A world file (.wld3) is a text file containing control points that describe a coordinate transformation. The control points reference coordinates in the CAD or BIM file and the corresponding points in a matching spatial reference. For the transformation information to be useful, it needs a matching spatial reference file (.prj).
The data comprises two sets of 3D points. Each row defines a displacement link using the following syntax: <From x,y,z> <space> <To x,y,z>. The first pair of coordinates in each row corresponds to the source coordinates, also known as the from coordinates. These values represent the x,y location of any known control point in the CAD drawing. The second pair of coordinates in each row corresponds to the destination coordinates, also known as the to coordinates. These values represent a new location in geographic space defined by the spatial reference of the CAD or BIM files.
The data looks similar to the following:
25933.063000,9032.704720,1702332.110159, 309622.102491,-8987.532001,1300.050854
32047.556994,13057.483520,1706354.400361 303697.073028,-9091.566340,1337.519601