diff --git a/clipper.c b/clipper.c
index 949c607..7497ef4 100644
--- a/clipper.c
+++ b/clipper.c
@@ -70,10 +70,8 @@ fakeDirectDrawClipper ciface =
     null  // ddraw_clipper_SetHwnd
 };
 
-HRESULT ddraw_CreateClipper(void *_This, DWORD dwFlags, LPDIRECTDRAWCLIPPER FAR *lplpDDClipper, IUnknown FAR *pUnkOuter )
+HRESULT __stdcall ddraw_CreateClipper(IDirectDrawImpl *This, DWORD dwFlags, LPDIRECTDRAWCLIPPER FAR *lplpDDClipper, IUnknown FAR *pUnkOuter )
 {
-    fakeDirectDrawClipperObject *This = (fakeDirectDrawClipperObject *)_This;
-
     printf("DirectDraw::CreateClipper(This=%p, dwFlags=%d, DDClipper=%p, unkOuter=%p)\n", This, (int)dwFlags, lplpDDClipper, pUnkOuter);
 
     fakeDirectDrawClipperObject *Clipper = (fakeDirectDrawClipperObject *)malloc(sizeof(fakeDirectDrawClipperObject));
diff --git a/clipper.h b/clipper.h
index 72fbbe5..c5458c3 100644
--- a/clipper.h
+++ b/clipper.h
@@ -19,6 +19,7 @@
 
 #include <windows.h>
 #include "ddraw.h"
+#include "main.h"
 
 typedef struct
 {
@@ -46,6 +47,6 @@ typedef struct
 
 extern fakeDirectDrawClipper ciface;
 
-HRESULT ddraw_CreateClipper(void *_This, DWORD dwFlags, LPDIRECTDRAWCLIPPER FAR *lplpDDClipper, IUnknown FAR *pUnkOuter );
+HRESULT __stdcall ddraw_CreateClipper(IDirectDrawImpl *This, DWORD dwFlags, LPDIRECTDRAWCLIPPER FAR *lplpDDClipper, IUnknown FAR *pUnkOuter );
 
 #endif
diff --git a/main.c b/main.c
index dc0d3fb..2d0b6eb 100644
--- a/main.c
+++ b/main.c
@@ -23,6 +23,38 @@
 #include "surface.h"
 #include "clipper.h"
 
+HRESULT __stdcall ddraw_Compact(IDirectDrawImpl *This)
+{
+    printf("DirectDraw::Compact(This=%p)\n", This);
+
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_DuplicateSurface(IDirectDrawImpl *This, LPDIRECTDRAWSURFACE src, LPDIRECTDRAWSURFACE *dest)
+{
+    printf("DirectDraw::DuplicateSurface(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_EnumDisplayModes(IDirectDrawImpl *This, DWORD a, LPDDSURFACEDESC b, LPVOID c, LPDDENUMMODESCALLBACK d)
+{
+    printf("DirectDraw::EnumDisplayModes(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_EnumSurfaces(IDirectDrawImpl *This, DWORD a, LPDDSURFACEDESC b, LPVOID c, LPDDENUMSURFACESCALLBACK d)
+{
+    printf("DirectDraw::EnumSurfaces(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_FlipToGDISurface(IDirectDrawImpl *This)
+{
+    printf("DirectDraw::FlipToGDISurface(This=%p)\n", This);
+
+    return DD_OK;
+}
+
 HRESULT __stdcall ddraw_GetCaps(IDirectDrawImpl *This, LPDDCAPS lpDDDriverCaps, LPDDCAPS lpDDEmulCaps)
 {
     printf("DirectDraw::GetCaps(This=%p, lpDDDriverCaps=%p, lpDDEmulCaps=%p)\n", This, lpDDDriverCaps, lpDDEmulCaps);
@@ -52,10 +84,51 @@ HRESULT __stdcall ddraw_GetCaps(IDirectDrawImpl *This, LPDDCAPS lpDDDriverCaps,
     return DD_OK;
 }
 
+HRESULT __stdcall ddraw_GetDisplayMode(IDirectDrawImpl *This, LPDDSURFACEDESC a)
+{
+    printf("DirectDraw::GetDisplayMode(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_GetFourCCCodes(IDirectDrawImpl *This, LPDWORD a, LPDWORD b)
+{
+    printf("DirectDraw::GetFourCCCodes(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_GetGDISurface(IDirectDrawImpl *This, LPDIRECTDRAWSURFACE *a)
+{
+    printf("DirectDraw::GetGDISurface(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_GetMonitorFrequency(IDirectDrawImpl *This, LPDWORD a)
+{
+    printf("DirectDraw::GetMonitorFrequency(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_GetScanLine(IDirectDrawImpl *This, LPDWORD a)
+{
+    printf("DirectDraw::GetScanLine(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_GetVerticalBlankStatus(IDirectDrawImpl *This, LPBOOL a)
+{
+    printf("DirectDraw::GetVerticalBlankStatus(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
+HRESULT __stdcall ddraw_Initialize(IDirectDrawImpl *This, GUID *a)
+{
+    printf("DirectDraw::Initialize(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
 HRESULT __stdcall ddraw_RestoreDisplayMode(IDirectDrawImpl *This)
 {
     printf("DirectDraw::RestoreDisplayMode(This=%p)\n", This);
-
     return DD_OK;
 }
 
@@ -71,11 +144,13 @@ HRESULT __stdcall ddraw_SetCooperativeLevel(IDirectDrawImpl *This, HWND hWnd, DW
 
     This->hWnd = hWnd;
 
+#ifndef USE_OPENGL
     if(IDirectDraw_SetCooperativeLevel(This->real_ddraw, hWnd, DDSCL_NORMAL) != DD_OK)
     {
         printf(" internal SetCooperativeLevel failed\n");
         return DDERR_GENERIC;
     }
+#endif
 
     return DD_OK;
 }
@@ -93,6 +168,12 @@ HRESULT __stdcall ddraw_SetDisplayMode(IDirectDrawImpl *This, DWORD width, DWORD
     return DD_OK;
 }
 
+HRESULT __stdcall ddraw_WaitForVerticalBlank(IDirectDrawImpl *This, DWORD a, HANDLE b)
+{
+    printf("DirectDraw::WaitForVerticalBlank(This=%p, ...)\n", This);
+    return DD_OK;
+}
+
 HRESULT __stdcall ddraw_QueryInterface(IDirectDrawImpl *This, REFIID riid, void **obj)
 {
     printf("DirectDraw::QueryInterface(This=%p, riid=%08X, obj=%p)\n", This, (unsigned int)riid, obj);
@@ -116,7 +197,9 @@ ULONG __stdcall ddraw_Release(IDirectDrawImpl *This)
 
     if(This->Ref == 0)
     {
+#ifndef USE_OPENGL
         IDirectDraw_Release(This->real_ddraw);
+#endif
         free(This);
         return 0;
     }
@@ -138,26 +221,26 @@ struct IDirectDrawImplVtbl iface =
     ddraw_AddRef,
     ddraw_Release,
     /* IDirectDrawImpl */
-    null, //Compact,
+    ddraw_Compact,
     ddraw_CreateClipper,
     ddraw_CreatePalette,
     ddraw_CreateSurface,
-    null, //DuplicateSurface,
-    null, //EnumDisplayModes,
-    null, //EnumSurfaces,
-    null, //FlipToGDISurface,
+    ddraw_DuplicateSurface,
+    ddraw_EnumDisplayModes,
+    ddraw_EnumSurfaces,
+    ddraw_FlipToGDISurface,
     ddraw_GetCaps,
-    null, //GetDisplayMode,
-    null, //GetFourCCCodes,
-    null, //GetGDISurface,
-    null, //GetMonitorFrequency,
-    null, //GetScanLine,
-    null, //GetVerticalBlankStatus,
-    null, //Initialize,
+    ddraw_GetDisplayMode,
+    ddraw_GetFourCCCodes,
+    ddraw_GetGDISurface,
+    ddraw_GetMonitorFrequency,
+    ddraw_GetScanLine,
+    ddraw_GetVerticalBlankStatus,
+    ddraw_Initialize,
     ddraw_RestoreDisplayMode,
     ddraw_SetCooperativeLevel,
     ddraw_SetDisplayMode,
-    null  //WaitForVerticalBlank
+    ddraw_WaitForVerticalBlank
 };
 
 int stdout_open = 0;
@@ -180,6 +263,7 @@ HRESULT WINAPI DirectDrawCreate(GUID FAR* lpGUID, LPDIRECTDRAW FAR* lplpDD, IUnk
     printf(" This = %p\n", This);
     *lplpDD = (LPDIRECTDRAW)This;
 
+#ifndef USE_OPENGL
     This->real_dll = LoadLibrary("system32\\ddraw.dll");
     if(!This->real_dll)
     {
@@ -191,6 +275,7 @@ HRESULT WINAPI DirectDrawCreate(GUID FAR* lpGUID, LPDIRECTDRAW FAR* lplpDD, IUnk
     {
         return DDERR_UNSUPPORTED;
     }
+#endif
 
     This->Ref = 0;
     ddraw_AddRef(This);
diff --git a/surface.c b/surface.c
index 05db13d..70cc2aa 100644
--- a/surface.c
+++ b/surface.c
@@ -23,7 +23,7 @@
 /* from main */
 HRESULT null();
 
-DWORD WINAPI ogl_Thread(void *_This);
+DWORD WINAPI ogl_Thread(IDirectDrawSurfaceImpl *This);
 DWORD WINAPI dd_Thread(IDirectDrawSurfaceImpl *This);
 void dump_ddsd(DWORD);
 void dump_ddscaps(DWORD);
@@ -246,7 +246,7 @@ struct IDirectDrawSurfaceImplVtbl siface =
     null  // ddraw_surface_UpdateOverlayZOrder
 };
 
-HRESULT ddraw_CreateSurface(IDirectDrawImpl *This, LPDDSURFACEDESC lpDDSurfaceDesc, LPDIRECTDRAWSURFACE FAR *lpDDSurface, IUnknown FAR * unkOuter)
+HRESULT __stdcall ddraw_CreateSurface(IDirectDrawImpl *This, LPDDSURFACEDESC lpDDSurfaceDesc, LPDIRECTDRAWSURFACE FAR *lpDDSurface, IUnknown FAR * unkOuter)
 {
     printf("DirectDraw::CreateSurface(This=%p, lpDDSurfaceDesc=%p, lpDDSurface=%p, unkOuter=%p)\n", This, lpDDSurfaceDesc, lpDDSurface, unkOuter);
 
@@ -277,7 +277,7 @@ HRESULT ddraw_CreateSurface(IDirectDrawImpl *This, LPDDSURFACEDESC lpDDSurfaceDe
             Surface->height = This->height;
             Surface->hWnd = This->hWnd;
 #if USE_OPENGL
-            Surface->dThread = CreateThread(NULL, 0, ogl_Thread, (void *)Surface, 0, NULL);
+            Surface->dThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)ogl_Thread, (void *)Surface, 0, NULL);
 #else
             Surface->dThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)dd_Thread, (void *)Surface, 0, NULL);
 #endif
diff --git a/surface.h b/surface.h
index c509118..dc1c6be 100644
--- a/surface.h
+++ b/surface.h
@@ -21,7 +21,7 @@
 #include "ddraw.h"
 #include "palette.h"
 
-HRESULT ddraw_CreateSurface(IDirectDrawImpl *This, LPDDSURFACEDESC DDSurfaceDesc, LPDIRECTDRAWSURFACE FAR *DDSurface, IUnknown FAR * unkOuter);
+HRESULT __stdcall ddraw_CreateSurface(IDirectDrawImpl *This, LPDDSURFACEDESC DDSurfaceDesc, LPDIRECTDRAWSURFACE FAR *DDSurface, IUnknown FAR * unkOuter);
 
 struct IDirectDrawSurfaceImpl;
 struct IDirectDrawSurfaceImplVtbl;