diff --git a/reactos/include/ddk/winddi.h b/reactos/include/ddk/winddi.h
new file mode 100644
index 00000000000..d8f1d006dca
--- /dev/null
+++ b/reactos/include/ddk/winddi.h
@@ -0,0 +1,166 @@
+/*
+ * WinDDI.h - definition of the GDI - DDI interface
+ */
+
+typedef HANDLE  HBITMAP;
+typedef HANDLE  HDEV;
+typedef HANDLE  HPALETTE;
+typedef HANDLE  HSURF;
+
+typedef HANDLE  DHPDEV;
+
+typedef ULONG  (*PFN)();
+
+typedef struct _DRVFN
+{
+  ULONG  iFunc;
+  PFN  pfn;
+} DRVFN, *PDRVFN;
+
+/*
+ * DRVENABLEDATA - this structure is passed to the DDI from the GDI
+ *   in the function DrvEnableDriver to determine driver parameters.
+ */
+
+typedef struct _DRVENABLEDATA
+{
+  ULONG  iDriverVersion;
+  ULONG  c;
+  DRVFN  *pdrvfn;
+} DRVENABLEDATA, *PDRVENABLEDATA;
+ 
+typedef struct _DEVINFO 
+{
+  ULONG  flGraphicsCaps;
+  LOGFONTW  lfDefaultFont;
+  LOGFONTW  lfAnsiVarFont;
+  LOGFONTW  lfAnsiFixFont;
+  ULONG  cFonts;
+  ULONG  iDitherFormat;
+  USHORT  cxDither;
+  USHORT  cyDither;
+  HPALETTE  hpalDefault;
+} DEVINFO, *PDEVINFO;
+
+#define  DMMAXDEVICENAME  32
+#define  DMMAXFORMNAME  32
+
+typedef struct _DEVMODEW 
+{
+  WCHAR  dmDeviceName[DMMAXDEVICENAME];
+  WORD  dmSpecVersion;
+  WORD  dmDriverVersion;
+  WORD  dmSize;
+  WORD  dmDriverExtra;
+  DWORD  dmFields;
+  short  dmOrientation;
+  short  dmPaperSize;
+  short  dmPaperLength;
+  short  dmPaperWidth;
+  short  dmScale;
+  short  dmCopies;
+  short  dmDefaultSource;
+  short  dmPrintQuality;
+  short  dmColor;
+  short  dmDuplex;
+  short  dmYResolution;
+  short  dmTTOption;
+  short  dmCollate;
+  WCHAR  dmFormName[DMMAXFORMNAME];
+  WORD  dmLogPixels;
+  DWORD  dmBitsPerPel;
+  DWORD  dmPelsWidth;
+  DWORD  dmPelsHeight;
+  DWORD  dmDisplayFlags;
+  DWORD  dmDisplayFrequency;
+} DEVMODEW;
+
+/*  EngAssocateSurface hook flags  */
+#define  HOOK_BITBLT             0x00000001
+#define  HOOK_STRETCHBLT         0x00000002
+#define  HOOK_TEXTOUT            0x00000004
+#define  HOOK_PAINT              0x00000008
+#define  HOOK_STROKEPATH         0x00000010
+#define  HOOK_FILLPATH           0x00000020
+#define  HOOK_STROKEANDFILLPATH  0x00000040
+#define  HOOK_LINETO             0x00000080
+#define  HOOK_COPYBITS           0x00000100
+#define  HOOK_SYNCHRONIZE        0x00000200
+#define  HOOK_SYNCHRONIZEACCESS  0x00000400
+
+/*  EngCreateBitmap format types  */
+enum _BMF_TYPES
+{
+  BMF_1BPP = 1,
+  BMF_4BPP,
+  BMF_8BPP,
+  BMF_16BPP, 
+  BMF_24BPP, 
+  BMF_32BPP, 
+  BMF_4RLE, 
+  BMF_8RLE
+};
+ 
+#define  BMF_TOPDOWN     0x00000001
+#define  BMF_NOZEROINIT  0x00000002
+#define  BMF_USERMEM     0x00000004
+
+/*  EngCreatePalette mode types  */
+enum _PAL_TYPES
+{
+  PAL_INDEXED = 1,
+  PAL_BITFIELDS,
+  PAL_RGB,
+  PAL_BGR
+};
+
+/*
+ * Functions Prefixed with Drv are calls made from GDI to DDI, and
+ * those prefixed with Eng are calls made from DDI to GDI.  DDI is
+ * not allowed to make calls to any other kernel or user modules.
+ */
+
+/*  GDI --> DDI calls  */
+VOID DrvCompletePDEV(IN DHPDEV PDev,
+                     IN HDEV Dev);
+VOID DrvDisablePDEV(IN DHPDEV PDev); 
+VOID DrvDisableSurface(IN DHPDEV PDev); 
+BOOL DrvEnableDriver(IN ULONG Version, 
+                     IN ULONG DEDSize, 
+                     OUT PDRVENABLEDATA DED);
+DHPDEV DrvEnablePDEV(IN DEVMODEW  *DM,
+                     IN LPWSTR  LogAddress,
+                     IN ULONG  PatternCount,
+                     OUT HSURF  *SurfPatterns,
+                     IN ULONG  CapsSize,
+                     OUT ULONG  *DevCaps,
+                     IN ULONG  DevInfoSize,
+                     OUT DEVINFO  *DI,
+                     IN LPWSTR  DevDataFile,
+                     IN LPWSTR  DeviceName,
+                     IN HANDLE  Driver);
+HSURF DrvEnableSurface(IN DHPDEV PDev);
+ULONG DrvGetModes(IN HANDLE Driver,
+                  IN ULONG DataSize,
+                  OUT PDEVMODEW DM);
+
+/*  DDI --> GDI calls  */
+BOOL EngAssociateSurface(IN HSURF  Surface,
+                         IN HDEV  Dev,
+                         IN ULONG  Hooks);
+HBITMAP EngCreateBitmap(IN SIZEL  Size,
+                        IN LONG  Width,
+                        IN ULONG  Format,
+                        IN ULONG  Flags,
+                        IN PVOID  Bits);
+HSURF EngCreateDeviceSurface(IN DHSURF  Surface,
+                             IN SIZEL  Size,
+                             IN ULONG  FormatVersion);
+HPALETTE EngCreatePalette(IN ULONG  Mode,
+                          IN ULONG  Colors, 
+                          IN PULONG  *Colors, 
+                          IN ULONG  Red, 
+                          IN ULONG  Green, 
+                          IN ULONG  Blue); 
+
+