ImGui DirectX11 Desktop Example

ImGui - GUI-фреймворк, написанный на C++ с минимальными зависимостями. Ссылка на github - https://github.com/ocornut/imgui

Пример программы, использующей ImGui

Это самый обычный пример использования ImGui для desktop-приложения с передвижением окна, можно применять для любых целей.
Для тех, кто сам не может сделать.

#include "Frameworks/ImGui/imgui.h"
#include "Frameworks/ImGui/imgui_impl_win32.h"
#include "Frameworks/ImGui/imgui_impl_dx11.h"
#include <d3d11.h>
#define DIRECTINPUT_VERSION 0x0800
#include <dinput.h>
#include <tchar.h>
#include <string>

#pragma comment(lib, "d3d11.lib")

POINTS m_Pos;

float WindowWidth = 800.0;
float WindowHeight = 600.0;

bool IsOpened = true;

static ID3D11Device* g_pd3dDevice = NULL;
static ID3D11DeviceContext* g_pd3dDeviceContext = NULL;
static IDXGISwapChain* g_pSwapChain = NULL;
static ID3D11RenderTargetView* g_mainRenderTargetView = NULL;

bool CreateDeviceD3D(HWND hWnd);
void CleanupDeviceD3D();
void CreateRenderTarget();
void CleanupRenderTarget();
LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);

int WINAPI WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPSTR lpCmdLine, _In_ int nShowCmd)
{
WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, WndProc, 0L, 0L, GetModuleHandle(NULL), NULL, LoadCursor(NULL, IDC_ARROW), NULL, NULL, _T("ImGui Example"), NULL };
::RegisterClassEx(&wc);
HWND hwnd = ::CreateWindow(wc.lpszClassName, _T("Dear ImGui DirectX11 Example"), WS_POPUP, 0, 0, (int)WindowWidth, (int)WindowHeight, NULL, NULL, wc.hInstance, NULL);

if (!CreateDeviceD3D(hwnd)) {
CleanupDeviceD3D();
::UnregisterClass(wc.lpszClassName, wc.hInstance);
return 1;
}

::ShowWindow(hwnd, SW_SHOWDEFAULT);
::UpdateWindow(hwnd);

IMGUI_CHECKVERSION();
ImGui::CreateContext();
ImGuiIO& io = ImGui::GetIO(); (void)io;

ImGui::StyleColorsDark();

ImGui_ImplWin32_Init(hwnd);
ImGui_ImplDX11_Init(g_pd3dDevice, g_pd3dDeviceContext);

// Load Fonts
// - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.
// - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple.
// - If the file cannot be loaded, the function will return NULL. Please handle those errors in your application (e.g. use an assertion, or display an error and quit).
// - The fonts will be rasterized at a given size (w/ oversampling) and stored into a texture when calling ImFontAtlas::Build()/GetTexDataAsXXXX(), which ImGui_ImplXXXX_NewFrame below will call.
// - Read 'misc/fonts/README.txt' for more instructions and details.
// - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ !
//io.Fonts->AddFontDefault();
//io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f);
//io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f);
//io.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf", 16.0f);
//io.Fonts->AddFontFromFileTTF("../../misc/fonts/ProggyTiny.ttf", 10.0f);
//ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese());
//IM_ASSERT(font != NULL);

MSG msg;
ZeroMemory(&msg, sizeof(msg));
while (msg.message != WM_QUIT)
{
if (::PeekMessage(&msg, NULL, 0U, 0U, PM_REMOVE))
{
::TranslateMessage(&msg);
::DispatchMessage(&msg);
continue;
}

ImGui_ImplDX11_NewFrame();
ImGui_ImplWin32_NewFrame();
ImGui::NewFrame();

ImGui::SetNextWindowPos(ImVec2(0, 0));
ImGui::Begin("ImGui Example", &IsOpened, ImVec2(WindowWidth, WindowHeight), 1.0f, ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoCollapse);
{
static float f = 0.0f;
static int counter = 0;

if (IsOpened == false)
exit(0);

ImGui::Text("This is some useful text.");

if (ImGui::Button("Button"))
counter++;
ImGui::SameLine();
ImGui::Text("counter = %d", counter);

static char str1[128] = "";
ImGui::InputTextWithHint("input text (w/ hint)", "enter text here", str1, IM_ARRAYSIZE(str1));

ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate);
}
ImGui::End();

ImGui::Render();
g_pd3dDeviceContext->OMSetRenderTargets(1, &g_mainRenderTargetView, NULL);
//g_pd3dDeviceContext->ClearRenderTargetView(g_mainRenderTargetView, (float*)& ImVec4(0.00f, 0.00f, 0.00f, 0.00f));
ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());

g_pSwapChain->Present(1, 0);
}

ImGui_ImplDX11_Shutdown();
ImGui_ImplWin32_Shutdown();
ImGui::DestroyContext();

CleanupDeviceD3D();
::DestroyWindow(hwnd);
::UnregisterClass(wc.lpszClassName, wc.hInstance);

return 0;
}

bool CreateDeviceD3D(HWND hWnd)
{
DXGI_SWAP_CHAIN_DESC sd;
ZeroMemory(&sd, sizeof(sd));
sd.BufferCount = 2;
sd.BufferDesc.Width = 0;
sd.BufferDesc.Height = 0;
sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
sd.BufferDesc.RefreshRate.Numerator = 60;
sd.BufferDesc.RefreshRate.Denominator = 1;
sd.Flags = DXGI_SWAP_CHAIN_FLAG_ALLOW_MODE_SWITCH;
sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
sd.OutputWindow = hWnd;
sd.SampleDesc.Count = 1;
sd.SampleDesc.Quality = 0;
sd.Windowed = TRUE;
sd.SwapEffect = DXGI_SWAP_EFFECT_DISCARD;

UINT createDeviceFlags = 0;
D3D_FEATURE_LEVEL featureLevel;
const D3D_FEATURE_LEVEL featureLevelArray[2] = { D3D_FEATURE_LEVEL_11_0, D3D_FEATURE_LEVEL_10_0, };
if (D3D11CreateDeviceAndSwapChain(NULL, D3D_DRIVER_TYPE_HARDWARE, NULL, createDeviceFlags, featureLevelArray, 2, D3D11_SDK_VERSION, &sd, &g_pSwapChain, &g_pd3dDevice, &featureLevel, &g_pd3dDeviceContext) != S_OK)
return false;

CreateRenderTarget();
return true;
}

void CleanupDeviceD3D()
{
CleanupRenderTarget();
if (g_pSwapChain) { g_pSwapChain->Release(); g_pSwapChain = NULL; }
if (g_pd3dDeviceContext) { g_pd3dDeviceContext->Release(); g_pd3dDeviceContext = NULL; }
if (g_pd3dDevice) { g_pd3dDevice->Release(); g_pd3dDevice = NULL; }
}

void CreateRenderTarget()
{
ID3D11Texture2D* pBackBuffer;
g_pSwapChain->GetBuffer(0, IID_PPV_ARGS(&pBackBuffer));
g_pd3dDevice->CreateRenderTargetView(pBackBuffer, NULL, &g_mainRenderTargetView);
pBackBuffer->Release();
}

void CleanupRenderTarget()
{
if (g_mainRenderTargetView) { g_mainRenderTargetView->Release(); g_mainRenderTargetView = NULL; }
}

extern LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
if (ImGui_ImplWin32_WndProcHandler(hWnd, msg, wParam, lParam))
return true;

ImGuiIO& io = ImGui::GetIO();
switch (msg)
{
case WM_LBUTTONDOWN: case WM_LBUTTONDBLCLK:
case WM_RBUTTONDOWN: case WM_RBUTTONDBLCLK:
case WM_MBUTTONDOWN: case WM_MBUTTONDBLCLK:
{
if (msg == WM_LBUTTONDOWN) m_Pos = MAKEPOINTS(lParam);
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_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:
// wchar_t wch;
// MultiByteToWideChar(CP_ACP, MB_PRECOMPOSED, (char*)& wParam, 1, &wch, 1);
// io.AddInputCharacter(wch);
// return 0;
case WM_SETCURSOR:
if (LOWORD(lParam) == HTCLIENT)
{
if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)
return false;

ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();
if (imgui_cursor == ImGuiMouseCursor_None || io.MouseDrawCursor)
{
::SetCursor(NULL);
}
else
{
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;
case ImGuiMouseCursor_Hand: win32_cursor = IDC_HAND; break;
}
::SetCursor(::LoadCursor(NULL, win32_cursor));
}

return 1;
}
return 0;
case WM_DESTROY:
PostQuitMessage(0);
return 0;
case WM_MOUSEMOVE:
{
float TitleHeight = ImGui::GetFontSize() + ImGui::GetStyle().FramePadding.y * 2.0f;
io.MousePos.x = (signed short)(lParam);
io.MousePos.y = (signed short)(lParam >> 16);
if (wParam == MK_LBUTTON)
{
POINTS p = MAKEPOINTS(lParam);
RECT rect;
GetWindowRect(hWnd, &rect);
rect.left += p.x - m_Pos.x;
rect.top += p.y - m_Pos.y;
if ((m_Pos.x >= 0 && m_Pos.x <= WindowWidth && m_Pos.y >= 0 && m_Pos.y <= TitleHeight))
SetWindowPos(hWnd, HWND_TOPMOST, rect.left, rect.top, 0, 0, SWP_SHOWWINDOW | SWP_NOSIZE | SWP_NOZORDER);
}
return 0;
}
}
return DefWindowProc(hWnd, msg, wParam, lParam);
}

Код

#include "Frameworks/ImGui/imgui.h"

#include "Frameworks/ImGui/imgui_impl_win32.h"

#include "Frameworks/ImGui/imgui_impl_dx11.h"

#include <d3d11.h>

#define DIRECTINPUT_VERSION 0x0800

#include <dinput.h>

#include <tchar.h>

#include <string>



#pragma comment(lib, "d3d11.lib")



POINTS m_Pos;



float WindowWidth = 800.0;

float WindowHeight = 600.0;



bool IsOpened = true;



static ID3D11Device* g_pd3dDevice = NULL;

static ID3D11DeviceContext* g_pd3dDeviceContext = NULL;

static IDXGISwapChain* g_pSwapChain = NULL;

static ID3D11RenderTargetView* g_mainRenderTargetView = NULL;



bool CreateDeviceD3D(HWND hWnd);

void CleanupDeviceD3D();

void CreateRenderTarget();

void CleanupRenderTarget();

LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);



int WINAPI WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPSTR lpCmdLine, _In_ int nShowCmd)

{

    WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, WndProc, 0L, 0L, GetModuleHandle(NULL), NULL, LoadCursor(NULL, IDC_ARROW), NULL, NULL, _T("ImGui Example"), NULL };

    ::RegisterClassEx(&wc);

    HWND hwnd = ::CreateWindow(wc.lpszClassName, _T("Dear ImGui DirectX11 Example"), WS_POPUP, 0, 0, (int)WindowWidth, (int)WindowHeight, NULL, NULL, wc.hInstance, NULL);



    if (!CreateDeviceD3D(hwnd)) {

        CleanupDeviceD3D();

        ::UnregisterClass(wc.lpszClassName, wc.hInstance);

        return 1;

    }



    ::ShowWindow(hwnd, SW_SHOWDEFAULT);

    ::UpdateWindow(hwnd);



    IMGUI_CHECKVERSION();

    ImGui::CreateContext();

    ImGuiIO& io = ImGui::GetIO(); (void)io;



    ImGui::StyleColorsDark();



    ImGui_ImplWin32_Init(hwnd);

    ImGui_ImplDX11_Init(g_pd3dDevice, g_pd3dDeviceContext);



    // Load Fonts

    // - If no fonts are loaded, dear imgui will use the default font. You can also load multiple fonts and use ImGui::PushFont()/PopFont() to select them.

    // - AddFontFromFileTTF() will return the ImFont* so you can store it if you need to select the font among multiple.

    // - If the file cannot be loaded, the function will return NULL. Please handle those errors in your application (e.g. use an assertion, or display an error and quit).

    // - The fonts will be rasterized at a given size (w/ oversampling) and stored into a texture when calling ImFontAtlas::Build()/GetTexDataAsXXXX(), which ImGui_ImplXXXX_NewFrame below will call.

    // - Read 'misc/fonts/README.txt' for more instructions and details.

    // - Remember that in C/C++ if you want to include a backslash \ in a string literal you need to write a double backslash \\ !

    //io.Fonts->AddFontDefault();

    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Roboto-Medium.ttf", 16.0f);

    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/Cousine-Regular.ttf", 15.0f);

    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/DroidSans.ttf", 16.0f);

    //io.Fonts->AddFontFromFileTTF("../../misc/fonts/ProggyTiny.ttf", 10.0f);

    //ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese());

    //IM_ASSERT(font != NULL);



    MSG msg;

    ZeroMemory(&msg, sizeof(msg));

    while (msg.message != WM_QUIT)

    {

        if (::PeekMessage(&msg, NULL, 0U, 0U, PM_REMOVE))

        {

            ::TranslateMessage(&msg);

            ::DispatchMessage(&msg);

            continue;

        }



        ImGui_ImplDX11_NewFrame();

        ImGui_ImplWin32_NewFrame();

        ImGui::NewFrame();



        ImGui::SetNextWindowPos(ImVec2(0, 0));

        ImGui::Begin("ImGui Example", &IsOpened, ImVec2(WindowWidth, WindowHeight), 1.0f, ImGuiWindowFlags_NoResize | ImGuiWindowFlags_NoSavedSettings | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoCollapse);

        {

            static float f = 0.0f;

            static int counter = 0;



            if (IsOpened == false)

                exit(0);



            ImGui::Text("This is some useful text.");



            if (ImGui::Button("Button"))

                counter++;

            ImGui::SameLine();

            ImGui::Text("counter = %d", counter);



            static char str1[128] = "";

            ImGui::InputTextWithHint("input text (w/ hint)", "enter text here", str1, IM_ARRAYSIZE(str1));



            ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate);

        }

        ImGui::End();



        ImGui::Render();

        g_pd3dDeviceContext->OMSetRenderTargets(1, &g_mainRenderTargetView, NULL);

        //g_pd3dDeviceContext->ClearRenderTargetView(g_mainRenderTargetView, (float*)& ImVec4(0.00f, 0.00f, 0.00f, 0.00f));

        ImGui_ImplDX11_RenderDrawData(ImGui::GetDrawData());



        g_pSwapChain->Present(1, 0);

    }



    ImGui_ImplDX11_Shutdown();

    ImGui_ImplWin32_Shutdown();

    ImGui::DestroyContext();



    CleanupDeviceD3D();

    ::DestroyWindow(hwnd);

    ::UnregisterClass(wc.lpszClassName, wc.hInstance);



    return 0;

}



bool CreateDeviceD3D(HWND hWnd)

{

    DXGI_SWAP_CHAIN_DESC sd;

    ZeroMemory(&sd, sizeof(sd));

    sd.BufferCount = 2;

    sd.BufferDesc.Width = 0;

    sd.BufferDesc.Height = 0;

    sd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;

    sd.BufferDesc.RefreshRate.Numerator = 60;

    sd.BufferDesc.RefreshRate.Denominator = 1;

    sd.Flags = DXGI_SWAP_CHAIN_FLAG_ALLOW_MODE_SWITCH;

    sd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;

    sd.OutputWindow = hWnd;

    sd.SampleDesc.Count = 1;

    sd.SampleDesc.Quality = 0;

    sd.Windowed = TRUE;

    sd.SwapEffect = DXGI_SWAP_EFFECT_DISCARD;



    UINT createDeviceFlags = 0;

    D3D_FEATURE_LEVEL featureLevel;

    const D3D_FEATURE_LEVEL featureLevelArray[2] = { D3D_FEATURE_LEVEL_11_0, D3D_FEATURE_LEVEL_10_0, };

    if (D3D11CreateDeviceAndSwapChain(NULL, D3D_DRIVER_TYPE_HARDWARE, NULL, createDeviceFlags, featureLevelArray, 2, D3D11_SDK_VERSION, &sd, &g_pSwapChain, &g_pd3dDevice, &featureLevel, &g_pd3dDeviceContext) != S_OK)

        return false;



    CreateRenderTarget();

    return true;

}



void CleanupDeviceD3D()

{

    CleanupRenderTarget();

    if (g_pSwapChain) { g_pSwapChain->Release(); g_pSwapChain = NULL; }

    if (g_pd3dDeviceContext) { g_pd3dDeviceContext->Release(); g_pd3dDeviceContext = NULL; }

    if (g_pd3dDevice) { g_pd3dDevice->Release(); g_pd3dDevice = NULL; }

}



void CreateRenderTarget()

{

    ID3D11Texture2D* pBackBuffer;

    g_pSwapChain->GetBuffer(0, IID_PPV_ARGS(&pBackBuffer));

    g_pd3dDevice->CreateRenderTargetView(pBackBuffer, NULL, &g_mainRenderTargetView);

    pBackBuffer->Release();

}



void CleanupRenderTarget()

{

    if (g_mainRenderTargetView) { g_mainRenderTargetView->Release(); g_mainRenderTargetView = NULL; }

}



extern LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);

LRESULT WINAPI WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)

{

    if (ImGui_ImplWin32_WndProcHandler(hWnd, msg, wParam, lParam))

        return true;



    ImGuiIO& io = ImGui::GetIO();

    switch (msg)

    {

    case WM_LBUTTONDOWN: case WM_LBUTTONDBLCLK:

    case WM_RBUTTONDOWN: case WM_RBUTTONDBLCLK:

    case WM_MBUTTONDOWN: case WM_MBUTTONDBLCLK:

    {

        if (msg == WM_LBUTTONDOWN)  m_Pos = MAKEPOINTS(lParam);

        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_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:

    //    wchar_t wch;

    //    MultiByteToWideChar(CP_ACP, MB_PRECOMPOSED, (char*)& wParam, 1, &wch, 1);

    //    io.AddInputCharacter(wch);

    //    return 0;

    case WM_SETCURSOR:

        if (LOWORD(lParam) == HTCLIENT)

        {

            if (io.ConfigFlags & ImGuiConfigFlags_NoMouseCursorChange)

                return false;



            ImGuiMouseCursor imgui_cursor = ImGui::GetMouseCursor();

            if (imgui_cursor == ImGuiMouseCursor_None || io.MouseDrawCursor)

            {

                ::SetCursor(NULL);

            }

            else

            {

                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;

                case ImGuiMouseCursor_Hand:         win32_cursor = IDC_HAND; break;

                }

                ::SetCursor(::LoadCursor(NULL, win32_cursor));

            }



            return 1;

        }

        return 0;

    case WM_DESTROY:

        PostQuitMessage(0);

        return 0;

    case WM_MOUSEMOVE:

    {

        float TitleHeight = ImGui::GetFontSize() + ImGui::GetStyle().FramePadding.y * 2.0f;

        io.MousePos.x = (signed short)(lParam);

        io.MousePos.y = (signed short)(lParam >> 16);

        if (wParam == MK_LBUTTON)

        {

            POINTS p = MAKEPOINTS(lParam);

            RECT rect;

            GetWindowRect(hWnd, &rect);

            rect.left += p.x - m_Pos.x;

            rect.top += p.y - m_Pos.y;

            if ((m_Pos.x >= 0 && m_Pos.x <= WindowWidth && m_Pos.y >= 0 && m_Pos.y <= TitleHeight))

                SetWindowPos(hWnd, HWND_TOPMOST, rect.left, rect.top, 0, 0, SWP_SHOWWINDOW | SWP_NOSIZE | SWP_NOZORDER);

        }

        return 0;

    }

    }

    return DefWindowProc(hWnd, msg, wParam, lParam);

}

Ссылка на готовый проект - https://yadi.sk/d/qBs0aTbudC4-fA (выставить Release x86 при компиляции)

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