CONSTRAINT BASED AUTOMATIC TERRAIN SURFACE DESIGN

A method and system provide the ability to design a terrain surface. A triangular surface mesh representative of an existing surface is obtained. One or more constraints to control the triangular surface mesh are specified. Drainage for the triangular surface mesh is automatically determined based on the constraints. The triangular surface mesh is optimized based on the drainage and one or more design options. The optimizing modifies the triangular surface mesh to define drainage flow for the drainage.