Bi-directional text support in legacy applications

• US 6,910,185 B1
• Filed: 04/25/2000
• Issued: 06/21/2005
• Est. Priority Date: 04/25/2000
• Status: Expired due to Term

• Current Assignee: Unwired Planet LLC (JP Morgan Chase & Co)
• Original Assignee: Openwave Systems Incorporated (JP Morgan Chase & Co)
• Inventors: Schwartz, Bruce V.
• Primary Examiner(s): Feild, Joseph
• Assistant Examiner(s): Smith, Peter J.
• Application Number:
  US09/558,476
• Time in Patent Office: 1,883 Days
• Field of Search: 715/536, 715/531, 715/538
• US Class Current: 715/205
• CPC Class Codes: G06F 40/103 Formatting, i.e. changing of presentation of documents automatic justification G06F40/189; automatic line break hyphenation G06F40/191
• CPC Class Codes: G06F 40/232 Orthographic correction, e.g. spell checking or vowelisation
• CPC Class Codes: G06F 40/284 Lexical analysis, e.g. tokenisation or collocates

Abstract

A method and apparatus for support of bi-directional text in legacy applications is disclosed. The method may be used in different embodiments for either monospace or proportionally spaced fonts. In general, the method involves first flipping all of the text, and thereby putting most of the text into its proper position and orientation. The method then involves finding any foreign (left-to-right) text within the flipped text, and flipping it back.

Claims

1. A method implemented in a processing system comprising:

receiving a line of text, the line of text having a set of ordered characters having an original order and orientation;

flipping the characters of the line of text about a display axis;

identifying in the line of text a group of adjacent characters that share a characteristic not shared by at least one other character in the line of text; and

flipping the characters of the group of adjacent characters about a vertical axis which passes through the group of adjacent characters so that the group of adjacent characters returns to the original order and orientation.

2. The method of claim 1 further comprising:

receiving a block of text;

breaking the block of text into a set of lines of text; and

performing said receiving the line of text, flipping the characters of the line, identifying and flipping the group of adjacent characters, for each line of text of the set of lines of text.

3. The method of claim 2 further comprising:

displaying the line of text on a display device after said flipping the group of adjacent characters.

4. The method of claim 1 wherein:

the line of text is received from an application with no capability of handling bi-directional text.

5. The method of claim 1 wherein:

the group of adjacent characters are in a language which is normally read left-to-right.

6. The method of claim 1 wherein:

the group of adjacent characters are in a language which is normally read right-to-left.

7. A method as recited in claim 1, wherein the display axis is a center vertical axis of a display on which the line of text is to be displayed.

8. A method as recited in claim 1, wherein the characteristic is a left/right directionality of the characters of the group of adjacent characters.

9. A method as recited in claim 8, wherein said generating a set of runs comprises:

identifying any runs of foreign characters which span two lines in the block of text;

splitting each run of foreign characters which spans two lines in the block of text, if any, into two strings, one string on each of the two lines.

10. A method as recited in claim 8, wherein said flipping at least one run of characters about a vertical axis within the run of characters comprises flipping a run of characters, which has a different left-right characteristic than surrounding characters, about a vertical axis within the run of characters.

11. A machine-readable medium storing instructions, which, when executed by a processor, cause the processor to perform a process comprising:

receiving a line of text, the line of text having a set of ordered characters having an original order and orientation;

flipping the characters of the line of text about a center vertical axis of a display on which the line of text is to be displayed;

identifying a set of runs of foreign characters in the line of text; and

for each identified run of foreign characters in the identified set, if any, flipping the run of foreign characters about a center vertical axis of the run of foreign characters so that the run of foreign characters returns to the original order and orientation.

12. The machine readable medium of claim 11 further storing instructions which when executed by the processor, cause the processor to perform a process comprising:

receiving a block of text;

breaking the block of text into a set of lines of text; and

performing said receiving the line of text, flipping the characters of the line,

identifying and flipping the run of foreign characters, for each line of text of the set of lines of text.

13. The machine readable medium of claim 11 further storing instructions which when executed by a processor, cause the processor to perform the method further comprising:

passing the line of text to a native operating system for display.

14. A method implemented in a processing system comprising:

receiving a line of text, the line of text having a set of ordered characters having an original order and orientation;

flipping the characters of the line of text about a center vertical axis of a display on which the text is to be displayed;

identifying zero or more runs of foreign characters in the line of text; and

for each identified run of foreign characters in the line of text, if any, flipping the characters of the run of foreign characters about a center vertical axis of the run of foreign characters so that the run of foreign characters returns to the original order and orientation.

15. The method of claim 14 wherein the method further comprises:

receiving a block of text;

breaking the block of text into a set of lines of text; and

performing said receiving the line of text, flipping the characters of the line,

identifying and flipping the characters of the runs of foreign characters for each line of text of the set of lines of text.

16. The method of claim 15 wherein the method further comprises:

passing the line of text to a native operating system for display.

17. A processing system comprising:

a processor;

a display device; and

a memory storing instructions which, when executed by the processor, cause the system to perform a process which includes

receiving a line of text, the line of text having a set of ordered characters having an original order and orientation;

flipping the characters of the line of text about a vertical center axis of the display device;

identifying a run of foreign characters in the line of text; and

flipping the characters of the run of foreign characters about a center vertical axis of the run of foreign characters so that the run of foreign characters returns to the original order and orientation.

18. The processing system of claim 17 wherein the process further comprises:

receiving a block of text;

breaking the block of text into a set of lines of text; and

performing said receiving the line of text, flipping the characters of the line,

identifying and flipping the characters of the run of foreign characters, for each line of text of the set of lines of text.

19. The processing system of claim 18 wherein the process further comprises:

passing the line of text to a native operating system for display.

20. The processing system of claim 19 wherein the processing system is a mobile device.

21. The processing system of claim 19 wherein the processing system is a mobile wireless device.

22. A method implemented in a processing system comprising:

receiving a line of text, the line of text having a set of ordered characters having an original order and original orientation;

generating a set of runs within the line of text;

flipping a location and an orientation of each run of the set of runs about a center vertical axis of a display; and

identifying a set of runs of foreign characters within the line of text;

flipping the orientation of each run of foreign characters about a vertical axis within the run of foreign characters so that the run of foreign characters returns to the original order and original orientation.

23. The method of claim 22 further comprising:

rendering each run of the set of runs, except for the runs of foreign characters, in a first orientation; and

rendering each run of foreign characters in a second orientation.

24. The method of claim 23 further comprising:

receiving a block of text having a set of ordered characters and a location; and

breaking the block of text into a set of lines of text, each line having a set of ordered characters and a location.

25. The method of claim 24 wherein:

the text is received from an application with no capability of handling bi-directional text.

26. The method of claim 25 wherein:

the foreign characters are characters which are normally read left-to-right.

27. The method of claim 25 wherein:

the foreign characters are characters which are normally read right-to-left.

28. A method implemented in a processing system comprising:

receiving a block of text including a plurality of lines of text, each line including a plurality of ordered characters having an original order and orientation;

breaking the block into a plurality of lines of text;

for each of the lines of text into which the block of text has been broken;

determining a set of runs of characters within the line of text, including identifying left-right characteristics of each of the runs of characters;

flipping a location and an orientation of each run of characters about a center vertical axis of a display; and

rendering each of the runs of characters on the display in accordance with the left-right characteristics of the run, including flipping at least one run of characters about a vertical axis within the run of characters so that the run of foreign characters returns to the original order and orientation.