GB2261095A

GB2261095A - Interactive display system

Info

Publication number: GB2261095A
Application number: GB9123270A
Authority: GB
Inventors: David Wynne Williams; David Watson
Original assignee: International Business Machines Corp
Current assignee: International Business Machines Corp
Priority date: 1991-11-02
Filing date: 1991-11-02
Publication date: 1993-05-05
Also published as: GB9123270D0; JPH05224856A

Abstract

The interactive display system is of a type in which a user can smoothly change using a user input device, such as a valuator or dial 30, the value of a parameter of a displayed image 50 within a range having predetermined logical limits for the parameter, the user input device providing no physical limits, corresponding to the logical limits, for the change, the system being characterised by means for providing an audible indication, to the user when the parameter reaches one of the logical limits. In an embodiment of the invention the system continues to give said audible indication to the user after the parameter has reached said one of the logical limits and during continued attempts by the user to change the parameter beyond the reached limit. <IMAGE>

Description

INTERACTIVE DISPLAY SYSTEM The invention relates to display systems and, more particularly, to interactive display systems of the type having user input devices, such as valuators or dials, which can be used interactively to change parameters of a displayed image and for which logical limits must be set, but which provide no corresponding physical limits for the available parameter range.

Many graphics workstations have programmable hardware user input devices known as valuators or dials. These may be used by applications to perform any task requiring users to change smoothly a parameter over a given range. The parameters might be, for example, the translation, scaling or rotation of a two or three-dimensional image or, in more sophisticated systems, the colour or texture of the surfaces of displayed objects or even a parameter In an equation governing the form of a displayed object. These type of devices often have the characteristic of having no physical Limits for the input supplied to the workstation. For example, in the case of rotary devices, they are often capable of an infinite number of turns.This has the advantage that the devices can be programmed to be extremely sensitive and yet still change a parameter over a wide range of values. Nevertheless, in most cases, a logical limit for the parameter being controlled by the device must be set by the software controlling the device.

One problem with this type of system is that a user is often unaware that the value of a parameter has reached a limit of the range within which it can be changed. The problem can be particularly acute in modern high-resolution graphical display systems where parameters can be changed over a wide range and changes to the parameter may only produce very subtle changes to thedisplayed image which are not immediately apparent to the user.For example, in the case where a parameter of an equation governing the form of a displayed object is being controlled, it is not clear to t. user whether the parameter is in a region of parameter space where dianges.to it have no effect on the image or whether in fact a logical limit has been reached The usual approach to this problem has been to provide the user with visual feedback, on the display screen, of the position of the valuator or dial devices using an image of a slider or a dial, which has the limits marked on it, or even by providing the user with a numerical value for the parameter.The user can then examine these and compare the current value with the limits. However this has the disadvantage that the user must continually look at the position of the dial or slider and this can distract them from the interactive work they are performing on the displayed image. In addition, this approach inevitably requires space on the display surface, reducing the space available for, or covering up part of, the image itself.

According to one aspect of the present invention, there is provided an interactive display system of a type in which a user can smoothly change, using a user input device, the value of a parameter of a displayed image within a range having a predetermined logical limit for the parameter, the user input device providing no physical limit, corresponding to the logical limit, for tiie change, the system being characterised by means for providing nn audible indication to the user when the parameter reaches the logical 1 imit.

In a preferred form of the invention the system continues to give said audible indication to the user aFter the parameter has reached said logical limit and during continued attempts by the user to change the parameter beyond the reached limit.

The audible indication ensures that, even if the user cannot immediately tell from the image that continued actuation of the input device is not producing a change in tlie image because one of the limits has been reached, they are immediately made aware of the fact without their concentration on the work in hand 1)c'iflg broken. The invention therefore allows the usability of the display system to be significantly improved.

The user input device can, for example, be a rotary dial or a mouse device on which a button is held depressed whilst a screen pointer is located in a particular region of the screen to produce the change in the parameter. The audible indication can be a continuous tone or a single pulse.

Viewed from another aspect the invention provides a method of operating an interactive display system of a type in which a user can smoothly change, using a user input device, tlie value of a parameter of a displayed image within a range having a predetermined logical limit for the parameter, the user input device providing no corresponding physical limit for the change, the method comprising providing an audible indication to the user when tiie parameter reaches the logical limit. The method can include continuing to provide said audible indication to the user after the parameter has reached said one of the logical limits and during continued attempts by the user to change the parameter beyond the reached limit.

An embodiment of the invention will now be described, by way of example only, with reference to the. accompanyilig drawing wherein: Figure 1 is a diagram showing an interactive display system in accordance with the present invention; Figure 2 is a flow diagram showing the procedure used by the interactive display system.

Referring to Figure 1 there is showti aii interactive display system comprising display device 10, system ititit 20, set of dials 30 and keyboard 40. Triangular object 50 is displayed on the display screen.

A user can smoothly change the orientatioll of object 50 as it is displayed on the screen using one of the dials 30. This is illustrated by the arrows on Figure 1. As will he clear to a man skilled in the art, any digital system will in fact only change the image in discrete steps However the word "smoothly should be understood to apply to the users' perception of the changes to the image.

The display system periodically reads the setting of the dial 30 and, if the setting has changed since the last time the dial was read, it is programmed to update the image on the screen accordingly.

Each time the dial is read, its setting is compared with logical limits, such as +/- 360 degrees, stored in the display system for the orientation of the object. If the setting is equal to or lies beyond either one of these limits, then the keyboard alarm is sounded by the system unit 20 alerting the user that further rotation of the dial will produce no further change in the image of the object displayed on the screen.

It the setting on the dial c-ontitmes to change in the same direction, the alarm is sounded repeatedly until the change ceases.

Figure 2 is a flow diagram ilAllstrnling the procedure performed by the system.

In this embodiment of the invention tlle display of the object and the changing of the parameter are carried out using an appropriate computer program running on a interactive graphics workstation. However it should be noted that the invention collltl be implemented in hardware, for example as a hardware feature of slWh a workstation, or indeed could be implemented as any combination of hardware and software. The invention could also be implemented as part of a graphics software package designed to interface applications programs to such a workstation.

Claims

1. Interactive display system of a type in which a user can smoothly change, using a user input device, the value of a parameter of a displayed image within a range having a predetermined logical limit for the parameter, the user input device providing no physical limit, corresponding to the logical limit, for the change, the system being characterised by means for providing an audible indication to the user when the parameter reaches the logical limit.

2. Interactive display system as claimed in Claim 1 wherein the system continues to give said audible indication to the user after the parameter has reached said logical limit and during continued attempts by the user to change the parameter beyond the reached limit.

3. Interactive display system as claimed in Claim 1 or Claim 2 wherein the user input device is a rotary dial capable of an infinite number of turns.

4. Interactive display system as claimed in any preceding claim in the form of a graphics workstation having a pltirality of said user input devices.

5. Method of operating an interactive display system of a type in which a user can smoothly change, using a user input device, the value of a parameter of a displayed image within a range having a predetermined logical limit for the parameter, the user input device providing no physical limit, corresponding to the logical limit, for the change, the method comprising providing an audible indication to the user when the parameter reaches the logical. limit.

6. Method as claimed in claim 5 inclllding continuing to provide said audible indication to the user after theparameter has reached said logical limit and during continued attempts by the user to change the parameter beyond the reached limit.