Function get_walk_group

plugins/burrow.cpp:481–496

ramp tops inherit walkability group of the tile below

// ramp tops inherit walkability group of the tile below
static uint16_t get_walk_group(const df::coord & pos) {
    df::tile_designation *des = Maps::getTileDesignation(pos);
    if (!des || des->bits.hidden)
        return 0;
    uint16_t walk = Maps::getWalkableGroup(pos);
    if (walk)
        return walk;
    if (auto tt = Maps::getTileType(pos)) {
        if (tileShape(*tt) == df::tiletype_shape::RAMP_TOP) {
            df::coord pos_below(pos);
            --pos_below.z;
            walk = Maps::getWalkableGroup(pos_below);
        }
    }
    return walk;
}

static bool is_tree(const df::tiletype *tt) {
    return tileMaterial(*tt) == tiletype_material::TREE;