private com.google.protobuf.RepeatedFieldBuilder<
          org.box2d.proto.Box2D.PbVec2, org.box2d.proto.Box2D.PbVec2.Builder, org.box2d.proto.Box2D.PbVec2OrBuilder> 
          getPointsFieldBuilder() {
        if (pointsBuilder_ == null) {
          pointsBuilder_ = new com.google.protobuf.RepeatedFieldBuilder<
              org.box2d.proto.Box2D.PbVec2, org.box2d.proto.Box2D.PbVec2.Builder, org.box2d.proto.Box2D.PbVec2OrBuilder>(
                  points_,
                  ((bitField0_ & 0x00000010) == 0x00000010),
                  getParentForChildren(),
                  isClean());
          points_ = null;
        }
        return pointsBuilder_;
      }