view src/share/native/sun/font/layout/AlternateSubstSubtables.cpp @ 13703:64b55ae060e8

8227129: Better ligature for subtables Reviewed-by: bae
author mbalao
date Tue, 24 Sep 2019 19:07:02 -0300
parents a993ef3e9d23
children
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/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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 General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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/*
 *
 * (C) Copyright IBM Corp. 1998-2004 - All Rights Reserved
 *
 */

#include "LETypes.h"
#include "LEGlyphFilter.h"
#include "OpenTypeTables.h"
#include "GlyphSubstitutionTables.h"
#include "AlternateSubstSubtables.h"
#include "GlyphIterator.h"
#include "LESwaps.h"

U_NAMESPACE_BEGIN

le_uint32 AlternateSubstitutionSubtable::process(const LEReferenceTo<AlternateSubstitutionSubtable> &base,
                                       GlyphIterator *glyphIterator, LEErrorCode &success, const LEGlyphFilter *filter) const
{
    if (LE_FAILURE(success)) {
        return 0;
    }

    // NOTE: For now, we'll just pick the first alternative...
    LEGlyphID glyph = glyphIterator->getCurrGlyphID();
    le_int32 coverageIndex = getGlyphCoverage(base, glyph, success);

    if (coverageIndex >= 0 && LE_SUCCESS(success)) {
        le_uint16 altSetCount = SWAPW(alternateSetCount);

        if (coverageIndex < altSetCount) {
            const LEReferenceToArrayOf<Offset>
                arrayRef(base, success, alternateSetTableOffsetArray, altSetCount);
            if (!LE_SUCCESS(success)) return 0;

            Offset alternateSetTableOffset = SWAPW(arrayRef.getObject(coverageIndex, success));
            if (!LE_SUCCESS(success)) return 0;

            const LEReferenceTo<AlternateSetTable> alternateSetTable(base, success,
                                  (const AlternateSetTable *) ((char *) this + alternateSetTableOffset));
            if (!LE_SUCCESS(success)) return 0;
            TTGlyphID alternate = SWAPW(alternateSetTable->alternateArray[0]);

            if (filter == NULL || filter->accept(LE_SET_GLYPH(glyph, alternate), success)) {
                glyphIterator->setCurrGlyphID(SWAPW(alternateSetTable->alternateArray[0]));
            }

            return 1;
        }

        // XXXX If we get here, the table's mal-formed...
    }

    return 0;
}

U_NAMESPACE_END