US 2017/0249292 A1 · CONDITIONAL DETERMINATION OF LOOKUPS IN GLYPH PROCESSING

Abstract

Conditional determination of glyph substitution (GSUB) lookups or glyph positioning (GPOS) lookups in the process of rendering a string of text as a sequence of glyphs is described. A process can include receiving a string of text comprising a sequence of characters, obtaining a sequence of glyph identifiers (IDs) corresponding to the sequence of characters, and determining that a context of the string of text satisfies a condition. Based at least in part on the context satisfying the condition, an alternate lookup can be determined and executed in lieu of a default lookup. Execution of the alternate lookup causes a GSUB operation or a GPOS operation to be performed on the sequence of glyph IDs to ultimately cause the string of text to be rendered on a display as a sequence of glyphs with a typographical feature applied thereto.

Claims20

Dependent claims

A method comprising:

receiving a string of text comprising a sequence of characters associated with a language;
obtaining a default sequence of glyph identifiers (IDs) corresponding to the sequence of characters;
applying glyph substitution rules associated with the language by:
determining that a context of the string of text satisfies a set of conditions;
in response to determining that the context satisfies the set of conditions, determining an alternate set of glyph substitution actions to use in lieu of a default set of glyph substitution actions, the alternate set of glyph substitution actions corresponding to a typographical feature that is to be applied to the string of text;
and
executing a glyph substitution action of the alternate set of glyph substitution actions, wherein executing the glyph substitution action results in a different sequence of glyph IDs;
and
causing the string of text to be rendered on a display as a sequence of glyphs corresponding to the different sequence of glyph IDs.

6 more elements

A system comprising:

one or more processors;
and
memory storing:
at least one data structure specifying a set of conditions for executing alternate lookups for purposes of glyph substitution or glyph positioning in lieu of default lookups;
and
computer-executable instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising:
receiving a string of text comprising a sequence of characters;
obtaining a sequence of glyph identifiers (IDs) corresponding to the sequence of characters;
determining, by processing the at least one data structure, that a context of the string of text satisfies a condition in the set of conditions;
in response to determining that the context satisfies the condition, determining an alternate lookup to execute in lieu of a default lookup, the alternate lookup being usable to implement a typographical feature;
executing the alternate lookup, wherein executing the alternate lookup causes a glyph substitution operation or a glyph positioning operation to be performed on the sequence of glyph IDs;
and
causing the string of text to be rendered on a display as a sequence of glyphs with the typographical feature applied to the sequence of glyphs.

10 more elements

Dependencies are inferred from the claim text.

Conditional determination of lookups in glyph processing

Life of this patent

Conditional determination of lookups in glyph processing

Life of this patent

Abstract

Claims20