A method of drawing figures for a multi-window system in which a plurality of window regions are set on a display screen, and in which a window which is partly overlapped on other windows and is partly concealed is controlled by being divided into a plurality of display or non-display subregions, and the displayed content is changed by designating the window. If a dot constituting the figure is generated from a dot generator, coordinate values of the dot are compared with position data of the designated window to select a dot located in the window. The selected dot is compared with position data of a subregion that constitutes the designated window to find a particular subregion in which the dot exists. If the particular subregion is a display region, the dot located therein is produced on the display screen. A dot generated next is compared with the particular subregion and is determined to be displayed or not. When the dot lies outside the particular subregion, the region to be compared to the dot position data is changed, and the dot position is compared with another subregion or with the designated window.
An apparatus and method for displaying non-obscured pixels in a multiple-media motion video environment (dynamic image management) possessing overlaid windows. In an encoding process, only boundary values and identification values corresponding to each window on a screen are saved in memory of a hardware device. In a decoding process, the hardware device utilizes these initial boundary values saved in memory in such a way that when incoming video data enters the hardware device, the hardware device need only compare the incoming video data's identification with the identification saved in memory. The hardware device includes: compare logic devices, counters, minimal memory devices, a control logic block, and a driver.
An apparatus for moving graphical objects including a display for displaying multiple graphical objects according to a display priority, apparatus for moving, responsive to a user input, a displayed graphical object, and apparatus for modifying, responsive to a user input, a display priority of the moved graphical object as the graphical object is moved so that the moved graphical object is displayed under a portion of a second displayed graphical object. In addition, a method for moving graphical objects including displaying multiple graphical objects according to a display priority on a display, moving, responsive to a user input, a displayed graphical object, and modifying, responsive to a user input, a display priority of the moved graphical object as the graphical object is moved so that the moved graphical object is displayed under a portion of a second displayed graphical object.
An interactive computer graphics display system processing method for identifying a displayed primitive that intersects an operator selected area of the display screen. Pursuant to the method, the operator selected area of the display screen is reverse mapped to world coordinate space; data representative of displayed geometric primitives is then clipped against the reverse mapped selected area in world coordinate space; and clipped data representative of displayed geometric primitives that intersect the reverse mapped selected area are identified for operator defined application processing. Further processing steps include mapping of the identified data to screen coordinate space and rasterization of the data for display in the screen monitor. A zoom processing method is also provided wherein an original operator defined zoom window is transformed from screen coordinate space to world coordinate space and the boundaries of the transformed window in world coordinate space are utilized as data clipping boundaries. After clipping, data representative of a displayed geometric primitive outside the inverse mapped zoom window is discarded, thus preventing the rerasterization of geometric primitives outside the zoom window. Further processing includes mapping of the identified data to a defined zoom window in screen coordinate space for operator viewing and selection of a particular geometric primitive for application processing.
Methods and apparatus for capturing images on screens which display multiple windows. Exemplary embodiments eliminate unnecessary reading and writing of information pertaining to display data that is not visible. A user designates an arbitrary region of a screen to be captured, which can cross windows that are displayed at different layers within the image. A snapshot of the selected region is obtained by retrieving data for each of the pixels in the region, converting them into standard values, and storing them in an off-screen pixel map. Before the data for the pixels is obtained, a listing is made of all windows that are encompassed by the designated region. For each window a record is made of the portion of the window that is visible within the designated region. If no portion is visible, the window is removed from the list. After all of the windows within the region have been examined in this manner, only the pixels pertaining to the recorded visible portion of each window need to be read and stored in the pixel map. With this approach, redundancy is eliminated, since only the visible pixel data is retrieved and written to the pixel map.
A method and apparatus can set validity of the operation for a piece of information to be displayed on a display terminal, such as a displaying, scaling or underwriting operation, and to allow the operation of the displayed information responsive to the information indicating the validity. In the operation of a multi-window controlled screen, a desired screen can be easily displayed closest to the user. Moreover, the information displayed on a screen is divided into a constant unit, and the information indicating validity of the operation is caused to correspond to the divided unit. This information is separately displayed to the user as an icon. Then the overwriting, deleting, moving or scale changing operation, or the like, can be accomplished independently of one another so that a desired document can be easily made. If the invention is applied to an electronic mail system, the document can be easily overwritten.
