In the same spirit that it has been done for points positioning preferring geometrical relation between symbols (referencing real graphical points) to XY coordinates, the page layout is as mush as possible human oriented. The system has the responsibility of the position of each diagram step according to the user specifications. Of course, Doodle follows the model order implicitly given by the user through the operator \step. It also respects all the configurable model parameters. These parameters allow users to control globally the page layout such as the bottom/top margin or the horizontal/vertical space between two steps. All those parameters have default value. Each of those parameters can be specified in the header block of the diagram. For instance we find an operator \bottom_margin which takes the length that Doodle has to left in the bottom of each page (expressed in millimeters).
Explain here in detail the concept of page automatic layout.