Julien Lacoste, Tamy Boubekeur, Bruno Jobard and hristophe Schlick ACM Graphite 2007
Left: simplified mesh of 15K triangles.
Middle: an octree is built around this mesh to adaptively sample
and store the normal field of the high resolution version of the
mesh. Right: the simplified mesh is normal mapped via a special
GPU traversal of the octree cells encoded in a 2D texture. The
operation does not requires 2D parametrization of the mesh.
Abstract
Because of their geometric complexity, high resolution 3D models, either
designed in high-end modeling packages or acquired with range
scanning devices, cannot be directly used in applications that
require rendering at interactive framerates. One clever method to
overcome this limitation is to perform an \emph{appearance
preserving geometry simplification}, by replacing the original
model with a low resolution mesh equipped with high resolution
normal maps. This process visually preserves small scale features
from the initial geometry, while only requiring a reduced set of
polygons. However, this conversion usually relies on some kind of
global or piecewise parameterization, combined with the generation
of a texture atlas, a process that is computationally expensive
and requires precise user supervision. In this paper, we propose
an alternative method in which the normal field of a high
resolution model is adaptively sampled and encoded in an
octree-based data structure, that we call \emph{appearance
preserving octree-texture} ({\bf APO}). Our main contributions are:
a {\bf normal-driven octree generation}, a {\bf compact encoding} and an
{\bf efficient look-up algorithm}. Our method is efficient,
totally automatic, and avoids the expensive creation of a
parameterization with its corresponding texture atlas.
Resources
Publication:
Video:
BibTex Reference: @InProceedgins{Lacoste:2007:APO,
author = {Julien Lacoste and Tamy Boubekeur and Bruno Jobard and Christophe Schlick},
title = {Appearance Preserving Octree-Textures},
booktitle ={ACM Graphite},
year = {2007},
pages = {87-93},
}
Demo:
A JOGL Applet is available here. It implements a remote version of Appearance Preserving Octree-Textures. The specific issues related to online visualization are discussed in Progressive Transmission of Appearance Preserving Octree-Textures, Lacoste et al., ACM Web3D 2008.
