gimp/plug-ins/screenshot/screenshot-win32.c

/* GIMP - The GNU Image Manipulation Program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * Screenshot plug-in
 * Copyright 1998-2007 Sven Neumann <sven@gimp.org>
 * Copyright 2003      Henrik Brix Andersen <brix@gimp.org>
 * Copyright 2012      Simone Karin Lehmann - OS X patches
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "config.h"

#include <glib.h>

#ifdef G_OS_WIN32

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <windows.h>

#include <libgimp/gimp.h>
#include <libgimp/gimpui.h>

#include "screenshot.h"
#include "screenshot-win32.h"
#include "screenshot-win32-resource.h"

#include "libgimp/stdplugins-intl.h"

/*
 * Application definitions
 */
#define SELECT_FRAME    0
#define SELECT_CLIENT   1
#define SELECT_WINDOW   2

#define SHOW_WINDOW     FALSE
#define APP_NAME        "plug_in_screenshot_win"
#define WM_DOCAPTURE    (WM_USER + 100)

/* Prototypes */
void setCaptureType(int capType);
BOOL InitApplication(HINSTANCE hInstance);
BOOL InitInstance(HINSTANCE hInstance, int nCmdShow);
int winsnapWinMain(void);

/* File variables */
static int        captureType;
static char       buffer[512];
static guchar    *capBytes = NULL;
static HWND       mainHwnd = NULL;
static HINSTANCE  hInst = NULL;
static HCURSOR    selectCursor = 0;
static ICONINFO   iconInfo;

static gint32    *image_id;

static void sendBMPToGimp(HBITMAP hBMP, HDC hDC, RECT rect);
static void doWindowCapture(void);
static int  doCapture(HWND selectedHwnd);

BOOL CALLBACK dialogProc(HWND, UINT, WPARAM, LPARAM);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

/* Data structure holding data between runs */
typedef struct {
  gint root;
  guint delay;
  gint decor;
} WinSnapValues;

/* Default WinSnap values */
static WinSnapValues winsnapvals =
{
  FALSE,
  0,
  TRUE,
};

/* The dialog information */
typedef struct {
#ifdef CAN_SET_DECOR
  GtkWidget *decor_button;
#endif
  GtkWidget *single_button;
  GtkWidget *root_button;
  GtkWidget *delay_spinner;
} WinSnapInterface;

/* We create a DIB section to hold the grabbed area. The scanlines in
 * DIB sections are aligned on a LONG (four byte) boundary. Its pixel
 * data is in RGB (BGR actually) format, three bytes per pixel.
 *
 * GIMP uses no alignment for its pixel regions. The GIMP image we
 * create is of type RGB, i.e. three bytes per pixel, too. Thus in
 * order to be able to quickly transfer all of the image at a time, we
 * must use a DIB section and pixel region the scanline width in
 * bytes of which is evenly divisible with both 3 and 4. I.e. it must
 * be a multiple of 12 bytes, or in pixels, a multiple of four pixels.
 */

#define ROUND4(width) (((width-1)/4+1)*4)


gboolean
screenshot_win32_available (void)
{
  return TRUE;
}

ScreenshotCapabilities
screenshot_win32_get_capabilities (void)
{
  return (SCREENSHOT_CAN_SHOOT_DECORATIONS);
}

GimpPDBStatusType
screenshot_win32_shoot (ScreenshotValues  *shootvals,
                        GdkScreen         *screen,
                        gint32            *image_ID,
                        GError           **error)
{
  image_id = image_ID;

  winsnapvals.delay = shootvals->select_delay;

  if (shootvals->shoot_type == SHOOT_ROOT)
    {
        doCapture(0);
        return GIMP_PDB_SUCCESS;
    }
  else if (shootvals->shoot_type == SHOOT_WINDOW)
    {
       doWindowCapture();
       return GIMP_PDB_SUCCESS;
    }
  else if (shootvals->shoot_type == SHOOT_REGION)
    return GIMP_PDB_EXECUTION_ERROR;

  return GIMP_PDB_EXECUTION_ERROR;
}





/******************************************************************
 * GIMP format and transfer functions
 ******************************************************************/

/*
 * flipRedAndBlueBytes
 *
 * Microsoft has chosen to provide us a very nice (not!)
 * interface for retrieving bitmap bits.  DIBSections have
 * RGB information as BGR instead.  So, we have to swap
 * the silly red and blue bytes before sending to the
 * GIMP.
 */
static void
flipRedAndBlueBytes(int width, int height)
{
  int      i, j;
  guchar  *bufp;
  guchar   temp;

  j = 0;
  while (j < height) {
    i = width;
    bufp = capBytes + j*ROUND4(width)*3;
    while (i--) {
      temp = bufp[2];
      bufp[2] = bufp[0];
      bufp[0] = temp;
      bufp += 3;
    }
    j++;
  }
}

/*
 * sendBMPToGIMP
 *
 * Take the captured data and send it across
 * to GIMP.
 */
static void
sendBMPToGimp(HBITMAP hBMP, HDC hDC, RECT rect)
{
  int            width, height;
  int            imageType, layerType;
  gint32         new_image_id;
  gint32         layer_id;
  GeglBuffer    *buffer;
  GeglRectangle *rectangle;

  /* Our width and height */
  width = (rect.right - rect.left);
  height = (rect.bottom - rect.top);

  /* Check that we got the memory */
  if (!capBytes)
  {
    g_message (_("No data captured"));
    return;
  }

  /* Flip the red and blue bytes */
  flipRedAndBlueBytes(width, height);

  /* Set up the image and layer types */
  imageType = GIMP_RGB;
  layerType = GIMP_RGB_IMAGE;

  /* Create the GIMP image and layers */
  new_image_id = gimp_image_new(width, height, imageType);
  layer_id = gimp_layer_new(new_image_id, _("Background"),
                            ROUND4(width), height,
                            layerType, 100, GIMP_NORMAL_MODE);
  gimp_image_insert_layer(new_image_id, layer_id, -1, 0);

  /* make rectangle */
  rectangle = g_new (GeglRectangle, 1);
  rectangle->x = 0;
  rectangle->y = 0;
  rectangle->width = ROUND4(width);
  rectangle->height = height;

  /* get the buffer */
  buffer = gimp_drawable_get_buffer (layer_id);

  /* fill the buffer */
  gegl_buffer_set (buffer, rectangle, 0, NULL, (guchar *) capBytes, GEGL_AUTO_ROWSTRIDE);

  /* flushing data */
  gegl_buffer_flush (buffer);

  /* Now resize the layer down to the correct size if necessary. */
  if (width != ROUND4(width)) {
    gimp_layer_resize (layer_id, width, height, 0, 0);
    gimp_image_resize (new_image_id, width, height, 0, 0);
  }
  /* Finish up */

  *image_id = new_image_id;

  return;
}

/*
 * doNonRootWindowCapture
 *
 * Capture a selected window.
 * ENTRY POINT FOR WINSNAP NONROOT
 *
 */
static void
doWindowCapture(void)
{
  /* Start up a standard Win32
   * message handling loop for
   * selection of the window
   * to be captured
   */
  winsnapWinMain();
}

/******************************************************************
 * Debug stuff
 ******************************************************************/

/*
 * formatWindowsError
 *
 * Format the latest Windows error message into
 * a readable string.  Store in the provided
 * buffer.
 */
static void
formatWindowsError(char *buffer, int buf_size)
{
  LPVOID lpMsgBuf;

  /* Format the message */
  FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
    FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
    NULL, GetLastError(),
    MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
    (LPTSTR) &lpMsgBuf, 0, NULL );

  /* Copy to the buffer */
  strncpy(buffer, lpMsgBuf, buf_size - 1);

  LocalFree(lpMsgBuf);
}

/******************************************************************
 * Bitmap capture and handling
 ******************************************************************/

/*
 * primDoWindowCapture
 *
 * The primitive window capture functionality.  Accepts
 * the two device contexts and the rectangle to be
 * captured.
 */
static HBITMAP
primDoWindowCapture(HDC hdcWindow, HDC hdcCompat, RECT rect)
{
  HBITMAP hbmCopy;
  HGDIOBJ oldObject;
  BITMAPINFO  bmi;

  int width = (rect.right - rect.left);
  int height = (rect.bottom - rect.top);

  /* Create the bitmap info header */
  bmi.bmiHeader.biSize = sizeof(BITMAPINFOHEADER);
  bmi.bmiHeader.biWidth = ROUND4(width);
  bmi.bmiHeader.biHeight = -height;
  bmi.bmiHeader.biPlanes = 1;
  bmi.bmiHeader.biBitCount = 24;
  bmi.bmiHeader.biCompression = BI_RGB;
  bmi.bmiHeader.biSizeImage = 0;
  bmi.bmiHeader.biXPelsPerMeter =
  bmi.bmiHeader.biYPelsPerMeter = 0;
  bmi.bmiHeader.biClrUsed = 0;
  bmi.bmiHeader.biClrImportant = 0;

  /* Create the bitmap storage space */
  hbmCopy = CreateDIBSection(hdcCompat,
           (BITMAPINFO *) &bmi,
           DIB_RGB_COLORS,
           (void **)&capBytes, NULL, 0);
  if (!hbmCopy) {
    formatWindowsError(buffer, sizeof buffer);
    g_error("Error creating DIB section: %s", buffer);
  return NULL;
  }

  /* Select the bitmap into the compatible DC. */
  oldObject = SelectObject(hdcCompat, hbmCopy);
  if (!oldObject) {
    formatWindowsError(buffer, sizeof buffer);
    g_error("Error selecting object: %s", buffer);
    return NULL;
  }

  /* Copy the data from the application to the bitmap.  Even if we did
   * round up the width, BitBlt only the actual data.
   */
  if (!BitBlt(hdcCompat, 0,0,
        width, height,
        hdcWindow, 0,0,
        SRCCOPY)) {
    formatWindowsError(buffer, sizeof buffer);
    g_error("Error copying bitmap: %s", buffer);
    return NULL;
  }

  /* Restore the original object */
  SelectObject(hdcCompat, oldObject);

  return hbmCopy;
}

/*
 * doCapture
 *
 * Do the capture.  Accepts the window
 * handle to be captured or the NULL value
 * to specify the root window.
 */
static int
doCapture(HWND selectedHwnd)
{
  HDC   hdcSrc;
  HDC   hdcCompat;
  HRGN    capRegion;
  HWND    oldForeground;
  RECT    rect;
  HBITMAP hbm;

  /* Try and get everything out of the way before the
   * capture.
   */
  Sleep(500 + winsnapvals.delay * 1000);

  /* Are we capturing a window or the whole screen */
  if (selectedHwnd) {

    /* Set to foreground window */
    oldForeground = GetForegroundWindow();
    SetForegroundWindow(selectedHwnd);
    BringWindowToTop(selectedHwnd);

    Sleep(500);

    /* Build a region for the capture */
    GetWindowRect(selectedHwnd, &rect);
    capRegion = CreateRectRgn(rect.left, rect.top,
            rect.right, rect.bottom);
    if (!capRegion) {
      formatWindowsError(buffer, sizeof buffer);
      g_error("Error creating region: %s", buffer);
      return FALSE;
    }

    /* Get the device context for the selected
     * window.  Create a memory DC to use for the
     * Bit copy.
     */
    hdcSrc = GetDCEx(selectedHwnd, capRegion,
         DCX_WINDOW | DCX_PARENTCLIP | DCX_INTERSECTRGN);
  } else {
    /* Get the device context for the whole screen */
    hdcSrc = CreateDC("DISPLAY", NULL, NULL, NULL);

    /* Get the screen's rectangle */
    rect.top = 0;
    rect.bottom = GetDeviceCaps(hdcSrc, VERTRES);
    rect.left = 0;
    rect.right = GetDeviceCaps(hdcSrc, HORZRES);
  }

  if (!hdcSrc) {
    formatWindowsError(buffer, sizeof buffer);
    g_error("Error getting device context: %s", buffer);
    return FALSE;
  }
  hdcCompat = CreateCompatibleDC(hdcSrc);
  if (!hdcCompat) {
    formatWindowsError(buffer, sizeof buffer);
    g_error("Error getting compat device context: %s", buffer);
    return FALSE;
  }

  /* Do the window capture */
  hbm = primDoWindowCapture(hdcSrc, hdcCompat, rect);
  if (!hbm)
    return FALSE;

  /* Release the device context */
  ReleaseDC(selectedHwnd, hdcSrc);

  /* Replace the previous foreground window */
  if (selectedHwnd && oldForeground)
    SetForegroundWindow(oldForeground);

  /* Send the bitmap
   * TODO: Change this
   */
  if (hbm != NULL) {
    sendBMPToGimp(hbm, hdcCompat, rect);
  }

  return TRUE;
}

/******************************************************************
 * Win32 entry point and setup...
 ******************************************************************/

#define DINV 3

/*
 * highlightWindowFrame
 *
 * Highlight (or unhighlight) the specified
 * window handle's frame.
 */
static void
highlightWindowFrame(HWND hWnd)
{
  HDC     hdc;
  RECT    rc;

  if (!IsWindow(hWnd))
    return;

  hdc = GetWindowDC(hWnd);
  GetWindowRect(hWnd, &rc);
  OffsetRect(&rc, -rc.left, -rc.top);

  if (!IsRectEmpty(&rc)) {
    PatBlt(hdc, rc.left, rc.top, rc.right-rc.left, DINV, DSTINVERT);
    PatBlt(hdc, rc.left, rc.bottom-DINV, DINV, -(rc.bottom-rc.top-2*DINV),
     DSTINVERT);
    PatBlt(hdc, rc.right-DINV, rc.top+DINV, DINV, rc.bottom-rc.top-2*DINV,
     DSTINVERT);
    PatBlt(hdc, rc.right, rc.bottom-DINV, -(rc.right-rc.left), DINV,
     DSTINVERT);
  }

  ReleaseDC(hWnd, hdc);
  UpdateWindow(hWnd);
}

/*
 * setCaptureType
 *
 * Set the capture type.  Should be one of:
 * SELECT_FRAME
 * SELECT_CLIENT
 * SELECT_WINDOW
 */
void
setCaptureType(int capType)
{
  captureType = capType;
}

/*
 * myWindowFromPoint
 *
 * Map to the appropriate window from the
 * specified point.  The chosen window is
 * based on the current capture type.
 */
static HWND
myWindowFromPoint(POINT pt)
{
  HWND myHwnd;
  HWND nextHwnd;

  switch (captureType) {
  case SELECT_FRAME:
  case SELECT_CLIENT:
    nextHwnd = WindowFromPoint(pt);

    do {
      myHwnd = nextHwnd;
      nextHwnd = GetParent(myHwnd);
    } while (nextHwnd);

    return myHwnd;
    break;

  case SELECT_WINDOW:
    return WindowFromPoint(pt);
    break;
  }

  return WindowFromPoint(pt);
}

/*
 * dialogProc
 *
 * The window procedure for the window
 * selection dialog box.
 */
BOOL CALLBACK
dialogProc(HWND hwndDlg, UINT msg, WPARAM wParam, LPARAM lParam)
{
  static int   mouseCaptured;
  static int   buttonDown;
  static HCURSOR oldCursor;
  static RECT  bitmapRect;
  static HWND  highlightedHwnd = NULL;

  switch (msg) {
  case WM_INITDIALOG:
    {
      int nonclientHeight;
      HWND hwndGroup;
      RECT dlgRect;
      RECT clientRect;
      RECT groupRect;
      BITMAP bm;

      /* Set the mouse capture flag */
      buttonDown = 0;
      mouseCaptured = 0;

      /* Calculate the bitmap dimensions */
      GetObject(iconInfo.hbmMask, sizeof(BITMAP), (VOID *)&bm);

      /* Calculate the dialog window dimensions */
      GetWindowRect(hwndDlg, &dlgRect);

      /* Calculate the group box dimensions */
      hwndGroup = GetDlgItem(hwndDlg, IDC_GROUP);
      GetWindowRect(hwndGroup, &groupRect);
      OffsetRect(&groupRect, -dlgRect.left, -dlgRect.top);

      /* The client's rectangle */
      GetClientRect(hwndDlg, &clientRect);

      /* The non-client height */
      nonclientHeight = (dlgRect.bottom - dlgRect.top) -
          (clientRect.bottom - clientRect.top);

      /* Calculate the bitmap rectangle */
      bitmapRect.top = ((groupRect.top + groupRect.bottom) / 2) -
          (bm.bmHeight / 2);
      bitmapRect.top -= nonclientHeight;
      bitmapRect.bottom = bitmapRect.top + bm.bmHeight;
      bitmapRect.left = ((groupRect.left + groupRect.right) / 2) - (bm.bmWidth / 2);
      bitmapRect.right = bitmapRect.left + bm.bmWidth;
    }
    break;

  case WM_LBUTTONDOWN:
    /* Track the button down state */
    buttonDown = 1;
    break;

  case WM_LBUTTONUP:
    buttonDown = 0;

    /* If we have mouse captured
     * we do this stuff.
     */
    if (mouseCaptured) {
      HWND  selectedHwnd;
      POINT cursorPos;

      /* Release the capture */
      mouseCaptured = 0;
      SetCursor(oldCursor);
      ReleaseCapture();

      /* Remove the highlight */
      if (highlightedHwnd)
        highlightWindowFrame(highlightedHwnd);
      RedrawWindow(hwndDlg, NULL, NULL, RDW_INVALIDATE);

      /* Return the selected window */
      GetCursorPos(&cursorPos);
      selectedHwnd = myWindowFromPoint(cursorPos);
      EndDialog(hwndDlg, (INT_PTR) selectedHwnd);
    }
    break;

  case WM_MOUSEMOVE:
    /* If the mouse is captured, show
     * the window which is tracking
     * under the mouse position.
     */
    if (mouseCaptured) {
      HWND  currentHwnd;
      POINT cursorPos;

      /* Get the window */
      GetCursorPos(&cursorPos);
      currentHwnd = myWindowFromPoint(cursorPos);

      /* Do the highlighting */
      if (highlightedHwnd != currentHwnd) {
          if (highlightedHwnd)
            highlightWindowFrame(highlightedHwnd);
          if (currentHwnd)
            highlightWindowFrame(currentHwnd);
          highlightedHwnd = currentHwnd;
      }
      /* If the mouse has not been captured,
       * try to figure out if we should capture
       * the mouse.
       */
    } else if (buttonDown) {
      POINT cursorPos;

      /* Get the current client position */
      GetCursorPos(&cursorPos);
      ScreenToClient(hwndDlg, &cursorPos);

      /* Check if within the rectangle formed
       * by the bitmap
       */
      if (PtInRect(&bitmapRect, cursorPos)) {
          mouseCaptured = 1;
          oldCursor = SetCursor(selectCursor);
          SetCapture(hwndDlg);
          RedrawWindow(hwndDlg, NULL, NULL, RDW_INVALIDATE | RDW_ERASE);
      }
    }

    break;

  case WM_PAINT:
    {
      HDC          hDC;
      PAINTSTRUCT  ps;

      /* If the mouse is not captured draw
       * the cursor image
       */
      if (!mouseCaptured) {
          hDC = BeginPaint(hwndDlg, &ps);
          DrawIconEx(hDC, bitmapRect.left, bitmapRect.top, selectCursor,
                     0, 0, 0, NULL, DI_NORMAL);
          EndPaint(hwndDlg, &ps);
      }
    }
    break;

  case WM_COMMAND:
    /* Handle the cancel button */
    switch (LOWORD(wParam)) {
      case IDCANCEL:
        EndDialog(hwndDlg, 0);
        return TRUE;
        break;
    }

  }

  return FALSE;
}

///* Don't use the normal WinMain from gimp.h */
//#define WinMain WinMain_no_thanks
//MAIN()
//#undef WinMain

/*
 * WinMain
 *
 * The standard gimp plug-in WinMain won't quite cut it for
 * this plug-in.
 */
//int APIENTRY
//WinMain(HINSTANCE hInstance,
//  HINSTANCE hPrevInstance,
//  LPSTR     lpCmdLine,
//  int       nCmdShow)
//{
//  /*
//   * Normally, we would do all of the Windows-ish set up of
//   * the window classes and stuff here in WinMain.  But,
//   * the only time we really need the window and message
//   * queues is during the plug-in run.  So, all of that will
//   * be done during run().  This avoids all of the Windows
//   * setup stuff for the query().  Stash the instance handle now
//   * so it is available from the run() procedure.
//   */
//  hInst = hInstance;
//
//  /*
//   * Now, call gimp_main... This is what the normal WinMain()
//   * would do.
//   */
////  return gimp_main(&PLUG_IN_INFO, __argc, __argv);
//}

/*
 * InitApplication
 *
 * Initialize window data and register the window class
 */
BOOL
InitApplication(HINSTANCE hInstance)
{
  WNDCLASS wc;
  BOOL retValue;

  /* Get some resources */
#ifdef _MSC_VER
  /* For some reason this works only with MSVC */
  selectCursor = LoadCursor(hInstance, MAKEINTRESOURCE(IDC_SELECT));
#else
  selectCursor = LoadCursor(NULL, IDC_CROSS);
#endif
  GetIconInfo(selectCursor, &iconInfo);

  /*
   * Fill in window class structure with parameters to describe
   * the main window.
   */
  wc.style = CS_HREDRAW | CS_VREDRAW;
  wc.lpfnWndProc = (WNDPROC) WndProc;
  wc.cbClsExtra = 0;
  wc.cbWndExtra = 0;
  wc.hInstance = hInstance;
  wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
  wc.hCursor = LoadCursor(NULL, IDC_ARROW);
  wc.hbrBackground = (HBRUSH) (COLOR_WINDOW + 1);
  wc.lpszClassName = APP_NAME;
  wc.lpszMenuName = NULL;

  /* Register the window class and stash success/failure code. */
  retValue = RegisterClass(&wc);

  /* Log error */
  if (!retValue) {
    formatWindowsError(buffer, sizeof buffer);
    g_error("Error registering class: %s", buffer);
    return retValue;
  }

  return retValue;
}

/*
 * InitInstance
 *
 * Create the main window for the application.
 */
BOOL
InitInstance(HINSTANCE hInstance, int nCmdShow)
{
  /* Create our window */
  mainHwnd = CreateWindow(APP_NAME, APP_NAME, WS_OVERLAPPEDWINDOW,
        CW_USEDEFAULT, 0, CW_USEDEFAULT, 0,
        NULL, NULL, hInstance, NULL);

  if (!mainHwnd) {
    return (FALSE);
  }

  ShowWindow(mainHwnd, nCmdShow);
  UpdateWindow(mainHwnd);

  return TRUE;
}

/*
 * winsnapWinMain
 *
 * This is the function that represents the code that
 * would normally reside in WinMain (see above).  This
 * function will get called during run() in order to set
 * up the windowing environment necessary for WinSnap to
 * operate.
 */
int
winsnapWinMain(void)
{
  MSG msg;

  /* Perform instance initialization */
  if (!InitApplication(hInst))
    return (FALSE);

  /* Perform application initialization */
  if (!InitInstance(hInst, SHOW_WINDOW))
    return (FALSE);

  /* Main message loop */
  while (GetMessage(&msg, NULL, 0, 0)) {
    TranslateMessage(&msg);
    DispatchMessage(&msg);
  }

  return (msg.wParam);
}

/*
 * WndProc
 *
 * Process window message for the main window.
 */
LRESULT CALLBACK
WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
  HWND selectedHwnd;

  switch (message) {

  case WM_CREATE:
    /* The window is created... Send the capture message */
    PostMessage(hwnd, WM_DOCAPTURE, 0, 0);
    break;

  case WM_DOCAPTURE:
    /* Get the selected window handle */
    selectedHwnd = (HWND) DialogBox(hInst, MAKEINTRESOURCE(IDD_SELECT),
            hwnd, (DLGPROC) dialogProc);
    if (selectedHwnd)
      doCapture(selectedHwnd);

    PostQuitMessage(0);

    break;

  case WM_DESTROY:
    PostQuitMessage(0);
    break;

  default:
    return (DefWindowProc(hwnd, message, wParam, lParam));
  }

  return 0;
}

#endif /* G_OS_WIN32 */