wined3d: Add a state table entry for WINED3DRS_TWEENFACTOR.

dlls/wined3d/state.c

@@ -5413,6 +5413,8 @@ const struct StateEntryTemplate ffp_vertexstate_template[] = {
     { STATE_RENDER(WINED3DRS_POINTSIZE_MAX),              { STATE_RENDER(WINED3DRS_POINTSIZE_MIN),              state_psizemin_arb  }, ARB_POINT_PARAMETERS            },
     { STATE_RENDER(WINED3DRS_POINTSIZE_MAX),              { STATE_RENDER(WINED3DRS_POINTSIZE_MIN),              state_psizemin_ext  }, EXT_POINT_PARAMETERS            },
     { STATE_RENDER(WINED3DRS_POINTSIZE_MAX),              { STATE_RENDER(WINED3DRS_POINTSIZE_MIN),              state_psizemin_w    }, WINED3D_GL_EXT_NONE             },
+    { STATE_RENDER(WINED3DRS_TWEENFACTOR),                { STATE_RENDER(WINED3DRS_VERTEXBLEND),                state_vertexblend   }, WINED3D_GL_EXT_NONE             },
+
     /* Samplers for NP2 texture matrix adjustions. They are not needed if GL_ARB_texture_non_power_of_two is supported,
      * so register a NULL state handler in that case to get the vertex part of sampler() skipped(VTF is handled in the misc states.
      * otherwise, register sampler_texmatrix, which takes care of updating the texture matrix