Relative Positions

A ship is a big product and the co-ordinates may get such big numerical values (especially in the longitudinal direction of the ship) that it becomes impractical to use them directly. This problem could be solved by use of properly located local co-ordinate systems. However, there is a traditional way of specifying the longitudinal position in ship-building that eliminates this problem. Specified positions along the x-axis are assigned a frame number and the longitudinal position is most often specified as a distance for or aft of a specified frame position. In Hull it is possible to specify the longitudinal position accordingly and a similar facility has also been implemented for distances from the Center Line and above the Base Line.