Method findShape

filters/private/hexer/BaseGrid.cpp:114–150

Walk one contiguous segment of the boundary

// Walk one contiguous segment of the boundary
void BaseGrid::findShape(HexId root)
{
    m_paths.push_back(Path(root));
    Path& path = m_paths.back();

    const Segment first(root, 0);
    Segment cur(root, 0);

    do {
        // removes possible roots that are passed over, and sets information
        // to be used in parentOrChild()
        if (cur.horizontal())
        {
            // all hexagons with non-dense neighbors at edge 0 are possible roots.
            if (cur.edge == 0)
                m_possibleRoots.erase(cur.hex);

            // if path is at edge 3, normalize to edge 0 of hex across edge 3
            // so hexagons can be processed separately in parentOrChild()
            HexId pathHex = (cur.edge == 0 ? cur.hex : edgeHex(cur.hex, 3));
            m_hexPaths.insert({pathHex, &path});

            // here we set the minimum I or J coordinate, to be used for finding
            // parents and children from m_hexPaths
            setMinCoord(pathHex);
        }
        // adds the first point of the segment to the path
        path.addPoint(findPoint(cur));
        cur = nextSegment(cur);

        // left.hex: the hexagon we would "walk into" moving clockwise from the
        // current segment.
    } while (cur != first);

    // The first point and last point must be the same.
    path.addPoint(findPoint(cur));
}

// Determine whether a path is enclosed within another
void BaseGrid::findParentPaths()