Dynamic view-dependent multiresolution on a client-server
architecture
L. De Floriani, P. Magillo, F. Morando, E. Puppo
Abstract
We consider the problem of transmitting huge triangle meshes in
the context of a Web-like client-server architecture.
Approximations of the original mesh are transmitted by applying
selective refinement.
A multiresolution geometric model is maintained by the server.
A client may query the server for a mesh at an arbitrary,
continuously variable, level of detail. The client makes
repeated queries over time with different query parameters.
The server answers to queries by traversing the multiresolution
model and transmitting updates to the client, which uses them to
progressively modify a current mesh.
We study this problem in the context of a vertex-based
multiresolution model, which is a special instance of
the Multi-Triangulation (MT) \cite{Pup96,DeFPupMagGEOMOD97},
based on vertex insertion and removal.
We define a compact data structure for a vertex-based MT
which exploits the specific update rule.
We propose a dynamic algorithm for selective refinement and we discuss
in detail its implementation as a client-server application.
In order to reduce memory requirements and channel traffic, we
develop a compressed representation which allows us to express mesh
updates with a code of small size. We also address client
caching to further limit bandwidth occupancy.
Experimental results show that the Multi-Triangulation can be a key
Web technology for triangle mesh manipulation.
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