyMap[ImGuiKey_RightArrow] = VK_RIGHT;
	io.KeyMap[ImGuiKey_UpArrow] = VK_UP;
	io.KeyMap[ImGuiKey_DownArrow] = VK_DOWN;
	io.KeyMap[ImGuiKey_PageUp] = VK_PRIOR;
	io.KeyMap[ImGuiKey_PageDown] = VK_NEXT;
	io.KeyMap[ImGuiKey_Home] = VK_HOME;
	io.KeyMap[ImGuiKey_End] = VK_END;
	io.KeyMap[ImGuiKey_Insert] = VK_INSERT;
	io.KeyMap[ImGuiKey_Delete] = VK_DELETE;
	io.KeyMap[ImGuiKey_Backspace] = VK_BACK;
	io.KeyMap[ImGuiKey_Space] = VK_SPACE;
	io.KeyMap[ImGuiKey_Enter] = VK_RETURN;
	io.KeyMap[ImGuiKey_Escape] = VK_ESCAPE;
	io.KeyMap[ImGuiKey_A] = 'A';
	io.KeyMap[ImGuiKey_C] = 'C';
	io.KeyMap[ImGuiKey_V] = 'V';
	io.KeyMap[ImGuiKey_X] = 'X';
	io.KeyMap[ImGuiKey_Y] = 'Y';
	io.KeyMap[ImGuiKey_Z] = 'Z';

	io.ImeWindowHandle = g_hWnd;

	return true;
	}

	void ImGui_ImplDX9_Shutdown()
	{
	ImGui_ImplDX9_InvalidateDeviceObjects();
	g_pd3dDevice = NULL;
	g_hWnd = 0;
	}

	static bool ImGui_ImplDX9_CreateFontsTexture()
	{
	// Build texture atlas
	ImGuiIO& io = ImGui::GetIO();
	unsigned char* pixels;
	int width, height, bytes_per_pixel;
	io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height, &bytes_per_pixel);

	// Upload texture to graphics system
	g_FontTexture = NULL;
	if (g_pd3dDevice->CreateTexture(width, height, 1, D3DUSAGE_DYNAMIC, D3DFMT_A8R8G8B8, D3DPOOL_DEFAULT, &g_FontTexture, NULL) < 0)
	return false;
	D3DLOCKED_RECT tex_locked_rect;
	if (g_FontTexture->LockRect(0, &tex_locked_rect, NULL, 0) != D3D_OK)
	return false;
	for (int y = 0; y < height; y++)
	memcpy((unsigned char )tex_locked_rect.pBits + tex_locked_rect.Pitch y, pixels + (width * bytes_per_pixel) * y, (width * bytes_per_pixel));
	g_FontTexture->UnlockRect(0);

	// Store our identifier
	io.Fonts->TexID = (void *)g_FontTexture;

	return true;
	}

	bool ImGui_ImplDX9_CreateDeviceObjects()
	{
	if (!g_pd3dDevice)
	return false;
	if (!ImGui_ImplDX9_CreateFontsTexture())
	return false;
	return true;
	}

	void ImGui_ImplDX9_InvalidateDeviceObjects()
	{
	if (!g_pd3dDevice)
	return;
	if (g_pVB)
	{
	g_pVB->Release();
	g_pVB = NULL;
	}
	if (g_pIB)
	{
	g_pIB->Release();
	g_pIB = NULL;
	}

	// At this point note that we set ImGui::GetIO().Fonts->TexID to be == g_FontTexture, so clear both.
	ImGuiIO& io = ImGui::GetIO();
	IM_ASSERT(g_FontTexture == io.Fonts->TexID);
	if (g_FontTexture)
	g_FontTexture->Release();
	g_FontTexture = NULL;
	io.Fonts->TexID = NULL;
	}

	void ImGui_ImplDX9_NewFrame()
	{
	if (!g_FontTexture)
	ImGui_ImplDX9_CreateDeviceObjects();

	ImGuiIO& io = ImGui::GetIO();

	// Setup display size (every frame to accommodate for window resizing)
	RECT rect;
	GetClientRect(g_hWnd, &rect);
	io.DisplaySize = ImVec2((float)(rect.right - rect.left), (float)(rect.bottom - rect.top));

	// Setup time step
	INT64 current_time;
	QueryPerformanceCounter((LARGE_INTEGER *)&current_time);
	io.DeltaTime = (float)(current_time - g_Time) / g_TicksPerSecond;
	g_Time = current_time;

	// Read keyboard modifiers inputs
	io.KeyCtrl = (GetKeyState(VK_CONTROL) & 0x8000) != 0;
	io.KeyShift = (GetKeyState(VK_SHIFT) & 0x8000) != 0;
	io.KeyAlt = (GetKeyState(VK_MENU) & 0x8000) != 0;
	io.KeySuper = false;
	// io.KeysDown : filled by WM_KEYDOWN/WM_KEYUP events
	// io.MousePos : filled by WM_MOUSEMOVE events
	// io.MouseDown : filled by WM_BUTTON events
	// io.MouseWheel : filled by WM_MOUSEWHEEL events

	// Set OS mouse position if requested (only used when ImGuiConfigFlags_NavEnableSetMousePos is enabled by user)
	if (io.WantSetMousePos)
	{
	POINT pos = { (int)io.MousePos.x, (int)io.MousePos.y };
	ClientToScreen(g_hWnd, &pos);
	SetCursorPos(pos.x, pos.y);
	}

	// Update OS mouse cursor with the cursor requested by imgui
	ImGuiMouseCursor mouse_cursor = io.MouseDrawCursor ? ImGuiMouseCursor_None : ImGui::GetMouseCursor();
	if (g_LastMouseCursor != mouse_cursor)
	{
	g_LastMouseCursor = mouse_cursor;
	ImGui_ImplWin32_UpdateMouseCursor();
	}

	// Start the frame. This call will update the io.WantCaptureMouse, io.WantCaptureKeyboard flag that you can use to dispatch inputs (or not) to your application.
	ImGui::NewFrame();
	}