void GENERIC_LOOP_ALGO()

in h3_polygonAlgos.h [151:196]

• 36 lines of code
• 12 McCabe index (conditional complexity)

void GENERIC_LOOP_ALGO(bboxFrom)(const TYPE *loop, BBox *bbox) {
    // Early exit if there are no vertices
    if (IS_EMPTY(loop)) {
        *bbox = (BBox){0};
        return;
    }

    bbox->south = DBL_MAX;
    bbox->west = DBL_MAX;
    bbox->north = -DBL_MAX;
    bbox->east = -DBL_MAX;
    double minPosLng = DBL_MAX;
    double maxNegLng = -DBL_MAX;
    bool isTransmeridian = false;

    double lat;
    double lng;
    LatLng coord;
    LatLng next;

    INIT_ITERATION;

    while (true) {
        ITERATE(loop, coord, next);

        lat = coord.lat;
        lng = coord.lng;
        if (lat < bbox->south) bbox->south = lat;
        if (lng < bbox->west) bbox->west = lng;
        if (lat > bbox->north) bbox->north = lat;
        if (lng > bbox->east) bbox->east = lng;
        // Save the min positive and max negative longitude for
        // use in the transmeridian case
        if (lng > 0 && lng < minPosLng) minPosLng = lng;
        if (lng < 0 && lng > maxNegLng) maxNegLng = lng;
        // check for arcs > 180 degrees longitude, flagging as transmeridian
        if (fabs(lng - next.lng) > M_PI) {
            isTransmeridian = true;
        }
    }
    // Swap east and west if transmeridian
    if (isTransmeridian) {
        bbox->east = maxNegLng;
        bbox->west = minPosLng;
    }
}