Centering/Displacement
Previous  Top  Next

Dialog Box - called from: Input2 Menu

Automatic centering will center the structure in the current viewing area. This is done for each view, and any displacements entered under Constant Displacements are ignored.

In most cases, the easiest way to scale and position a drawing onto a printed or typed page is to use the frame options in the Print command or other options in the File. However, the displacements in this section can be used to position the drawing within the frame defined in those suboptions.

The displacements are used only in plotting and are not actually part of the atomic coordinates. Note that the center of rotation is not changed by these displacements - that is, the structure is always rotated about its own zero of coordinates. Thus any desired rotations should always be made before using displacements.

The Dialog Bar - Right allows centering of the viewing area on a particular projection point in the structure. Displacements made in that dialog will affect the displacements in this dialog (Centering/Displacement), and may be removed here.

The Set Center button in the Dialog Bar - Right also allows centering of the viewing area on a particular projection point in the structure.

The Scale Grid command in the Display menu is useful for showing the actual scaled location of the structure and in estimating displacements.

For perspective viewing, the projection is made from a point related to the zero of the observer coodinate system. If the displacements in Centering/Displacement are large, it may be desirable to enter offsets in the Perspective dialog, or to select Automatic Centering of the projection point in that dialog.

Note that the projection point for perspective viewing is independent of the Centering/Displacement settings, although this point may also be centered automatically (see the Perspective dialog).