Display with enhanced scrolling capabilities

• US 5,038,138 A
• Filed: 04/17/1989
• Issued: 08/06/1991
• Est. Priority Date: 04/17/1989
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Busboom, Leah J. H., Maitland, William J. Jr., Akiyama, Alex A.
• Primary Examiner(s): Oberley, Alvin E.
• Assistant Examiner(s): Wu, Xiao Min
• Application Number:
  US07/339,346
• Time in Patent Office: 841 Days
• Field of Search: 340/726, 340/721, 340/724, 340/709, 340/723
• US Class Current: 345/684
• CPC Class Codes: G09G 5/14 Display of multiple viewports

Abstract

A computer display has a display processor connected to a presentation space buffer and a screen buffer. The presentation space buffer is larger than the screen buffer, and is divided into a plurality of partitions. Each partition has a partition window which maps into the screen buffer. If a partition is active, its associated partition window is written into the screen buffer at the mapped location. The screen buffer periodically refreshes the display screen, so a plurality of partition windows are displayed to the computer user. One or more scroll groups can be defined, and one or more partitions can be assigned to each scroll group. Each defined scroll group has a vertical scroll trigger and a horizontal scroll trigger. The display monitors the movement of the cursor within a partition window. When the cursor gets close enough to a boundary of a partition window, to trigger a scroll trigger, the display shifts the partition window within its partition and writes this updated partition window into the screen buffer. Updated partition windows are written into the screen buffer for the other partitions in the scroll group.

Claims

1. A computer display having a display screen and a cursor, comprising:

a display processor;

a screen buffer, connected to said display processor;

a presentation space buffer, connected to said display processor, said presentation space buffer being larger than said screen buffer;

means for defining a first partition and a second partition in said presentation space buffer;

first writing means for writing a first partition window from said first partition to said screen buffer;

second writing means for writing a second partition window from said second partition to said screen buffer;

means for defining a first scroll group containing a first scroll trigger, said first scroll group comprising said first and second partitions;

means for shifting said first and second partition windows simultaneously in response to said first scroll trigger; and

means for displaying said screen buffer on said display screen.

2. The computer display of claim 1 further comprising:

means for locating said cursor in said first partition window;

means for shifting said first partition window in said first partition when said cursor triggers said first scroll trigger;

means for writing said shifted first partition window to said screen buffer; and

means for refreshing said display screen with said screen buffer.

3. The computer display of claim 2, further comprising:

means for shifting said second partition window in said second partition when said cursor triggers said first scroll trigger; and

means for writing said shifted second partition window to said screen buffer.

4. The computer display of claim 3, wherein said first scroll group defining means further contains a first scroll amount.

5. The computer display of claim 4, wherein said shifted first partition window is displaced from said first partition window by said first scroll amount.

6. The computer display of claim 5, wherein said shifted second window is displaced from said second partition window by said first scroll amount.

7. The computer display of claim 1, further comprising:

means for defining a second scroll group containing a second scroll trigger.

8. The computer display of claim 7, further comprising:

means for defining a third partition in said presentation space buffer; and

means for assigning said third partition to said second scroll group.

9. The computer display of claim 8, further comprising:

means for locating said cursor in said first partition window;

means for shifting said first partition window in said first partition when said cursor triggers said first scroll trigger;

means for writing said shifted first partition window to said screen buffer; and

means for refreshing said display screen with said screen buffer.

10. The computer display of claim 9, further comprising:

means for locating said cursor in said third partition window;

means for shifting said third partition window in said third partition when said cursor triggers said second scroll trigger; and

means for writing said shifted third partition window to said screen buffer.

11. The computer display of claim 10, wherein said first scroll group defining means further contains a first scroll amount.

12. The computer display of claim 11, wherein said second scroll group defining means further contains a second scroll amount.

13. The computer display of claim 12, wherein said shifted first partition window is displaced from said first partition window by said first scroll amount.

15. A computer system having a workstation controller connected to a display having a display screen and a cursor, said display comprising:

a display processor;

a command buffer, connected to said display processor;

a screen buffer, connected to said display processor;

a presentation space buffer, connected to said display processor, said presentation space buffer being larger than said screen buffer;

means in said workstation controller for sending a define presentation space command to said command buffer;

means in said display for dividing said presentation space buffer into a first partition and a second partition responsive to said define presentation space command in said command buffer;

means in said workstation controller for writing data to said presentation space buffer;

means in said display for writing a first partition window from said first partition to said screen buffer;

means in said workstation controller for sending a define scroll group command to said command buffer;

means in said display for defining a scroll group containing a scroll trigger, said scroll group comprising said first and second partitions, said means being responsive to said define scroll group command in said command buffer; and

means in said display for shifting said first and second partition windows simultaneously in response to said first scroll trigger; and

means in said display for displaying said screen buffer on said display screen.

14. The computer display of claim 15, wherein said shifted third partition window is displaced from said third partition window by said second scroll amount.

16. The computer system of claim 15, further comprising:

means in said workstation controller for sending an assign scroll group partition command to said command buffer; and

means in said display for assigning said first partition to said scroll group.

17. The computer system of claim 16, further comprising:

means in said display for locating said cursor in said first partition window;

means for writing a shifted first partition window from said first partition to said screen buffer when said cursor triggers said scroll trigger; and

means for refreshing said screen buffer on said display screen.

18. The computer system of claim 17, wherein said scroll group defining means further contains a scroll amount.

19. The computer system of claim 18, wherein said shifted first partition window is displaced from said first partition window by said scroll amount.

20. The computer system of claim 15, further comprising:

means in said workstation controller for locating said cursor in said presentation space buffer; and

means in said workstation controller for updating said presentation space buffer when said cursor is located at the boundary of said presentation space buffer.

21. A method for scrolling in a computer display having a display processor, a screen buffer, a presentation space buffer larger than said screen buffer, a display screen and a cursor, the method comprising the steps of:

defining a first partition and a second partition in said presentation space buffer;

writing a first partition window from said first partition to said screen buffer;

writing a second partition window from said second partition to said screen buffer;

defining a first scroll group containing a first scroll trigger, said first scroll group comprising said first and second partitions;

shifting said first and second partition windows simultaneously in response to said first scroll trigger; and

displaying said screen buffer on said display screen.

22. The method of claim 21, further comprising the steps of:

locating said cursor in said first partition window;

shifting said first partition window in said first partition when said cursor triggers said first scroll trigger;

writing said shifted first partition window to said screen buffer; and

refreshing said display screen with said screen buffer.

23. The method of claim 22 further comprising the steps of:

shifting said second partition window in said second partition when said cursor triggers said first scroll trigger; and

writing said shifted second partition window to said screen buffer.

24. The method of claim 21 further comprising the step of:

defining a second scroll group containing a second scroll trigger.

25. The method of claim 24, further comprising the steps of:

defining a third partition in said presentation space buffer; and

assigning said third partition to said second scroll group.

26. The method of claim 25, further comprising the steps of:

locating said cursor in said first partition window;

shifting said first partition window in said first partition when said cursor triggers said first scroll trigger;

writing said shifted first partition window to said screen buffer; and

refreshing said display screen with said screen buffer.

27. The method of claim 26, further comprising the steps of:

locating said cursor in said third partition window;

shifting said third partition window in said third partition when said cursor triggers said second scroll trigger; and

writing said shifted third partition window to said screen buffer.