Perceptually-Adaptive Collision Detection for Real-time Computer Animation
File Type:
PDFItem Type:
DoctoralDoctor of Philosophy (Ph.D.)
Date:
1999Author:
Download Item:
Abstract:
The aim of interactive animation systems is to create an exciting and real experience
for viewers, to give them a feeling of immersion, of "being there". The tendency in the
past has been to attempt to achieve this by matching as closely as possible the
physics of the real world, with varying degrees of success. However, it is the human
visual system that receives and interprets the visual cues from the surrounding
environment, and it ultimately determines what we perceive. Therefore, we must look
beyond the laws of physics to find the secret of reproducing visual reality. In interactive animation applications such as VR or games, it cannot be predicted in
advance how a user or the entities in a virtual world will behave, so the animation
must be created in real-time. There are many bottlenecks in such systems, collision
detection being a major one. A trade-off between detection accuracy and speed is
necessary to achieve a high and constant frame-rate. However, it is possible to
reduce perceived inaccuracy by taking perceptual factors into account, and also by
estimating where on the screen a viewer is looking, possibly using an eye-tracking
device, or by attaching more importance to certain objects in a scene, or to regions of
the screen. In this thesis we present the first perceptually-adaptive collision detection algorithm.
New collision scheduling strategies are also presented and evaluated, along with a
new interruptible algorithm to test for the intersection between two sphere trees. A
model of human visual perception of collisions is developed, based on twodimensional
measures of eccentricity and separation. The model is validated by
performing psychophysical experiments, in the first study of its kind. We demonstrate
the feasibility of using this model as the basis for perceptual scheduling of
interruptible collision detection in a real-time animation of large numbers of
homogeneous objects. The user's point of fixation may be either tracked or
estimated. By using a priority queue scheduling algorithm, perceived collision
inaccuracy was significantly improved. The ideas presented here are applicable to
other tasks where the processing of fine detail leads to a computational bottleneck.
Author: O'SULLIVAN, CAROL ANN
Advisor:
Collins, StevenType of material:
DoctoralDoctor of Philosophy (Ph.D.)
Collections
Availability:
Full text availableKeywords:
Computer ScienceMetadata
Show full item recordLicences: