source: Daodan/src/Daodan_WindowHack.c@ 703

#include <windows.h>
#include "Daodan_WindowHack.h"
#include "Daodan_Patch.h"

#include "Oni.h"
#include "Oni_GL.h"

volatile HWND onihwnd, boxhwnd = NULL;
int inclient = 0;
int dragging = 0;

LRESULT CALLBACK DDrHack_WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
        switch (msg)
        {
                case WM_KEYDOWN:
                case WM_ACTIVATE:
                case WM_CHAR:
                case WM_KEYUP:
                        ONrPlatform_WindowProc(onihwnd, msg, wParam, lParam);
                        return DefWindowProc(hwnd, msg, wParam, lParam);
                case WM_SETCURSOR:
                        if (LOWORD(lParam) == HTCLIENT)
                        {
                                if (!inclient)
                                {
                                        inclient = 1;
                                        ShowCursor(FALSE);
                                }
                        }
                        else if (inclient)
                        {
                                inclient = 0;
                                ShowCursor(TRUE);
                        }
                        break;
//              case WM_CLOSE:
//                      CHARTest();
//                      break;
                case WM_DESTROY:
                        PostQuitMessage(0);
                        ExitProcess(0);
                        break;
                case WM_ENTERSIZEMOVE:
                        dragging = 1;
                        break;
                case WM_EXITSIZEMOVE:
                        dragging = 0;
                        break;
                default:
                        return DefWindowProc(hwnd, msg, wParam, lParam);
        }
        return 0;
}

DWORD WINAPI DDrHack_WndMain(LPVOID param)
{
        MSG Msg;
        RECT re;
        WNDCLASSEX wc;
        
        wc.cbSize = sizeof(WNDCLASSEX);
        wc.style = 0;
        wc.lpfnWndProc = DDrHack_WndProc;
        wc.cbClsExtra = 0;
        wc.cbWndExtra = 0;
        wc.hInstance = DDrDLLModule;
        wc.hIcon = LoadIcon(DDrONiModule, MAKEINTRESOURCE(103));
        wc.hCursor = LoadCursor(NULL, IDC_ARROW);
        wc.hbrBackground = CreateSolidBrush(RGB(0, 0, 0));
        wc.lpszMenuName = NULL;
        wc.lpszClassName = "OniGanbatte";
        wc.hIconSm = NULL;
        RegisterClassEx(&wc);
        
        
        re.left = (GetSystemMetrics(SM_CXSCREEN) / 2) - (640 / 2);
        re.top = (GetSystemMetrics(SM_CYSCREEN) / 2) - (480 / 2);
        re.right = re.left + 640;
        re.bottom = re.top + 480;
        AdjustWindowRect(&re, WS_POPUP | (opt_border ? WS_CAPTION | WS_MINIMIZEBOX | WS_SYSMENU : 0), FALSE);
        
        boxhwnd = CreateWindowEx(0, "OniGanbatte", "Oni", WS_POPUP | (opt_border ? WS_CAPTION | WS_MINIMIZEBOX | WS_SYSMENU : 0), re.left, re.top, re.right - re.left, re.bottom - re.top, NULL, NULL, DDrDLLModule, NULL);
        
        while (GetMessage(&Msg, NULL, 0, 0) > 0)
        {
                TranslateMessage(&Msg);
                DispatchMessage(&Msg);
        }
        return 0;
}

HWND WINAPI ONrPI_CreateWindowExHook(DWORD dwExStyle, const char* lpClassName, const char* lpWindowName, DWORD dwStyle, int x, int y, int nWidth, int nHeight, HWND hWndParent, HMENU hMenu, HINSTANCE hInstance, LPVOID lpParam)
{
        CloseHandle(CreateThread(NULL, 0, DDrHack_WndMain, NULL, 0, NULL));
        
        while (!boxhwnd)
                Sleep(50);
        
        onihwnd = CreateWindowExA(dwExStyle, lpClassName, lpWindowName, WS_POPUP | WS_VISIBLE, 0, 0, 640, 480, boxhwnd, hMenu, hInstance, lpParam);
        SetParent(onihwnd, boxhwnd);
        return onihwnd;
}

BOOL WINAPI glpi_SetWindowPosHook(HWND hWnd, HWND hWndInsertAfter, int X, int Y, int cx, int cy, UINT uFlags)
{
        RECT re;
        SetWindowLong(onihwnd, GWL_STYLE, WS_CHILD | WS_VISIBLE);
        SetCursor(LoadCursor(NULL, IDC_ARROW));
        
        
        re.left = (GetSystemMetrics(SM_CXSCREEN) / 2) - (cx / 2);
        re.top = (GetSystemMetrics(SM_CYSCREEN) / 2) - (cy / 2);
        re.right = re.left + cx;
        re.bottom = re.top + cy;
        AdjustWindowRect(&re, WS_POPUP | (opt_border ? WS_CAPTION | WS_MINIMIZEBOX | WS_SYSMENU : 0), FALSE);
        
        SetWindowPos(boxhwnd, opt_topmost ? HWND_TOPMOST : NULL, re.left, re.top, re.right - re.left, re.bottom - re.top, (opt_topmost ? uFlags & ~SWP_NOZORDER : uFlags | SWP_NOOWNERZORDER));
        ShowWindow(boxhwnd, SW_SHOW);
        UpdateWindow(boxhwnd);
        return SetWindowPos(hWnd, NULL, 0, 0, cx, cy, uFlags | SWP_NOOWNERZORDER);
}

BOOL WINAPI LIiP_GetCursorPosHook(LPPOINT lpPoint)
{
        if (GetAsyncKeyState(VK_F4) || dragging)
        {
                lpPoint->x = gl_eng->DisplayMode.Width / 2;
                lpPoint->y = gl_eng->DisplayMode.Height / 2;
        }
        else
        {
                if (!GetCursorPos(lpPoint))
                        return 0;
                if (onihwnd != NULL)
                        ScreenToClient(onihwnd, lpPoint);
        }
        return 1;
}

BOOL WINAPI LIiP_SetCursorPosHook(int X, int Y)
{
        if (GetAsyncKeyState(VK_F4) || dragging)
                return TRUE;
        else
        {
                POINT pt;
                pt.x = X;
                pt.y = Y;
                if (onihwnd != NULL)
                        ClientToScreen(onihwnd, &pt);
                return SetCursorPos(pt.x, pt.y);
        }
}

void DDrWindowHack_Install()
{
        DDrPatch_NOOP((char*)0x0050F764, 6);
        DDrPatch_MakeCall((char*)0x0050F764, (void*)ONrPI_CreateWindowExHook);
        
        DDrPatch_NOOP((char*)0x00407E9F, 6);
        DDrPatch_MakeCall((char*)0x00407E9F, (void*)glpi_SetWindowPosHook);
        
        DDrPatch_NOOP((char*)0x004032CC, 6);
        DDrPatch_MakeCall((char*)0x004032CC, (void*)LIiP_GetCursorPosHook);
        
        DDrPatch_NOOP((char*)0x00402CC2, 6);
        DDrPatch_MakeCall((char*)0x00402CC2, (void*)LIiP_GetCursorPosHook);
        
        DDrPatch_NOOP((char*)0x004032B7, 6);
        DDrPatch_MakeCall((char*)0x004032B7, (void*)LIiP_SetCursorPosHook);
        
        DDrPatch_NOOP((char*)0x00403349, 6);
        DDrPatch_MakeCall((char*)0x00403349, (void*)LIiP_SetCursorPosHook);
}