Many GOPRR types (or their subtypes) use graphical representations in the
MetaEdit+ environment. These types are projects, graphs, objects, roles,
relationships and queries. Many MetaEdit+ tools, e.g. Draw Window, Matrix
Editor and Graphical Query Editor, use these graphical representations for
displaying the GOPRR types.
To allow an easy definition of these graphical symbols and linking to their
conceptual counterparts, we have developed the Symbol Editor. It is a simple
vector graphics editor with the capability to store a picture as a default
representation of some GOPRR type.
In developing the Symbol Editor we had the following objectives:
symbol definitions can contain any number of different types of shapes
(ellipse, rectangle, rounded rectangle, line, polygon, text and bitmap)
each shape can have different attributes (colour, width, brush)
a symbol can have labels that show its GOPRR type's property values
users can save shapes to GOPRR type, or to a symbol library
Users can now define complex shapes with Symbol Editor and save them to a GOPRR
type or to the symbol library. All the basic shape types are supported and each
of them can have different kinds of attributes. GOPRR type's properties can be
defined to be part of a symbol's representation using labels. When a GOPRR
object changes its property value, the labels automatically display this new
value.
In the future symbols will be changed to support individual scaling, multiline
labels with automatic size adjustment, and rotating. The ability to change a
symbol's representation according to the representation rules attached to a
type will also be developed