Graphic display control system

• US 5,610,630 A
• Filed: 01/11/1996
• Issued: 03/11/1997
• Est. Priority Date: 11/28/1991
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Nakamura, Hiroshi, Nishikawa, Katsuhiko
• Primary Examiner(s): Hjerpe, Richard
• Assistant Examiner(s): LAO, LUNYI
• Application Number:
  US08/584,156
• Time in Patent Office: 425 Days
• Field of Search: 345/1, 345/2, 345/3, 345/119, 345/120, 345/200, 345/201, 345/189, 345/190, 345/132, 345/157, 345/156, 345/133, 395/157, 395/164
• US Class Current: 715/788
• CPC Class Codes: G06F 3/14 Digital output to display device ; Cooperation and interconnection of the display device with other functional units
• CPC Class Codes: G06F 3/1423 controlling a plurality of local displays, e.g. CRT and flat panel display
• CPC Class Codes: G09G 2340/12 Overlay of images, i.e. displayed pixel being the result of switching between the corresponding input pixels
• CPC Class Codes: G09G 2340/125 wherein one of the images is motion video
• CPC Class Codes: G09G 2360/126 The frame memory having additional data ports, not inclusive of standard details of the output serial port of a VRAM
• CPC Class Codes: G09G 3/003 to produce spatial visual effects
• CPC Class Codes: G09G 5/14 Display of multiple viewports
• CPC Class Codes: G09G 5/397 Arrangements specially adapted for transferring the contents of two or more bit-mapped memories to the screen simultaneously, e.g. for mixing or overlay G09G5/02 takes precedence

Abstract

A graphic display control system performs multi-window display at a workstation or the like. The graphic display control system comprises image display means whose display screen is composed of a plurality of pixels or character sections; at least two image storage means each of which has a storage capacity for one display screen of the image display means; two image selection information storage means which store image selection information for selecting one of the at least two image storage means for one pixel or one character section composing one display screen of the image display means; selection information output means which selects one of the two image selection information storage means and outputs the image selection information stored in the selected image selection information storage means; and image selection output means which selects one of the at least two image storage means for one pixel or one character section on the basis of the image selection information outputted by the selection information output means, and outputs the image information stored at the pixel position or character position corresponding to the selected image storage means to the image display means.

Claims

1. A graphic display control system which performs multi-window display, comprising:

image display means for providing a display screen composed of a plurality of pixels or character sections;

at least two image storage means for storing image information, each of said at least two image storage means having a storage capacity for the display screen of said image display means;

two image-selection-information storage means for storing image-selection information the image-selection information in each image-selection-information storage means selecting one of said at least two image storage means at every pixel or every character section of a portion of the display screen of said image display means;

selection information output means for receiving a selection indication signal, for selecting a first one of said two image-selection-information storage means according to the selection indication signal, and for outputting the image-selection information stored in the first one of said image-selection-information storage means;

control means for writing new image-selection information to a second one of said image-selection-information storage means, and for outputting the selection indication signal to said selection information output means to alternate selection between said two image-selection-information storage means when writing of the new image-selection information is completed; and

image selection output means for selecting one of said at least two image storage means at every pixel or every character section based on the image-selection information outputted by said selection information output means, and for outputting the image information stored in the one of said at least two image storage means to said image display means.

2. A graphic display control system according to claim 1,

wherein said image display means produces a vertical synchronization signal, and

wherein after receiving the selection indication signal from said control means, said selection information output means selects the second one of said two image-selection-information storage means in synchronization with the vertical synchronization signal received from said image display means, and outputs the image-selection information stored in the second one of said image-selection-information storage means.