ddraw: COM cleanup for the IDirect3DVertexBuffer7 iface.

dlls/ddraw/ddraw.c

@@ -4956,7 +4956,7 @@ static HRESULT WINAPI d3d7_CreateVertexBuffer(IDirect3D7 *iface, D3DVERTEXBUFFER
     if (hr == D3D_OK)
     {
         TRACE("Created vertex buffer %p.\n", object);
-        *vertex_buffer = (IDirect3DVertexBuffer7 *)object;
+        *vertex_buffer = &object->IDirect3DVertexBuffer7_iface;
     }
     else
         WARN("Failed to create vertex buffer, hr %#x.\n", hr);

dlls/ddraw/ddraw_private.h

@@ -519,8 +519,7 @@ HRESULT d3d_execute_buffer_execute(IDirect3DExecuteBufferImpl *execute_buffer,
  *****************************************************************************/
 struct IDirect3DVertexBufferImpl
 {
-    /*** IUnknown Methods ***/
-    const IDirect3DVertexBuffer7Vtbl *lpVtbl;
+    IDirect3DVertexBuffer7 IDirect3DVertexBuffer7_iface;
     IDirect3DVertexBuffer IDirect3DVertexBuffer_iface;
     LONG ref;
 

dlls/ddraw/device.c

@@ -4132,7 +4132,7 @@ static HRESULT WINAPI IDirect3DDeviceImpl_3_DrawPrimitiveVB(IDirect3DDevice3 *if
             iface, PrimitiveType, D3DVertexBuf, StartVertex, NumVertices, Flags);
 
     return IDirect3DDevice7_DrawPrimitiveVB((IDirect3DDevice7 *)device_from_device3(iface),
-            PrimitiveType, (IDirect3DVertexBuffer7 *)vb, StartVertex, NumVertices, Flags);
+            PrimitiveType, &vb->IDirect3DVertexBuffer7_iface, StartVertex, NumVertices, Flags);
 }
 
 
@@ -4294,7 +4294,8 @@ static HRESULT WINAPI IDirect3DDeviceImpl_3_DrawIndexedPrimitiveVB(IDirect3DDevi
             iface, PrimitiveType, D3DVertexBuf, Indices, IndexCount, Flags);
 
     return IDirect3DDevice7_DrawIndexedPrimitiveVB((IDirect3DDevice7 *)device_from_device3(iface),
-            PrimitiveType, (IDirect3DVertexBuffer7 *)vb, 0, IndexCount, Indices, IndexCount, Flags);
+            PrimitiveType, &vb->IDirect3DVertexBuffer7_iface, 0, IndexCount, Indices, IndexCount,
+            Flags);
 }
 
 /*****************************************************************************