@Nonnull
    @Override
    public JsonObject serialize() {
        return JsonBuilder.object()
                .add("center", this.center)
                .add("radius", this.radius)
                .build();
    }
Get the circumference {@link BlockPosition} of the region
@return the {@link BlockPosition}s
helper/src/main/java/me/lucko/helper/serialize/CircularRegion.java