Interactive display system and method for menu selection

Abstract: The present invention provides an interactive display system, and method of operating such a system, in which a vertically extending menu bar is displayed at the right or left end of a screen. A pull-down menu is further displayed which downwardly extends in an arc from a selected item of the menu bar towards the centre of the screen. The character string display of each menu bar item is inclined and space is omitted. The locus along which the pull-down menu extends can be calibrated by the user.

Description: The present invention is related to an interactive display system and method, and in particular to user interfaces of such display systems which provide a selection menu in the display screen of a display device or the like. The conventional computer user interaction technique has been developed mainly on the basis of a bit map display and mouse (or tablet), and is designed for user operation on the assumption that the whole screen is basically visible. A typical example of user interaction is the use of a menu. This is a technique in which choices such as commands are displayed on a bit map display and selection is by the use of a pointing device such as a mouse. Typically a pull-down menu is provided as shown in Figure 1 in which the menu is hierarchical to improve usability. In this menu system, a menu bar is usually positioned in the upper portion of a display or window, the individual items being laterally arranged, and a pull-down menu is vertically displayed. Since a user generally scans the screen from top to bottom in a system using a mouse and a bit map display, such an arrangement between the menu bar and the pull-down menu is very efficient. Nowadays, due to the advances made in sensor and liquid crystal technologies, integrated I/O devices using transparent tablets and liquid crystal displays have become more common, and are tending to replace the bit map display and mouse. Such devices are characterised in that an item on display can be directly operated (the position of the item being displayed is coincident with that of the object to be operated). However, the direct use of the conventional pull-down menu system has the following problems. (1) The menu items on the menu bar at the side of the arm holding a pen are hidden. (See Figure 2.) (2) The pull-down items are also hidden by the hand while they are being selected in the downward direction, even though the first item is in sight. (See Figure 3.) Published Unexamined Japanese Patent Application Nos. 254233/1987 and 205722/1988 relate to techniques for improving the conventional menu bar and pull-down menu scheme. The menu bar is laterally arranged at the top of the screen as in the conventional menu bar. A method for diagonally displaying a pull-down menu is disclosed in IBM Technical Disclosure Bulletin Vol.32, No.8, pp.370-372, Jan. 1990, but the menu bar is also laterally arranged at the top of the screen in this method. Further, it is known to provide a user interface in which icons representing applications may be vertically lined up, for instance, at the right end of the screen (IBM AIX NextStep Environment/6000, sc23-2357, p.2-29), but this is to display frequently used applications in order to aid understanding, and thus pen input is not taken into consideration. Further, with such an interface, an application is merely initiated by selection of an icon, and a pull-down menu or the like is not displayed. Hitherto display systems have not provided flexibility in the positioning of data to provide easy readability, particularly when the user is using a hand-held printing device. The object of the present invention is to provide an interactive display system, and method of operating such a system, which provides such flexibility. Accordingly, the present invention provides a menu display system comprising: means for displaying a set of menu items on a display screen in a vertical direction; means for sensing a plurality of points input by a pointing device along a diagonal direction; means, responsive to the selection of one of the set of menu items, for displaying a pull-down menu along a path defined with reference to the inputted points. Viewed from a second aspect the present invention provides a method for displaying a menu and pull-down menu on a display screen comprising the steps of: displaying a set of menu items on a display screen in a vertical direction; fitting a plurality of points input by a pointing device to an arc; and responsive to the selection of one of the menu items, displaying a pull-down menu aligned along the arc projecting diagonally from the selected menu item. In the present invention, a menu bar is vertically lined up at the right or left end of a screen (or window), preferably, at the user's dominant arm side, whereas the conventional menu bar is laterally lined up at the top of a screen (or window). Preferably, the pull-down portion is displayed in an arc shape in consideration of the movement of the wrist. (See Figure 4.) Hereinafter, the description given is for right-handed users using a display screen in its conventional vertical orientation - "left" and "right" are to be reversed for left-handed users. The pull-down angle is calibrated before use since it depends on factors such as left- or right-handedness, the size of the hand, the length of the upper arm, and the work space position (particularly, the angle from the center of the chair back). In addition, in order to prevent space from being wasted in continuity of the operation from the menu bar and left-to-right writing of characters, the content of the menu bar items may be displayed at an angle (the contents of the menu bar may be represented by icons). When a user points at the screen with a pen, the arm is placed from the lower right to the upper left of the screen. With the conventional menu bar laterally arranged at the top of the screen or window, when a certain item is selected, the adjacent item is hidden by the hand as shown in Figure 3. The present invention has the advantage that all the items are displayed without being hidden. Further, with the conventional vertically arranged pull-down menu, the arm is moved to a great extent or the wrist is forced to move unnaturally when a lower item is to be selected; thus for such applications the conventional menu bar does not provide good operating properties. However, with the system of the present invention, all the menu items can be selected by a motion which does not impose any unnatural force on the wrist of the user. The present invention will be described further, by way of example only, with reference to an embodiment thereof as illustrated in the accompanying drawings, in which: Figure 1 illustrates the conventional pull-down menu system; Figure 2 further illustrates the conventional pull-down menu system; Figure 3 shows the conventional pull-down menu system; Figures 4 to 6 are illustrations to outline the preferred embodiment of the present invention; Figures 7 and 8 illustrate the calibration technique of the preferred embodiment of the present invention; Figure 9 illustrates the offset calculation employed in a conventional vertically arranged menu; Figure 10 illustrates how an offset value is calculated for fitting the menu to an arc; Figure 11 illustrates the system configuration of the preferred embodiment of the present invention; Figure 12 is a diagram showing the main portions of the system of the preferred embodiment; Figure 13 is a diagram showing the menu processing part of the system of the preferred embodiment in further detail; Figure 14 is a flowchart for illustrating the operation of the calibration process of the preferred embodiment; Figure 15 is a flowchart illustrating calculation of position and slant values in accordance with the preferred embodiment of the present invention; Figure 16 is a flowchart illustrating the menu processing steps in accordance with the preferred embodiment of the present invention; and Figure 17 is a flowchart illustrating how the pull-down item displaying position is determined in the system of the preferred embodiment. Since the locus for tracing the pull-down menu with a pen without causing an unnatural force depends on the individual, calibration for each individual is desirable. First, each individual is caused to indicate one point on the screen as shown in Figure 7. Then, the wrist is caused to indicate an end point to which it can move without causing unnatural force, and the locus traced by the pen point is fitted to an arc, thereby obtaining an arc along which the menu is to be displayed. Menu Bar Subsystem This can readily be created by exchanging the X- and Y- coordinates of the offset calculation in the current menu bar subsystem. However, since it is considered that each item length of the menu bar (usually, one to two words) is short enough in comparison to the radius of gyration of the wrist, the inclination angle is to be constant. Pull-down Menu Subsystem In the conventional vertically arranged menu system, a vertical offset is merely added to the end when the next item is created after the first item has been created. (See Figure 9.) However, in the menu system of the preferred embodiment of the present invention, the position of the subsequent item is determined by the method shown in Figure 10 on the basis of the calibration data shown in Figure 8. This method can readily be added to the existing menu system. The above-mentioned calibration function and the modifications to the menu bar subsystem and pull-down menu subsystem will now be described in more detail. Figure 11 shows the system configuration of the preferred embodiment, in which the system comprises personal computer 1, operating system 2 and user interface management system 3. Personal computer 1 is, for instance, a PS/55 of IBM Japan, Ltd. (PS/55 is a trademark of International Business Machines Corporation, U.S.A.), and consists of processor 4, liquid crystal display device 5, transparent tablet 6a and pen 6b. Operating system 2 is, for instance, AIX PS/2 of IBM Japan, Ltd. (AIX and PS/2 are trademarks of International Business Machines Corporation, U.S.A.). This operating system 2 includes window system 7 which manages the output to liquid crystal display device 5 and the input from transparent tablet 6a. User interface management system 3 performs complex processing of the inputs and outputs such as the menu processing, and in this system, executes data reception and transfer to the display/selection/application programs of the menu. Figure 12 illustrates data reception and transfer between user interface management system 3 and window system 7 of Figure 11. In Figure 12, user interface management system 3 has event handler 10 as well as window manager 8 and menu processing system 9. Event handler 10 receives event information from window system 7 and passes it to window manager 8 and menu processing system 9. Window manager 8 modifies the position or size of the window according to the event information. Menu processing system 9 is adapted to execute the process routines, shown in Figures 14 to 17 and described later, according to the event information, and includes a menu bar information management section 11, pull-down information management section 12 and calibration information management section 13. These information management sections 11, 12 and 13 will be described later. With such a configuration, a user performs a calibration ahead of time and the application program logs the menu data. Thereafter, when the user gives an indication using pen 6b on transparent tablet 6a, window system 7 on operating system 2 generates event information in response to the user indication and sends it out to user interface management system 3. User interface management system 3 provides instructions for performing the display and selection of the menu to menu processing system 9 according to the event information, and menu processing system 9 displays the menu on liquid crystal display device 5 via window system 7 for item selection from the subsequent event. When the menu selection is determined, the previously displayed menu is erased and the selected data is transferred to the application program. Figure 13 further depicts the configuration of menu processing system 9 of Figure 12. In Figure 13, menu processing system 9 has a menu bar information management section 11, pull-down information management section 12 and calibration information management section 13. Menu bar information management section 11 includes the display information (display character string, color, font, display icon data, size (width, height), etc.) of all the items constituting the menu bar, position information (coordinates of the position of the start point for displaying each item), inclination angle, and an index pointing to pull-down information. Pull-down information management section 12 includes the display information (display character string, color, font, size (width, height), etc.) of all the items constituting the pull-down menu, and application data to be passed to the application program when actually selected. Calibration information management section 13 includes the information of the arc based on the swing of the user's wrist (central coordinates of the relative arc as seen from the position at which the pen point is positioned). The operation of the preferred embodiment is now described. To explain the utilization of the menu system, three stages are sequentially described, namely: (1) calibration process, (2) initialization by the application program, and (3) interactive menu. The switching of these three processes is usually performed by operating system 2 or another independent application software. (1) Calibration Process The calibration process is used to extract the information on the elements of the swing of the user's wrist and to process it into a form which can be treated by the previously described calibration information management section 13. The calibration procedure will be described further with reference to Figure 14. The user first informs the system that he will perform a calibration (execute the calibration software). The system then provides a window for calibration to the user and waits for input (step S1). When window system 7 notes that the user has dropped the point of pen 6b within the window (transparent tablet 6a has sensed the coordinates and simultaneously confirmed that the pen point has been contacted with it), the sampling of data for calibration is initiated (step S2). If the user moves the pen point even slightly, window system 7 sends the data of the pen point to menu processing system 9. Although menu processing system 9 provides echo display to the user, it does not recognize the inputting of a new point until the pen point of the user moves a fixed distance, and only if the movement is equal to or exceeds that distance does it recognise the pen point as a new point and store the coordinates of the point in the system (step S3). The sampling is repeated until the pen point is disengaged from transparent tablet 6a (step S4). As a result, point string data of the movement of the pen point of the user is obtained. Then, using both end points and the middle point of the obtained data string, the point string is fitted to an arc. The fitting method is as shown in Figure 8. The arc data (Cx, Cy, Cr) obtained from this is discriminately displayed in superposition on the previously echoed back and displayed locus of the pen point of the user (for instance, overwritten with a different color) (step S5). If the user is dissatisfied with the fitting, the calibration steps can be repeated (step S6). By transferring the data (Cx-X0, Cy-Y0) of the finally obtained arc data to calibration management section 13, the calibration process is terminated (step S7); (X0, Y0) represents the coordinate value of the first point of the pen point data. Since the difference between right-handedness and left-handedness appears in the sign of Cx (Cx>=0 for right-handedness, Cx<0 for left-handedness), no special branch processing is required. (2) Initialisation by the Application Program This initialisation is performed in a manner similar to the conventional menu system, for instance, AIX Windows or OS/2 Presentation Manager of IBM Japan, Ltd. Firstly, the application program performs the setting of the display information (display character string, color, font, display icon data, etc.) of all the items constituting the menu bar of menu bar information management section 11, the display information (display character string, color, font, size (width, height), etc.) of all the items constituting the pull-down part of pull-down information management section 12, and the application data provided to the application program when actually selected. Then, the size (width, height) is obtained and set using the character string length and font information from the display information of each item of menu bar information management section 11 (for instance, if AIX PS/2 of IBM Japan, Ltd. is used as operating system 2 and AIX windows of the said company is used as window system 7, the system can be allowed to perform the calculation using that information). Furthermore, from such information, the position information (the coordinates of the position of the start point for displaying each item) and the inclination angle is calculated by the procedure shown in Figure 15. First, the region available for the menu bar (MBWidth, MBHeight) is calculated from the window size required by the application, the size of the currently available screen, and the window size required by the user (step S11). Next, only for those items having display information in characters, the maximum value of their width (WidthMax) is calculated. The maximum value of the height (HeightMax) is similarly calculated (step S12). If this value (WidthMax) is smaller than the previously stated MBWidth, the default inclination angle is set; otherwise  is calculated from MBWidth = HeightMax*sin() + WidthMax*cos() This value is then compared with the maximum inclination value previously possessed by the system and the smaller one is set as the inclination angle (step S14). Next the positions of the items are sequentially determined using this inclination value. First, the position (Y-coordinate) of the first item is calculated from the following equation. y = HeightMax*cos() + WidthMax*sin() Then, the subsequent items including the second item are determined by sequentially adding dy = HeightMax*cos() to the preceding Y-coordinate (steps S16, S17). As the X-coordinate, a fixed value x = HeightMax*sin() is set throughout all the items (steps S16, S17). Finally, the initialization by the application program is terminated by setting the index of pull-down information management section 12 pointed to from each menu bar item in the index within menu bar information management section 11. (3) Interactive Menu Processing The menu processing flow is shown in Figure 16. Menu processing system 9 first uses the data of menu bar information management section 11 to display the menu bar in the window specified by the application (step S21). Since all information required to display each item has already been set at the time of the previous initialization, no special calculation or the like is required at this point. For display of a character string, all that is needed is that the point at the lower left of a string box just surrounding the character string represent the coordinates of position information for each item and display is made with inclination of the angle specified by the inclination angle. Icons or the like may be displayed without inclination. When an event is sent from window system 7 to indicate that the user has clicked the pen point on some item, then the coordinates of the pen point are used to determine which item has been pointed to and the process then moves to the pull-down processing (step S22). The pull-down processing also begins at the pull-down menu display. Firstly, using the index of pull-down information management section 12 corresponding to the selected item of the menu bar, pull-down management information is obtained (step S23). Then, using this information, the calibration information and the coordinate values of the selected pull-down item, the pull-down item is displayed (step S24). The method for determining the display positions of the pull-down items is described later in Figure 17. Then similarly to the above menu bar case, it is determined from the event of the pen point coordinates which item has been selected (step S25), and the application data corresponding to the particular item is delivered to the application program (step S26). Finally, the menu processing is terminated by erasing the pull-down items from the screen (step S27). In addition, if a menu selection event occurs outside the pull-down items display area, it is deemed that the menu processing has been cancelled. The above described method for determining each pull-down item displaying position is now described further with reference to Figure 17. Firstly, the coordinates (Xs, Ys) of a point at the upper right of a string box surrounding the character string of the first item are determined as follows (step S31): Xs = X-coordinate value of the left end of menu bar region Ys = Y-coordinate value of selected pull-down item Then the following values are preliminarily calculated for the subsequent calculations (step S32): Px = Xs + (Cx - X0) Py = Ys + (Cy - Y0) Where (Cx - X0) and (Cy - Y0) are the previously described calibration data. For the second item or an item thereafter (i + 1-th item), the coordinates are recurrently calculated using the preceding coordinate values (Xi, Yi) and (Px, Py) in the following manner (step S33): Xi + 1 = Xi - (Px - Xi)/(Py - Yi)*(Height of display of i-th item) Yi + 1 = Yi + (Height of display of i-th item) By sequentially calculating this for all the remaining items, all the display positions can be determined. Various modifications to the preferred embodiment are possible. For instance, if the pen is provided with a button, the pen button can be used to trigger a selection, or to specify selection or cancellation. Moreover, a vertical menu bar may be displayed as needed, or the vertical menu bar and the conventional lateral menu bar may selectively be displayed. In addition, it is also possible to display the vertical menu bar in the standard system using a bit map display and a mouse. Furthermore, it will be apparent to one skilled in the art that the present invention can also apply not only to personal computers but also to interactive systems such as workstations and remote terminals. As described above, in accordance with a preferred embodiment of the present invention, the inconvenience of the menu bar being hidden by the user's hand can be avoided even when selection is performed by directly contacting the tablet surface with a pen. It has been found that an embodiment of the present invention can be constructed by newly adding a calibration function to the conventional menu system and also by modifying the menu bar subsystem and pull-down subsystem.

Claims: A menu display system comprising: means (9) for displaying a set of menu items on a display screen in a vertical direction; means (7) for sensing a plurality of points input by a pointing device along a diagonal direction; means, responsive to the selection of one of the set of menu items, for displaying a pull-down menu along a path defined with reference to the inputted points. A system as claimed in claim 1 wherein the set of menu items is displayed along a vertical edge of the display screen. A system as claimed in claim 1 wherein the set of menu items is displayed along a vertical edge of a window of the display screen. A system as claimed in any preceding claim further comprising calibrating means for fitting the points input by the pointing means to an arc, the pull down menu being aligned along the arc extending from the selected menu item. A system as claimed in claim 4 wherein the calibration means comprises: a detector for sensing the coordinates of a path on the screen entered by a user with the pointing device; and fitting means for mathematically fitting the path to an arc. A system as claimed in any preceding claim further comprising means for selecting which edge of the display screen or window to display the set of menu items. A method for displaying a menu and pull-down menu on a display screen comprising the steps of: displaying a set of menu items on a display screen in a vertical direction; fitting a plurality of points input by a pointing device to an arc; and responsive to the selection of one of the menu items, displaying a pull-down menu aligned along the arc projecting diagonally from the selected menu item. A method as claimed in claim 7 wherein the step of fitting a plurality of inputted points comprises the steps of; sensing (S2, S3) the coordinates of a path on a touch-sensitive display screen entered by the users with the pointing device; and mathematically fitting (S5) the path to an arc. A method as claimed in claim 8, further comprising the step of: displaying (S5), on the display screen, the arc created by the fitting step for the approval of the user.

Inventors: ONO MAKOTO, ONO, MAKOTO
Applicants: IBM, INTERNATIONAL BUSINESS MACHINES CORPORATION
Application year: 1993
Main classification: G06F3
IPC codes: G06F3