Interaction Jing Li CPSC 533C March 3, 2003

Overview Toolglass and Magic Lenses: The See- Through Interface (1993) by Eric A. Bier, Maureen C. Stone, Ken Pier, William Buxton, Tony D. DeRose by Eric A. Bier, Maureen C. Stone, Ken Pier, William Buxton, Tony D. DeRose SDM: Selective Dynamic Manipulation of Visualizations (1995) by Mei C. Chuah, Steven F. Roth, Joe Mattis, John Kolojejchick by Mei C. Chuah, Steven F. Roth, Joe Mattis, John Kolojejchick

Toolglass and Magic Lenses The see-through interface that can appear as though on a transparent sheet of glass between the application and the traditional cursor. These tools create spatial modes that can replace temporal modes in user interface systems.

Introduction Toolglass widgets: semi-transparent interactive tools that are used in an application work area, and appear on a virtual sheet of transparent glass called a Toolglass sheet. The user can line up a widget, a cursor and an application object in a single two-handed gesture. A widget that has been stretched across the entire work area creates a command mode. User can move sheet over application object or move the object to a widget (trackball can control both sheet and scrolling). Figure 1. Click-through buttons. (a) Six wedge objects. (b) Clicking through a green fill-color button. (c) Clicking through a cyan outline-color button

Introduction (Cont.) Many widgets can be placed on a single sheet Widgets and lenses can be composed to create a number of specialized tools from a basic set (e.g. an outline color palette over a magnifying lens, to point to individual edges) Figure 2. A sheet of widgets. Clockwise from upper left: color palette, shape palette, clipboard, grid, delete button, and buttons that navigate to additional widgets Figure 3. An outline color palette over a magnifying lens

Related Work Multi-Handed Interfaces Movable Tools –Menus that pop up at the cursor position –Toolglass sheets can be moved without tying up the cursor Transparent Tools –Make menus over the work area transparent Viewing Filters –Magic lenses are visual filters that may be used to change type of views or reveal hidden information.

Examples Shape and Property Palettes Figure 4. Shape palette. (a) Choosing a shape. (b) Placing the shape. Figure 5. Font face palette. The word "directly" is being selected and changed to bold face.

Examples (Cont.) Clipboards Figure 6. Symmetry clipboard. (a) Picking up an object. (b) Rotated copies appear. (c) The copies are moved and pasted. Figure 7. Fill-color rubbings. (a) Lifting a color. (b) Moving the clipboard. (c) Applying the color.

Examples (Cont.) Previewing Lenses Figure 8. An achromatic lens over a drop shadow lens over a knotwork. (Knotwork by Andrew Glassner)

Examples (Cont.) Selection Tools Figure 9. Vertex selection widget. (a) Shapes. (b) The widget is placed. (c) A selected vertex. Figure 10. The local scaling lens that shrinks each object around its own centroid (Tiling by Doug Wyatt)

Examples (Cont.) Grids Figure 11. Three grid tools

Examples (Cont.) Visualization Figure 12. Gaussian curvature pseudo-color lens with overlaid tool to read the numeric value of the curvature. (Original images courtesy of Steve Mann)

Implementation of Toolglass Sheets Multi-Device Input and Screen Refresh –Handles simultaneous input from two pointing devices and updates the screen after multiple simultaneous changes Filtering Input Through Lenses and Widgets –Modifies pointing events as they pass through widgets Filtering Output Through Lenses and Widgets –Modifies graphical output as it passes up through each widget

Implementation of Magic Lens Filters Recursive Ambush –catch the low level drawing calls typically a wrapper around the graphics context –and modify them, and then call the original graphics primitive e.g. modify “DrawLine” to set the color to “red” –works transparently across all applications –but complicated to make a new lens and debug

Model-In Model-Out –create new objects and transform them can be saved and used by any lenses over it –very powerful, but must allocate storage cross application is an issue Implementation of Magic Lens Filters (Cont.)

Reparameterize & clip –Modify global parameters to drawing –Redraw the model, but clipped to the boundary shape of the lens –Best example: scaling

Implementation of Magic Lens Filters (Cont.) Multiple model types need to be supported for cross-application functionality. Achieved by: –Type conversion: convert the model to be of the type required –Type tolerance: unchanged if does not understand a model

Toolglass & Magic Lens Conclusions See-through interface based on spatial modes Structured well for two-handed interaction May be integrated into any screen-based applications and tools

SDM: Selective Dynamic Manipulation of Visualizations Mei C. Chuah, Steven F. Roth, Joe Mattis, John Kolojejchick (Carnegie Mellon University) Mei C. Chuah, Steven F. Roth, Joe Mattis, John Kolojejchick (Carnegie Mellon University)

Motivation Need new interactive techniques for 2D and 3D visualizations. We want: –Selective: a high degree of user control –Dynamic: interactions all occur in real time, and interactive animation –Manipulation: Users can directly move and transform objects to perform different tasks This set of techniques is called SDM

Current Static Visualization Users cannot focus on specific object sets in detail while keeping them in the larger context Clutter and occlusion (hidden data) in dense information space Difficult to give a sense of scale: some objects may be dwarfed in the scale used for the entire data set (green objects in [Figure 1]) No tools provided to classify data sets and save those classifications Difficult to compare quantities when objects are not spatially contiguous (e.g. when objects are at different distances from the user)

SDM Sample SDM deals with these issues Selection and control methods rely on objects rather than spaces.

Sample: Supply Distribution Network Cylinders (red) : supply centres Rectangular bars (purple) : shelters Lines (black) on the floor plane : major routes Heights of cylinders and bars : quantities available at supply centres and needed by shelters Selected objects : green

SDM Components Object Centered Selection –Select objects by clicking or using sliders to place data constraints –Object sets may be named, saved and used later from a scrollable menu –Object sets need not be made up of homogeneous types (e.g. a set may contain supply centers, shelters, and routes)

SDM Components (Cont.) Dynamic and Flexible Operations –Directly manipulate through object handles –Attach a handle to an object, and push or pull on it: causes the object to expand, shrink or move continuously –Objects change with motion of handles (A) controls the radius of cylinder object (B) controls object height (C) controls bar width –Arrow handles: shift

SDM Components (Cont.) Object Constraints Context persistence –SDM maintains some relationship between the focus objects set and its environment. Set-wide operations –If you can move or scale one object in a focus set, you can move or scale any other object in this set.

SDM Feedback Mechanisms Clearly Identify the Selected Set –The selected set is painted differently (green) –A white grid may be drawn beneath all selected objects to indicate positions and spread Maintain Scene Context –Used to maintain context when objects are displaced –Object ‘body’ (green) and object ‘shell’ (white)

Feedback Mechanisms (Cont.) Maintain Temporal Continuity –Use animation to help users to perceive changes to the scene Maintain Relationships Between the Selected Set and the Environment –Keep a scale of the differences on screen, for example, the ratio axes technique (next slide) Allow Objects to be Easily Returned to Their Home Positions

Ratio Axes Technique Scale of the environment (black) & the selected set (red) The left is 1:1; the right is 1:8

SDM Solutions Focusing on a Select Set of Objects while Keeping Scene Context –Objects can be painted distinctly and the width can be increased –Users may shift all focus objects to the front of the scene

SDM Solutions (Cont.) Viewing and Analyzing Occluded Objects –Selected object set is elevated to solve occlusion problem

SDM Solutions (Cont.) –Reduce the heights of unconcerned objects to zero –Make all unconcerned objects very thin

SDM Solutions (Cont.) Viewing Different Sets of Elements Based on Different Scales –Ratio axes technique (mentioned above) Interactively Augmenting the Visualization with New Classification Infomation –Add width and color, save as a set and apply them later (i.e. identify important shelters)

SDM Solutions (Cont.) Comparing the Patterns, Widths, and Heights of Objects –Draw a line of reference in the scene plane and move any set of objects to the reference line –Compare data trends among multiple sets

SDM System Architecture

SDM Conclusions Good interactive techniques deals with the issues from current static visualizations Visualization is clear, precise and easy to understand The goal of SDM is to provide users with enough tools and flexibility (multiple alternative solutions) that they can solve a wide spectrum of data analysis tasks.