A data processing system for displaying graphical symbols.

摘要

A data processing system processes a data stream based on the structure of a font file which can be varied by a user or application of the processing system. The font file not only contains the pel patterns for a range of graphical symbols, but it also contains the rules for interpreting a data stream having a particular syntax. The rules for interpreting a data stream are referred to as the processing model for the data stream. The structure of the font file contains an index array to the range of graphical symbols. Each byte in the data stream is used to generate an index into the index array. In each element of the index array there is a value and control bits. The control bits indicate whether the value is an offset to a graphical symbol or whether the value is a modifier. If the value is a modifier, it is used to increment the next sequential data byte in the data stream through the range of graphical symbols. The modifiers can be use recursively to access an unlimited number of graphical symbols.