Cardenes R.,University of Valladolid |
Alberola-Lopez C.,University of Valladolid |
Ruiz-Alzola J.,University of Las Palmas de Gran Canaria |
Ruiz-Alzola J.,Canary Islands Institute of Technology
Image and Vision Computing | Year: 2010
In this paper, we present a new geodesic distance transform that uses a non-Euclidean metric suitable for non-convex discrete 2D domains. The geodesic metric used is defined as the shortest path length through a set of pixels called Locally Nearest Hidden Pixels, and manages visibility zones using bounding angles. The algorithm is designed using ordered propagation, which makes it extremely efficient and linear in the number of pixels in the domain. We have compared our algorithm with the four most similar geodesic distance transform techniques, and we show that our approach has higher accuracy and lower computational complexity. © 2009 Elsevier B.V. All rights reserved.
Castrillon M.,University of Las Palmas de Gran Canaria |
Jorge P.A.,University of Las Palmas de Gran Canaria |
Lopez I.J.,Canary Islands Institute of Technology |
Macias A.,University of Las Palmas de Gran Canaria |
And 8 more authors.
Computers and Geosciences | Year: 2011
This paper describes a wildfire forecasting application based on a 3D virtual environment and a fire simulation engine. A novel open-source framework is presented for the development of 3D graphics applications over large geographic areas, offering high performance 3D visualization and powerful interaction tools for the Geographic Information Systems (GIS) community. The application includes a remote module that allows simultaneous connections of several users for monitoring a real wildfire event. The system is able to make a realistic composition of what is really happening in the area of the wildfire with dynamic 3D objects and location of human and material resources in real time, providing a new perspective to analyze the wildfire information. The user is enabled to simulate and visualize the propagation of a fire on the terrain integrating at the same time spatial information on topography and vegetation types with weather and wind data. The application communicates with a remote web service that is in charge of the simulation task. The user may specify several parameters through a friendly interface before the application sends the information to the remote server responsible of carrying out the wildfire forecasting using the FARSITE simulation model. During the process, the server connects to different external resources to obtain up-to-date meteorological data. The client application implements a realistic 3D visualization of the fire evolution on the landscape. A Level Of Detail (LOD) strategy contributes to improve the performance of the visualization system. © 2010 Elsevier Ltd.