VISUAL EDITING SYSTEM INCORPORATING SELECTABLE LETTER SPACING DISPLAY AND ASSOCIATED SCALE DISPLAY

摘要

A data composing, editing, formatting and display system for use by composers of business documents and quality printed graphics. A cathode-ray tube display is utilized to display text characters imputed by a secondary media reader in a manner analogous to a display of a page of typed data on a typewriter. The number of words of text which appear on each line of displayed text between margin boundaries are optimized. Additional text may be inserted or deleted at any point in the displayed text or the margin boundaries can be altered resulting in the displayed text shifting to accommodate the additional text or new boundaries. Text shifting results in reoptimization of the displayed lines without resultant loss of word integrity or paragraph definition. Operator controls are actuable to effect display of the displayed characters in either standard spacing or in proportional spacing. When standard spacing is specified, each character has the same escapement value. When proportional spacing is specified, the escapement value of the character varies in accordance with the character width. Since the average character width in proportional spacing is less than the average character width of standard spacing characters, a shift from standard spacing to proportional spacing could result in additional space located at the end of each line of displayed text. The operator may thereafter specify an optimization operation to maximize the number of words of proportionally spaced characters which appear within the margin boundaries on each display line. A set of scales corresponding to the escapement value selected can selectively be displayed adjacent to the text characters to inform the operator of the space that the displayed line will occupy on a printed document. Additionally, a partial adjust operation enables the operator to align the text on even pica positions when shifting from standard spacing to proportional spacing.