JPH023091A - Apparatus and method for generating character - Google Patents

Abstract

PURPOSE: To improve the efficiency of CPU time by storing an address for an instruction to be used for forming each character and a parameter necessary for the instruction in a storage area of each character in a font. CONSTITUTION: A monitor program 122 in a memory program 110 prepares a color register for a graphic controller 102 in a system. Information indicating which character is to be plotted or how many characters are to be plotted is extracted from a central processing unit(CPU) 100 and an address in a font index table 114 which stores the information of a character concerned is calculated for every character. A plotting program 124 searches a character table 116 for the character to be plotted and extracts a necessary parameter. Then, the parameter is converted, a routine for executing a graphic primitive 126 necessary for mapping on a mappling display device 104 is accessed and the conversion and graphic primitive are executed until the plotting of the character. Consequently each character can be generated at real time.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION This invention relates to the generation of characters, and more specifically, in broad terms, to the generation of characters on a digital computer system using a mapping graphical display. The present invention relates to an apparatus and method for generating and displaying.

[Prior Art] A method for generating characters in a computer system using a mapping graphic display device is a method for generating characters in a computer system, of which various types are currently known. set, but some computers use only one of these fonts,
Other computers allow the operator or programmer to select one of several fonts. Additionally, the advent of mapping graphics displays allows computers to generate a variety of font types and display them within a single image.

The term "mapping" refers to a method of storing and accessing data in display memory.

For example, in a bit mapping display device, the video screen can be thought of as an array of pixels.

A certain screen has 100 pixels (vertical direction) x 100
pixels (in 811 directions), the memory storage location corresponds to the number of pixels on the screen.
It becomes 0 pieces. The association of each storage location in memory with a particular pixel location on the screen of a display device is referred to as "mapping."

One way to represent characters is to use character bit maps. Processing of this character bit map is accomplished by storing a pattern representing each character's type, size, and face in a section of memory (also called "character memory"). Each character that is displayed or printed is It can be thought of as existing in a two-dimensional pixel matrix (also called "cell j"). The bit patterns representing the cells are stored in character memory.
This is typically done by storing a collection of patterns in character memory. This collection of bit patterns typically includes characters such as letters, numbers, and punctuation marks, as well as certain commonly used symbols.

After the r bitmaps of a character are stored in the rcharacter memory, the bitmaps must be sent to the screen in the desired order. That is, the bit map information must be used in some way to form the desired sequence of characters so that it can be recognized as a word, sentence, or other structure. Several methods are known for performing this transfer.

One method is to use a "block copy" operation to transfer a bit map from character memory to a display device.
reads a bit map of characters from character memory.
The CPU then writes the character bit map to the display memory driver circuit, which transfers the bit map to the display memory.

Another known method of transferring bit map information is to use a display driver to retrieve character bit maps directly from memory. When using this method, CP
tT passes the character output command and the start address of the character bit map to the display driver, and in response to this, the display driver directly takes out the bit map and writes it to the display memory.

Another known method of transferring bit map information is
"Pixel data management program" and "macro instructions"
This is done using the . This method, along with several other methods, is described in US Pat. No. 4,622,546 (Sfarti et al.).

[Invention tries to solve! fl] All of the above-mentioned known methods have in common that they use a character bit map as a necessary component for font generation. In general, there are several problems with systems that use character bit maps. One of the common problems with zero character bit map devices is that when creating a character, the CPU It is necessary to execute memory access instructions. This burden is transferred to the CPU
This is the cause of deteriorating system performance (IA management efficiency). The bit map method is also subject to memory space constraints since a memory location must be allocated for each required character.

Further, the bit map method cannot provide flexibility because it is often cumbersome to generate changes to a character or an entire font pixel by pixel.

Since the characters themselves in the bit map format have limitations, operations such as scaling (enlarging or reducing the character size) and rotation (generating words, character strings, or characters at an angle with respect to a reference line) are not possible. It is difficult and costly. For example, when enlarging a bit map character, if you perform an enlargement operation (copying pixel data is a typical example), the edges of the character will appear fuzzy. Sometimes. Storing a separate font with enlarged bitmaps would solve this problem, but would require more memory space. Furthermore, character rotation using the bit map method is performed by a block copy operation, which is difficult to rotate and requires a large number of calculations.

Therefore, a font generation system and method that does not use bit map character storage is desired. Furthermore, it is fast, flexible, and generates a wide variety of fonts while efficiently using both memory space and CPU time.
What is desired is a font generation method that can be used to perform the conversion.

The present invention provides a system and method for storing fonts and generating characters.

SUMMARY OF THE INVENTION Rather than storing a bit map, the storage for each character in a font contains the addresses of the instructions used to form the character and the addresses of those instructions. Save the necessary parameters.

According to one embodiment of the present invention, for each character, an index table for a font includes information such as the address of the character's graphical element or pixel (primitive) table (character table), and information about how much information the character has in the character table. It contains details of how the data is stored and the axes regarding character base offset and cell size. The character table for each character contains the address of the macrocode instruction followed by the parameters necessary to generate the character. Any number of actions can be defined to create the 0 character. 0 For example, the line It goes without saying that any geometric shape can be drawn as a primitive, such as drawing a spline, drawing a spline, drawing a circle, drawing an ellipse, drawing a rectangle, drawing a single pixel, drawing a flood fill, etc. be. These IA locations are called graphical primitives and can be executed in any order and with any redundancy. Thus, the present invention allows programmers and operators to design and use a wide variety of fonts and to dynamically change these fonts with relatively little programming effort.

Furthermore, because the present invention uses graphics primitives, memory space and time can be used efficiently.

The use of graphic primitives in font generation and storage offers several advantages over traditional bit map systems. These advantages are particularly noticeable in the areas of scaling and rotation. Graphic primitives also allow character generation to be independent of orientation and size.
For example, for a character that needs to draw a straight line, you only need to provide the relative start and end points, and when you want to rotate a line, you only need to provide several different line end parameters in the line drawing operation. That's fine. This makes it easier to rotate characters and strings. Additionally, text scaling becomes easier. That is, the same primitive used to draw a line can be used to draw longer or shorter lines by simply changing the endpoints.

According to the present invention, since a two-dimensional conversion method is used, conversion operations such as scaling (changing the size of characters) and rotation (drawing words, character strings, and characters at an angle) can be easily performed. Character size can be changed or rotated simply by manipulating the parameters given to the primitive during drawing operations.0 The advantage of the present invention is that it is not necessary to change the primitive or parameter itself, or the primitive execution order of a certain character. In the embodiment of the present invention, these transformation functions are performed using a well-known two-dimensional transformation technique using matrix multiplication.

According to the present invention, there is no need to keep multiple font bit maps in memory; in fact, the generation of a character occurs at the time of its drawing. This method has the advantage that multiple fonts can be stored and generated based on commands that indicate the graphic primitives stored as a collection and the order in which they are executed. In addition, factors such as size, rank, and rotation can influence
It has the advantage that it can be changed simply and dynamically by manipulating the parameters passed to the primitive. Additionally, the present invention has the advantage of improving memory usage efficiency when storing a given number of fonts, as well as reducing CPU overhead when generating and drawing fonts, compared to pit map systems.

[Embodiment] According to an embodiment of the present invention, a computer-based microcode program is used to create a graphic image.
The program runs on a graphics processor that uses primitives to store fonts and generate characters. Although it is desirable to code the operations described in ``Kimei 1n'' at the microinstruction level for speed, these operations can easily be performed in any programming language at either the micro or macro level. Of course, coding is possible. Furthermore, the invention can be implemented in hardware or using programmable logic circuits.

The present invention will first be described in detail with reference to FIG. 1. The present invention provides a system and method for storing fonts and generating characters. The storage area for each character in a font does not contain a bit map, but rather the addresses of the instructions used to create the character and the parameters needed by these instructions.
It uses memory tables to store information used in character generation and programs to read and use that information. The system transfers character code information to the CPU and input/output devices (through these programs and tables).
(e.g. keyboard), or perform conversion operations on character data at the time the characters are generated on the display device.

As shown in the preferred embodiment of FIG.
02 (that is, a device for processing and displaying data in memory), a mapping display device 104 (such as a high-resolution bit map display device), and an input/output device and controller 106 (such as a keyboard, disk, printer, etc.). ), program memory 110, and global memory 108 (for storing tables, pointers, scratchpads, and other information used by the program). Global memory 108 and program memory 110 may each be separate physical memories or may be defined as storage within a single memory. Both global memory and program memory are static RAM (
Display device 104, which is preferably a high speed memory such as SIIAM), is connected to graphics processor 102.
Typically, it is driven by The other components (listed above) typically pass data over a common path under the control of interrupt and arbitration schemes. The techniques and hardware required to make connections between these components are known to those skilled in the art. The operation and structure of graphics processors are described in U.S. Pat.
No. 642,625 (Tsunehiro et al.) and U.S. Patent No. 4,58
No. 0,134 (Campbell et al.), which are incorporated herein in their entirety.

In this example, the table described below is a global
Defined in memory 114.

(1) Current font storage table (CFS) 112:
Some kind of global information used by the monitoring program (executive) 122 is stored here.

(2) Font index table (FLIT) 114:
For each character in the font, it stores a pointer to the base offset, cursor increment, and specific information that describes how that character should be drawn.

(3) Character table 11B (one for each character in the 7 onts): This contains the graphic primitive 1
26 (GPCrt) and the information used by these primitives are saved.

(4) Text conversion table (TTT) 118: Information used when converting characters to be drawn is stored here (see Figure 6 for the memory map representation of the text conversion table). ).

In the global memory 108, as shown in FIG.
-time storage 120, which contains pointers used by the program, and includes a scratchpad/-
It functions as a time storage area.

The information in these tables is stored in program memory 11.
Used by two programs running from scratch. The two programs are a monitoring program 122 and a drawing program 124. The monitoring program 122 prepares the color register of the system's graphics controller 102 and sends information such as which characters and how many to draw to the CP 0100 (this is the corresponding human output device 10).
6). For each character, the monitoring program 122 calculates the address of the font index table where information about the character is stored and calls the Krg3 program 124. After searching and extracting the necessary parameters from the character table, a routine (cpcll) is called that executes the graphic primitive 126 necessary to convert the parameters and draw the character on the mapping display device fi104. It is.

In its operation, the drawing program 124 performs transformations and graphics primitives one by one until a character is drawn. The monitoring program 122 and the drawing program 124 follow in detail.

Although the term "displayed" is used in this document, it is used for convenience and does not limit the type of device on which the characters are displayed. It can be displayed on a CRT or other suitable device.

In addition, the term "r character" refers to any shape or symbol used when conveying information, such as alphanumeric characters, special characters, symbols arbitrarily selected for a particular application, etc. .

Hereinafter, the present invention will be specifically explained in more detail.

2-6 illustrate various tables used in the preferred embodiment of the invention. In this preferred embodiment, these tables are stored in random access memory (R
AM) storage area. Of course, these tables can be stored elsewhere, e.g. in read-only memory (
IIOM), a hard disk, or a floppy disk.

FIG. 2 shows the memory map of the current font storage table (CFST). This table contains global information used by drawing program 124 and monitoring program 122. Global information includes current text color 200, cursor
Position 202, cursor °Y° position 204,
The address 206 of the text conversion table (Cdingdingding), the font index table (FLtl) for the selected font
T) address 2081, number of characters in the selected font 210, etc. The current font storage table 112 is initialized before entering the monitoring program 122, and the cursor X position and cursor X position are updated as each character is displayed. Other information stored in CFST 112 may also change while each character is displayed. Although each item in the table is preferably the same size, it is possible to use items of different sizes with minor modifications to the monitoring program 122. In one example tested by the inventor, each item is 16 bits in size (this size matches the data word size of the computer being used); Of course, any word size sufficient to do so can be used.

In the current font storage table 112 shown in FIG.
It is intended that the tables of Figures 6-6 be stored in standard primary memory (ie, memory where only one address is required to address any memory location). However, the table in Figure 2 is
It can, of course, be easily modified to work with dimensional memories (ie, memories where the memory is addressed in °X° and °Y° coordinates). If tables 3 through 6 are stored in such two-dimensional memory, the entry at font index table address 208 will be FLUT'
The X' address and FLUT 'Y' address will be replaced. Similarly, items for defining the left and right boundaries of the two-dimensional memory structure are added as the start and end addresses of the character table.3 An advantage of the present invention is that similar modifications can be made. This allows data to be stored on memory devices or storage devices (eg, multi-head disks) that require any number of coordinates for data addressing. The contents of the tables of FIGS. 2-6 are independent of the type of storage device that stores the current font storage table 112.

FIG. 3 shows a memory map of the font index table 114. This font index table (F
LII'r) contains, for each character in the font, an increment of 300° 302 of the cursor °X° and °Y° position (i.e., fK, where the cursor position is updated as the character is drawn); k offset 304 (i.e.
amount that must be subtracted from the cursor °Y° position to correct the alignment of characters extending below the reference line),
The length of the character table for the selected character is 306 (i.e.
number of data items required to generate that character),
and the start address 308 of the character table. If it is necessary to draw characters using two or more methods or programs, it is also possible to create an item in FLtlT corresponding to the address 310 of the drawing program. A zero character table 116 is stored in two-dimensional memory. If so, address 308 of the character table
will consist of °X° address items and "Y° address items. As mentioned above, any number of address parameters can be modified to suit the required memory or storage device. .

Figure 4 shows the memory of the character table 40G for a single character.
It's a map. Each character table 400 contains data that identifies a graphic primitive that is desired to be executed when generating a character. It preprocesses the parameters used when a graphics primitive is executed (e.g., performs transformations and modifications using the current cursor position) and provides intermediate routines (graphics) that cause the execution of a particular graphics primitive.
Address 4 of primitive calling routine or GPCR)
This is done by providing (in the character table) 02.404.406. Each GPCR address 402.
404.406 followed by a list of parameters 40 required to cause the associated primitive to execute in the desired manner.
The last item in the 0 character table where 8 is bought is “E”
ND OF CIl8R to ACTEll'' primitive address 410.

FIG. 5 shows an example of a character table structure for the alphabetic character "B". As is clear from the figure, the alphabet “n” is -
It is possible to draw a tree using a straight line and two arcs. Therefore, the character table structure for the alphabet "B" consists of two entries 506, 508 each having the address 502 of the GPCn for the line primitive followed by the start and end parameters 504 and the address of the GPCn for the arc primitive. Continuing center point 51O1
It consists of radius 512, starting point 514, and ending point 51B information.

Of course, one character table 400 exists for each character in the font. Although these tables can be arranged consecutively in order to improve the usage efficiency of the storage device, according to the present invention, it is of course possible to operate correctly even if they are not arranged consecutively.

The advantage of using GPCRs is that the programmer can take advantage of the capabilities of any operating system or the capabilities of a particular hardware device.For example, if an operating system already has software that runs graphics primitives, If so, use GPCn to extract parameter information from the character table and apply it to existing graphics primitives.
If the software 126 is informed that it is placed in a certain location, it can find it. Thereafter, existing graphics primitive programs can be called from that software.
In embodiments, the GPCR can also be used to collect data for and call a character conversion program.

The use of GPCR also has the advantage that the present invention can be used flexibly in systems where primitive execution functions and character conversion functions are performed in hardware. In this example, the GPCR is used to extract and manipulate parameter data when needed by a certain hardware device, but if other interface functions are required, those functions can be transferred to the GPC.
For example, if the graphics processor 102 of the system is equipped with a function that can directly execute primitives, GPCII
This will serve as an interface between the two pieces of hardware. Also, in this embodiment, graphics processor 102 will draw primitives to create characters under the control of drawing program 123.

Depending on the application, it is also possible to omit the use of GPCH, read the address of the graphic primitive in the character table 115, and execute it directly.

The concept of graphic primitives is well known to those skilled in the art and is described by Donald Learn and Pauline
“Computer Graph” co-authored by Baker
cs=(Prentice-Hal1 published 1986)
and “Fundamentals of Intera” by J. D. Foley and A. Van Dam.
tive Computer-Graphics” (
Published by Addison Wesler, reprint version 19
(1983). All of these books constitute a part of this specification.

FIG. 6 shows the memory map of text conversion table 118.6 In the preferred embodiment of the present invention, 2x
A 3 or 3x3 matrix is used to convert the characters to be generated. Text conversion table 118
contains 60G of data used in this matrix. Transformation here means rotation, scaling,
The present invention, which involves adding operations such as parallel movement, uses a method also called "two-dimensional transformation using matrix multiplication." Two-dimensional transformation by matrix multiplication basically treats the X%Y coordinates of a point on a two-dimensional plane as two elements of a 3xl matrix,
How the point is transformed by multiplying its matrix by a 2x3 or 3x3 matrix. How the 0 point is translated, rotated around the origin, and scaled with respect to the origin.
Depends on the value of the 2x3 or 3x3 matrix.

The result of the matrix multiplication contains the X and Y coordinates of the transformed point. Using graphic primitives has the advantage of taking a character or string of characters in a transform by applying this technique to each primitive's parameters and then letting the primitive itself execute. The two-dimensional transformation method using matrix multiplication is well known to those skilled in the art and is described in "Pr1" co-authored by Ne*man and 5proul.
ciples of interactive Gom
puter Graphics @ (McGraw Hi
11 issue, 2nd edition printed in 1979).

This book constitutes a part of this specification. This method is explained in Chapter 4 of the same book.

The text conversion table 118 includes a monitoring program 122.
Data can be entered before entering the text and changed for each character. It is also possible to leave this table as is for a stream of several characters. Of course, the programmer can change the conversion data 600 at any time.

The operation of the character generation system and method will now be described with reference to FIGS. 1 and 7-11.

As already explained, the present invention uses a computer instruction set consisting of two parts, the monitoring program 122 and the drawing program 124. First, the operation of the monitoring program 122 is explained in FIGS. 1 and 7. Explain with reference to.

First, as shown at block 700, monitor program 1
22 is the current font storage table for fonts and colors!
12 and populates the computer's graphics processor 102's color register to set the font color. Although this step can be done elsewhere, it is preferable to do it within the monitoring program 122. Setting colors here has the advantage of allowing individual strings or characters to be set with unique colors. On monochrome systems, this information can be omitted or used to set features such as reverse video. Also, this information
If a printer or print plotter is used, it can also be used to provide color information to these devices.

Next, as shown at block 702, monitor program 1
22 can be generated by the CPU 100 (see Figure 1) to extract the number of characters in the character string to be printed and the start address of the character string (if only one character is displayed, the address of that character). , it is also possible to receive it from a corresponding input device (such as a keyboard) via the CPU 100. It is also possible to have the monitoring routine driven by an interrupt.According to the present invention, the operation is independent of where the character code is obtained.

Next, the monitoring program retrieves the first character (block 704) and determines whether the character code is recognizable as being in one of the preprogrammed fonts (block 706). In the example,
This is done by reading the number of characters in the font from the current font storage table and determining whether the font is less than or equal to that number of characters. In this operation,
It is assumed that character codes start at zero and continue up to the highest character code available for the font. If this assumption is incorrect or another method is desired, the characters can be compared to valid character codes in a character lookup table. If this is not sufficient, it is possible to create another character code table or use other known methods.

If it is recognized that the character code is not in the programmed font, the next character in the string is retrieved (blocks 708.710.704); when there are no more characters to draw, the monitoring program terminates ( block 708
, 712), the program can be easily modified to set an error flag, print an error character, or take other desired action if a character is unrecognized.

If a character code is recognized, it is stored at the offset address for the font index table (FLI).
T offset address). To do this, the program reads the base address of the appropriate font look-up table (FLtlT) from the current font storage table. If the character code read by the program is the value N, the program calculates the address of the Nth data structure from this FLUT base address. The program uses the address determined by this calculation to locate information about a given character in the font index table. Since the FLIIT base address is stored in a globally available memory area, the drawing program (or other program) can access the address from there.

In the FLIT embodiment shown in Figure 753, the data structure for each character consists of six items. Therefore, if this table were used to read the character code °02°, the base address of FLIT would need to be offset by 12 entries.

Next, as shown at block 716, the supervisor calls the drawing program 124 (described in more detail below); the supervisor sends the address of the drawing program to F.
If you want to generate a string using more than one method of extracting it from the LUT, this method has the advantage that the monitoring program can use more than one drawing program. Once finished, control is returned to the supervisory program. Once the entire string has been printed, the monitoring program terminates. If there are more characters left to print, the supervisor will pick up the next character and repeat this operation until the entire string has been processed.

The monitor program remembers the characters to print by using string pointers.

This pointer is incremented each time a character is read and compared to the expected length of the string, so it can be determined when the last character has been processed. The supervisor saves this pointer and the FLIIT offset address to the global temps store.
Since these data are stored in the computer, they can be used by the drawing program 124, other programs, routines, and hardware devices that require them.

Next, regarding the character generation operation, ': Figure 31 and Figures 8 to 1! This will be explained with reference to the figures.

As previously discussed, the system displays characters on the display device 1 by executing Limit Eve, which interfaces with the system's graphics processor 102.
04. The drawing program 124 may be thought of as having two parts; the first part of the drawing program 124 governs the execution of graphics primitives. Graphics primitives are implemented through the use of underlying subroutines (GPCRs). FIG. 9 shows a flowchart of this first part.

The second part of the drawing program consists of a collection of subroutines (graphics primitive calling routines) that call the appropriate transformation and graphics primitive routines and extract the appropriate parameters needed to perform these functions. A GPCR is provided for every primitive used to generate a font. These primitives include lines, spline curves, circles, rectangles, fills, ellipses, single pixels, end of character (END OF CII
There is an operation that caused ER). Of course, any geometric figure can be drawn as a primitive. As already mentioned, the parameters necessary for the translation and execution of primitives are contained in the translation table (FIG. 5) and the character table (FIG. 4).

As shown at block 900, the drawing program 124 first retrieves the appropriate character table address from the FLUT and saves a copy of that address in globally accessible temporary storage. This stored data is
Used as a pointer to a character table. Block 9
The program then reads the address of the first GPCH in the character table and updates the character table pointer to point to the next item, as shown at block 90.
4, jump to the GPCR address. Preferably, the GPCR is accessed as a subroutine call.

FIG. 1O is a typical GPCIt flow diagram. As shown at block 1000, the GPCR first reads parameter data from the character table and
Update pointer. As already mentioned, GPCfl
There is one for each required primitive. Each GPCR is told exactly how many parameters it needs to execute the primitive and where to put these parameters.

Next, at block 1002, the GPCR adds the cursor position to all coordinates to ensure that the drawn character is placed at the correct location (the specified location) on the screen.

Next, at block 1004, the character base offset 304 is read from the font lookup table 1114 and subtracted from the current cursor Y position so that characters extending down from the baseline line up correctly. Figure 8 makes this easier to understand.

The letter "b" is shown within cell 800 along with its reference line 802. As is clear from the figure, the letter "q" is below the reference line 802 used for the letter "b" (this reference line is normally used for most letters), Now, the current Y cursor position is at the reference line. To start the cursor from below, the base offset from the "q" data structure in FLtlT is subtracted from the current Y cursor position.

As a result, the lower edge of the alphabetic character "q" appears below the non-offset characters.

Next, at block 1006, the GPCR executes a conversion program. The conversion program retrieves the data from the text conversion table 1118. Alternatively, the GPCB can retrieve the data from the text conversion table and pass it to the conversion program. To reduce coding effort, it is desirable to have the conversion program executed as a subroutine call.

The conversion program applies conditions to the parameters of the primitive (these parameters are received from the GPCR) and stores the manipulated parameters in globally accessible storage.

Next, at block 1008, the GPCR executes the primitive program for which it is defined (preferably by a subroutine call). As mentioned above, GPCRs are located where primitive programs are expected or need to look, e.g.
Store the transformed parameters in a specific storage location in memory. As shown in FIG. 1, when primitive program 128 is executed, system graphics controller 102 draws primitives on mapping display 104. As shown in FIG. Thereafter, the first part of the drawing program is re-entered (1010) (preferably by using a return command).

The next primitive address is executed next and the cycle repeats. The last address in the character table 400 (for each character) is for the end-of-character primitive (Figure 7511).When the end-of-character primitive is executed, the cursor position is at the character FLtl.
It is updated with the X%Y increment read from entries 1 and 2 in the T structure (block 1100) and returns to the supervisor program. What is especially important is that when the end-of-character primitive is executed, the drawing program ends and the control
102 is returned to the monitoring program 122 so that the next character can be generated.

In the embodiment described above, the cursor positions stored in the current font storage table 112 are "nominal" cursor positions, which do not necessarily correspond to the positions in which each character will be displayed. This corresponds to the position at which the character will be displayed before the conversion program operates to perform any necessary translation, scaling, or rotation.

The text conversion table 1118 can be changed between the display of one character and the display of the next character. For example, each character can be changed by 10 degrees around the center point corresponding to the cursor position. If you want to rotate the character before displaying it, the rotation center retrieved from the text conversion table should be set before running the conversion program.
Can be updated using the current cursor position.

During the development of the conversion operation, rotation or scaling about a center corresponding to the center of each character can be performed. To do this, the font lookup table entry corresponding to each character is expanded to include data indicating the center position of that character relative to the initial cursor position. Therefore, before running the conversion program, the text conversion table is rotated or scaled around the character center point using the current cursor position and the character center position relative to the cursor position. It can be updated as needed.

As an alternative to the embodiments described above, it is also possible to first read one or more character tables from memory or storage and place them in global memory or temporary storage device a 120 before execution. be.

This method is used when the character table is stored in slow access memory (e.g. 2D memory) or storage (e.g. floppy) and the actual execution is performed in fast memory (e.g. static RAM). )
It may be necessary to do this from In this case, instead of putting the end-of-character address 410 at the end of the character table 400, the program remembers the number of entries in the character table, and the number of entries is the length of the character table (which is FL
Items will continue to be placed into the temporary memory ↑n device until a match is found (read from item 5 in the IIT character structure).

At that point, the program is ENDOF CIIARAC
The TER address will be inserted at the end of the character data. Once the FLIIT information is loaded into temporary storage, the program runs as described above in the first embodiment.
-Start reading information from the beginning of the time memory surface.

The present invention is not limited to drawing on the bar side. By using other primitives in conjunction with the fill primitive, it is also possible to draw characters of arbitrary width and color.6For example, to draw the letter "i", the primitive routines for rectangles and circles can be used. (i.e. you can draw a circle on top of a rectangle). r Fill”
The primitive can then be used to fill the two shapes drawn with said primitive.

This fill primitive differs from other primitives in that it actually goes into display memory, determines the outline of the polygon to be filled, and then fills the polygon with a particular color starting from a particular point. Because I'm going. Of course, it is also possible to generate two-dimensional characters using primitives that directly draw filled geometric shapes (e.g., filled rectangles and filled circles).

As understood from the above description, according to the present invention,
Rather than simply drawing or printing characters based on pre-stored bit patterns, characters can be generated in real time. It goes without saying that the various embodiments described above can be modified and improved in various ways. For example, GPCf
It is possible to omit l and have the character table contain data that directly identifies the graphics primitive program used for character generation.

Furthermore, the text conversion and base offset modification functions can be omitted if the programmer does not wish to use these functions. Additionally, the graphics primitives may be implemented in suitable hardware, firmware, or software. Therefore, it is understood that the various preferred embodiments described above are not intended to limit the invention, but are provided merely by way of example.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of the system according to the present invention, Figure 2 is a diagram showing the memory map of the current font storage table, Figure 3 is a diagram showing the memory map of the font index table, and Figure 4 is a diagram showing a single character. Figure 5 is a diagram showing an example of the character table items for the alphabet "B", Figure 6 is a diagram showing the memory map of the text conversion table, Figure 7 is a flowchart of the drawing monitoring program, and Figure 8 is a flowchart of the drawing monitoring program.
Figure 11 is a flowchart of the end-of-character routine. Figure 1θ is a flowchart of a typical graphic calling routine. ...CPU. ...Graphics processor, ...Mapping display device, ...I/O device and controller, ...Global memory, ...Program memory, 112...Current font storage. Table, +14... Font index table, 118... Character table, 118... Text conversion table, 120... -time storage area, 122... Monitoring program, 124... Drawing program, 126. ...Graphic primitives, 200...
・Current text color 202...Cursor 'X' position, 204...
Cursor °Y position, 206...Text change 1
^Table address, 208...Font index I table address, 210...Selected font, 300.302-...Car'))VX' and 'Y' increment, 304...Base offset , 306...Length of character table, 308...Start address of character table, 310...
-Address of drawing program, 400...Character table, 402.404,406...Address of intermediate routine, 408...Parameter list, 410...Address of end of character primitive, 50
2...Address of GPCn, 504...Start point and end point parameters, 505.508...Item, 510...Center point, 5!2...Radius, 514...Start point, 516... End point, 600... Conversion data, 700.702, 704, 706, 708, 710, 7
12,716,900,902.9'04.1000,
1002.1004. +006,1008,1010,
1100, 1102° 1118...Block, 800...Cell, 802...Reference line. Figure 11 Figure 10

Claims (1)

Claims: 1) means for receiving character code data identifying characters in a character set; and at least one graphic primitive in a set of different graphic primitives representing a plurality of different shapes;
By identifying the primitive, the character code
means for providing, for each received character data code, data for configuring the character identified by the data and data indicating the size and placement of the or each identified graphic primitive within the character; 2) means for generating said character from one or more graphic primitives identified by primitive identification data in the size and placement indicated by size and placement indicating data; 2. The character generating device according to claim 1, further comprising means for converting the size and arrangement data in accordance with text conversion data before the data is passed to the character generating means. 3. The character generating device according to claim 2, further comprising: means for updating the position of the cursor after the character is generated by the character generating means. 4. The character generating device according to claim 3, further comprising means for causing the character generating means to generate the character at a specific position. 5) A claim characterized in that the means for generating characters at a specific position further comprises means for modifying data indicating size and arrangement so as to instruct the means for generating characters to the specific position. The character generating device according to item 4. 6) The apparatus further comprises means for causing the character data receiving means to receive character code data of the next character after the character is generated by the character generating means. character generator. 7) means for receiving character code data identifying a character in a character set; means for reading size and alignment data for at least one graphic primitive according to said character data code; - A character generation device comprising: means for modifying according to specifications by position data; and means for generating a graphic primitive according to the modified size and arrangement data. 8) A character generating device according to claim 7, further comprising means for modifying cursor position data used by the means for modifying size and placement data. 9) A claim further comprising means for changing the cursor position data used by the means for modifying the cursor position data in response to a change in the base offset value. 8. The character generating device according to 8. 10) further comprising means for converting the modified size and placement data in accordance with text conversion data before the modified size and placement data is passed to the means for generating graphic primitives. The character generating device according to claim 7, characterized in that: 11) The character generation device according to claim 10, wherein the means for converting comprises means for converting the modified size and arrangement data according to two-dimensional conversion using matrix multiplication. 12. The character generation device according to claim 7, further comprising: means for sequentially generating graphic primitives to form a specific character. 13. The character generating device of claim 12, further comprising means for updating the current cursor position according to cursor increment data after a particular character has been generated. 14) The character generating device according to claim 7 or 10, wherein the means for modifying or the means for converting uses values stored in a table. 15) graphics processor means; mapping display means connected to said graphics processor means; program memory means; causing said graphics processor means to draw at least one predetermined shape on said mapping display means; at least one graphics primitive program for displaying a mapped representation of a character; and drawing program means residing in the program memory means for directing execution of the at least one graphics primitive program; A device for generating characters in real time using graphic primitives, characterized in that the characters are generated on the device means. 16) residing in the program memory means for receiving character code data and informing the drawing program of a starting address to cause at least one graphics primitive program to be executed in accordance with the received character code data; 16. The apparatus of claim 15, further comprising a monitoring program. 17) Furthermore, further comprising conversion means for converting at least one predetermined shape according to text conversion data,
16. Device according to claim 15, characterized in that the characters generated are displayed on the mapping display means in a rotated and/or scaled and/or translated form. 18) The apparatus of claim 17, further comprising memory means for passing text conversion data to the conversion means. 19) A computer-based method for generating and displaying characters on a visual display device using graphic primitives, the method comprising: (1) reading character code data; (2) causing the computer to execute the graphics primitives necessary to generate the characters on the bit map display. 20) The computer according to claim 19, further comprising a step (3) between steps (1) and (2) of passing to the computer a list of graphic primitives necessary for generating the character. method based on. 21) The computer-based computer according to claim 20, wherein step (3) includes the step of passing to the computer a list of starting addresses of a program that executes graphic primitives necessary to generate characters. The way I did it. 22) The computer-based method of claim 21, wherein step (3) further comprises the step of passing to the computer a list of parameters needed to execute the graphics primitive. 23) The computer-based method of claim 22, wherein passing the parameter list to the computer includes passing data indicating the size and placement of the graphics primitives. 24) passing the parameter list to the computer comprises transforming the parameters passed to the computer, such that each graphic primitive is transformed such that the character is rotated and/or translated and/or scaled; 24. The computer-based method of claim 23. 25) The computer-based method of claim 19, wherein step (2) further comprises filling at least one graphics primitive with a particular color. 26) A computer character generator using a bit map display device, characterized in that it formulates a bit map of each character to display the character. 27) means for receiving character code data identifying a character within a character set; and identifying at least one graphic primitive within a set of different graphic primitives; means for providing, for each received character data code, data for configuring and indicating the size and placement of the or each identified graphic primitive within the character; means for generating said character from one or more graphic primitives in a size and arrangement indicated by data indicative of size and arrangement; means for converting the character according to the text conversion data before being passed to the means for generating the character; means for updating the position of the cursor after the character has been generated by the means for generating the character; means for causing the generating means to generate characters at a specific position; and means for modifying data indicating size and arrangement so that the means for generating characters at a specific position instructs the character generating means to the specific position. and means for causing the character data receiving means to receive character code data of the next character after the character is generated by the character generating means, the converting means comprising: A character generation device comprising means for converting corrected size and placement data according to two-dimensional conversion using matrix multiplication. 28) means for receiving a character code identifying a character in a character set; a starting address of at least one graphic primitive routine to be executed in forming said character identified by said character code; Table memory means for storing a table containing size and arrangement data used by the routines for the character code, and storing a plurality of said graphic primitive routines from their respective starting addresses. routine memory means for operating the input character code to retrieve data representing a start address of each graphic primitive routine for the received character code from the table memory means; and a control means for executing a graphics primitive routine starting from the fetched start address, each graphics primitive routine comprising:
reading the size and placement data retrieved from the table memory means corresponding to the character code and each graphic primitive routine, and forming a graphic primitive of each shape, size and placement according to the read size and placement data; A character generation device characterized in that it can operate as follows.