view src/video/win32/SDL_win32window.c @ 3168:6338b7f2d024

Hi, I have prepared a set of patches to readd WindowsCE support to SDL 1.3. I've created a new GAPI/Rawframebuffer and a DirectDraw renderer. Both renderers are work in progress and there are several unimplemented cases. (Notably RenderLine/RenderPoint/RenderFill/QueryTexturePixels/UpdateTexture and texture blending ) Nevertheless I am successfully using these renderers together with the SDL software renderer. (On most devices the SDL software renderer will be much faster as there are only badly optimized vendor drivers available) I send these patches now in this unpolished state because there seems to be some interest in win ce and someone has to start supporting SDL 1.3 Now on to the patches: wince_events_window_fixes.patch fixes some wince incompatibilities and adds fullscreen support via SHFullScreen. NOTE: This patch shouldn't have any side effects on Windows, but I have NOT tested it on Windows, so please double-check. This patch doesn't dependent on the following ones. wince_renderers_system.patch This patch does all necessary modifications to the SDL system. - it adds the renderers to the configure system - it adds the renderers to win32video SDL_ceddrawrender.c SDL_ceddrawrender.h SDL_gapirender_c.h SDL_gapirender.c SDL_gapirender.h these files add the new render drivers and should be placed in src/video/win32 Some notes to people who want to test this: - I have only compiled sdl with ming32ce, so the VisualC files are not up to date - As mingw32ce has no ddraw.h this file must be taken from the MS SDK and modified to work with gcc - I had to modify line 2611 in configure.in to EXTRA_LDFLAGS="$EXTRA_LDFLAGS -lcoredll -lcommctrl -lmmtimer -Wl,--image-base -Wl,0x10000" otherwise GetCPinfo wouldn't link. If someone knows whats causing this I'd be happy to hear about it. It would be great if these patches could make their way into SVN as this would make collaboration much much easier. I'm out of office for the next week and therefore will be unavailable via email. Regards Stefan
author Sam Lantinga <slouken@libsdl.org>
date Sun, 07 Jun 2009 02:44:46 +0000
parents 7f684f249ec9
children 413672b09bb3
line wrap: on
line source

/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/

/* we need to define it, so that raw input is included */

#if (_WIN32_WINNT < 0x0501)
#undef _WIN32_WINNT
#define _WIN32_WINNT 0x0501
#endif

#include "SDL_config.h"

#include "../SDL_sysvideo.h"
#include "../SDL_pixels_c.h"
#include "../../events/SDL_keyboard_c.h"

#include "SDL_win32video.h"

/* This is included after SDL_win32video.h, which includes windows.h */
#include "SDL_syswm.h"


#define SHFS_SHOWTASKBAR            0x0001
#define SHFS_HIDETASKBAR            0x0002
#define SHFS_SHOWSIPBUTTON          0x0004
#define SHFS_HIDESIPBUTTON          0x0008
#define SHFS_SHOWSTARTICON          0x0010
#define SHFS_HIDESTARTICON          0x0020

#ifdef _WIN32_WCE
// dynamically load aygshell dll because we want SDL to work on HPC and be300
int aygshell_loaded = 0;
BOOL(WINAPI * SHFullScreen) (HWND hwndRequester, DWORD dwState) = 0;


static BOOL
CE_SHFullScreen(HWND hwndRequester, DWORD dwState)
{
    if (SHFullScreen == 0 && aygshell_loaded == 0) {
        aygshell_loaded = 0;
        void *lib = SDL_LoadObject("aygshell.dll");
        if (lib) {
            SHFullScreen =
                (BOOL(WINAPI *) (HWND, DWORD)) SDL_LoadFunction(lib,
                                                                "SHFullScreen");
        }
    }

    if (SHFullScreen) {
        SHFullScreen(hwndRequester, dwState);
        //printf("SHFullscreen(%i)\n",dwState);
    }
}

#endif

extern HCTX *g_hCtx;            /* the table of tablet event contexts, each windows has to have it's own tablet context */
static Uint32 highestId = 0;    /* the highest id of the tablet context */

/* Fake window to help with DirectInput events. */
HWND SDL_HelperWindow = NULL;
static WCHAR *SDL_HelperWindowClassName = TEXT("SDLHelperWindowInputCatcher");
static WCHAR *SDL_HelperWindowName = TEXT("SDLHelperWindowInputMsgWindow");
static ATOM SDL_HelperWindowClass = 0;

static int
SetupWindowData(_THIS, SDL_Window * window, HWND hwnd, SDL_bool created)
{
    SDL_VideoData *videodata = (SDL_VideoData *) _this->driverdata;
    SDL_WindowData *data;

    /* Allocate the window data */
    data = (SDL_WindowData *) SDL_malloc(sizeof(*data));
    if (!data) {
        SDL_OutOfMemory();
        return -1;
    }
    data->windowID = window->id;
    data->hwnd = hwnd;
    data->hdc = GetDC(hwnd);
    data->created = created;
    data->mouse_pressed = SDL_FALSE;
    data->videodata = videodata;

    /* Associate the data with the window */
    if (!SetProp(hwnd, TEXT("SDL_WindowData"), data)) {
        ReleaseDC(hwnd, data->hdc);
        SDL_free(data);
        WIN_SetError("SetProp() failed");
        return -1;
    }

    /* Set up the window proc function */
    data->wndproc = (WNDPROC) GetWindowLongPtr(hwnd, GWLP_WNDPROC);
    if (data->wndproc == NULL) {
        data->wndproc = DefWindowProc;
    } else {
        SetWindowLongPtr(hwnd, GWLP_WNDPROC, (LONG_PTR) WIN_WindowProc);
    }

    /* Fill in the SDL window with the window data */
    {
        POINT point;
        point.x = 0;
        point.y = 0;
        if (ClientToScreen(hwnd, &point)) {
            window->x = point.x;
            window->y = point.y;
        }
    }
    {
        RECT rect;
        if (GetClientRect(hwnd, &rect)) {
            window->w = rect.right;
            window->h = rect.bottom;
        }
    }
    {
        DWORD style = GetWindowLong(hwnd, GWL_STYLE);
        if (style & WS_VISIBLE) {
            window->flags |= SDL_WINDOW_SHOWN;
        } else {
            window->flags &= ~SDL_WINDOW_SHOWN;
        }
        if (style & (WS_BORDER | WS_THICKFRAME)) {
            window->flags &= ~SDL_WINDOW_BORDERLESS;
        } else {
            window->flags |= SDL_WINDOW_BORDERLESS;
        }
        if (style & WS_THICKFRAME) {
            window->flags |= SDL_WINDOW_RESIZABLE;
        } else {
            window->flags &= ~SDL_WINDOW_RESIZABLE;
        }
        if (style & WS_MAXIMIZE) {
            window->flags |= SDL_WINDOW_MAXIMIZED;
        } else {
            window->flags &= ~SDL_WINDOW_MAXIMIZED;
        }
        if (style & WS_MINIMIZE) {
            window->flags |= SDL_WINDOW_MINIMIZED;
        } else {
            window->flags &= ~SDL_WINDOW_MINIMIZED;
        }
    }
    if (GetFocus() == hwnd) {
        int index = data->videodata->keyboard;
        window->flags |= SDL_WINDOW_INPUT_FOCUS;
        SDL_SetKeyboardFocus(index, data->windowID);

        if (window->flags & SDL_WINDOW_INPUT_GRABBED) {
            RECT rect;
            GetClientRect(hwnd, &rect);
            ClientToScreen(hwnd, (LPPOINT) & rect);
            ClientToScreen(hwnd, (LPPOINT) & rect + 1);
            ClipCursor(&rect);
        }
    }

    /* All done! */
    window->driverdata = data;
    return 0;
}

int
WIN_CreateWindow(_THIS, SDL_Window * window)
{
    SDL_VideoData *videodata = (SDL_VideoData *) _this->driverdata;
    RAWINPUTDEVICE Rid;
    AXIS TabX, TabY;
    LOGCONTEXTA lc;
    HWND hwnd;
    HWND top;
    RECT rect;
    DWORD style = (WS_CLIPSIBLINGS | WS_CLIPCHILDREN);
    int x, y;
    int w, h;

    if (window->flags & (SDL_WINDOW_BORDERLESS | SDL_WINDOW_FULLSCREEN)) {
        style |= WS_POPUP;
    } else {
        style |= (WS_OVERLAPPED | WS_CAPTION | WS_SYSMENU | WS_MINIMIZEBOX);
    }
    if ((window->flags & SDL_WINDOW_RESIZABLE)
        && !(window->flags & SDL_WINDOW_FULLSCREEN)) {
        style |= (WS_THICKFRAME | WS_MAXIMIZEBOX);
    }

    /* Figure out what the window area will be */
    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        top = HWND_TOPMOST;
    } else {
        top = HWND_NOTOPMOST;
    }
    rect.left = 0;
    rect.top = 0;
    rect.right = window->w;
    rect.bottom = window->h;
    AdjustWindowRectEx(&rect, style, FALSE, 0);
    w = (rect.right - rect.left);
    h = (rect.bottom - rect.top);

    if ((window->flags & SDL_WINDOW_FULLSCREEN)
        || window->x == SDL_WINDOWPOS_CENTERED) {
        x = (GetSystemMetrics(SM_CXSCREEN) - w) / 2;
    } else if (window->x == SDL_WINDOWPOS_UNDEFINED) {
        x = CW_USEDEFAULT;
    } else {
        x = window->x + rect.left;
    }
    if ((window->flags & SDL_WINDOW_FULLSCREEN)
        || window->y == SDL_WINDOWPOS_CENTERED) {
        y = (GetSystemMetrics(SM_CYSCREEN) - h) / 2;
    } else if (window->y == SDL_WINDOWPOS_UNDEFINED) {
        y = CW_USEDEFAULT;
    } else {
        y = window->y + rect.top;
    }

    hwnd =
        CreateWindow(SDL_Appname, TEXT(""), style, x, y, w, h, NULL, NULL,
                     SDL_Instance, NULL);
    if (!hwnd) {
        WIN_SetError("Couldn't create window");
        return -1;
    }

    /* we're configuring the tablet data. See Wintab reference for more info */
    if (videodata->wintabDLL
        && videodata->WTInfoA(WTI_DEFSYSCTX, 0, &lc) != 0) {
        lc.lcPktData = PACKETDATA;
        lc.lcPktMode = PACKETMODE;
        lc.lcOptions |= CXO_MESSAGES;
        lc.lcOptions |= CXO_SYSTEM;
        lc.lcMoveMask = PACKETDATA;
        lc.lcBtnDnMask = lc.lcBtnUpMask = PACKETDATA;
        videodata->WTInfoA(WTI_DEVICES, DVC_X, &TabX);
        videodata->WTInfoA(WTI_DEVICES, DVC_Y, &TabY);
        lc.lcInOrgX = 0;
        lc.lcInOrgY = 0;
        lc.lcInExtX = TabX.axMax;
        lc.lcInExtY = TabY.axMax;
        lc.lcOutOrgX = 0;
        lc.lcOutOrgY = 0;
        lc.lcOutExtX = GetSystemMetrics(SM_CXSCREEN);
        lc.lcOutExtY = -GetSystemMetrics(SM_CYSCREEN);
        if (window->id > highestId) {
            HCTX *tmp_hctx;
            highestId = window->id;
            tmp_hctx =
                (HCTX *) SDL_realloc(g_hCtx, (highestId + 1) * sizeof(HCTX));
            if (!tmp_hctx) {
                SDL_OutOfMemory();
                DestroyWindow(hwnd);
                return -1;
            }
            g_hCtx = tmp_hctx;
        }
        g_hCtx[window->id] = videodata->WTOpenA(hwnd, &lc, TRUE);
    }
#ifndef _WIN32_WCE              /* has no RawInput */
    /* we're telling the window, we want it to report raw input events from mice */
    Rid.usUsagePage = 0x01;
    Rid.usUsage = 0x02;
    Rid.dwFlags = RIDEV_INPUTSINK;
    Rid.hwndTarget = hwnd;
    RegisterRawInputDevices(&Rid, 1, sizeof(Rid));
#endif

    WIN_PumpEvents(_this);

    if (SetupWindowData(_this, window, hwnd, SDL_TRUE) < 0) {
        DestroyWindow(hwnd);
        return -1;
    }
#ifdef SDL_VIDEO_OPENGL_WGL
    if (window->flags & SDL_WINDOW_OPENGL) {
        if (WIN_GL_SetupWindow(_this, window) < 0) {
            WIN_DestroyWindow(_this, window);
            return -1;
        }
    }
#endif
    return 0;
}

int
WIN_CreateWindowFrom(_THIS, SDL_Window * window, const void *data)
{
    HWND hwnd = (HWND) data;
    LPTSTR title;
    int titleLen;

    /* Query the title from the existing window */
    titleLen = GetWindowTextLength(hwnd);
    title = SDL_stack_alloc(TCHAR, titleLen + 1);
    if (title) {
        titleLen = GetWindowText(hwnd, title, titleLen);
    } else {
        titleLen = 0;
    }
    if (titleLen > 0) {
        window->title = WIN_StringToUTF8(title);
    }
    if (title) {
        SDL_stack_free(title);
    }

    if (SetupWindowData(_this, window, hwnd, SDL_FALSE) < 0) {
        return -1;
    }
    return 0;
}

void
WIN_SetWindowTitle(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;
    LPTSTR title;

    if (window->title) {
        title = WIN_UTF8ToString(window->title);
    } else {
        title = NULL;
    }
    SetWindowText(hwnd, title ? title : TEXT(""));
    if (title) {
        SDL_free(title);
    }
}

void
WIN_SetWindowIcon(_THIS, SDL_Window * window, SDL_Surface * icon)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;
    HICON hicon = NULL;

    if (icon) {
        BYTE *icon_bmp;
        int icon_len;
        SDL_RWops *dst;
        SDL_PixelFormat format;
        SDL_Surface *surface;

        /* Create temporary bitmap buffer */
        icon_len = 40 + icon->h * icon->w * 4;
        icon_bmp = SDL_stack_alloc(BYTE, icon_len);
        dst = SDL_RWFromMem(icon_bmp, icon_len);
        if (!dst) {
            SDL_stack_free(icon_bmp);
            return;
        }

        /* Write the BITMAPINFO header */
        SDL_WriteLE32(dst, 40);
        SDL_WriteLE32(dst, icon->w);
        SDL_WriteLE32(dst, icon->h * 2);
        SDL_WriteLE16(dst, 1);
        SDL_WriteLE16(dst, 32);
        SDL_WriteLE32(dst, BI_RGB);
        SDL_WriteLE32(dst, icon->h * icon->w * 4);
        SDL_WriteLE32(dst, 0);
        SDL_WriteLE32(dst, 0);
        SDL_WriteLE32(dst, 0);
        SDL_WriteLE32(dst, 0);

        /* Convert the icon to a 32-bit surface with alpha channel */
        SDL_InitFormat(&format, 32,
                       0x00FF0000, 0x0000FF00, 0x000000FF, 0xFF000000);
        surface = SDL_ConvertSurface(icon, &format, 0);
        if (surface) {
            /* Write the pixels upside down into the bitmap buffer */
            int y = surface->h;
            while (y--) {
                Uint8 *src = (Uint8 *) surface->pixels + y * surface->pitch;
                SDL_RWwrite(dst, src, surface->pitch, 1);
            }
            SDL_FreeSurface(surface);

/* TODO: create the icon in WinCE (CreateIconFromResource isn't available) */
#ifndef _WIN32_WCE
            hicon =
                CreateIconFromResource(icon_bmp, icon_len, TRUE, 0x00030000);
#endif
        }
        SDL_RWclose(dst);
        SDL_stack_free(icon_bmp);
    }

    /* Set the icon for the window */
    SendMessage(hwnd, WM_SETICON, ICON_SMALL, (LPARAM) hicon);

    /* Set the icon in the task manager (should we do this?) */
    SendMessage(hwnd, WM_SETICON, ICON_BIG, (LPARAM) hicon);
}

void
WIN_SetWindowPosition(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;
    RECT rect;
    DWORD style;
    HWND top;
    BOOL menu;
    int x, y;

    /* Figure out what the window area will be */
    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        top = HWND_TOPMOST;
    } else {
        top = HWND_NOTOPMOST;
    }
    style = GetWindowLong(hwnd, GWL_STYLE);
    rect.left = 0;
    rect.top = 0;
    rect.right = window->w;
    rect.bottom = window->h;
#ifdef _WIN32_WCE
    menu = FALSE;
#else
    menu = (style & WS_CHILDWINDOW) ? FALSE : (GetMenu(hwnd) != NULL);
#endif
    AdjustWindowRectEx(&rect, style, menu, 0);

    if ((window->flags & SDL_WINDOW_FULLSCREEN)
        || window->x == SDL_WINDOWPOS_CENTERED) {
        x = (GetSystemMetrics(SM_CXSCREEN) - window->w) / 2;
    } else {
        x = window->x + rect.left;
    }
    if ((window->flags & SDL_WINDOW_FULLSCREEN)
        || window->y == SDL_WINDOWPOS_CENTERED) {
        y = (GetSystemMetrics(SM_CYSCREEN) - window->h) / 2;
    } else {
        y = window->y + rect.top;
    }

    SetWindowPos(hwnd, top, x, y, 0, 0, (SWP_NOCOPYBITS | SWP_NOSIZE));
}

void
WIN_SetWindowSize(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;
    RECT rect;
    DWORD style;
    HWND top;
    BOOL menu;
    int w, h;

    /* Figure out what the window area will be */
    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        top = HWND_TOPMOST;
    } else {
        top = HWND_NOTOPMOST;
    }
    style = GetWindowLong(hwnd, GWL_STYLE);
    rect.left = 0;
    rect.top = 0;
    rect.right = window->w;
    rect.bottom = window->h;
#ifdef _WIN32_WCE
    menu = FALSE;
#else
    menu = (style & WS_CHILDWINDOW) ? FALSE : (GetMenu(hwnd) != NULL);
#endif
    AdjustWindowRectEx(&rect, style, menu, 0);
    w = (rect.right - rect.left);
    h = (rect.bottom - rect.top);

    SetWindowPos(hwnd, top, 0, 0, w, h, (SWP_NOCOPYBITS | SWP_NOMOVE));
}

void
WIN_ShowWindow(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;

    ShowWindow(hwnd, SW_SHOW);

#ifdef _WIN32_WCE
    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        CE_SHFullScreen(hwnd,
                        SHFS_HIDESTARTICON | SHFS_HIDETASKBAR |
                        SHFS_HIDESIPBUTTON);
    }
#endif
}

void
WIN_HideWindow(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;

    ShowWindow(hwnd, SW_HIDE);

#ifdef _WIN32_WCE
    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        CE_SHFullScreen(hwnd,
                        SHFS_SHOWSTARTICON | SHFS_SHOWTASKBAR |
                        SHFS_SHOWSIPBUTTON);
    }
#endif
}

void
WIN_RaiseWindow(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;
    HWND top;

    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        top = HWND_TOPMOST;
    } else {
        top = HWND_NOTOPMOST;
    }
    SetWindowPos(hwnd, top, 0, 0, 0, 0, (SWP_NOMOVE | SWP_NOSIZE));

#ifdef _WIN32_WCE
    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        CE_SHFullScreen(hwnd,
                        SHFS_HIDESTARTICON | SHFS_HIDETASKBAR |
                        SHFS_HIDESIPBUTTON);
    }
#endif
}

void
WIN_MaximizeWindow(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;

    ShowWindow(hwnd, SW_MAXIMIZE);

#ifdef _WIN32_WCE
    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        CE_SHFullScreen(hwnd,
                        SHFS_HIDESTARTICON | SHFS_HIDETASKBAR |
                        SHFS_HIDESIPBUTTON);
    }
#endif
}

void
WIN_MinimizeWindow(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;

    ShowWindow(hwnd, SW_MINIMIZE);

#ifdef _WIN32_WCE
    if (window->flags & SDL_WINDOW_FULLSCREEN) {
        CE_SHFullScreen(hwnd,
                        SHFS_SHOWSTARTICON | SHFS_SHOWTASKBAR |
                        SHFS_SHOWSIPBUTTON);
    }
#endif
}

void
WIN_RestoreWindow(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;

    ShowWindow(hwnd, SW_RESTORE);
}

void
WIN_SetWindowGrab(_THIS, SDL_Window * window)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;

    if ((window->flags & (SDL_WINDOW_INPUT_GRABBED | SDL_WINDOW_FULLSCREEN))
        && (window->flags & SDL_WINDOW_INPUT_FOCUS)) {
        RECT rect;
        GetClientRect(hwnd, &rect);
        ClientToScreen(hwnd, (LPPOINT) & rect);
        ClientToScreen(hwnd, (LPPOINT) & rect + 1);
        ClipCursor(&rect);
    } else {
        ClipCursor(NULL);
    }
}

void
WIN_DestroyWindow(_THIS, SDL_Window * window)
{
    SDL_VideoData *videodata = (SDL_VideoData *) _this->driverdata;
    SDL_WindowData *data = (SDL_WindowData *) window->driverdata;

    if (data) {
        ReleaseDC(data->hwnd, data->hdc);
        if (data->created) {
            if (videodata->wintabDLL) {
                videodata->WTClose(g_hCtx[window->id]);
            }
            DestroyWindow(data->hwnd);
        }
        SDL_free(data);
    }
}

SDL_bool
WIN_GetWindowWMInfo(_THIS, SDL_Window * window, SDL_SysWMinfo * info)
{
    HWND hwnd = ((SDL_WindowData *) window->driverdata)->hwnd;
    if (info->version.major <= SDL_MAJOR_VERSION) {
        info->window = hwnd;
        return SDL_TRUE;
    } else {
        SDL_SetError("Application not compiled with SDL %d.%d\n",
                     SDL_MAJOR_VERSION, SDL_MINOR_VERSION);
        return SDL_FALSE;
    }
}


/*
 * Creates a HelperWindow used for DirectInput events.
 */
int
SDL_HelperWindowCreate(void)
{
    HINSTANCE hInstance = GetModuleHandle(NULL);
    WNDCLASS wce;

    /* Make sure window isn't created twice. */
    if (SDL_HelperWindow != NULL) {
        return 0;
    }

    /* Create the class. */
    SDL_zero(wce);
    wce.lpfnWndProc = DefWindowProc;
    wce.lpszClassName = (LPCWSTR) SDL_HelperWindowClassName;
    wce.hInstance = hInstance;

    /* Register the class. */
    SDL_HelperWindowClass = RegisterClass(&wce);
    if (SDL_HelperWindowClass == 0) {
        SDL_SetError("Unable to create Helper Window Class: error %d.",
                     GetLastError());
        return -1;
    }

    HWND hWndParent = NULL;
#ifndef _WIN32_WCE
    /* WinCE doesn't have HWND_MESSAGE */
    hWndParent = HWND_MESSAGE;
#endif

    /* Create the window. */
    SDL_HelperWindow = CreateWindowEx(0, SDL_HelperWindowClassName,
                                      SDL_HelperWindowName,
                                      WS_OVERLAPPED, CW_USEDEFAULT,
                                      CW_USEDEFAULT, CW_USEDEFAULT,
                                      CW_USEDEFAULT, hWndParent, NULL,
                                      hInstance, NULL);
    if (SDL_HelperWindow == NULL) {
        UnregisterClass(SDL_HelperWindowClassName, hInstance);
        SDL_SetError("Unable to create Helper Window: error %d.",
                     GetLastError());
        return -1;
    }

    return 0;
}


/*
 * Destroys the HelperWindow previously created with SDL_HelperWindowCreate.
 */
void
SDL_HelperWindowDestroy(void)
{
    HINSTANCE hInstance = GetModuleHandle(NULL);

    /* Destroy the window. */
    if (SDL_HelperWindow != NULL) {
        if (DestroyWindow(SDL_HelperWindow) == 0) {
            SDL_SetError("Unable to destroy Helper Window: error %d.",
                         GetLastError());
            return;
        }
        SDL_HelperWindow = NULL;
    }

    /* Unregister the class. */
    if (SDL_HelperWindowClass != 0) {
        if ((UnregisterClass(SDL_HelperWindowClassName, hInstance)) == 0) {
            SDL_SetError("Unable to destroy Helper Window Class: error %d.",
                         GetLastError());
            return;
        }
        SDL_HelperWindowClass = 0;
    }
}


/* vi: set ts=4 sw=4 expandtab: */