Circles and Splines in Annotations

As expected with its introduction in Release 3.0, the concept of annotations has quickly become a widely used feature of EMME/2. In order to add even more possibilities of use to the annotations, two new types of graphic elements have been added in Release 4.0, complementing the already existing types "vector chain" and "text":

CIRCLE:

A circle is created on the screen by typing the letter "o" to define the center of the circle and a space character to identify any point on the perimeter of the circle. In the annotation file format (for those users interested in creating an annotation file externally), a circle is defined by a move command "m" to the center point, followed by an "o" command defining a point on the perimeter of the circle.

SPLINE:

A spline curve, i.e. a smooth curve connecting a set of given points, can be defined by entering the letter "j" to define the first point of the spline and then define all subsequent points by use of the space character. Note that, as is the case with splines in demarcations (see manual IV-1.41), the first and the last point of the spline are used only to indicate the (hidden) continuation of the curve. Thus, only after the forth spline point has been entered the first section of the spline is actually drawn on the screen. In the annotation file format, a spline is represented by an initial move command "m", followed by a sequence of at least 3 "j" commands, each defining one point of the spline curve.

Both circles and splines are drawn using the currently defined color and line pattern.

Since the type of spline curves used in the annotations are exactly the same as those used in demarcations, it is now very easy to transform existing demarcations into annotations. Note, however, that the different symbols used with demarcations are not directly available with annotations.