CN102768655B - JAVA-based display method of Mongolian - Google Patents

Abstract

The invention discloses a JAVA-based display method of Mongolian. A font engine capable of providing an interface to access a Mongolian OpenType font library is compiled with JAVA language. Input alphabetic coding strings accord to national standard is output as corresponding Mongolian display character graphics. The font engine is a relative independent function in a format of Font. drawText (text, compatiblePath), wherein text is input Unicode character strings and font graphics are output to compatiblePath through the function. The function is applicable to all environments support JAVA. By the JAVA-based display method which is widely applicable, researches and developments of Mongolian information processing are facilitated.

Description

Mongolian Display Method Based on JAVA

technical field

The invention relates to a Mongolian display method, in particular to a JAVA-based Mongolian display method.

Background technique

Mongolian is a phonetic script. The unique phenomenon of "one sound with multiple shapes and one shape with multiple sounds" in Mongolian has made Mongolian recognized as the most complex text in information processing in the world. my country has started research on Mongolian information processing since the late 1970s. At that time, there was no unified international or national standard for Mongolian character encoding, and developer-defined encoding was generally used. With the formulation of the international standard ISO/IEC10646 and the national standard GB13000, Mongolian characters have a unified standard encoding. More and more attention has been paid to how to apply Mongolian international or national standard coding in information processing. In current international or national standards, Mongolian letters are determined according to pronunciation. However, the writing of Mongolian words is very different from other phonetic characters. When Mongolian words are written, they are not displayed according to the Mongolian characters defined in the international or national standards, but are displayed by the deformed characters of these letters. The Mongolian characters defined in international or national standards are usually called "nominal characters", and the deformed characters of the "nominal characters" used for display are called "deformed display characters". Most of the "nominal characters" have more than 2 "deformed display characters", up to 9 "deformed display characters". The shape of each "nominal character" is different, but the shapes of the "deformed characters" corresponding to different "nominal characters" have the same font appearance. such as letters The deformation has letter The deformation has If the same glyph is not considered, the number of "deformed characters" corresponding to each "nominal character" can reach nearly 1,000. According to the grammar of Mongolian word formation, the shape of the letters that make up a Mongolian word is different in different positions of the word (word beginning, word middle, word end); the shape of the letters adjacent to it may also be different. When some characters are adjacent in a word, a combined deformation will be produced and become a combined character. like followed by will combine into (in words) or (end of word). Therefore, when using the Mongolian standard encoding, it is necessary to clarify which "deformation character" should be used when the "nominal character" appears in a word, and it is more important to have an engine that can correctly interpret these complex transformations.

In the prior art, a function library called Pango is used in the Linux system to display complex text, and this technology implements the above functions by parsing the OpenType font library. This technology can only be applied to the Linux platform, and especially important: this technology does not support the display of Mongolian.

Contents of the invention

In order to solve the above-mentioned technical problems, the present invention provides a Java-based Mongolian display method, which is mainly realized by a processing engine capable of parsing the nominal characters of the Mongolian Opentype font library and the mapping rules of deformed and displayed characters. The engine can be used on mobile phones and other mobile devices that support the operation of JAVA programs to use Mongolian coded in accordance with international or national standards, thereby realizing the direct exchange of Mongolian information between mobile devices and computers.

Its technical scheme is as follows:

A method for displaying Mongolian based on JAVA, comprising the following steps:

Set up Mongolian font engine, described font engine is a relatively independent function, function format is: Font.drawText (text, compatiblePath), parameter text is the national standard code character string of input, function output font figure to compatiblePath;

A font engine that provides an interface to access Mongolian OpenType fonts:

The Mongolian font engine is introduced into the application program, and the Path interface used for drawing is realized. After calling the Font.drawText (text, compatiblePath) function, the font graphics that meet the current application environment are automatically generated, and it is drawn to the required The location is fine. In addition, the caller can use any feasible method in this environment to rotate, scale, and arbitrarily deform the font. Due to the characteristics of the graphics, these transformations will not have any impact on the quality of the font, which can fully satisfy the user. Any typesetting requirements.

Character attribute annotation:

Mapping of characters to glyph numbers: a data table called cmap (character mapping) is included in the font file, which contains the matching relationship between each character and its corresponding default character;

Glyph replacement: the first step is to find the glyph or glyphs to be replaced, and the second step is to perform the replacement;

Glyph drawing: Define a drawing interface to abstract the drawing work into a number of functions to be implemented. When filling the glyphs, use the "odd-even rule" to fill the glyphs, that is, complete the glyph drawing work.

The method for determining whether a point in the glyph is filled is as follows in the present invention: take the investigation point as the starting point, lead a ray (direction is arbitrary), initialize the counter to be 0, when the ray passes through the outline (no matter how the direction is), the counter adds 1, and finally when Fill the dot when the counter is odd.

Modern fonts use outline descriptions. When drawing glyphs, you only need to draw the outline, and then fill the outline with color. Since the methods of drawing graphics are different in different application environments, an interface for drawing graphics is defined here. This interface only defines basic drawing methods such as drawing straight lines and curves. To implement this interface, you generally only need to directly call the corresponding method in the environment. When filling the glyphs, use the "odd-even rule" to fill, that is, to complete the glyph drawing work. The method of determining whether a point in the glyph is filled is as follows: start from the inspection point, draw a ray (in any direction), initialize the counter to 0, when the ray passes through the outline (regardless of the direction), add 1 to the counter, and finally Fill the dot when the counter is odd.

Beneficial effects of the present invention:

The present invention can be applied to mobile phones, mobile devices, and even network environments that support the operation of Java programs, and can realize the storage, display, and output of Mongolian characters according to Mongolian international or national standard codes, and realize the communication between mobile devices such as mobile phones and computers, mobile devices, etc. direct exchange of information in Mongolian. It can be beneficial to the research and development of Mongolian information processing, and is conducive to enhancing the communication between various ethnic groups. Most mobile phones support Java technology at present, so the present invention has extensive application environment and potentiality.

Description of drawings

Fig. 1 is a flow chart of font engine processing in the present invention;

Fig. 2 is a logical structure diagram of a replacement rule in the present invention.

Detailed ways

The method of the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Due to the ubiquitous phenomenon of "one sound with multiple forms and one form with multiple sounds" in Mongolian words, the processing of Mongolian words is much more complicated than that of other languages. The glyphs of Mongolian characters will change with their positions in the word, and most of the changes have certain regularity, and some of the change rules are ambiguous, which can be distinguished by special control symbols. Usually, people's understanding of the font is that the font only contains the data of the character shape and its corresponding code, the program sends the character code into the font, and the font returns the corresponding glyph data. The Mongolian Opentype font library not only stores the glyph data and nominal character codes of characters, but also includes the description of the mapping relationship between Mongolian nominal characters and their deformed characters. Only nominal characters have codes, and deformed characters have no codes. . Which deformation is used for each nominal character at different positions in the word, which deformation is used after a character is followed by a certain character or which characters (strings), and which shape a character is forced to use in a word, etc. need to give a complete information description .

Fig. 1 is a schematic diagram of the processing flow of the present invention. The invention is a font engine written in JAVA language and capable of providing an interface to access the Mongolian OpenType font library. It is externally displayed as inputting a Mongolian letter code string that meets the national standard, and outputting the corresponding Mongolian deformation display character graphics. The font engine is a relatively independent function, the function format is: Font.drawText(text, compatiblePath), text is the input national standard code string, and the function outputs glyph graphics to compatiblePath. This function can be applied in all environments that support Java. First read in the string to be drawn, analyze the input string, determine the attributes of each character in it, and mark it; then map the character code to the font serial number; then according to the font replacement rules and the character attributes marked in the first step , to change the glyphs that make up the string into the correct form; finally, the required glyphs are drawn and output. This completes the entire process.

The technical implementation plan is as follows:

Character attribute annotation: In Mongolian, letters will have different glyphs depending on where they appear in the word, and the addition of control characters makes it more complicated. When converting characters to default glyph numbers, the Some information may be lost, so character attributes are annotated before conversion to glyph numbers, including:

SUBST_NODO＝1; //Non-Mongolian

SUBST_MEDI = 1 < < 1; // word in

SUBST_INIT=1<<2;//prefix

SUBST_FINA = 1 < < 3; // end of word

SUBST_ISOL = 1 << 4; //Subst_ISOL

The size of the attribute values listed above is meaningful. In the process of glyph fit replacement, the position of the character in the word may change, so a method for determining the final attribute of the glyph after the fit is needed. Regulations: (except in special cases) the maximum attribute value of all glyphs participating in the combination is the attribute value of the combined glyph.

The attributes of a character are also the attributes of the corresponding glyph.

Example: string The national standard code is "0x1836 0x1821 0x182c 0x1821", and the attributes are marked according to the location of the characters as shown in Table 1:

National standard code 0x1836 0x1821 0x182c 0x1821 Attributes SUBST_INIT SUBST_MEDI SUBST_MEDI SUBST_FINA

Table 1

Mapping of characters to glyph numbers: Glyph numbers are the input data for glyph replacement, and also the only parameter for extracting glyph outline data from font files. If you want to further process, you must complete this step of conversion.

The font file contains a data table called cmap (character map), which contains the matching relationship between each character and its corresponding default character. Logically it is a data dictionary. The logical structure of cmap is:

Therefore, to complete the mapping from characters to glyph numbers, you only need to correspond one-to-one according to the above table.

The result of executing the mapping in the above example may be as shown in Table 2:

National standard code 0x1836 0x1821 0x182c 0x1821 Attributes SUBST_INIT SUBST_MEDI SUBST_MEDI SUBST_FINA glyph number 314 185 255 185

Table 2

Glyph replacement: The complexity of displaying traditional Mongolian is that characters have different appearances in different positions, and some characters will have different forms when combined. This is achieved by using glyph replacement.

The so-called glyph replacement is to replace one or some glyphs with some other glyphs. The entire replacement process can be divided into two steps. The first step is to find the glyph or characters to be replaced, and the second step is to perform the replacement.

Glyph substitution is rule-driven. The logical structure of the glyph substitution rules is as follows.

The execution condition is one of the following:

SUBST_MEDI=1<<1;//Glyphs are in words

SUBST_INIT=1<<2;//The font is at the beginning of the word

SUBST_FINA=1<<3;//The font is at the end of the word

SUBST_ISOL=1<<4;//Glyph is an independent form

SUBST_ALL=SUBST_MEDI|SUBST_INIT

|SUBST_FINA|SUBST_ISOL;//No matter what type of font is

The first four are character attributes, and the last one is a combination of them.

The so-called fulfillment of the execution condition means that the attributes of the glyph to be replaced must meet the execution condition, and if not, no replacement will be performed even if the description of the replacement target is met.

The logical structure of the replacement target description is as follows:

The replacement target description can be expressed as: if the current sequence is xxx, preceded by xxx, and followed by xxx, then the current sequence will be replaced.

It can be omitted when the front and back glyphs are not concerned, and can be simplified when the target glyph sequence to be replaced is one glyph, thus forming three variants. The conditional replacement is called Type6; the unconditional but many-to-one replacement is called Type4; the unconditional and one-to-one replacement is called Type1.

OpenType fonts organize all substitution rules into GSUB data tables. For data tidiness and compression, OpenType uses the hierarchical structure shown in Figure 2 to save the replacement rules.

Among them, "property" represents the execution condition.

The "lookup table" contains replacement rule data, and uses Type1, Type4 or Type6 description forms according to content requirements.

The "sub-lookup table" is where the replacement rule data is actually saved, and it has different physical storage formats.

The features used in traditional Mongolian are shown in Table 3, and their corresponding execution conditions are also listed in the table.

table 3

The order in which the rules are applied when glyphs are replaced is also the same as the above table, and the order cannot be confused.

The glyph replacement process is as follows:

As in the above example, the following rules may be involved, as shown in Table 4:

Table 4

Then the replacement result is: 315 190 777

Font drawing: use the outline font TrueType format, use 1 to 2 order Bezier curves to describe the outline, this step is related to the application environment, the method of drawing graphics in different application environments is not the same, the present invention defines a drawing interface (Path) The drawing work is abstracted into several functions to be realized, so that the present invention can be used in different application environments.

The method for determining whether a point in a glyph is filled is as follows:

Starting from the inspection point, lead a ray (in any direction), initialize the counter to 0, when the ray passes through the contour (regardless of the direction), the counter is incremented by 1, and finally fill the point when the counter is an odd number.

Utilizing the technical scheme of the invention, Mongolian application software on mobile devices can be developed. As long as the Mongolian code conforming to the national standard code is used on the mobile device, the Mongolian Opentype font library must be used, so the invention needs to be used to read and display (output) the Mongolian language in the font library. For example, to develop Mongolian electronic dictionary software on a mobile phone, now save the English, Mongolian and Chinese entry files and the Mongolian Opentype font file stored in accordance with the national standard code into the memory of the mobile phone, and then write the Mongolian input method and read from the font Both Mongolian and Mongolian display need to use the present invention. Other applications, such as receiving and sending Mongolian mobile phone text messages, using mobile phones to receive and send Mongolian e-mails, mobile phone browsing Mongolian web pages, using Mongolian on mobile phones to interact with computer network sites, using the present invention, can use mobile phones to create , Edit Mongolian files that can be used on other mobile devices, computers and computer networks, etc., are similar to the application process of electronic dictionaries; in addition, the present invention is also one of the feasible solutions for cross-platform display of Mongolian on web pages.

Claims (1)

1. a method for displaying Mongolian based on JAVA, is characterized in that, comprises the following steps: Set up Mongolian processing font engine, described font engine is a relatively independent function, function format is: Font.drawText (text, compatiblePath), text is the national standard code character string of input, function output font figure to compatiblePath; Provide an interface to access the font engine of the Mongolian OpenType font library: introduce the Mongolian processing font engine into the application program, and realize the Path interface for drawing, after calling the Font.drawText(text, compatiblePath) function, automatically generate a corresponding Font graphics of the current application environment; Character attribute annotation: Annotate the attributes of characters before converting to glyph numbers, these attributes include: The characters are not Mongolian characters, the characters appear in the middle of the word, the characters appear at the beginning of the word, the characters appear at the end of the word, the characters are independent words, and the attributes of the characters are also the attributes of the corresponding glyphs; Mapping of characters to glyph numbers: the font file contains a data table called character mapping, which contains the matching relationship between each character and its corresponding default character; Glyph replacement: the first step is to find the glyph or glyphs to be replaced, and the second step is to perform the replacement; Glyph drawing: define a drawing interface to abstract the drawing work into several functions to be implemented, and use the "odd-even rule" to fill the glyphs, that is, complete the glyph drawing work; In glyph drawing, the method to determine whether a point in the glyph is filled is as follows: start from the inspection point, draw a ray, initialize the counter to 0, when the ray passes through the outline, add 1 to the counter, and finally fill the ray when the counter is an odd number point.