In this computer graphics display system, individual viewports of arbitary arrangement, number and content are produced on a video screen. The graphics content, display parameters and interviewport spacing all are specified by a set of control word sequences stored in a control table. Each sequence is associated with one scan line segment of an individual viewport, and consists of one or more control words that specify (a) the graphics image memory location of the pixel data to be included in that viewport segment, and (b) display parameters which specify how that pixel data is to be processed before supply to the video screen. Control word display parameters and the associated graphics image (pixel) data are alternately obtained from a control/pixel memory and supplied to a first-in-first-out (FIFO) memory. At the outbound side of the FIFO memory, a controller enters the display parameters in appropriate registers. Pixel data then is serialized and processed in accordance with these display parameters, which may include color, zoom replication, and background grid insertion. After supplying the processed graphics data to the video screen, the controller supplies background control signals so as to produce an interviewport region on the video screen in accordance with the interviewport spacing specified by the control word sequences. Panning in any viewport is accomplished by altering the control word sequences associated with successive video frames so as to specify different sets of pixel data which, when reproduced in successive frames, give the illusion of image movement.
A method and computer program are provided for controlling access to a memory device wherein, even with a complex data storage structure, access is made to memory areas within the memory device with a minimal number of selection inputs required for selection of a desired memory area.
A display unit includes a display area for displaying first and second data groups, a control circuit for dividing the display area into at least two portions when the first data group is displayed in the display area, a circuit for controlling a cursor to be displayed in the display area, a circuit for identifying a display portion that contains the cursaor, a circuit for selecting a particular portion that does not contain the cursor, according to the output from the identifying circuit, and a circuit for controlling the second data group to be displayed in the particular portion selected by the selecting circuit.
A multi-window display station having main frame (host) interactive and local personal computer display data buffers is provided. The outputs of the two data buffers are merged, using a row or swath buffer, according to default or escape codes stored in one of the data buffers and the combined output drives a plasma panel display. Registers for modified data tags and for presence/absence of escape codes speed the panel update process. Means are included to provide alpha-numeric and graphic windows together on the panel screen.
In a document processing method using a multiwindow including a display device having a display screen on which a plurality of windows are established, a virtual screen memory in which a plurality of virtual screens each corresponding to programs are generated to output results of data processing by programs, a memory unit for storing therein a window control table defining corresponding relationships between the virtual screens and the windows, and a control device for referencing the window control table and for outputting contents of each virtual screen in a window associated with the virtual screen on the display screen, copy source attribute data including an identifier of a second window established in the display screen and data defining a second partial region in the second window is memorized in correspondence with a first partial region on the vertical screen so that, in response to a command inputted by an operator while painting to the first partial region displayed in the first window, the display contents of the second partial region of the second window are copied into the first partial region of the first window based on the copy source attribute data stored on the virtual screen corresponding to the first window.
An information display system includes a raster-scan display screen DS and an information store IS for storing information to be displayed on the screen. The store has a capacity greater than the maximum amount of information which may be displayed at any one time. Display controller DC is operable to generate a succession of screen addresses of successive areas of the display screen DS, and mapping memory MU is provided to translate each screen address into a store address indicating the location in the information store IS of the information to be displayed in that area of the display screen. Display logic DL is provided to produce from the store output the necessary signals for activating the display. Map changes MC are provided to enable the translations effected by the mapping memory MU to be varied as required to change the display. One or more input devices ID allow information to be written into the display store.
