Class GlyphSubstitutionState


  • public class GlyphSubstitutionState
    extends GlyphProcessingState

    The GlyphSubstitutionState implements an state object used during glyph substitution processing.

    This work was originally authored by Glenn Adams (gadams@apache.org).

    • Constructor Detail

      • GlyphSubstitutionState

        public GlyphSubstitutionState()
        Construct default (reset) glyph substitution state.
      • GlyphSubstitutionState

        public GlyphSubstitutionState​(GlyphSequence gs,
                                      java.lang.String script,
                                      java.lang.String language,
                                      java.lang.String feature,
                                      ScriptContextTester sct)
        Construct glyph substitution state.
        Parameters:
        gs - input glyph sequence
        script - script identifier
        language - language identifier
        feature - feature identifier
        sct - script context tester (or null)
      • GlyphSubstitutionState

        public GlyphSubstitutionState​(GlyphSubstitutionState ss)
        Construct glyph substitution state using an existing state object using shallow copy except as follows: input glyph sequence is copied deep except for its characters array.
        Parameters:
        ss - existing positioning state to copy from
    • Method Detail

      • reset

        public GlyphSubstitutionState reset​(GlyphSequence gs,
                                            java.lang.String script,
                                            java.lang.String language,
                                            java.lang.String feature,
                                            ScriptContextTester sct)
        Reset glyph substitution state.
        Overrides:
        reset in class GlyphProcessingState
        Parameters:
        gs - input glyph sequence
        script - script identifier
        language - language identifier
        feature - feature identifier
        sct - script context tester (or null)
        Returns:
        this instance
      • setAlternates

        public void setAlternates​(int[] alternates)
        Set alternates indices.
        Parameters:
        alternates - array of alternates indices ordered by coverage index
      • getAlternatesIndex

        public int getAlternatesIndex​(int ci)
        Obtain alternates index associated with specified coverage index. An alternates index is used to select among stylistic alternates of a glyph at a particular coverage index. This information must be provided by the document itself (in the form of an extension attribute value), since a font has no way to determine which alternate the user desires.
        Parameters:
        ci - coverage index
        Returns:
        an alternates index
      • putGlyph

        public void putGlyph​(int glyph,
                             CharAssociation a,
                             java.lang.Object predication)
        Put (write) glyph into glyph output buffer.
        Parameters:
        glyph - to write
        a - character association that applies to glyph
        predication - a predication value to add to association A if predications enabled
      • putGlyphs

        public void putGlyphs​(int[] glyphs,
                              CharAssociation[] associations,
                              java.lang.Object predication)
        Put (write) array of glyphs into glyph output buffer.
        Parameters:
        glyphs - to write
        associations - array of character associations that apply to glyphs
        predication - optional predicaion object to be associated with glyphs' associations
      • getOutput

        public GlyphSequence getOutput()
        Obtain output glyph sequence.
        Returns:
        newly constructed glyph sequence comprised of original characters, output glyphs, and output associations
      • apply

        public boolean apply​(GlyphSubstitutionSubtable st)
        Apply substitution subtable to current state at current position (only), resulting in the consumption of zero or more input glyphs, and possibly replacing the current input glyphs starting at the current position, in which case it is possible that indexLast is altered to be either less than or greater than its value prior to this application.
        Parameters:
        st - the glyph substitution subtable to apply
        Returns:
        true if subtable applied, or false if it did not (e.g., its input coverage table did not match current input context)
      • apply

        public boolean apply​(GlyphTable.RuleLookup[] lookups,
                             int nig)
        Apply a sequence of matched rule lookups to the nig input glyphs starting at the current position. If lookups are non-null and non-empty, then all input glyphs specified by nig are consumed irregardless of whether any specified lookup applied.
        Parameters:
        lookups - array of matched lookups (or null)
        nig - number of glyphs in input sequence, starting at current position, to which the lookups are to apply, and to be consumed once the application has finished
        Returns:
        true if lookups are non-null and non-empty; otherwise, false
      • applyDefault

        public void applyDefault()
        Apply default application semantices; namely, consume one input glyph, writing that glyph (and its association) to the output glyphs (and associations).
        Overrides:
        applyDefault in class GlyphProcessingState