sentences:  No 3D was available in RUCAPS though a totally separate 3D modelling and perspective hidden-line program called AUTOPROD written by Col. Nigel Hitch was sold alongside RUCAP.There was no database or modelling connection of any sort between RUCAPS and AUTOPROD.No clash-detection or calculations were undertaken on the model, but some hiding of one component by another was possible so that external walls showed on elevations while the internal elements were concealed in a 2½D fashion.