+bool wxBitmap::CreateFromImage( const wxImage& image, int depth )
+{
+    UnRef();
+
+    wxCHECK_MSG( image.Ok(), FALSE, wxT("invalid image") )
+    wxCHECK_MSG( depth == -1 || depth == 1, FALSE, wxT("invalid bitmap depth") )
+
+    int width = image.GetWidth();
+    int height = image.GetHeight();
+
+    if ( width <= 0 || height <= 0 )
+    {
+        return false;
+    }
+
+    m_refData = new wxBitmapRefData();
+
+    SetHeight( height );
+    SetWidth( width );
+
+    // ------
+    // conversion to mono bitmap:
+    // ------
+    if (depth == 1)
+    {
+        SetBitmap( gdk_pixmap_new( wxGetRootWindow()->window, width, height, 1 ) );
+
+        SetDepth( 1 );
+
+        GdkVisual *visual = wxTheApp->GetGdkVisual();
+
+        // Create picture image
+
+        unsigned char *data_data = (unsigned char*)malloc( ((width >> 3)+8) * height );
+
+        GdkImage *data_image =
+            gdk_image_new_bitmap( visual, data_data, width, height );
+
+        // Create mask image
+
+        GdkImage *mask_image = (GdkImage*) NULL;
+
+        if (image.HasMask())
+        {
+            unsigned char *mask_data = (unsigned char*)malloc( ((width >> 3)+8) * height );
+
+            mask_image =  gdk_image_new_bitmap( visual, mask_data, width, height );
+
+            wxMask *mask = new wxMask();
+            mask->m_bitmap = gdk_pixmap_new( wxGetRootWindow()->window, width, height, 1 );
+
+            SetMask( mask );
+        }
+
+        int r_mask = image.GetMaskRed();
+        int g_mask = image.GetMaskGreen();
+        int b_mask = image.GetMaskBlue();
+
+        unsigned char* data = image.GetData();
+
+        int index = 0;
+        for (int y = 0; y < height; y++)
+        {
+            for (int x = 0; x < width; x++)
+            {
+                int r = data[index];
+                index++;
+                int g = data[index];
+                index++;
+                int b = data[index];
+                index++;
+
+                if (image.HasMask())
+                {
+                    if ((r == r_mask) && (b == b_mask) && (g == g_mask))
+                        gdk_image_put_pixel( mask_image, x, y, 1 );
+                    else
+                        gdk_image_put_pixel( mask_image, x, y, 0 );
+                }
+
+                if ((r == 255) && (b == 255) && (g == 255))
+                    gdk_image_put_pixel( data_image, x, y, 1 );
+                else
+                    gdk_image_put_pixel( data_image, x, y, 0 );
+
+            } // for
+        }  // for
+
+        // Blit picture
+
+        GdkGC *data_gc = gdk_gc_new( GetBitmap() );
+
+        gdk_draw_image( GetBitmap(), data_gc, data_image, 0, 0, 0, 0, width, height );
+
+        gdk_image_destroy( data_image );
+        gdk_gc_unref( data_gc );
+
+        // Blit mask
+
+        if (image.HasMask())
+        {
+            GdkGC *mask_gc = gdk_gc_new( GetMask()->GetBitmap() );
+
+            gdk_draw_image( GetMask()->GetBitmap(), mask_gc, mask_image, 0, 0, 0, 0, width, height );
+
+            gdk_image_destroy( mask_image );
+            gdk_gc_unref( mask_gc );
+        }
+    }
+
+    // ------
+    // conversion to colour bitmap:
+    // ------
+    else
+    {
+        SetPixmap( gdk_pixmap_new( wxGetRootWindow()->window, width, height, -1 ) );
+
+        GdkVisual *visual = wxTheApp->GetGdkVisual();
+
+        int bpp = visual->depth;
+
+        SetDepth( bpp );
+
+        if ((bpp == 16) && (visual->red_mask != 0xf800))
+            bpp = 15;
+        else if (bpp < 8)
+            bpp = 8;
+
+        // We handle 8-bit bitmaps ourselves using the colour cube, 12-bit
+        // visuals are not supported by GDK so we do these ourselves, too.
+        // 15-bit and 16-bit should actually work and 24-bit certainly does.
+#ifdef __sgi
+        if (!image.HasMask() && (bpp > 16))
+#else
+        if (!image.HasMask() && (bpp > 12))
+#endif
+        {
+            static bool s_hasInitialized = FALSE;
+
+            if (!s_hasInitialized)
+            {
+                gdk_rgb_init();
+                s_hasInitialized = TRUE;
+            }
+
+            GdkGC *gc = gdk_gc_new( GetPixmap() );
+
+            gdk_draw_rgb_image( GetPixmap(),
+                                gc,
+                                0, 0,
+                                width, height,
+                                GDK_RGB_DITHER_NONE,
+                                image.GetData(),
+                                width*3 );
+
+            gdk_gc_unref( gc );
+            return TRUE;
+        }
+
+        // Create picture image
+
+        GdkImage *data_image =
+            gdk_image_new( GDK_IMAGE_FASTEST, visual, width, height );
+
+        // Create mask image
+
+        GdkImage *mask_image = (GdkImage*) NULL;
+
+        if (image.HasMask())
+        {
+            unsigned char *mask_data = (unsigned char*)malloc( ((width >> 3)+8) * height );
+
+            mask_image =  gdk_image_new_bitmap( visual, mask_data, width, height );
+
+            wxMask *mask = new wxMask();
+            mask->m_bitmap = gdk_pixmap_new( wxGetRootWindow()->window, width, height, 1 );
+
+            SetMask( mask );
+        }
+
+        // Render
+
+        enum byte_order { RGB, RBG, BRG, BGR, GRB, GBR };
+        byte_order b_o = RGB;
+
+        if (bpp > 8)
+        {
+            if ((visual->red_mask > visual->green_mask) && (visual->green_mask > visual->blue_mask))      b_o = RGB;
+            else if ((visual->red_mask > visual->blue_mask) && (visual->blue_mask > visual->green_mask))  b_o = RBG;
+            else if ((visual->blue_mask > visual->red_mask) && (visual->red_mask > visual->green_mask))   b_o = BRG;
+            else if ((visual->blue_mask > visual->green_mask) && (visual->green_mask > visual->red_mask)) b_o = BGR;
+            else if ((visual->green_mask > visual->red_mask) && (visual->red_mask > visual->blue_mask))   b_o = GRB;
+            else if ((visual->green_mask > visual->blue_mask) && (visual->blue_mask > visual->red_mask))  b_o = GBR;
+        }
+
+        int r_mask = image.GetMaskRed();
+        int g_mask = image.GetMaskGreen();
+        int b_mask = image.GetMaskBlue();
+
+        unsigned char* data = image.GetData();
+
+        int index = 0;
+        for (int y = 0; y < height; y++)
+        {
+            for (int x = 0; x < width; x++)
+            {
+                int r = data[index];
+                index++;
+                int g = data[index];
+                index++;
+                int b = data[index];
+                index++;
+
+                if (image.HasMask())
+                {
+                    if ((r == r_mask) && (b == b_mask) && (g == g_mask))
+                        gdk_image_put_pixel( mask_image, x, y, 1 );
+                    else
+                        gdk_image_put_pixel( mask_image, x, y, 0 );
+                }
+
+                switch (bpp)
+                {
+                    case 8:
+                    {
+                        int pixel = -1;
+                        if (wxTheApp->m_colorCube)
+                        {
+                            pixel = wxTheApp->m_colorCube[ ((r & 0xf8) << 7) + ((g & 0xf8) << 2) + ((b & 0xf8) >> 3) ];
+                        }
+                        else
+                        {
+                            GdkColormap *cmap = gtk_widget_get_default_colormap();
+                            GdkColor *colors = cmap->colors;
+                            int max = 3 * (65536);
+
+                            for (int i = 0; i < cmap->size; i++)
+                            {
+                                int rdiff = (r << 8) - colors[i].red;
+                                int gdiff = (g << 8) - colors[i].green;
+                                int bdiff = (b << 8) - colors[i].blue;
+                                int sum = ABS (rdiff) + ABS (gdiff) + ABS (bdiff);
+                                if (sum < max) { pixel = i; max = sum; }
+                            }
+                        }
+
+                        gdk_image_put_pixel( data_image, x, y, pixel );
+
+                        break;
+                    }
+                    case 12:  // SGI only
+                    {
+                        guint32 pixel = 0;
+                        switch (b_o)
+                        {
+                            case RGB: pixel = ((r & 0xf0) << 4) | (g & 0xf0) | ((b & 0xf0) >> 4); break;
+                            case RBG: pixel = ((r & 0xf0) << 4) | (b & 0xf0) | ((g & 0xf0) >> 4); break;
+                            case GRB: pixel = ((g & 0xf0) << 4) | (r & 0xf0) | ((b & 0xf0) >> 4); break;
+                            case GBR: pixel = ((g & 0xf0) << 4) | (b & 0xf0) | ((r & 0xf0) >> 4); break;
+                            case BRG: pixel = ((b & 0xf0) << 4) | (r & 0xf0) | ((g & 0xf0) >> 4); break;
+                            case BGR: pixel = ((b & 0xf0) << 4) | (g & 0xf0) | ((r & 0xf0) >> 4); break;
+                        }
+                        gdk_image_put_pixel( data_image, x, y, pixel );
+                        break;
+                    }
+                    case 15:
+                    {
+                        guint32 pixel = 0;
+                        switch (b_o)
+                        {
+                            case RGB: pixel = ((r & 0xf8) << 7) | ((g & 0xf8) << 2) | ((b & 0xf8) >> 3); break;
+                            case RBG: pixel = ((r & 0xf8) << 7) | ((b & 0xf8) << 2) | ((g & 0xf8) >> 3); break;
+                            case GRB: pixel = ((g & 0xf8) << 7) | ((r & 0xf8) << 2) | ((b & 0xf8) >> 3); break;
+                            case GBR: pixel = ((g & 0xf8) << 7) | ((b & 0xf8) << 2) | ((r & 0xf8) >> 3); break;
+                            case BRG: pixel = ((b & 0xf8) << 7) | ((r & 0xf8) << 2) | ((g & 0xf8) >> 3); break;
+                            case BGR: pixel = ((b & 0xf8) << 7) | ((g & 0xf8) << 2) | ((r & 0xf8) >> 3); break;
+                        }
+                        gdk_image_put_pixel( data_image, x, y, pixel );
+                        break;
+                    }
+                    case 16:
+                    {
+                        // I actually don't know if for 16-bit displays, it is alway the green
+                        // component or the second component which has 6 bits.
+                        guint32 pixel = 0;
+                        switch (b_o)
+                        {
+                            case RGB: pixel = ((r & 0xf8) << 8) | ((g & 0xfc) << 3) | ((b & 0xf8) >> 3); break;
+                            case RBG: pixel = ((r & 0xf8) << 8) | ((b & 0xfc) << 3) | ((g & 0xf8) >> 3); break;
+                            case GRB: pixel = ((g & 0xf8) << 8) | ((r & 0xfc) << 3) | ((b & 0xf8) >> 3); break;
+                            case GBR: pixel = ((g & 0xf8) << 8) | ((b & 0xfc) << 3) | ((r & 0xf8) >> 3); break;
+                            case BRG: pixel = ((b & 0xf8) << 8) | ((r & 0xfc) << 3) | ((g & 0xf8) >> 3); break;
+                            case BGR: pixel = ((b & 0xf8) << 8) | ((g & 0xfc) << 3) | ((r & 0xf8) >> 3); break;
+                        }
+                        gdk_image_put_pixel( data_image, x, y, pixel );
+                        break;
+                    }
+                    case 32:
+                    case 24:
+                    {
+                        guint32 pixel = 0;
+                        switch (b_o)
+                        {
+                            case RGB: pixel = (r << 16) | (g << 8) | b; break;
+                            case RBG: pixel = (r << 16) | (b << 8) | g; break;
+                            case BRG: pixel = (b << 16) | (r << 8) | g; break;
+                            case BGR: pixel = (b << 16) | (g << 8) | r; break;
+                            case GRB: pixel = (g << 16) | (r << 8) | b; break;
+                            case GBR: pixel = (g << 16) | (b << 8) | r; break;
+                        }
+                        gdk_image_put_pixel( data_image, x, y, pixel );
+                    }
+                    default: break;
+                }
+            } // for
+        }  // for
+
+        // Blit picture
+
+        GdkGC *data_gc = gdk_gc_new( GetPixmap() );
+
+        gdk_draw_image( GetPixmap(), data_gc, data_image, 0, 0, 0, 0, width, height );
+
+        gdk_image_destroy( data_image );
+        gdk_gc_unref( data_gc );
+
+        // Blit mask
+
+        if (image.HasMask())
+        {
+            GdkGC *mask_gc = gdk_gc_new( GetMask()->GetBitmap() );
+
+            gdk_draw_image( GetMask()->GetBitmap(), mask_gc, mask_image, 0, 0, 0, 0, width, height );
+
+            gdk_image_destroy( mask_image );
+            gdk_gc_unref( mask_gc );
+        }
+    }
+
+    return TRUE;
+}
+
+wxImage wxBitmap::ConvertToImage() const
+{
+    // the colour used as transparent one in wxImage and the one it is replaced
+    // with when it really occurs in the bitmap
+    static const int MASK_RED = 1;
+    static const int MASK_GREEN = 2;
+    static const int MASK_BLUE = 3;
+    static const int MASK_BLUE_REPLACEMENT = 2;
+
+    wxImage image;
+
+    wxCHECK_MSG( Ok(), wxNullImage, wxT("invalid bitmap") );
+
+    GdkImage *gdk_image = (GdkImage*) NULL;
+    if (GetPixmap())
+    {
+        gdk_image = gdk_image_get( GetPixmap(),
+                                   0, 0,
+                                   GetWidth(), GetHeight() );
+    }
+    else if (GetBitmap())
+    {
+        gdk_image = gdk_image_get( GetBitmap(),
+                                   0, 0,
+                                   GetWidth(), GetHeight() );
+    }
+    else
+    {
+        wxFAIL_MSG( wxT("Ill-formed bitmap") );
+    }
+
+    wxCHECK_MSG( gdk_image, wxNullImage, wxT("couldn't create image") );
+
+    image.Create( GetWidth(), GetHeight() );
+    char unsigned *data = image.GetData();
+
+    if (!data)
+    {
+        gdk_image_destroy( gdk_image );
+        wxFAIL_MSG( wxT("couldn't create image") );
+        return wxNullImage;
+    }
+
+    GdkImage *gdk_image_mask = (GdkImage*) NULL;
+    if (GetMask())
+    {
+        gdk_image_mask = gdk_image_get( GetMask()->GetBitmap(),
+                                        0, 0,
+                                        GetWidth(), GetHeight() );
+
+        image.SetMaskColour( MASK_RED, MASK_GREEN, MASK_BLUE );
+    }
+
+    int bpp = -1;
+    int red_shift_right = 0;
+    int green_shift_right = 0;
+    int blue_shift_right = 0;
+    int red_shift_left = 0;
+    int green_shift_left = 0;
+    int blue_shift_left = 0;
+    bool use_shift = FALSE;
+
+    if (GetPixmap())
+    {
+        GdkVisual *visual = gdk_window_get_visual( GetPixmap() );
+        if (visual == NULL)
+            visual = wxTheApp->GetGdkVisual();
+
+        bpp = visual->depth;
+        if (bpp == 16)
+            bpp = visual->red_prec + visual->green_prec + visual->blue_prec;
+        red_shift_right = visual->red_shift;
+        red_shift_left = 8-visual->red_prec;
+        green_shift_right = visual->green_shift;
+        green_shift_left = 8-visual->green_prec;
+        blue_shift_right = visual->blue_shift;
+        blue_shift_left = 8-visual->blue_prec;
+
+        use_shift = (visual->type == GDK_VISUAL_TRUE_COLOR) || (visual->type == GDK_VISUAL_DIRECT_COLOR);
+    }
+    if (GetBitmap())
+    {
+        bpp = 1;
+    }
+
+
+    GdkColormap *cmap = gtk_widget_get_default_colormap();
+
+    long pos = 0;
+    for (int j = 0; j < GetHeight(); j++)
+    {
+        for (int i = 0; i < GetWidth(); i++)
+        {
+            wxUint32 pixel = gdk_image_get_pixel( gdk_image, i, j );
+            if (bpp == 1)
+            {
+                if (pixel == 0)
+                {
+                    data[pos]   = 0;
+                    data[pos+1] = 0;
+                    data[pos+2] = 0;
+                }
+                else
+                {
+                    data[pos]   = 255;
+                    data[pos+1] = 255;
+                    data[pos+2] = 255;
+                }
+            }
+            else if (use_shift)
+            {
+                data[pos] =   (pixel >> red_shift_right)   << red_shift_left;
+                data[pos+1] = (pixel >> green_shift_right) << green_shift_left;
+                data[pos+2] = (pixel >> blue_shift_right)  << blue_shift_left;
+            }
+            else if (cmap->colors)
+            {
+                data[pos] =   cmap->colors[pixel].red   >> 8;
+                data[pos+1] = cmap->colors[pixel].green >> 8;
+                data[pos+2] = cmap->colors[pixel].blue  >> 8;
+            }
+            else
+            {
+                wxFAIL_MSG( wxT("Image conversion failed. Unknown visual type.") );
+            }
+
+            if (gdk_image_mask)
+            {
+                int mask_pixel = gdk_image_get_pixel( gdk_image_mask, i, j );
+                if (mask_pixel == 0)
+                {
+                    data[pos] = MASK_RED;
+                    data[pos+1] = MASK_GREEN;
+                    data[pos+2] = MASK_BLUE;
+                }
+                else if ( data[pos] == MASK_RED &&
+                            data[pos+1] == MASK_GREEN &&
+                                data[pos+2] == MASK_BLUE )
+                {
+                    data[pos+2] = MASK_BLUE_REPLACEMENT;
+                }
+            }
+
+            pos += 3;
+        }
+    }
+
+    gdk_image_destroy( gdk_image );
+    if (gdk_image_mask) gdk_image_destroy( gdk_image_mask );
+
+    return image;
+}
+