Terrains and other geometric models have been traditionally stored locally. Their remote access presents the characteristics that are a combination of file serving and realtime streaming like audio-visual media. This paper presents a terrain streaming system based upon a client server architecture to handle heterogeneous clients over low-bandwidth networks. We present an efficient representatio...

We study the complexity and the I/O-efficient computation of flow on triangulated terrains. We present an acyclic graph, the descent graph, that enables us to trace flow paths in triangulations i/o-efficiently. We use the descent graph to obtain i/o-efficient algorithms for computing river networks and watershed-area maps in O(Sort(d + r)) i/o’s, where r is the complexity of the river network a...

We consider the problem of finding shortest paths on the surface of uncertain terrains. In this paper, a terrain is a triangulated 2D surface in 3D such that every vertical line intersects the surface at most once. Terrains of this type are used to represent, for example, a piece of the earth’s surface, and are typically inexact. We model their uncertainty by allowing the terrain vertices to ha...

In this paper, we address the problem of terrain classification using a technically blind hexapod walking robot. The proposed approach is built on top of the existing method based on analysis of the feedback from the robot’s actuators and the desired trajectory. The formed method uses features for the Support Vector Machine classification method that assumes a regular time-invariant gait to con...

A multi-visibility map is the subdivision of the domain of a terrain into different regions that, according to different criteria, encode the visibility with respect to a set of view elements. We present an algorithm for computing approximate multi-visibility maps for a terrain, modeled as a TIN, with respect to a set of view segments. Our approach is based on an algorithm that reconstructs an ...

rivers are important water resources for human life, but sometimes cause irreparable damages. the flood plains are fertile terrains which are endangered by flood. flood hazard mapping is one of the basic methods in flood fighting. in order to decline flood damages, the simulation of the hydraulic behavior of the rivers during flood occurrence is very important. in this study, areas that are flo...

We study the problem of matching two polyhedral terrains, where one can be changed vertically by a linear transformation of the third coordinate (scaling and translation). We give an algorithm that minimizes the maximum distance over all linear transformations in O(npolylog n) expected time. We also study matching two 1-dimensional terrains, and give a (1+ ε)-approximation algorithm for minimiz...

Computer games, TV series, movies, simulators, and many other computer graphics applications use external scenes where a realistic looking terrain is a vital part of the viewing experience. Creating such terrains is a challenging task. In this paper we propose a method that generates realistic virtual terrains by simulation of hydraulic and thermal erosion on a predefined height field terrain. ...

An imprecise 1-dimensional terrain is an x-monotone polyline where the y-coordinate of each vertex is not fixed but only constrained to a given interval. In this paper we study four different optimization measures for imprecise 1-dimensional terrains, related to obtaining smooth terrains. In particular, we present algorithms to minimize the largest and total turning angle, and to maximize the s...