Seaside/SpyCustom/imgui/imgui_impl_win32.cpp

#include "imgui.h"
#include "imgui_impl_win32.h"
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#include <tchar.h>

#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
#include <XInput.h>
typedef DWORD (WINAPI *PFN_XInputGetCapabilities)(DWORD, DWORD, XINPUT_CAPABILITIES*);
typedef DWORD (WINAPI *PFN_XInputGetState)(DWORD, XINPUT_STATE*);
#endif

static HWND                 g_hWnd = NULL;
static INT64                g_Time = 0;
static INT64                g_TicksPerSecond = 0;
static ImGuiMouseCursor     g_LastMouseCursor = ImGuiMouseCursor_COUNT;
static bool                 g_HasGamepad = false;
static bool                 g_WantUpdateHasGamepad = true;

#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
static HMODULE                      g_XInputDLL = NULL;
static PFN_XInputGetCapabilities    g_XInputGetCapabilities = NULL;
static PFN_XInputGetState           g_XInputGetState = NULL;
#endif

bool    ImGui_ImplWin32_Init(void* hwnd)
{
    if (!::QueryPerformanceFrequency((LARGE_INTEGER*)&g_TicksPerSecond))
        return false;
    if (!::QueryPerformanceCounter((LARGE_INTEGER*)&g_Time))
        return false;

    g_hWnd = (HWND)hwnd;
    ImGuiIO& io = ImGui::GetIO();
    io.BackendFlags |= ImGuiBackendFlags_HasMouseCursors;               
    io.BackendFlags |= ImGuiBackendFlags_HasSetMousePos;                  
    io.BackendPlatformName = "imgui_impl_win32";
    io.ImeWindowHandle = hwnd;

    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_KeyPadEnter] = VK_RETURN;
    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';

#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
    const char* xinput_dll_names[] =
    {
        "xinput1_4.dll",     
        "xinput1_3.dll",     
        "xinput9_1_0.dll",     
        "xinput1_2.dll",     
        "xinput1_1.dll"      
    };
    for (int n = 0; n < IM_ARRAYSIZE(xinput_dll_names); n++)
        if (HMODULE dll = ::LoadLibraryA(xinput_dll_names[n]))
        {
            g_XInputDLL = dll;
            g_XInputGetCapabilities = (PFN_XInputGetCapabilities)::GetProcAddress(dll, "XInputGetCapabilities");
            g_XInputGetState = (PFN_XInputGetState)::GetProcAddress(dll, "XInputGetState");
            break;
        }
#endif  
    
    return true;
}

void    ImGui_ImplWin32_Shutdown()
{
#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
    if (g_XInputDLL)
        ::FreeLibrary(g_XInputDLL);
    g_XInputDLL = NULL;
    g_XInputGetCapabilities = NULL;
    g_XInputGetState = NULL;
#endif  
    
    g_hWnd = NULL;
    g_Time = 0;
    g_TicksPerSecond = 0;
    g_LastMouseCursor = ImGuiMouseCursor_COUNT;
    g_HasGamepad = false;
    g_WantUpdateHasGamepad = true;
}

static bool ImGui_ImplWin32_UpdateMouseCursor()
{
    ImGuiIO& io = ImGui::GetIO();
    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;
        case ImGuiMouseCursor_NotAllowed:   win32_cursor = IDC_NO; break;
        }
        ::SetCursor(::LoadCursor(NULL, win32_cursor));
    }
    return true;
}

static void ImGui_ImplWin32_UpdateMousePos()
{
    ImGuiIO& io = ImGui::GetIO();

    if (io.WantSetMousePos)
    {
        POINT pos = { (int)io.MousePos.x, (int)io.MousePos.y };
        if (::ClientToScreen(g_hWnd, &pos))
            ::SetCursorPos(pos.x, pos.y);
    }

    io.MousePos = ImVec2(-FLT_MAX, -FLT_MAX);
    POINT pos;
    if (HWND active_window = ::GetForegroundWindow())
        if (active_window == g_hWnd || ::IsChild(active_window, g_hWnd))
            if (::GetCursorPos(&pos) && ::ScreenToClient(g_hWnd, &pos))
                io.MousePos = ImVec2((float)pos.x, (float)pos.y);
}

static void ImGui_ImplWin32_UpdateGamepads()
{
#ifndef IMGUI_IMPL_WIN32_DISABLE_GAMEPAD
    ImGuiIO& io = ImGui::GetIO();
    memset(io.NavInputs, 0, sizeof(io.NavInputs));
    if ((io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) == 0)
        return;

    if (g_WantUpdateHasGamepad)
    {
        XINPUT_CAPABILITIES caps;
        g_HasGamepad = g_XInputGetCapabilities ? (g_XInputGetCapabilities(0, XINPUT_FLAG_GAMEPAD, &caps) == ERROR_SUCCESS) : false;
        g_WantUpdateHasGamepad = false;
    }

    io.BackendFlags &= ~ImGuiBackendFlags_HasGamepad;
    XINPUT_STATE xinput_state;
    if (g_HasGamepad && g_XInputGetState && g_XInputGetState(0, &xinput_state) == ERROR_SUCCESS)
    {
        const XINPUT_GAMEPAD& gamepad = xinput_state.Gamepad;
        io.BackendFlags |= ImGuiBackendFlags_HasGamepad;

        #define MAP_BUTTON(NAV_NO, BUTTON_ENUM)     { io.NavInputs[NAV_NO] = (gamepad.wButtons & BUTTON_ENUM) ? 1.0f : 0.0f; }
        #define MAP_ANALOG(NAV_NO, VALUE, V0, V1)   { float vn = (float)(VALUE - V0) / (float)(V1 - V0); if (vn > 1.0f) vn = 1.0f; if (vn > 0.0f && io.NavInputs[NAV_NO] < vn) io.NavInputs[NAV_NO] = vn; }
        MAP_BUTTON(ImGuiNavInput_Activate,      XINPUT_GAMEPAD_A);                 
        MAP_BUTTON(ImGuiNavInput_Cancel,        XINPUT_GAMEPAD_B);                 
        MAP_BUTTON(ImGuiNavInput_Menu,          XINPUT_GAMEPAD_X);                 
        MAP_BUTTON(ImGuiNavInput_Input,         XINPUT_GAMEPAD_Y);                 
        MAP_BUTTON(ImGuiNavInput_DpadLeft,      XINPUT_GAMEPAD_DPAD_LEFT);        
        MAP_BUTTON(ImGuiNavInput_DpadRight,     XINPUT_GAMEPAD_DPAD_RIGHT);       
        MAP_BUTTON(ImGuiNavInput_DpadUp,        XINPUT_GAMEPAD_DPAD_UP);          
        MAP_BUTTON(ImGuiNavInput_DpadDown,      XINPUT_GAMEPAD_DPAD_DOWN);        
        MAP_BUTTON(ImGuiNavInput_FocusPrev,     XINPUT_GAMEPAD_LEFT_SHOULDER);     
        MAP_BUTTON(ImGuiNavInput_FocusNext,     XINPUT_GAMEPAD_RIGHT_SHOULDER);    
        MAP_BUTTON(ImGuiNavInput_TweakSlow,     XINPUT_GAMEPAD_LEFT_SHOULDER);     
        MAP_BUTTON(ImGuiNavInput_TweakFast,     XINPUT_GAMEPAD_RIGHT_SHOULDER);    
        MAP_ANALOG(ImGuiNavInput_LStickLeft,    gamepad.sThumbLX,  -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, -32768);
        MAP_ANALOG(ImGuiNavInput_LStickRight,   gamepad.sThumbLX,  +XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, +32767);
        MAP_ANALOG(ImGuiNavInput_LStickUp,      gamepad.sThumbLY,  +XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, +32767);
        MAP_ANALOG(ImGuiNavInput_LStickDown,    gamepad.sThumbLY,  -XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE, -32767);
        #undef MAP_BUTTON
        #undef MAP_ANALOG
    }
#endif   
}

void    ImGui_ImplWin32_NewFrame()
{
    ImGuiIO& io = ImGui::GetIO();
    IM_ASSERT(io.Fonts->IsBuilt() && "Font atlas not built! It is generally built by the renderer backend. Missing call to renderer _NewFrame() function? e.g. ImGui_ImplOpenGL3_NewFrame().");

    RECT rect = { 0, 0, 0, 0 };
    ::GetClientRect(g_hWnd, &rect);
    io.DisplaySize = ImVec2((float)(rect.right - rect.left), (float)(rect.bottom - rect.top));

    INT64 current_time = 0;
    ::QueryPerformanceCounter((LARGE_INTEGER*)&current_time);
    io.DeltaTime = (float)(current_time - g_Time) / g_TicksPerSecond;
    g_Time = current_time;

    io.KeyCtrl = (::GetKeyState(VK_CONTROL) & 0x8000) != 0;
    io.KeyShift = (::GetKeyState(VK_SHIFT) & 0x8000) != 0;
    io.KeyAlt = (::GetKeyState(VK_MENU) & 0x8000) != 0;
    io.KeySuper = false;
    ImGui_ImplWin32_UpdateMousePos();

    ImGuiMouseCursor mouse_cursor = io.MouseDrawCursor ? ImGuiMouseCursor_None : ImGui::GetMouseCursor();
    if (g_LastMouseCursor != mouse_cursor)
    {
        g_LastMouseCursor = mouse_cursor;
        ImGui_ImplWin32_UpdateMouseCursor();
    }

    ImGui_ImplWin32_UpdateGamepads();
}

#ifndef WM_MOUSEHWHEEL
#define WM_MOUSEHWHEEL 0x020E
#endif
#ifndef DBT_DEVNODES_CHANGED
#define DBT_DEVNODES_CHANGED 0x0007
#endif

#if 0
extern IMGUI_IMPL_API LRESULT ImGui_ImplWin32_WndProcHandler(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
#endif
IMGUI_IMPL_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:
    case WM_XBUTTONDOWN: case WM_XBUTTONDBLCLK:
    {
        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 (msg == WM_XBUTTONDOWN || msg == WM_XBUTTONDBLCLK) { button = (GET_XBUTTON_WPARAM(wParam) == XBUTTON1) ? 3 : 4; }
        if (!ImGui::IsAnyMouseDown() && ::GetCapture() == NULL)
            ::SetCapture(hwnd);
        io.MouseDown[button] = true;
        return 0;
    }
    case WM_LBUTTONUP:
    case WM_RBUTTONUP:
    case WM_MBUTTONUP:
    case WM_XBUTTONUP:
    {
        int button = 0;
        if (msg == WM_LBUTTONUP) { button = 0; }
        if (msg == WM_RBUTTONUP) { button = 1; }
        if (msg == WM_MBUTTONUP) { button = 2; }
        if (msg == WM_XBUTTONUP) { button = (GET_XBUTTON_WPARAM(wParam) == XBUTTON1) ? 3 : 4; }
        io.MouseDown[button] = false;
        if (!ImGui::IsAnyMouseDown() && ::GetCapture() == hwnd)
            ::ReleaseCapture();
        return 0;
    }
    case WM_MOUSEWHEEL:
        io.MouseWheel += (float)GET_WHEEL_DELTA_WPARAM(wParam) / (float)WHEEL_DELTA;
        return 0;
    case WM_MOUSEHWHEEL:
        io.MouseWheelH += (float)GET_WHEEL_DELTA_WPARAM(wParam) / (float)WHEEL_DELTA;
        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:
        if (wParam > 0 && wParam < 0x10000)
            io.AddInputCharacterUTF16((unsigned short)wParam);
        return 0;
    case WM_SETCURSOR:
        if (LOWORD(lParam) == HTCLIENT && ImGui_ImplWin32_UpdateMouseCursor())
            return 1;
        return 0;
    case WM_DEVICECHANGE:
        if ((UINT)wParam == DBT_DEVNODES_CHANGED)
            g_WantUpdateHasGamepad = true;
        return 0;
    }
    return 0;
}


#if !defined(_versionhelpers_H_INCLUDED_) && !defined(_INC_VERSIONHELPERS)
static BOOL IsWindowsVersionOrGreater(WORD major, WORD minor, WORD sp)
{
    OSVERSIONINFOEXW osvi = { sizeof(osvi), major, minor, 0, 0, { 0 }, sp, 0, 0, 0, 0 };
    DWORD mask = VER_MAJORVERSION | VER_MINORVERSION | VER_SERVICEPACKMAJOR;
    ULONGLONG cond = ::VerSetConditionMask(0, VER_MAJORVERSION, VER_GREATER_EQUAL);
    cond = ::VerSetConditionMask(cond, VER_MINORVERSION, VER_GREATER_EQUAL);
    cond = ::VerSetConditionMask(cond, VER_SERVICEPACKMAJOR, VER_GREATER_EQUAL);
    return ::VerifyVersionInfoW(&osvi, mask, cond);
}
#define IsWindows8Point1OrGreater()  IsWindowsVersionOrGreater(HIBYTE(0x0602), LOBYTE(0x0602), 0)  
#endif

#ifndef DPI_ENUMS_DECLARED
typedef enum { PROCESS_DPI_UNAWARE = 0, PROCESS_SYSTEM_DPI_AWARE = 1, PROCESS_PER_MONITOR_DPI_AWARE = 2 } PROCESS_DPI_AWARENESS;
typedef enum { MDT_EFFECTIVE_DPI = 0, MDT_ANGULAR_DPI = 1, MDT_RAW_DPI = 2, MDT_DEFAULT = MDT_EFFECTIVE_DPI } MONITOR_DPI_TYPE;
#endif
#ifndef _DPI_AWARENESS_CONTEXTS_
DECLARE_HANDLE(DPI_AWARENESS_CONTEXT);
#define DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE    (DPI_AWARENESS_CONTEXT)-3
#endif
#ifndef DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2
#define DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2 (DPI_AWARENESS_CONTEXT)-4
#endif
typedef HRESULT(WINAPI* PFN_SetProcessDpiAwareness)(PROCESS_DPI_AWARENESS);                          
typedef HRESULT(WINAPI* PFN_GetDpiForMonitor)(HMONITOR, MONITOR_DPI_TYPE, UINT*, UINT*);             
typedef DPI_AWARENESS_CONTEXT(WINAPI* PFN_SetThreadDpiAwarenessContext)(DPI_AWARENESS_CONTEXT);         

void ImGui_ImplWin32_EnableDpiAwareness()
{
    {
        static HINSTANCE user32_dll = ::LoadLibraryA("user32.dll");    
        if (PFN_SetThreadDpiAwarenessContext SetThreadDpiAwarenessContextFn = (PFN_SetThreadDpiAwarenessContext)::GetProcAddress(user32_dll, "SetThreadDpiAwarenessContext"))
        {
            SetThreadDpiAwarenessContextFn(DPI_AWARENESS_CONTEXT_PER_MONITOR_AWARE_V2);
            return;
        }
    }
    if (IsWindows8Point1OrGreater())
    {
        static HINSTANCE shcore_dll = ::LoadLibraryA("shcore.dll");    
        if (PFN_SetProcessDpiAwareness SetProcessDpiAwarenessFn = (PFN_SetProcessDpiAwareness)::GetProcAddress(shcore_dll, "SetProcessDpiAwareness"))
        {
            SetProcessDpiAwarenessFn(PROCESS_PER_MONITOR_DPI_AWARE);
            return;
        }
    }
#if _WIN32_WINNT >= 0x0600
    ::SetProcessDPIAware();
#endif
}

#if defined(_MSC_VER) && !defined(NOGDI)
#pragma comment(lib, "gdi32")        
#endif

float ImGui_ImplWin32_GetDpiScaleForMonitor(void* monitor)
{
    UINT xdpi = 96, ydpi = 96;
    static BOOL bIsWindows8Point1OrGreater = IsWindows8Point1OrGreater();
    if (bIsWindows8Point1OrGreater)
    {
        static HINSTANCE shcore_dll = ::LoadLibraryA("shcore.dll");    
        if (PFN_GetDpiForMonitor GetDpiForMonitorFn = (PFN_GetDpiForMonitor)::GetProcAddress(shcore_dll, "GetDpiForMonitor"))
            GetDpiForMonitorFn((HMONITOR)monitor, MDT_EFFECTIVE_DPI, &xdpi, &ydpi);
    }
#ifndef NOGDI
    else
    {
        const HDC dc = ::GetDC(NULL);
        xdpi = ::GetDeviceCaps(dc, LOGPIXELSX);
        ydpi = ::GetDeviceCaps(dc, LOGPIXELSY);
        ::ReleaseDC(NULL, dc);
    }
#endif
    IM_ASSERT(xdpi == ydpi);         
    return xdpi / 96.0f;
}

float ImGui_ImplWin32_GetDpiScaleForHwnd(void* hwnd)
{
    HMONITOR monitor = ::MonitorFromWindow((HWND)hwnd, MONITOR_DEFAULTTONEAREST);
    return ImGui_ImplWin32_GetDpiScaleForMonitor(monitor);
}