procedure TSkinEngine.DrawAlphaBlend(DC: HDC; X, Y, ClientWidth, ClientHeight: Integer;
  fBlend: Byte);
var
  hTempDC: HDC;
  bf: BLENDFUNCTION;
  hBmp: HBITMAP;
  bmi: BITMAPINFO;
  pvBits: Pointer;
begin
  hTempDC := CreateCompatibleDC(DC);

  ZeroMemory(@bmi, sizeof(BITMAPINFO));
  bmi.bmiHeader.biSize := sizeof(BITMAPINFOHEADER);
  bmi.bmiHeader.biWidth := ClientWidth;
  bmi.bmiHeader.biHeight := ClientHeight;
  bmi.bmiHeader.biPlanes := 1;
  bmi.bmiHeader.biBitCount := 32;
  bmi.bmiHeader.biCompression := BI_RGB;
  bmi.bmiHeader.biSizeImage := ClientWidth * ClientHeight * 4;

  hBmp := CreateDIBSection(hTempDC, bmi, DIB_RGB_COLORS, pvBits, 0, 0);
  SelectObject(hTempDC, hBmp);

  bf.BlendOp := AC_SRC_OVER;
  bf.BlendFlags := 0;
  bf.SourceConstantAlpha := fBlend;
  bf.AlphaFormat := 0;

  AlphaBlend(DC, X, Y, ClientWidth, ClientHeight, hTempDC, 0, 0, ClientWidth, ClientHeight, bf);

  DeleteObject(hBmp);
  DeleteDC(hTempDC);
end;