Browse Prior Art Database

Character by Character Display Graphics, Labeling of Pie Charts

IP.com Disclosure Number: IPCOM000041556D
Original Publication Date: 1984-Feb-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 3 page(s) / 39K

Publishing Venue

IBM

Related People

Crehan, DT: AUTHOR

Abstract

This article relates to word processing systems having interactive display terminals, and more particularly to such systems with terminals having "character box displays", i.e., displays which form the alphanumeric characters through the generation of such characters in "character boxes" on the display and printers which print on a character by character basis. Most conventional word processing systems with interactive display terminals generally operate the display terminal as a character generation or "character box" display.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 51% of the total text.

Page 1 of 3

Character by Character Display Graphics, Labeling of Pie Charts

This article relates to word processing systems having interactive display terminals, and more particularly to such systems with terminals having "character box displays", i.e., displays which form the alphanumeric characters through the generation of such characters in "character boxes" on the display and printers which print on a character by character basis. Most conventional word processing systems with interactive display terminals generally operate the display terminal as a character generation or "character box" display. In such a display, an encoded representation of each of a font of characters is stored in a character generator memory, and as each character is to appear on the display during each display refresh cycle, the character generator memory is addressed and the coded representation of that particular character is taken from the memory and displayed in a particular designated "character box" on the display. Such character box displays are used for the construction of alphanumeric data as well as graphic data. Graphics support on word processor display terminals is increasingly becoming a requirement in today's competitive office market environment. The key challenge of character box graphics is to present high quality printed output and adequate quality display of bar, pie, and line charts while confined to a display and a print wheel printer that were intended only to output a full character cell at a time. This avoids the need for more expensive 'all- points-addressable' display and printer devices. The graphic data being made available for display purposes is data representative of various graphs used to support business or technical documents. The present algorithm relates to the formation of pie chart graphs on the display and particularly to the labeling of the slices or sectors in the pie chart. In this labeling, a number of constraints are satisfied: (1) to the extent possible, slice labels are centered outside the arc of the slice; (2) the labels are constrained to be within a number of fixed slots because of the character box environment; (3) the labels are assigned to slots so that by the time the last label is being assigned, there is always at least one slot available for it; (4) the slice labels are in the same order as the slices. Furthermore, the character box environment forces a very sparse number of label slots at the top and bottom of the pie and a very dense number on the sides; this apparatus employs a technique that counteracts this imbalance and results in a visually more pleasing labeling pattern to the user. With reference to the figure, in the character box display environment shown, the rim of the pie will approximately occupy the character boxes that are intersected by the circle. The rim is about 18 lines tall (about 36 cells wide). This results in a restricted se...