ddraw: Use unsafe_impl_from_IDirect3DDevice for application provided interfaces.

dlls/ddraw/ddraw_private.h

@@ -340,6 +340,8 @@ static inline IDirect3DDeviceImpl *device_from_device3(IDirect3DDevice3 *iface)
     return (IDirect3DDeviceImpl *)((char*)iface - FIELD_OFFSET(IDirect3DDeviceImpl, IDirect3DDevice3_vtbl));
 }
 
+IDirect3DDeviceImpl *unsafe_impl_from_IDirect3DDevice(IDirect3DDevice *iface) DECLSPEC_HIDDEN;
+
 /*****************************************************************************
  * IDirectDrawClipper implementation structure
  *****************************************************************************/

dlls/ddraw/device.c

@@ -6732,6 +6732,13 @@ static const struct IDirect3DDeviceVtbl d3d_device1_vtbl =
     IDirect3DDeviceImpl_1_GetDirect3D
 };
 
+IDirect3DDeviceImpl *unsafe_impl_from_IDirect3DDevice(IDirect3DDevice *iface)
+{
+    if (!iface) return NULL;
+    assert(iface->lpVtbl == &d3d_device1_vtbl);
+    return CONTAINING_RECORD(iface, IDirect3DDeviceImpl, IDirect3DDevice_vtbl);
+}
+
 /*****************************************************************************
  * IDirect3DDeviceImpl_UpdateDepthStencil
  *

dlls/ddraw/material.c

@@ -335,14 +335,15 @@ static HRESULT WINAPI IDirect3DMaterialImpl_2_GetHandle(IDirect3DMaterial2 *ifac
 }
 
 static HRESULT WINAPI IDirect3DMaterialImpl_1_GetHandle(IDirect3DMaterial *iface,
-        IDirect3DDevice *lpDirect3DDevice, D3DMATERIALHANDLE *lpHandle)
+        IDirect3DDevice *device, D3DMATERIALHANDLE *handle)
 {
     IDirect3DMaterialImpl *This = impl_from_IDirect3DMaterial(iface);
+    IDirect3DDeviceImpl *device_impl = unsafe_impl_from_IDirect3DDevice(device);
 
-    TRACE("iface %p, device %p, handle %p.\n", iface, lpDirect3DDevice, lpHandle);
+    TRACE("iface %p, device %p, handle %p.\n", iface, device, handle);
 
-    return IDirect3DMaterial3_GetHandle(&This->IDirect3DMaterial3_iface, lpDirect3DDevice ?
-            (IDirect3DDevice3 *)&device_from_device1(lpDirect3DDevice)->IDirect3DDevice3_vtbl : NULL, lpHandle);
+    return IDirect3DMaterial3_GetHandle(&This->IDirect3DMaterial3_iface, device_impl ?
+            (IDirect3DDevice3 *)&device_impl->IDirect3DDevice3_vtbl : NULL, handle);
 }
 
 static HRESULT WINAPI IDirect3DMaterialImpl_2_QueryInterface(IDirect3DMaterial2 *iface, REFIID riid,

dlls/ddraw/surface.c

@@ -4551,11 +4551,12 @@ static HRESULT WINAPI d3d_texture1_GetHandle(IDirect3DTexture *iface,
         IDirect3DDevice *device, D3DTEXTUREHANDLE *handle)
 {
     IDirectDrawSurfaceImpl *This = impl_from_IDirect3DTexture(iface);
-    IDirect3DDevice2 *device2 = (IDirect3DDevice2 *)&device_from_device1(device)->IDirect3DDevice2_vtbl;
+    IDirect3DDeviceImpl *device_impl = unsafe_impl_from_IDirect3DDevice(device);
 
     TRACE("iface %p, device %p, handle %p.\n", iface, device, handle);
 
-    return d3d_texture2_GetHandle(&This->IDirect3DTexture2_iface, device2, handle);
+    return d3d_texture2_GetHandle(&This->IDirect3DTexture2_iface,
+            device_impl ? (IDirect3DDevice2 *)&device_impl->IDirect3DDevice2_vtbl : NULL, handle);
 }
 
 /*****************************************************************************