       const Scalar * __restrict__ voxels,
 #endif
       int firstSlice, int lastSlice,
-      int from, int to)
+      int2 from, int2 to)
 {
 #ifndef VOLTEX3D
 #ifdef PITCHED

    }

    // copy line to intermediate image
    for (int ix=threadIdx.x; ix<width; ix+=blockDim.x)
    {
        uchar4 *dest = img + line*width+ix;
        blend(dest, imgLine[ix]);

                 if not passed, the entire intermediate image will be rendered
*/
template<class Base>
void vvCudaSW<Base>::compositeVolume(int fromY, int toY)
{
   vvDebugMsg::msg(3, "vvCudaSW::compositeVolume(): ", fromY, toY);

   // If stacking==true then draw front to back, else draw back to front:
   int firstSlice = (Base::stacking) ? 0 : (Base::len[2]-1);  // first slice to process
