In the field of terrain visualization, the most efficient tool for real time rendering of complex landscape is level of detail (LOD) technique. In this paper, an optimization quadtree-based algorithm for dynamic generation continuous levels of a given complex landscape in real time is developed. In this algorithm, the conception of view-dependent is introduced, the fast searching algorithm for ...

In this paper we present algorithms for performing adaptive vector quantization with memory. By using memory between adjacent blocks which are encoded, we can take advantage of the correlation between adjacent blocks of pixels to reduce redundancy. We use either nite state vector quantization or predictive vector quantization to provide the memory. To further improve performance by exploiting n...

The paper presents a novel method for encoding the linear quadtree of a given image. In this method, the pixels of the image are scanned in row major order. In each encountered pixel, the result codes in the linear quadtree are updated simultaneously in real time. The linear quadtree is thus obtained after all pixels are processed. This method is quite different from those in previous studies, ...

A method, termed approximate splitting, is proposed to model the node distribution that results when the PR quadtree is used to store point data drawn from a uniform distribution. This method can account for the aging and phasing phenomena which are common in most hierarchical data structures. Approximate splitting is also shown to be capable of being adapted to model the node distribution of t...

We explore the applicability of the quadtree encoding method to the run-time MPI collective algorithm selection problem. Measured algorithm performance data was used to construct quadtrees with different properties. The quality and performance of generated decision functions and in-memory decision systems were evaluated. Experimental data shows that in some cases, a decision function based on a...

SAND is a spatial database and information browser system developed at University of Maryland which supports 2D and 3D data models. The experience in extending SAND to include a spherical data model thereby enabling SAND to perform spatial queries on spherical data and to browse their results in an incremental manner is described. The focus is on the issues that arise in adding a spherical data...

Many algorithms exist for producing quality meshes when the input point cloud is known a priori. However, modern finite element simulations and graphics applications need to change the input set during the simulation dynamically. In this paper, we show a dynamic algorithm for building and maintaining a quadtree under insertions into and deletions from an input point set in any fixed dimension. ...