Examples with VerticalMetricsTable org.apache.fontbox.ttf.VerticalMetricsTable used on opensource projects

Example 1 with VerticalMetricsTable

use of org.apache.fontbox.ttf.VerticalMetricsTable in project pdfbox by apache.

the class PDCIDFontType2Embedder method buildVerticalMetrics.

/**
 * Builds vertical metrics with a custom CIDToGIDMap (for embedding font subset).
 */
private void buildVerticalMetrics(Map<Integer, Integer> cidToGid) throws IOException {
    if (!buildVerticalHeader(cidFont)) {
        return;
    }
    float scaling = 1000f / ttf.getHeader().getUnitsPerEm();
    VerticalHeaderTable vhea = ttf.getVerticalHeader();
    VerticalMetricsTable vmtx = ttf.getVerticalMetrics();
    GlyphTable glyf = ttf.getGlyph();
    HorizontalMetricsTable hmtx = ttf.getHorizontalMetrics();
    long v_y = Math.round(vhea.getAscender() * scaling);
    long w1 = Math.round(-vhea.getAdvanceHeightMax() * scaling);
    COSArray heights = new COSArray();
    COSArray w2 = new COSArray();
    int prev = Integer.MIN_VALUE;
    // Use a sorted list to get an optimal width array
    Set<Integer> keys = new TreeSet<>(cidToGid.keySet());
    for (int cid : keys) {
        // Unlike buildWidths, we look up with cid (not gid) here because this is
        // the original TTF, not the rebuilt one.
        GlyphData glyph = glyf.getGlyph(cid);
        if (glyph == null) {
            continue;
        }
        long height = Math.round((glyph.getYMaximum() + vmtx.getTopSideBearing(cid)) * scaling);
        long advance = Math.round(-vmtx.getAdvanceHeight(cid) * scaling);
        if (height == v_y && advance == w1) {
            // skip default metrics
            continue;
        }
        // c [w1_1y v_1x v_1y w1_2y v_2x v_2y ... w1_ny v_nx v_ny]
        if (prev != cid - 1) {
            w2 = new COSArray();
            // c
            heights.add(COSInteger.get(cid));
            heights.add(w2);
        }
        // w1_iy
        w2.add(COSInteger.get(advance));
        long width = Math.round(hmtx.getAdvanceWidth(cid) * scaling);
        // v_ix
        w2.add(COSInteger.get(width / 2));
        // v_iy
        w2.add(COSInteger.get(height));
        prev = cid;
    }
    cidFont.setItem(COSName.W2, heights);
}