com.itextpdf.io.font.otf.OpenTableLookup Maven / Gradle / Ivy

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/*
    This file is part of the iText (R) project.
    Copyright (c) 1998-2023 Apryse Group NV
    Authors: Apryse Software.

    This program is offered under a commercial and under the AGPL license.
    For commercial licensing, contact us at https://itextpdf.com/sales.  For AGPL licensing, see below.

    AGPL licensing:
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see .
 */
package com.itextpdf.io.font.otf;


public abstract class OpenTableLookup {

    protected int lookupFlag;
    protected int[] subTableLocations;
    protected OpenTypeFontTableReader openReader;
    
    protected OpenTableLookup(OpenTypeFontTableReader openReader, int lookupFlag, int[] subTableLocations) {
        this.lookupFlag = lookupFlag;
        this.subTableLocations = subTableLocations;
        this.openReader = openReader;
    }
    
    public int getLookupFlag() {
        return lookupFlag;
    }

    public abstract boolean transformOne(GlyphLine line);
    
    public boolean transformLine(GlyphLine line) {
        boolean changed = false;
        line.idx = line.start;
        while (line.idx < line.end && line.idx >= line.start) {
            changed = transformOne(line) || changed;
        }
        return changed;
    }

    public boolean hasSubstitution(int index) {
        return false;
    }

    protected void readSubTables() throws java.io.IOException {
        for (int subTableLocation : subTableLocations) {
            readSubTable(subTableLocation);
        }
    }

    protected abstract void readSubTable(int subTableLocation) throws java.io.IOException;

    public static class GlyphIndexer {
        public GlyphLine line;
        public Glyph glyph;
        public int idx;

        public void nextGlyph(OpenTypeFontTableReader openReader, int lookupFlag) {
            glyph = null;
            while (++idx < line.end) {
                Glyph g = line.get(idx);
                if (!openReader.isSkip(g.getCode(), lookupFlag)) {
                    glyph = g;
                    break;
                }
            }
        }

        public void previousGlyph(OpenTypeFontTableReader openReader, int lookupFlag) {
            glyph = null;
            while (--idx >= line.start) {
                Glyph g = line.get(idx);
                if (!openReader.isSkip(g.getCode(), lookupFlag)) {
                    glyph = g;
                    break;
                }
            }
        }
    }

}