Computer graphics processing and selective visual display system – Display peripheral interface input device – Light pen for fluid matrix display panel
Patent
1994-07-19
1997-11-04
Saras, Steven
Computer graphics processing and selective visual display system
Display peripheral interface input device
Light pen for fluid matrix display panel
345136, 395169, G09G 522
Patent
active
056845103
ABSTRACT:
A method of displaying characters on a pixel oriented grayscale display device having a predetermined pixel resolution employing parametric, geometric glyph descriptors is disclosed. The process supports a client process that passes a request for a particular font and a physical character height for the displayed characters as well as the physical resolution expressed in pixels for unit length. A character space height value in pixels is determined and compared to selected values to determine whether the character space height in physical pixels falls into one of three distinct ranges. If within the smallest range, no hinting or grid fitting is performed and the physical pixel coordinates of a scaled glyph descriptor are scan converted using subpixel coordinates. The on subpixels within each pixel are counted to provide a grayscale value for illuminating that particular pixel. If the character space height is in the highest range, the same process is performed after the scaled glyph descriptor is hinted to physical pixel boundaries. Character space heights in the mid range are hinted to the physical pixel boundary but scan converted using a conventional scan converter for the physical pixel space. The on pixels that result from this scan conversion are then illuminated to the maximum grayscale value while off pixels from the conversion are left off. The values of the variables that define the ranges are user selectable and may be varied in response to other parameters.
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Mastering Wordperfect 5.1 & 5.2 for Windows.
Brassell Lenox H.
Kohen Eliyezer
Pathe Peter D.
Microsoft Corporation
Saras Steven
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