Loomis Egocentric Distance Virtual Environments 2004

Apr 28, 2011 11:46 AM  PERCEPTION OF EGOCENTRIC DISTANCE

Gogel's theory of phenomenal geometry

key piece of interest to me is on page 4 (of 14)  Presence in Virtual Environments

Hold a photo of a mountain in your hand (i paraphrase).

there is "focal awareness" of the mountain  and  "subsidiary awareness" of the picture surface.

they interfere.  the mountain only appears to be of intermediate size.

ie there is a percept conflict btwn the depicted scene etc.

easier to induce a perception of v large objects on a really big screen.

also the surrounding "picture frame"  reduces the perceived depth.

Virtual desktop systems that use conventional CRTs are like pictures and paintings

in that the CRT surface is well localized in space by the observer.

REstrictive aperture with monocular viewing or stereoscopic display reduces awareness of the display surface.

CAVE technique..  in a cube of multiple screens ...

HMD = head mounted display.   sense of immersion

as noted in Loomis 1992  complete presence is tantamount...to complete focal awreness of the sim envir.

with NO subsidiary awareness of the virtual display.

MEASURING PERCEIVED EGOCENTRIC DISTANCE

IN REAL ENVIRONMENTS

Visually perceived location and its constituents, perceived direction and perceived

egocentric distance, are aspects of conscious experience

use verbal report

open loop...   reach for object without sight of the hand; or walking to

a prev seen location.

distance estimate...  is it perception or is it what the user KNOWS.  uncontaminated.

ball throwing to target within a room;

Perception of Very Large Scale...  implications for the success of IMAX theaters etc.

appears that the field of view of our head-mounted display is not the reason for underperception

of distance in our virtual environments. We have hypothesized that

the more likely reason is that the rendering of the scenes used in our experiments

is lacking subtle but important visual cues (e.g., natural texture, and highlights).

Supporting our hypothesis are some informal observations we have made-real

environments, when viewed with our head-mounted display as it is driven by two

video cameras located at a fixed vantage point, appear much more realistic in

terms of distance and scale than our computer-synthesized virtual environments.

If this hypothesis were to be correct, it would mean that photorealistic rendering

 The second concerns phenomenology. Virtual environments that

look real in terms of scale will generally have a much greater aesthetic, cognitive,

and emotional impact. No truer is this than in connection with the rendering of

large-scale landscapes and objects. If virtual environment technology eventually

succeeds in evoking the same experience of immensity and awe that one feels

when viewing the Grand Canyon or the Egyptian Pyramids in person, it will have

achieved what large-screen projection techniques of today can only begin to elicit

at great expense.

Attachments