in rtkCudaBackProjectionImageFilter.cu: -Changed to from 3D texture to 2D layered texture -renamed variables (dim -> size) -store volume size in constant memory -removed kernel_optim, as it conflicted with recent optimization
in rtkCudaBackProjectionImageFilter.cu:
-Changed to from 3D texture to 2D layered texture
-renamed variables (dim -> size)
-store volume size in constant memory
-removed kernel_optim, as it conflicted with recent optimization

fabienmomey/RTK,SimonRit/RTK,SimonRit/RTK,fabienmomey/RTK,fabienmomey/RTK,SimonRit/RTK,fabienmomey/RTK,fabienmomey/RTK,fabienmomey/RTK,SimonRit/RTK,fabienmomey/RTK