View Management for Virtual and Augmented Reality

Blaine Bell Steven Feiner Tobias Hllerer

Presented By

Team Avatar

Damien Rompapas

Overview

Background

Summary

View Management Explained

Object Properties and Constraints

View Management Approach

My opinion

Q&A

Background on the problemWhats wrong with this interface?

Visibility => Bad

Clarity => Total Mess, Very unclear

Content occludes environment

Aim of the paper

Augmented/Virtual Reality systems with labels can be messy.

How to place labels/Annotations in 3D environments?

Key constraints: Visibility

Clarity

Implementation of View Management System Multi-User environment

Overview

Background

Summary

View Management Explained

Object Properties and Constraints

View Management Approach

My opinion

Q&A

View Management?

By View Management we mean the following:Adjusting objects in our field of view to get a

better understanding of our intended target or information in relation to the current scene

View Management?

We often make view management tasks daily, usually Subconsciously

View Management

System aims to automatically perform such tasks to maintain visual constraints on the projections of labels and objects on the viewing plane so that they

- are near relative objects

- dont occlude each other.

- satisfy applied constraints(described later)

Viewing plane?

OpenGL Theory Tutorial - http://www.falloutsoftware.com/tutorials/gl/gl0.htm

http://www.falloutsoftware.com/tutorials/gl/gl0.htm

Overview

Background

Summary

View Management Explained

Object Properties and Constraints

View Management Approach

My opinion

Q&A

Object Properties and Constraints

Display objects have properties tagged as

Controllable

Constrained

By the

User

View-Management Component

Other (tracker, simulation ect..)

Object Properties and Constraints

Constraint Types

Visibility

Position

Size

Transparency

Priority

Visibility

Whether an object can/cannot occlude other

defined objects on the viewing plane

Position

Min/Max distance from

Other Objects

Point/Area/Volume

Screen-Stabilized

Users Pose

World-Stabilized

World Pose

Size/TransparencyRange of possible sizes

- Preference towards the high end of range

Range of object transparency values

- Can be modified to minimize

Priority

Determine which order objects are occluded.

=> Useful for satisfying other constraints

Overview

Background

Summary

View Management Explained

Object Properties and Constraints

View Management Approach

My opinion

Q&A

View Management Approach

Ensure constraints in dynamic environment.

Adjust position &

size of objects at

every frame

View-Plane Representation/Visible Surface Determination

Each 3D Object: Upright rectangular extent of its projection on the view plane. (largest empty-space rectangles), Sorted using BSP Tree for visibility representation.

Largest empty-space rectanglesGiven an incrementally specified input set of possibly overlapping, axis-aligned, rectangles. It automatically maintains an efficient representation of the dual of this set of rectangles: the area that has not been rendered.

This is noted as the Largest empty space rectangle

Any object rendered in this region will not occlude other objects

Each largest rectangle lies along the outer edge of any input rectangle.

Suppose that:axis-aligned rectangular extents of the projections of all scene objects have been added to the representation, and that we are given the extent A of some new objects projection.

Largest empty-space rectanglesMultiple empty-space rectangles

can be merged to create a larger

Empty-space rectangle

BSP TreeBest known in the video game Doom

Standard Binary Tree, Sort/Search for polytypes n n-dimensional space

Tree as whole represents entire state

Each node stores a Hyperplane, dividing the space into two halves

Internal & External Labelling

Area Feature Label/Annotations

Temporal Continuity

Each frame is computed independently.Frames computed independently result in discontinuous changes in:- Size- Position

This can result in jumpy andconfusing transitions between states.

Temporal Continuity

Steps to solve using previous frame

- State Hysteresis

- Positional Stability

- Interpolation

State HysteresisThere are several situations in which objects may change state, resulting in a discrete visual change, such as from an internal label to external one, or from being displayed to not being displayed.

They borrow the approach modify the definitions of: Absolute minimum Size (absMin) Sustained minimum Size (min)

Positional Stability

To keep the labels clear, They are placed without opportunity of jitter.

Two situations:

Best Possible Layout independent of

the previous layout.

Closest t Possible layout to previous

layout.

For Label L attached to Object A=> L Uses largest available space

within A

L Uses largest available space

outside A

Interpolation

To minimize the effect of discontinuous jumps

Interpolate the values of all constraints between frames

Implementation

HardwareCPU: 1.4 GHz Pentium 4RAM: 512 MB RamGraphics: SONICBlue FireGL 2

SoftwareOS: Windows 2KView Management: JavaRendering: Java 3DView Management/RenderingSeperated.

Overview

Background

Summary

View Management Explained

Object Properties and Constraints

View Management Approach

My opinion

Q&A

Fantastic

Very General Problem

The paper goes in-depth on expressing this with previous work.

Very applicable (Surprised current systems dont implement)

Can improve on bad UI Representation: Second Slide.

Great

Uses the world in miniature (WIM) to assist in orientation and labelling environment

Labels Jump between real world and world in miniature

Great

Provides relation to research and human habits to generate overview, easily able to understand context of the problem.

My favorite paragraph in the paper.

In the real world, we make simple view management decisions routinely, and often subconsciously. For example, we push aside a centerpiece to enable eye contact with others at dinner, or we hold a city guidebook so that we can read a relevant section, while simultaneously viewing an historic building that it describes as we pass by on a bus

Great

Detailed Description of the method involved, extends on research from 2D environments

Open to re-implementation

(Source code not available, explained later)

Good

Paper does show one comparison between their labelling and other typical labelling methods.

(Left to right: Nave,Suppression, View Management)

(Why is this the only one though?)

Good

Wide Variety of references, Some of them are good papers! B. Bell and S. Feiner. Dynamic space management for

user interfaces. In Proc. ACM UIST 2000

Many parts of this paper are included and extended in this research.

References include 2D environment, 3D, Human Behaviour and Analysis, Even a book!

A famous book: Computer Graphics: Principles and Practice

Strange

Lacks teaser image description,

Instead referred in Introduction through repeat of images.

Most papers in the same year journal (I checked about 30) didnt have a teaser image, very strange

Doubtful

Lack of Usability Studies

They talk about this in future work

Our goal is to compare performance with and without different versions of the view-management component on modeling tasks in cluttered environments that would appear to be good candidates for its use.

They already have a working system

Doubtful

Some parts of the paper were hard to understand

Far too wordy, slightly over-explained.

Requires background knowledge

Had to read some of the referenced papers before beginning to understand

Diagrams can be better explained

Doubtful

The video shown was recorded using a HMD on a tripod.

Prevent rapid shaking

How Stable the positional stability is

Bad

They very briefly talked about, but didnt show the GUI used for adding/creating annotations. (As far as the paper is aware) We dont know how difficult it is to add

these annotations, it could all be text-based?

If its complex, it could make the system useless for most use cases.

William Chiong and Yoav Hirsch developed the software infrastructure that we used to create a GUI for specifying user parameters.

On the previous note

This video below only briefly shows the interface, which looks complicated. (Live Demonstration)

Sad

This system is so good! Why arent we using it?

Possibilities Computation Power

Very Low cost, running on low powered (Ancient) machine

Annotation Creation GUIWe dont know how complex/time consuming for

the creation of annotations.

Live annotation creationDidnt demonstrate On The Fly annotations

Paper Mentions Funded By ONR ContractsAmerican Naval Research CompanyMight be top-secret (In which case, why a paper?)

Related Observation

The Labelling system generated using this view-management system tends to favor the outside edges of the screen, something that many user interfaces already do.

Why is it related?

If you added many more external labels to the Journalism tag,

Wouldnt we end up with a cluttered and confusing labelledenvironment, akin to my second slide?

The problem may be unavoidable.

Another personal opinion

This paper really isnt a Research Paper Doesnt present Hypothesis/User

Study etc.

Rather it presents a Novell implementation/Solution to a problem.

It doesnt stress a significant improvement over other methods However it is clearly visible.

Final Opinion

What makes a system good and easy to use can depend entirely on how information is

represented on the screen as well as the quality, too much can be intimidating and confusing, too

little is a waste of space.

This paper opens up a new automated method to represent such information .

Discussion Points (Q&A) Fantastic

Very general problem

Great Detailed Description of the method involved

Good Wide Variety of references

Strange Lacks teaser image description

Doubtful Lack of Usability Studies Paper hard to understand

Bad GUI not explained in detail

Sad We dont use the system.