public void FinalizeGDI()
{
if (_hFirstMemDc != IntPtr.Zero)
{
Win32GDISupport.DeleteDC(_hFirstMemDc);
}
if (_hSecondMemDc != IntPtr.Zero)
{
Win32GDISupport.DeleteDC(_hSecondMemDc);
}
}
private void CreateOffScreenBitmap(ref IntPtr hMemDc)
{
int bitmapWidth = 0, bitmapHeight = 0;
//Caculate the cached bitmap size
LinkedListNode <Photo> node = _photos.First;
Photo photo;
do
{
photo = node.Value;
bitmapWidth = System.Math.Max(bitmapWidth, photo.Width);
bitmapHeight += photo.Height + PhotoInterval;
} while ((node = node.Next) != null);
if (hMemDc == _hFirstMemDc)
{
_firstBitmapSize.Width = bitmapWidth;
_firstBitmapSize.Height = bitmapHeight;
}
else
{
_secondBitmapSize.Width = bitmapWidth;
_secondBitmapSize.Height = bitmapHeight;
}
// Create bimap
Graphics g = this.CreateGraphics();
IntPtr hDc = g.GetHdc();
IntPtr hBitmap = Win32GDISupport.CreateCompatibleBitmap(hDc, bitmapWidth, bitmapHeight);
IntPtr hOldBimap = Win32GDISupport.SelectObject(hMemDc, hBitmap);
if (hOldBimap != IntPtr.Zero)
{
Win32GDISupport.DeleteObject(hOldBimap);
}
IntPtr hPhotoDc = Win32GDISupport.CreateCompatibleDC(hDc);
g.ReleaseHdc();
//g.FillRectangle(_bkgdBrush, 0, 0, bitmap.Width, bitmap.Height);
Graphics gMem = Graphics.FromHdc(hMemDc);
node = _photos.First;
Rectangle rectPhoto = Rectangle.Empty;
PointF textLocation = new PointF(100, 100);
do
{
photo = node.Value;
rectPhoto.Size = photo.Size;
IntPtr hPhoto;
if (photo is ManagedPhoto)
{
hPhoto = photo.GetBitmap().GetHbitmap();
}
else if (photo is NativePhoto)
{
hPhoto = photo.GetHBitmap();
}
else
{
throw new NotSupportedException("Native bitmap is not supported by the photo class");
}
Win32GDISupport.SelectObject(hPhotoDc, hPhoto);
Win32GDISupport.SetStretchBltMode(hMemDc, Win32GDISupport.StretchBltMode.HALFTONE);
Win32GDISupport.StretchBlt(hMemDc, rectPhoto.X, rectPhoto.Y, rectPhoto.Width, rectPhoto.Height,
hPhotoDc, 0, 0, photo.UnZoomWidth, photo.UnZoomHeight, Win32GDISupport.TernaryRasterOperations.SRCCOPY);
if (photo is ManagedPhoto)
{
Win32GDISupport.DeleteObject(hPhoto);
}
//gMem.DrawImage(photo.Bitmap, rectPhoto);
gMem.DrawString(photo.Number.ToString(), SystemFonts.DefaultFont, Brushes.White, textLocation);
textLocation.Y += rectPhoto.Height + PhotoInterval;
rectPhoto.Y += rectPhoto.Height + PhotoInterval;
} while ((node = node.Next) != null);
Win32GDISupport.DeleteDC(hPhotoDc);
gMem.Dispose();
Trace.WriteLine("++++++Bitmap created, photo number " + _photos.First().Number +
" to " + _photos.Last().Number);
GC.Collect();
}
