CHAPTER 6 BEN CARSON SUNIL D SOUZA RAJESH GOLLA

Section Introduction Users of systems incorporating direct manipulation are enthusiastic supporters Traits of direct manipulation systems typically include: Easy to learn Competent and efficient use of the system Enjoy using Eager to learn more about the system Visibility of objects and actions

6.2 – Examples Word Processing Systems Spreadsheets Spatial data management Video games Computer Aided Design Office Automation

Word Processing Progression of word processing systems Line-oriented Full-page display editors WYSIWYG Enhancements Inclusion of objects Desktop publishing Slide presentation software Hypermedia environments Improved macros Spell/grammar checkers and thesauri Documents assemblers Enjoyment from easily designing complex documents versus original command line editors

Spreadsheets Progression of spreadsheets VisiCalc Lotus Excel Enhancements Graphics 3-D representations Multiple sheets Database features Enjoyment from ease of making many tedious calculations quickly and representing it in many meaningful forms

Spatial Data Management Visual representation of a specific area of interest Personnel of a company Map with travel information File directories Enjoyment from interacting with the visual elements of this type of system

Video Games PONG 1 st video game Commands are physical actions, results on- screen Can be entertaining and/or educational Differs from other systems behavior Game systems challenge the user Non-game systems try not to challenge the user Enjoyment from user being challenged and entertained

Computer Aided Design (CAD) “virtually” design products and receive quick feedback Computer aided manufacturing Aids in improving already existing processes Enjoyment from ability to manipulate systems directly and easily view multiple alternatives.

Office Automation Uses direct manipulation principles hardware and software has evolved to support more and better graphics, dropdowns, icons, etc. Enjoyment from easier working environment than with command line based environments

6.3 - Explanations of Direct Manipulation Nelson Principle of virtuality Rutkowski Principle of transparency Hutches Gulf of execution and evaluation All refer to making the interface as invisible as possible

Problems with Direct Manipulation Visual representation may not be the best way to represent a particular problem or scenario Must learn meaning of visuals Can be misleading Using a mouse can be more time- consuming than a keyboard

Objects-Actions Interface (OAI) model explanation of direct manipulation D.M. systems usually have the following Consistent and meaningful visual representations and actions Physical actions or labeled button presses replace complex command syntax Quick reversible changes on objects with immediately visible results Users report D.M. systems to be Easy to learn Experts are very fast and effective and can expand upon existing functionality of the system Easy to retain knowledge Error messages rarely needed Less anxiety-inducing because of ease-of-use and reversible actions D.M. systems operate on a high-level task domain Easy of learning and use is a result of their more intuitive interface, compared with command syntax based environments

6.4 Visual Thinking and Icons Concepts of Visual language and visual thinking- promoted by Arnheim (1972) Computer provides remarkable visual environment New- WIMP Old -inflexible and stubborn Different people have different cognitive styles

Issue of Icons An icon is an image, picture or symbol representing a concept. For visually oriented tasks- stay visual by using icons For text document- stay textual by using textual menus Sometimes use a “mix” of both.

ICONS or TEXT Icons or Text – depends on  Users  Tasks  Quality of the icons or tasks.

Icon specific guidelines 1.Represent the object in a familiar manner. 2.Limit he number of icons. 3.Make the icon stand out from its background. 4.Consider 3-D icons. 5.Single selected icon clearly visible when surrounded by unselected icons. 6.Make each icon distinctive from every other icon. 7.Ensure the harmoniousness of each icon as a member of family of icons. 8.Design the movement animation. 9.Add detailed information. Ex-shading to show size of file. 10.Explore the use of combinations of icons.

Four levels of design 1. Lexical qualities: Machine generated tasks-pixel shape, color, brightness, blinking. 2. Syntactics: Appearance and movement-lines, patterns, size, shape. 3. Semantics: Objects represented- concrete versus abstract, part versus whole. 4. Pragmatics: overall legibility, utility, identifiable, memorable, pleasing. 5. Dynamics: receptivity to clicks.

6.5 Direct Manipulation Performing tasks by DM- not the only goal Programming by DM

CHALLENGES Five challenges of programming in the user interface 1. Access to appropriate date structures. 2. Sufficient computational generality. 3. Ease in programming and editing programs. 4. Simplicity in invocation and assignment of arguments. 5. Low risk.

6.6 Home Automation. Prediction of larger market in extensive controls in homes- but only if the user interfaces can be made simple.

6.7 Remote Direct Manipulation Teleoperation/Remote Controlled Environment E.g.: Home-automation, applications underwater

TELEMEDICINE Disadvantages Time Delays Incomplete Feedback Cumbersome due to multiple sensors Unanticipated Interferences

6.8 VIRTUAL ENVIRONMENTS Components Visual display Head position sensing Hand position sensing Force feedback Sound input and output

6.9 SUMMARY  More resources, possibly  Some actions cumbersome  Tracing difficult?  Difficult for visually impaired users BenefitsConcerns  Faster feedback  Reduced error rates  Faster learning & retention  Encourages innovation

6.10 RESEARCHERS AGENDA  Better understanding of factors  Better history keeping  Encourage innovation in DM using software tools