[PDF] - Computers C.W. Johnson, Univ ersit y of Glasgo w, Glasgo w, PDF Document

SLIDE 1 Computers C.W. Johnson, Univ ersit y

f

Glasgo w, Glasgo w, G12 8QQ. Scotland. johnson@dcs.gla.ac.uk, h ttp://www.dcs.gla .a c.uk/ johnso n Octob er 2001 CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001 1

SLIDE 2 Intro duction

Logical

and physical I/O devices.

Dialogue

st yles:

text;

fo rms; menus; graphics.

WYSIWYG,

Metapho r and Direct Manipulation.

Breakdo

wn. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 3 Input Devices

Several

physical devices implement a logical device. Ac kno wledgemen t: Microsoft and Ericsson

T

ext input implemented b y: { k eyb

a

rds, sp eech recognition, handwriting, gloves. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 4 Input Devices

P
inting

implemented b y: { mice, touch-screens, track er balls, ey e-tracking.

Cameras

also used to p rovide input: { automatic facial recognition using feature extraction.

P

eople a re themselves b ecoming input devices: { c

ntext

awar e systems track the user's lo cation. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 5 Output Devices

Printed
utput:
laser

p rinters; ink-jets; impact and thermal p rinters. Ac kno wledgemen t: P anasonic and NEC

Graphical
utput:
CRT
r

LCD displa ys; p rojecto rs. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 6 Output Devices

Audio
utput:
stereo/surround

sp eak ers; headphones.

P
tential

p roblems:

ea

rcons

r

audito ry icons?

pitch/timb

re, relationship to music? CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 7 Virtual Realit y

Displa

ys: helmet mounted

r

p rojection.

Input

devices: head and b

dy

tracking. Ac kno wledgemen t: www.vrealities.com

Many

usabilit y issues:

most

systems lack fo rce feedback;

stresses
n

b

dy

holding a 3D p

sition;
pa

rallax p roblems and nausea. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 8 Virtual Realit y

F
rce

feedback

r

haptics:

jo

ysticks; moto r-driven feedback; The Bed;

some
f

these a re input and

utput

devices.

Financial

exp ense, relaibilit y etc. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 9 Desktop Virtual Realit y

T

echnologies:

QuicktimeVR;
Virtual

Realit y Ma rkup Language;

DirectX

and Spatial Audio.

Many

usabilit y issues:

3D

spatial p

sitioning

with 2D devices;

navigation

and w a y-nding is ha rd;

animation
f

environments requires scripts;

VRML

`face plant'. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 10 Dialogue St yles

Dialo

gue styles: { manner in which info rmation is p resented and received.

The

most common a re: { T ext (emb edded systems, phones); { F

rms

(B2B systems, call centres); { Menus (desktop systems, some w eb interfaces); { Graphics (desktop, palmtops, the w eb).

Most

interfaces no w mix all

f

these st yles; { but p rop

rtions

va ry dep ending

n

users. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 11 T ext

F
nts:
describ

e the shap e

f

a cha racter;

serif

vs sans-serif.

Point

size:

determines

size

f

a cha racter;

1

p

int

is a 72nd

f

an inch.

It's

the RELA TIVE not the absolute size. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 12 F

rms
Mo

re advanced fo rms: { automatic pa rsing, context-sensitive.

Must

p rovide title

f

the fo rm. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 13 F

rms
Navigation:

{ tab to move b et w een elds; { ENTER to submit the fo rm.

Must

p rovide a cancel

ption.

CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 14 Menus

Many

dierent t yp es: { hiera rchical; pull do wn; tea r-o; p

p-up.
The

magic numb er is 7 +

r
2.

CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 15 Menus

Lo

w consequence

ptions

at the top.

Dynamic

menus recongured b y item frequency . CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 16 Graphics

Icons

help to p romote p ro duct identit y .

What

is the semantics

f

the image? CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 17 WYSIWYG

What

y

u

see is what y

u

get. nslideitemfWhat you see is not what you get.g

F

ew systems p rint exactly what y

u

see

n

the screen.

F
nts
n

the p rinter dier from those

n

screen.

Can

b e deeply frustrating... CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 18 Metapho r

Computers

rely

n

bina ry signals, p eople don't.

Provide

an abstract view

f

underlying complexit y .

Sho

w a desktop with folders and a trash-can.

Do

not sho w complex path info rmation: D:n >UsersnprofilesnJohns

n

CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 19 Direct Manipulation

Go
d

metapho rs:

supp
rt

skill transfer;

go
d

metapho rs reduce training requirements;

go
d

metapho rs encourage explo ration.

But

dir e ct manipulation systems must supp

rt:

{ rapid, incremental and reversible actions.

What

happ ens when the metapho r b reaks do wn? CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 20 Summa ry

Logical

and physical I/O devices.

Dialogue

st yles:

text;

fo rms; menus; graphics.

WYSIWYG,

Metapho r and Direct Manipulation.

Breakdo

wn. CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001

SLIDE 21 F urther Reading

Shneiderman
n:
interaction

devices pp305-343;

direct

manipulation pp 185-228.

Lots

mo re, read it fo r

p

en assessment! CS-1Q: HCI (Lecture 2) c

C.W.

Johnson, 2001