diff --git a/src/lib/tin.cpp b/src/lib/tin.cpp
index 85e3ef3..54034a3 100644
--- a/src/lib/tin.cpp
+++ b/src/lib/tin.cpp
@@ -10,23 +10,6 @@
  * Copyright (c) 2021-2031 Yi Zhang (zhangyiss@icloud.com)
  * All rights reserved.
  *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
  */
 
 #include "tin.h"
@@ -725,3 +708,19 @@ void dem2tin(const std::vector<double> &dem, double xmin, double xmax, double ym
 	}
 	return;
 }
+
+/**
+ * @brief      Generate the TIN from random DEM points
+ * 
+ * @param dem               Input DEM points
+ * @param out_verts         The output vector of vertex's pointers. The user need to destroy the memories allocated by the function before destroy the vector
+ * @param      out_tris     The output vector of triangle's pointers. The user need to destroy the memories allocated by the function before destroy the vector
+ * @param[in]  maxi_err     Threshold to quit the algorithm. The default is 1e-0
+ * @param[in]  outline_poly If this pointer is not NULL, Cut triangle outside the polygon.
+ * @param[in]  err_records  If this pointer is not NULL, record maximal error values after each insertion of vertex.
+ */
+void rnd2tin(const std::vector<dem_point> &dem, std::vector<vertex2dc*> &out_verts, std::vector<triangle*> &out_tris, 
+	double maxi_err, std::vector<dem_point> *outline_poly, std::vector<double> *err_records)
+{
+	return;
+}
diff --git a/src/lib/tin.h b/src/lib/tin.h
index b298fd8..54b0715 100644
--- a/src/lib/tin.h
+++ b/src/lib/tin.h
@@ -10,23 +10,6 @@
  * Copyright (c) 2021-2031 Yi Zhang (zhangyiss@icloud.com)
  * All rights reserved.
  *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
  */
 
 #ifndef _TIN_DELAUNAY_H
@@ -220,4 +203,18 @@ void dem2tin(const std::vector<double> &dem, double xmin, double xmax, double ym
 	double dx, double dy, std::vector<vertex2dc*> &out_verts, std::vector<triangle*> &out_tris, 
 	double maxi_err = 1e-0, std::vector<double> *err_records = nullptr);
 
+/**
+ * @brief      Generate the TIN from random DEM points
+ * 
+ * @param dem               Input DEM points
+ * @param out_verts         The output vector of vertex's pointers. The user need to destroy the memories allocated by the function before destroy the vector
+ * @param      out_tris     The output vector of triangle's pointers. The user need to destroy the memories allocated by the function before destroy the vector
+ * @param[in]  maxi_err     Threshold to quit the algorithm. The default is 1e-0
+ * @param[in]  outline_poly If this pointer is not NULL, Cut triangle outside the polygon.
+ * @param[in]  err_records  If this pointer is not NULL, record maximal error values after each insertion of vertex.
+ */
+void rnd2tin(const std::vector<dem_point> &dem, std::vector<vertex2dc*> &out_verts, 
+	std::vector<triangle*> &out_tris, double maxi_err = 1e-0, std::vector<dem_point> *outline_poly = nullptr, 
+	std::vector<double> *err_records = nullptr);
+
 #endif // _TIN_DELAUNAY_H
\ No newline at end of file