CN1998024B - display device, program, and recording medium - Google Patents

Abstract

A display device of the present invention includes: the display device includes a display device that displays a line, and a control unit that controls the display device, wherein the control unit specifies a first positional relationship between at least one of a first point and a second point and a third point, with respect to the first point, the second point, and the third point, selects a line mode corresponding to the specified first positional relationship from at least one line mode prepared in advance, that is, a mode of passing at least one line of the first point and the second point, and displays the line passing through the first point and the second point on the display device in accordance with the selected line mode.

Description

Display device, program and recording medium

technical field

The present invention relates to a display device, a program, and a recording medium including a display device for displaying lines and a control unit for controlling the display device. According to the present invention, it is possible, for example, to display curved characters at a high speed on a display device having a medium or low resolution.

Background technique

Outline fonts represent text with the outline of a closed curve. The outline characters are widely used in the technology of displaying characters based on vector data. Outline characters are, for example, TrueType fonts and PostScript fonts. For the curve of the TrueType font, a quadratic B-spline curve is used (see Equation 1). Bezier curves are used for the curves of the PostScript font (see Equation 2).

[Formula 1]

x＝(1-t) ² x ₁ +2t(1-t)x ₂ +t ² x ₃

y=(1-t) ² y ₁ +2t(1-t)y ₂ +t ² y ₃

0≤t≤1

[Formula 2]

x＝(1-t) ³ x ₁ +3(1-t) ² tx ₂ +3(1-t)t ² x ₃ +t ³ x ₄

y=(1-t) ² y ₁ +3t(1-t) ² ty ₂ +3(1-t)t ² y ₃ +t ³ y ₄

0≤t≤1

These fonts are used when displaying text on high-resolution display devices. In particular, these fonts are preferably used when printing characters on paper. In addition, the curves represented by Equation 1 and Equation 2 pass through both ends of the curve (start point and end point), but do not pass through a point (control point) between the start point and end point.

Stroke fonts represent text with strokes without thickness. Similar to outline characters, this stroke font is widely used in techniques for displaying characters based on vector data.

This font is suitable for displaying text on low to medium resolution display devices. When displaying this stroke font on a display device, generally speaking, regardless of whether the line to be represented is a curve or a straight line, a plurality of points are respectively connected by a straight line to represent the curve or a straight line. than can be drawn at high speed.

Patent Document 1 discloses drawing a straight line connecting two points at high speed.

This technique finds the quotient series based on the slope of the line. Next, the control sequence is obtained from the quotient series, and a straight line is drawn at high speed based on the control sequence.

For example, calculate the quotient series {2, 1, 1, 3} according to the slope of the straight line 7/18. Next, the control sequence {1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0}. When increasing the drawing position of the straight line along the x direction, when the value of the control row and column is "1", increase the value of y to draw the straight line, and when the value of the control row and column is "0", do not increase the value of y to draw a straight line.

Patent Document 1 also discloses the content of precalculating the quotient series and the control sequence.

Patent Document 2 discloses a technique for drawing a curve at high speed. This technique precomputes and stores values associated with parametric variables, and uses these values when representing curves as Bezier curves.

For example, when the parameter t is divided into 1024 in formula 2, the values that t can obtain are (0, 1/1024, 2/1024, 3/1024, ..., 1023/1024, 1024/1024) . Here, the relationship between the value of t and the value of t ³ and the relationship between the value of t and the value of 3(1-t)t ² are calculated in advance, and these relationships are tabulated. In addition, the calculation of (1-t) ³ and 3t(1-t) ² uses the value of t ³ and the value of 3(1-t)t ² . In this way, according to the technique disclosed in Patent Document 2, the calculation represented by Equation 2 can be processed at high speed.

Patent Document 1: Japanese Unexamined Patent Publication No. 9-161082

Patent Document 2: Japanese Unexamined Patent Publication No. 1-255076

However, in the prior art, there are problems as shown below.

When outline characters are displayed on a medium-low resolution display device, line width deviation and line deformation are likely to occur, resulting in poor character quality.

In the technique of Patent Document 2, calculations involving floating-point calculations are generated every time a plurality of dots are drawn, and therefore, there is a limit to speeding up display. In general, the CPU's floating point operations are slower than the CPU's integer operations.

When a stroke font is displayed on a display device, the misalignment is particularly noticeable in the curved portion of the character. The reason for this is that stroke fonts express the curved parts of characters with straight lines. Especially when the characters are enlarged, the movement becomes conspicuous.

When expressing a curved part of a character by a quadratic B-spline curve or a Bezier curve, it is difficult to design a stroke font that has no thickness. The reason for this is that the line does not pass through the control points between the ends of the curve. As curve interpolation passing through all control points, there is curve interpolation using cubic splines. However, this interpolation needs to set restrictions on the endpoints, and there is a problem that it is difficult to attach conditions. Furthermore, there is a problem that it is difficult to increase the speed.

Contents of the invention

The present invention has been achieved in view of the above problems, and an object of the present invention is to provide a character and graphic display device, a program, and a recording medium capable of drawing lines at high speed and reducing the storage capacity of data representing the lines.

The display device of the present invention includes: a display device for displaying lines, and a control unit for controlling the display device, wherein the control unit determines the given first point, second point, and third point. The first positional relationship between the first point and at least one of the second point and the third point is based on the pattern of at least one line prepared in advance, that is, at least one of the first point and the second point In a line mode, select a line mode corresponding to the determined first positional relationship, and display a line passing through the first point and the second point to all positions according to the selected line mode. In the display device described above, a plurality of regions are allocated around the second point, the third point is assigned to one of the plurality of regions, the region assigned the third point, and the Different regions of a region have different sizes, thereby achieving the above object.

It also includes a holding unit that holds pattern information indicating the correspondence between the first positional relationship and the at least one line pattern, and the line pattern can be selected by referring to all the patterns held in the holding portion. the above mode information.

The first positional relationship may be determined according to an angle between a first straight line connecting the first point and the second point and a second straight line connecting the second point and the third point.

For the first point, the second point, and the fourth point, the control unit determines a second positional relationship between at least one of the first point and the second point and the fourth point, and the The control unit selects one line pattern corresponding to the specified second positional relationship from among the at least one line pattern, a plurality of areas are allocated around the second point, and the third point and the A fourth point is assigned to the same area of the plurality of areas, a line pattern corresponding to the determined first positional relationship, and a line pattern corresponding to the determined second positional relationship It can also be the same.

The first point may be assigned to the origin and the second point to the first quadrant.

A plurality of areas are allocated around the second point, and the third point is assigned to one of the plurality of areas, one of the plurality of areas, and an area different from the one area. , with different sizes.

A plurality of areas are assigned to only a portion around the second point, and the third point may be assigned to one of the plurality of areas.

The program of the present invention is used to cause an information display device equipped with a display device for displaying lines to execute display processing including determining the first point, the second point, and the third point assigned to the first point, the second point, and the third point. point and at least one of the second point and the first positional relationship between the third point; from the pattern of at least one line prepared in advance, that is, passing through at least one of the first point and the second point In a line mode, the step of selecting a line mode corresponding to the determined first positional relationship; and according to the selected line mode, passing through the first point and the second point The lines shown in the steps to the display device, whereby the above object can be achieved.

The recording medium of the present invention can be read by an information display device equipped with a display device for displaying lines, and the recording medium records a program for causing the information display device to perform display processing. The display processing includes: The first point, the second point and the third point of the first point, the step of determining the first positional relationship between at least one of the first point and the second point and the third point; from at least one pre-prepared line In the mode of at least one line that passes through the first point and the second point, the step of selecting a line mode corresponding to the determined first positional relationship; and according to the mode of the selected line , a step of displaying a line passing through the first point and the second point on the display device, a plurality of regions are allocated around the second point, and the third point is assigned to the plurality of regions. One of the regions, one of the plurality of regions, and a region different from the one region have different sizes, thereby achieving the above object.

(invention effect)

According to the display device, program, and recording medium of the present invention, it is possible not to obtain the locus of the line passing through the first point and the second point based on calculation, but to obtain the locus of the line passing through the first point and the second point from at least one pattern of the line passing through the first point and the second point. , select a line mode corresponding to the determined positional relationship, so that a line passing through the first point and the second point can be displayed. Therefore, it is not necessary to calculate the locus of the line passing through the first point and the second point through complicated calculations, and the line passing through the first point and the second point can be displayed at high speed.

In the present invention, a curve connecting the three points is drawn using a table showing the correspondence between the pattern of the line passing through the first point and the second point and the positional relationship of the three points. Therefore, drawing of a curve can be realized only by reading a table, and no complicated calculation is performed. As a result, a line passing through the first point and the second point can be drawn at high speed.

Furthermore, the angles of the straight line passing through the first point and the second point and the straight line passing through the second point and the third point are classified and tabulated. As a result, capacity can be reduced.

And only when the second point is located in the first quadrant, angle classification and tabulation of a straight line passing through the first point and the second point and a straight line passing through the second point and the third point are performed. Therefore, combinations of three-point positions can be reduced. As a result, the capacity can be further reduced.

Description of drawings

FIG. 1 is a diagram showing an example of a curve passing through three points.

Fig. 2 is a diagram showing another example of a curve passing through three points.

Fig. 3 is a diagram showing still another example of a curve passing through three points.

Fig. 4 is a diagram showing still another example of a curve passing through three points.

Fig. 5 is a diagram showing still another example of a curve passing through three points.

Fig. 6 is a diagram showing still another example of a curve passing through three points.

FIG. 7 is a diagram showing areas 1 to 28 allocated around the second point.

FIG. 8 is a diagram showing the structure of the character display device 100 according to the embodiment of the present invention.

FIG. 9 is a diagram showing an example of character data 42 .

FIG. 10 is a diagram showing an example of display of character data 42 .

FIG. 11 is a diagram showing an example of the straight line table 43 .

FIG. 12 is a diagram showing an example of the curve table 44 .

Fig. 13 is a diagram showing the values contained in the control column.

Fig. 14 is a flowchart showing the procedure of character display processing.

FIG. 15 is a flowchart showing the procedure of the rendering data conversion process executed in step S104.

FIG. 16 is a flowchart showing the procedure of the line drawing process executed in step S203.

FIG. 17 is a flowchart showing the procedure of the curve drawing process executed in step S204.

FIG. 18 is a flowchart showing the procedure of the first quadrant drawing process executed in step S409.

FIG. 19 is a flowchart showing the procedure of the second quadrant drawing process executed in step S410.

FIG. 20 is a flowchart showing the procedure of the third quadrant drawing process executed in step S411.

FIG. 21 is a flowchart showing the procedure of drawing the fourth quadrant executed in step S412.

FIG. 22 is a diagram showing coordinate data, scaled data, and quantized data.

FIG. 23 is a graph showing the results of rendering based on the quantized data shown in FIG. 22 .

Fig. 24 is a flowchart showing the table editing processing procedure.

FIG. 25 is a diagram showing a pattern of lines after display points have been changed.

FIG. 26 is a diagram showing a graph drawing table after display points are changed.

Fig. 27 is a diagram showing the correspondence between the value of tan ^-1 and the argument of tan ^-1 .

FIG. 28 is a diagram showing an example of areas allocated around the second point.

In the figure: 10-input device, 20-control unit, 21-CPU, 22-main memory, 30-display device, 40-auxiliary storage device, 41-text display program, 42-text data, 43-linear form, 44 - curve table, 100 - text display device 1 .

Detailed ways

1. Principle of the present invention

The principle of the present invention will be described below with reference to the accompanying drawings.

When the present invention draws a curve, it focuses on the curve connecting three points, and selects a line mode corresponding to the determined positional relationship from at least one line mode passing through the first point and the second point, so that it can be displayed through The line between the first point and the second point. By selecting the mode of the line passing through the first point and the second point without calculating the locus of the line passing through the first point and the second point, the line passing through the first point and the second point can be displayed at high speed.

Furthermore, a holding unit is provided for holding pattern information indicating a correspondence relationship between a positional relationship and a line pattern, and the selection of the line pattern is performed by referring to the pattern information held in the holding portion. The mode information is expressed in a table, and the curve is drawn based on the table.

The reason why the pattern information is represented by tables and the curves are drawn based on these tables is as follows.

Set the first point as the origin (0, 0). Set the second point to be within ±d from the first point in the x-direction and y-direction. The third point is set to increase or decrease within ±d from the second point in the x-direction and y-direction.

In this case, the combination of the first point and the second point is (2d+1)×(2d+1). The combination of the second point and the third point is also (2d+1)×(2d+1). Therefore, the combination of three points is (2d+1) ⁴ . In this way, the combination of positions of the three points increases sharply according to d. For example, in the case of d=5, it is 14,641; in the case of d=10, it is 194481; in the case of d=20, it is 2825761. Since there is a limit to the data capacity that a character display device can store, when there are many combinations of three o'clock positions, it is difficult to represent these combinations in a table and store these tables in the character display device.

As described above, the present invention focuses on the fact that the first and second points of the first curve are different from the first and second points of the second curve even in the case of representing two different curves (first curve, second curve). The same is true for two points, the angle between the straight line passing through the first point and the second point of the first curve and the straight line passing through the second point and the third point of the first curve, and the angle between the first point and the second point passing through the second curve When the angle between the straight line of the point and the straight line passing through the second point and the third point of the second curve is closer than the specified value, even if the pattern of the line passing through the first point and the second point is the same pattern, the first curve is observed People with the second curve will not feel different.

Figure 1 shows an example of a curve passing through three points.

The curve passes through the first point (0,0), the second point (7,4), and the third point (10,10). In Figure 1, the blackened points are these three points, the points with more hatching are the points contained in the line passing through the first point and the second point, and the points with less hatching are the points passing through the second point and the third point The points contained in the line. Also, a straight line passing through the first point and the second point, and a straight line passing through the second point and the third point are shown.

Figure 2 shows another example of a curve passing through three points.

The curve passes through the first point (0,0), the second point (7,4), and the third point (13,16). The first point (0, 0) and the second point (7, 4) are the same as the first point and the second point in Figure 1, and the third point (13, 16) is through the second point and the third point in Figure 1 The point on the extension of the line of the point.

Comparing the patterns of the lines of FIG. 1 with those of FIG. 2, the patterns of the lines passing through the second and third points are different, while the patterns of the lines passing through the first and second points are the same.

Fig. 3 shows yet another example of a curve passing through three points.

The curve passes through the first point (0,0), the second point (7,4), and the third point (12,17). The first point (0, 0) and the second point (7, 4) are the same as the first point and the second point in FIG. 2 , and the third point (12, 17) is the upper left point of the third point in FIG. 2 . The angle between the straight line passing through the first point and the second point and the straight line passing through the second point and the third point in Figure 2, and the straight line passing through the first point and the second point in Figure 3 and the second point and the third point The angle of the straight line is close.

Comparing the patterns of the lines of FIG. 2 with those of FIG. 3, the patterns of the lines passing through the second and third points are different, while the patterns of the lines passing through the first and second points are the same.

Fig. 4 shows another example of a curve passing through three points.

The curve passes through the first point (0,0), the second point (7,4), and the third point (14,16). The first point (0, 0) and the second point (7, 4) are the same as the first point and the second point in Figure 2, and the third point (14, 16) is the lower right point of the third point in Figure 2 .

Comparing the patterns of the lines of FIG. 2 with those of FIG. 4, the patterns of the lines passing through the second and third points are different, while the patterns of the lines passing through the first and second points are the same.

As described with reference to FIGS. 1 to 4 , when different curves are drawn, even if the patterns of the lines passing through the first point and the second point are made the same, people who observe the curves do not feel the difference.

Fig. 5 shows yet another example of a curve passing through three points. The curve passes through the first point (0,0), the second point (7,4), and the third point (5,12).

Fig. 6 shows yet another example of a curve passing through three points. The curve passes through the first point (0,0), the second point (7,4), and the third point (14,6).

The first point (0, 0) and the second point (7, 4) shown in Fig. 5 and Fig. 6 are the same as the first point and the second point shown in Fig. 1 to Fig. 4, but through the first point and the The angle between the straight line at two points and the straight line passing through the second point and the third point is very different from the angles shown in Fig. 4 different.

FIG. 7 shows the regions 1 to 28 allocated around the second point.

Area 1 to area 28 are assigned by dividing the area around the second point into 28 equal parts. When the third point is in the same area, the pattern of the line passing through the first point and the second point is made the same, thereby reducing the combination of three points. For example, when the third point in the first curve is located at position A in area 1, and the third point is located at position B in area 1 different from position A in the second curve, make the first curve pass through the first point and The pattern of the line of the second point is the same as the pattern of the line of the second curve through the first point and the second point.

When areas 1 to 28 are assigned around the second point, and the first point is (0, 0) and the second point is (X, Y) (X≤±d, Y≤±d: along the x direction and When the distance from the first point in the y direction increases or decreases within ±d), the position of the third point is located in any one of areas 1 to 28. Therefore, the combination of three points is (2d+1) ² ×28.

And, only when the second point is located in the first quadrant, a table representing the correspondence between the positional relationship and the pattern of the line is generated, and when the second point is located in a quadrant other than the first quadrant, the positional relationship is obtained using the table Correspondence with the pattern of the line, thereby reducing the number of tables.

Only when the second point is in the first quadrant, the angle between the line passing through the first point and the second point and the line passing through the second point and the third point, and the angle between the line passing through the first point and the second point are represented by the table The correspondence between the modes of the curves. Consider symmetry with respect to the y-axis if the second point is in the second quadrant, consider symmetry with respect to the origin if the second point is in the third quadrant, and consider symmetry with respect to the origin if the second point is in the fourth quadrant Consider symmetry about the x-axis. In this case, the combination of three points is (d+1) ² ×28. For example, when d=5, the number of combinations is 1008, when d=10, the number of combinations is 3388, and when d=20, the number of combinations is 12348, and the capacity necessary for storing tables representing these combinations can be reduced.

In addition, the area allocated around the second point is not limited to 28 divisions. The number of divisions is arbitrary. If the number of divisions is increased, the capacity of the table is also increased, but the quality of the curve can be improved. Moreover, it is not limited to equal division. It is also possible to finely segment where the angle is shallow and roughly segment where the angle is deep.

Fig. 28 shows an example of the area allocated around the second point.

Fig. 28(a) shows a plurality of regions of different sizes (division method 1).

A plurality of areas 1 to 8 are allocated around the second point. The third point is assigned to area 2. For example, area 1 is not the same size as area 4.

Fig. 28(b) shows a region allocated only to a part of the second point (division method 2).

A plurality of areas 1 to 5 are allocated around the second point. However, other parts (hatched parts) have no assigned area.

The division method around the second point can be selected according to the display object. For example, in the case of displaying Chinese characters, select division method 1. When displaying katakana, select split method 2. In addition, "display object" means an object displayed on a display device. For example, characters (kanji, hiragana, katakana, Latin alphabet, etc.), graphics, symbols.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

2. Text display device

FIG. 8 shows a character display device 100 according to an embodiment of the present invention.

The character display device 100 may be, for example, a personal computer. Any type of computer such as desktop, laptop, etc. may be used as the personal computer. Alternatively, the text display device may also be a word processor.

Furthermore, the character display device may be any information display terminal such as electronic equipment and information equipment equipped with a display device. For example, the character display device may be an electronic device equipped with a liquid crystal display device, a portable information terminal as a form information tool, a mobile phone including a PHS, or a general communication device such as a telephone/FAX.

The character display device 100 includes an input device 10 , a display device 30 for displaying lines, a control unit 20 for controlling the display device 30 , and an auxiliary storage device 40 .

The input device 10 is used to input information indicating characters to be displayed on the display device 30 to the control unit 20 . The information representing characters includes, for example, codes for identifying characters and size information representing the size of characters.

Any type of input device capable of inputting codes and sizes can be used as the input device 10 . Input devices such as keyboard, mouse or pen input device can be used. When the character display device 100 is a mobile phone, the code or size may be input using the numeric keys for specifying the telephone number of the communication destination. When the character display device 100 has a mechanism for connecting to a communication line including the Internet, a message included in an e-mail received through the communication line may be displayed on the display device 30 . In this case, the means for connecting to the communication line functions as the input device 10 .

The auxiliary storage device 40 stores a character display program 41 , character data 42 necessary for executing the program, a straight line table 43 , and a curve table 44 .

The character display program 41 includes: a scaling program 41a that scales the character data 42 according to the size output to the display device, a quantization program 41b that quantizes the zoomed result, and converts the quantized result into drawing data to make the quantization The converted result can be displayed on the rendering data conversion program 41c of the display device.

As the auxiliary storage device 40, any type of auxiliary storage device capable of storing the character display program 41, character data 42, straight line table 43, and curve table 44 can be used. In the auxiliary storage device 40 , any recording medium can be used as a storage medium for storing the character display program 41 , character data 42 , straight line table 43 , and curve table 44 . For example, hard disks, CD-ROMs, CD-Rs, MOs, DVDs, and IC cards are preferably used.

In addition, the character display program 41 , the character data 42 , the straight line table 43 and the curve table 44 are not limited to be stored in the recording medium included in the auxiliary storage device 40 . For example, the character display program 41, character data 42, straight line table 43, and curve table 44 may be stored in the main memory 22, or may be stored in a ROM (not shown). The ROM includes, for example, mask ROM, EPROM, EEPROM, and flash ROM. When these data are stored in the ROM, various processing changes can be easily realized only by exchanging the ROM. For example, when the character display device is a portable information terminal or a mobile phone, it is preferable to use a ROM.

Furthermore, the character display program 41, character data 42, straight line table 43, and curve table 44 are stored in a storage medium that permanently holds programs and data, such as a storage device such as a disk or a card, or a semiconductor memory. When the character display device has a mechanism for connecting to a communication line including the Internet, at least part of the character display program 41, character data 42, straight line table 43, and curve table 44 can be downloaded from the communication line. In this case, the loading program required for downloading may be stored in a ROM (not shown) in advance, or may be installed into the control unit 20 from the auxiliary storage device 40 .

The control unit 20 includes a CPU 21 and a main memory 22 .

The CPU 21 controls and monitors the entire character display device, and executes a character display program 41 stored in the auxiliary storage device 40 .

The main memory 22 temporarily stores data input from the input device 10 , data to be displayed on the output device 30 , and data required for executing the character display program 41 . The main memory 22 is controlled by the CPU 21 .

The CPU 21 executes the character display program 41 based on various data stored in the main memory 22 to generate drawing data. The generated drawing data is temporarily stored in the main memory 22 and then output to the display device 30 . The timing at which the rendering data is output to the display device 30 is controlled by the CPU 21 .

An example of character data 42 is shown in FIG. 9 . Specifically, the character data shown in FIG. 9 is vector data of the character "big" and has a resolution of 256 meshes. The character data shown in FIG. 9 includes a plurality of coordinate data.

The line No is a number assigned to the lines constituting the character "big". X represents the X coordinate value of a point on the line constituting the character "big". Y represents the Y coordinate value of a point on the line constituting the character "big".

The text "big" is formed by three lines. Each of the three lines has a plurality of coordinate data representing positions. Line No1 connects (8, 184) and (247, 184), and line No2 connects (127, 246), (127, 181), (103, 106), (61, 49) and (11, 14) These five points are connected by line No3 (127, 181), (144, 127), (176, 73), (208, 40) and (246, 14).

FIG. 10 shows an example of display of character data 42 . Specifically, it is the display of the character data shown in FIG. 9 .

An example of the line table 43 is shown in FIG. 11 . The straight line table 43 is stored in the auxiliary storage device 40 (see FIG. 8 ).

"index" represents the record number of the table, and "(dx, dy)" represents the increment in x direction and the increment in y direction from the first point.

In this embodiment, the increase in the x direction and the increase in the y direction are within 20, but the increase in the x direction and the increase in the y direction are not limited to within 20. The increase in the x direction as well as the increase in the y direction is arbitrary.

The "control column" is represented by "0" and "1". When dx≥dy, in the case of increasing 1 in the x direction, the increment of y is represented by "0" and "1". "0" indicates that the increase in the y direction is 0 when 1 is added along the x direction; "1" indicates that the increase in the y direction is 1 when 1 is added along the x direction.

For example, in the case of (dx, dy)=(2, 1), the control column is {0, 1}. In the case of an increase of 1 in the x direction from the first point, the control column {0, 1} indicates that the increase in the y direction is 0, and when the next increase in the x direction is 1, the increase in the y direction is 1 . Indicates the pattern of the line passing through the first and second points, according to the pattern of the line represented by this control column.

An example of the curve table 44 is shown in FIG. 12 . The curve table 44 is stored in the auxiliary storage device 40 (see FIG. 8 ).

Figure 13 shows the values that the control column has.

"index" represents the record number of the table, and "(dx, dy)" represents the increment in the x direction and the increment in the y direction from the first point.

In this embodiment, the increase in the x direction and the increase in the y direction are within 15, but the increase in the x direction and the increase in the y direction are not limited to within 15. The increase in the x direction as well as the increase in the y direction is arbitrary. The range of the increase in the x direction and the increase in the y direction of the curve form is smaller than that of the straight line form in the x direction and the increase range in the y direction. The reason is that the distance between two points of the curve of the general character is smaller than that of the character. The distance between two points of a line.

"Angle" indicates which of the areas 1 to 28 the third point is located in (see FIG. 7 ).

The "control column" is represented by "0" to "7" (see FIG. 13 ). "0" means move right relative to the second point, "1" means move up right, "2" means move up, "3" means move up left, "4" means move left, "5" means move down left Move, "6" means move down, "7" means move down to the right. For example, when (dx, dy)=(7, 4) and the third point is located in area 2, the control sequence is {0, 0, 1, 0, 1, 1, 1} (see FIG. 12 ). The control column indicates that the movement from the first point is right, right, upper right, right, upper right, upper right, upper right. The pattern of the line expressed based on this movement, when the three points are the first point (0, 0), the second point (7, 4), and the third point (10, 10), indicates that the line passing through the first point and The pattern of the line at the second point (see Figure 1).

As described with reference to FIG. 12 , the information included in the curve table 44 indicates the correspondence relationship between the positional relationship between the second point and the third point and the pattern of the line. This curve table 44 is prepared in advance in the auxiliary storage device 40 .

In addition, the pattern of the line displayed based on the "control column" contained in the curve table 44 is not limited to a curve. The pattern of lines represented by "control columns" may be straight lines. Such a control column is for example {1, 1, 1, 1}.

The character display device 100 according to the embodiment of the present invention has been described above with reference to FIGS. 1 to 13 and 28 .

For example, in the examples in FIGS. 1 to 13 and FIG. 28 , the display device 30 corresponds to a “display device that displays lines”; the control unit 20 corresponds to a “control unit that The first point, the second point, and the third point, the control unit that determines the first positional relationship between at least one of the first point and the second point and the third point", "on at least one line prepared in advance In the pattern, that is, from the pattern of at least one line passing through the first point and the second point, select a line pattern corresponding to the determined first position relationship" and "according to the pattern of the selected line , and display the line passing through the first point and the second point on the control unit of the display device". Furthermore, the auxiliary storage device 40 storing the straight line table 42 and the curve table 44 corresponds to "a holding unit for holding pattern information indicating a correspondence relationship between the first positional relationship and the line pattern".

However, the embodiments shown in FIGS. 1 to 13 and FIG. 28 are merely examples of the functions of the character display device of the present invention. As long as the functions of the above-mentioned mechanisms can be achieved, any character display device with any structure is included in the scope of the present invention.

For example, the linear table 42 and the curved table 44 can be input to the display device from outside the display device. For example, when the straight line table 42 and the curved line table 44 are stored in a holding unit connected to the display device via a network, the straight line table 42 and the curved line table 44 can be input to the display device from outside the display device.

For example, each mechanism mentioned above may be realized by hardware, may also be realized by software, and may also be realized by hardware and software.

For example, a program for executing a character display processing procedure (hereinafter referred to as a character display processing program) is stored in the character display device. The text display processing program can be pre-stored in the program storage mechanism included in the text display device when the computer leaves the factory.

Alternatively, the character display processing program may be stored in the program storage means after the computer is shipped from the factory. For example, a user can download a text display processing program for a fee or free of charge from a specific website on the Internet, and install the downloaded program into the computer. When the character display processing program is stored in a computer-readable storage medium such as a floppy disk, CD-ROM, DVD-ROM, etc., the character display processing program can be installed in the computer using an input device (for example, a disk drive). The installed program is stored in the program storage means.

Note that details of the character display processing procedure will be described later.

As described with reference to FIGS. 1 to 13 and FIG. 28 , according to the display device of the present invention, the locus of the line passing through the first point and the second point can not be obtained by calculation, but can be obtained from the first point and the second point. In the mode of at least one line of two points, a mode of one line corresponding to the identified positional relationship is selected so that a line passing through the first point and the second point can be displayed. Therefore, it is possible to display the line passing through the first point and the second point at high speed without requiring complicated calculations to calculate the locus of the line passing through the first point and the second point.

In the present invention, a curve connecting the three points is drawn using a table showing the correspondence between the pattern of the line passing through the first point and the second point and the positional relationship of the three points. Therefore, it is possible to draw a curve only by reading out a table without complicated calculations. As a result, a line passing through the first point and the second point can be drawn at high speed.

In addition, the angles of the straight line passing through the first point and the second point and the straight line passing through the second point and the third point are classified to form a table. As a result, capacity can be reduced.

Furthermore, only when the second point is located in the first quadrant, angle classification and tabulation of a straight line passing through the first point and the second point and a straight line passing through the second point and the third point are performed. Therefore, combinations of three-point positions can be reduced. As a result, the capacity can be further reduced.

3. Display method

Fig. 14 shows the character display processing procedure. Character display processing is performed by CPU 121 executing character display program 141 .

Next, the character display processing procedure will be described step by step with reference to FIGS. 8 and 14 .

Step S101: According to the instruction input from the input device 10, read the character data representing the designated character from the character data 42. For example, the character data to be read includes a plurality of coordinate data (see FIG. 9 ).

Step S102: The coordinate data included in the read text data is scaled to fit the output size. When the output size is n dots, the coordinate data (x, y) is scaled based on a predetermined calculation, and changed into scaled data (X, Y). The prescribed calculations refer to X=(n-1)×x/255 and Y=(n-1)×y/255.

For example, when the output size is 36 dots, the coordinate data (x, y) (see FIG. 9 ) is scaled based on predetermined calculations and changed to scaled data (see FIG. 22 ).

Step S103: The scaled data is quantized and changed into quantized data. For example, there is rounding as a method of quantization. For example, coordinate data (x, y) (see FIG. 9 ) is scaled based on predetermined calculations, and then quantized to be changed into quantized data (see FIG. 22 ).

In addition, the method of performing quantization is not limited to rounding. Another method of quantization is disclosed in the same application as the present application (Japanese Patent Application No. 2003-137918). Among the disclosed methods are methods for suppressing quantization errors.

Step S104: Refer to the straight line table 43 and the curve table 44, and obtain drawing data from the quantized data.

Step S105: Display the image on the display device 30 according to the rendering data.

After the image is displayed on the display device 30, the process ends.

FIG. 15 shows the procedure of rendering data conversion performed in step S104.

Next, the drawing data conversion process procedure will be described step by step with reference to FIG. 15 .

Step S201: Take out quantized data. For example, in the case of the character "big", quantized data corresponding to the found line No is taken out (see FIG. 22 ). First, the line No. 1 is found, and the corresponding quantized data ((1, 25), (34, 25)) are taken out. Next, line No. 2 is found, and the corresponding quantized data ((17, 34), (17, 25), (14, 15), (8, 7), (2, 2)) are taken out. Finally, line No.3 is found, and the corresponding quantized data ((17, 25), (20, 17), (24, 10), (29, 5), (34, 2)) are taken out.

Step S202: Determine whether the quantized data corresponding to the found line No contains more than three coordinate points.

When it is determined that three or more coordinate points are included (Yes), the process proceeds to step S204. When it is determined that three or more coordinate points are not included (No), the process proceeds to step S203.

Step S203: Obtain drawing data so that the line represented by the found line No is drawn as a straight line. Drawing data is obtained from the quantized data with reference to the straight line table 43 .

Step S204: Obtain drawing data such that the line represented by the found line No is drawn in a curved line. Referring to the graph table 44, drawing data is obtained from the quantized data.

Step S205: Determine whether there is a line to be found.

When it is determined that there is a line to be found (Yes), the process proceeds to step S201. When it is determined that there is no line to be found (No), the process ends.

FIG. 16 shows the procedure of the line drawing process executed in step S203.

Next, the line drawing processing procedure will be described step by step with reference to FIG. 16 .

Step S301: Obtain the next values of the coordinate points (x ₁ , y ₁ ) and (x ₂ , y ₂ ) of the assigned two points. Calculate the distance dx between x ₁ and x ₂ according to dx←abs(x ₂ -x ₁ ), and calculate the distance dy between y 1 and _{y 2} according to dy←abs(y ₂ -y ₁ ).

In addition, the function abs(t) represents the absolute value of t.

Also, when the variable representing the drawing position is represented by (x, y), x←x ₁ and y←y ₁ represent processing for setting the first point at the drawing start position.

Step S302: Turn the first point (x, y) into data.

Step S303 : Get the control column from the straight line table 43 . Access to the line table is performed by the following calculations.

If the range of the table is set to n, the control column of the number ((n+1)×dy+dx+1) in the straight line table 43 is acquired. In this embodiment, since the range of the table is set to 20, a control column of ((20+1)×dy+dx+1) is acquired.

Step S304: Determine which of x ₁ and x ₂ is larger.

When it is determined that _x2 is equal to or greater than _x1 (Yes), the process proceeds to step S305. When it is determined that _x2 is smaller than _x1 (NO), the process proceeds to step S306.

Step S305: Set the variable incx to the value "1". Controls the increase or decrease along the x direction based on the variable incx.

Step S306: Set the variable incx to the value "-1". Controls the increase or decrease along the x direction based on the variable incx.

Step S307: Determine which of y ₁ and y ₂ is larger.

When it is determined that _y2 is equal to or greater than _y1 (Yes), the process proceeds to step S308. When it is determined that y ₂ is smaller than y ₁ (No), the process proceeds to step S309.

Step S308: Set the variable incy to the value "1". Controls the increase or decrease along the y direction based on the variable incy.

Step S309: Set the variable incy to the value "-1". Controls the increase or decrease along the y direction based on the variable incy.

Step S310: Determine which of dx and dy is larger.

When it is determined that dx is equal to or greater than dy (Yes), the process proceeds to step S311. When it is determined that dx is smaller than dy (No), the process proceeds to step S314.

Step S311: Determine whether the control sequence ends. When it is judged that the control sequence is ended (Yes), the processing is ended. When it is determined that the control sequence has not ended (NO), the process proceeds to step S312.

Step S312: Calculate the next point of (x, y). Specifically, the value of incx that controls the increase or decrease of x is added to x (the next value of x = x + incx), and the value of incy that controls the increase or decrease of y is multiplied by the value of the control column (Δy) to y ( Next value of y=y+incy×Δy).

Step S313: convert (x+incx) and (y+incy×Δy) into rendering data. Specifically, the point (x+incx, y+incy×Δy) is plotted. Then, the process proceeds to step S311.

Step S314: Determine whether the control sequence ends. When it is judged that the control sequence ends (YES), the process ends. When it is determined that the control sequence has not ended (NO), the process proceeds to step S315.

Step S315: Calculate the next point of (x, y). Specifically, add to x the value of incx that controls the increase or decrease of x multiplied by the value of the control column (Δx) (the next value of x = x+incx×Δx), and add to y the value that controls the increase or decrease of y The value of incy (next value of y = y+incy).

Step S316: convert (x+incx×Δx) and (y+incy) into drawing data. Specifically, the point (x+incx×Δx, y+incy) is plotted. Then, the process proceeds to step S314.

FIG. 17 shows the steps of the curve drawing process executed in step S204.

Next, the curve drawing processing procedure will be described step by step with reference to FIG. 17 .

Step S401: Take out three points from the assigned coordinate points. For example, the assigned coordinate points are ((a ₁ , b ₁ ), (a ₂ , b ₂ ), (a ₃ , b ₃ ), (a ₄ , b ₄ ), (a ₅ , b ₅ )) In the case of these five points, three points (a ₁ , b ₁ ), (a ₂ , b ₂ ), (a 3 , b 3 ) are taken out in the first search, and (a ₃ , b ₃ ) are taken out in the next search. a ₂ , b ₂ ), (a ₃ , b ₃ ), (a ₄ , b ₄ ). While staggering a little, take out such consecutive three points.

Step S402: Calculate the next value of the extracted three coordinate points (x ₁ , y ₁ ), (x ₂ , y ₂ ), (x ₃ , y ₃ ). Calculate the distance dx between x1 and x2 based on dx←abs(x ₂ -x ₁ ), and calculate the distance dy between y ₁ and y ₂ based on dy←abs(y ₂ -y ₁ ).

In addition, when the variable indicating the drawing position is represented by (x, y), x← _x1 and y← _y1 represent the processing of setting the first point at the drawing start position in the third point.

Step S403: Convert the first point (x, y) into rendering data within the three extracted points.

Step S404: Calculate the angle pattern according to the angle between the straight line passing through the first point and the second point and the straight line passing through the second point and the third point.

The angle pattern can be calculated as a=round(((Θ ₂ -Θ ₁ )×28)/(2×Π)).

Here, the angle Θ ₁ is the angle between the line passing through the first point and the second point and the x-axis (Θ ₁ =tan ^-1 ((y ₂ -y ₁ )/(x ₂ -x ₁ ))), the angle Θ ₂ is the angle between the line passing through the second point and the third point and the x-axis (Θ ₂ =tan ⁻¹ ((y ₃ −y ₂ )/(x ₃ −x ₂ ))).

The function round(t) represents the rounding of t. The calculation of tan ^-1 makes the processing complicated, but in the case of the present invention, as long as it finally meets any angle pattern divided by 28, the requirement for accuracy is not high. Therefore, the calculation of tan ^-1 can also be accelerated by using a table that classifies the parameters of tan ^-1 into arbitrary patterns.

In addition, the method of speeding up the calculation of tan ^-1 by using a table showing the correspondence relationship between the parameter of tan-1 and the value of tan ^{- 1} will be described later in detail.

As described above with reference to steps S401 to S404, by executing steps S401 to S404, at least one of the first point and the second point can be specified for the given first point, second point, and third point. The positional relationship with the third point.

Step S405 : Get (select) the control column from the curve table 44 . Access to the curve table is performed by the following calculation.

If the range of the table is set to n, the number of divisions is set to t, and the angle mode is set to a, then the control of No. ((n+1)×t×dy+t×dx+a) in the curve table 44 is obtained List. In this embodiment, since the range of the table is set to 15 and the number of divisions is set to 28, the ((15+1)×28×dy+28×dx+a)-th control column is obtained.

As described with reference to step S405, by executing step S405, the curve table 44 that contains information representing the correspondence between the positional relationship between the second point and the third point and the pattern of the line can be selected to represent the pattern of the desired line. control column.

Step S406: Determine which of x ₁ and x ₂ is larger.

When it is determined that _x2 is equal to or greater than _x1 (Yes), the process proceeds to step S407. When it is determined that x ₂ is smaller than x ₁ (NO), the process proceeds to step S408.

Step S407: Determine which of y ₁ and y ₂ is larger.

When it is determined that _y2 is equal to or greater than _y1 (Yes), the process proceeds to step S409. When it is determined that y ₂ is smaller than y ₁ (No), the process proceeds to step S410.

Step S408: Determine which of y ₁ and y ₂ is larger.

When it is determined that y ₂ is equal to or greater than y ₁ (Yes), the process proceeds to step S411. When it is determined that y ₂ is smaller than y ₁ (No), the process proceeds to step S412.

Step S409: When the first point is set as the origin, draw the first quadrant when the second point is located in the first quadrant.

Step S410: When the first point is set as the origin, draw the second quadrant when the second point is located in the second quadrant.

Step S411 : When the first point is set as the origin, draw the third quadrant when the second point is located in the third quadrant.

Step S412: When the first point is set as the origin, draw the fourth quadrant when the second point is located in the fourth quadrant.

Step S413: Determine whether the identifier is set. When it is judged that the identifier is set (Yes), the process ends. When it is determined that the identifier is not set (NO), the process proceeds to step S414.

Step S414: Determine whether the three points obtained by executing step S401 are the last three points.

For example, the coordinate points given to the curve drawing process are (a ₁ , b ₁ ), (a ₂ , b ₂ ), (a ₃ , b ₃ ), (a ₄ , b ₄ ), (a ₅ , b ₅ ) In the case of these five points, it is determined whether the three points extracted in step S401 are the last three points (a ₃ , b ₃ ), (a ₄ , b ₄ ), (a ₅ , b ₅ ).

When it is determined to be the last three points (Yes), the process proceeds to step S415. When it is determined that it is not the last three points (NO), the process proceeds to step S401.

Step S415: Set the identifier, and set three points on the contrary.

For example, in the case of setting the last three points in the order of (a ₃ , b ₃ ), (a ₄ , b ₄ ), (a ₅ , b ₅ ), in the order of (a ₅ , b ₅ ), (a ₄ , b ₄ ), (a ₃ , b ₃ ) order to change the last three points. Its purpose is to prevent (a ₄ , b ₄ ) and (a ₅ , b ₅ ) from being delineated.

When three points are sequentially taken out for processing (refer to step S401), what is drawn is between the first point and the second point within the three points, and the area between the second point and the third point is not drawn. In order to prevent the final interval ((a ₄ , b ₄ ) and (a ₅ , b ₅ )) from being drawn, finally swap point (a ₃ , b ₃ ) and point (a ₅ , b ₅ ), for the final range is depicted.

In addition, in this embodiment, the last three points are reversed, but the "processing of step S414" may be changed to "processing of determining whether or not the acquired three points are ahead of the center of the line". In this case, when it is determined that the acquired three points are closer than the center, three points are taken out in positive order from the first point (refer to step S401); Take out three points in reverse order.

Fig. 27 shows the correspondence between the value of tan ^-1 and the parameter of tan ^-1 . The value of tan ^-1 is the angle (degrees), and the parameter of tan ^-1 is dy/dx. The angle θ is represented by (no×360)/56.

By using a table indicating that the value of tan ^-1 corresponds to the parameter of tan ^-1 , calculation of tan ^-1 is not required. However, when the value of tan ^-1 is 0 to 180° (only the first quadrant and the second quadrant), the parameter of tan ^-1 corresponding to 180°<tan ^-1 <360° is obtained by calculation. For example, since the straight line passing through (0, 0) and (10, 5) is dy/dx=0.5 (dy=5, dx=10), it can be seen that it is located between no4 and no5. If the smaller no is selected in this embodiment, no=4. Also, since a straight line passing through (0, 0) and (-10, -5) is dy/dx=0.5 (dy=5, dx=10), no=4. However, since it is the value of the third quadrant, 28 is added to make no=32. That is, Θ ₁ =tan ^-1 ((y ₂ -y ₁ )/(x ₂ -x ₁ )) is equivalent to finding the angle between the straight line passing through the first point and the second point and the horizontal line, but the accuracy is allowed to be lowered. In this case, it can be replaced with no for obtaining the table.

If the value of tan ^-1 ((y ₂ -y ₁ )/(x ₂ -x ₁ )) obtained from the table is set to no ₁ , the tan ^-1 ((y ₃ -y _{2 )} obtained from the table )/(x ₃ -x ₂ )) is set to no ₂ , then the calculation of a=round(((Θ ₂ -Θ ₁ )×28)/(2×∏)) can be replaced by a=round (abs(no ₂ -no ₁ )/2).

Hereinafter, a specific description will be given with reference to FIGS. 1 to 4 .

Fig. 1 shows a curve passing through (0,0), (7,4), (10,10). The value of no ₁ is 4. The reason for this is (4-0)/(7-0)=0.571. The value of no ₂ is 9. The reason for this is that (10-4)/(10-7)=2. The angle mode a is 3 (a=round(abs(9-4)/2)).

Fig. 2 shows a curve passing through (0,0), (7,4), (13,16). The value of no ₁ is 4. The reason for this is (4-0)/(7-0)=0.571. The value of no ₂ is 9. The reason for this is that (16-4)/(13-7)=2. The angle mode a is 3 (a=round(abs(9-4)/2)).

Fig. 3 shows a curve passing through (0,0), (7,4), (12,17). The value of no ₁ is 4. The reason for this is (4-0)/(7-0)=0.571. no ₂ has a value of 10. The reason for this is that (17-4)/(12-7)=2.6. The angle mode a is 3 (a=round(abs(10-4)/2)).

Fig. 4 shows curves passing through (0,0), (7,4), (14,16). The value of no ₁ is 4. The reason for this is (4-0)/(7-0)=0.571. no ₂ has a value of 15. The reason for this is that (14-4)/(6-7)=-10. The angle pattern a is 6 (a=round(abs(15-4)/2)).

When such a table is used, the angle pattern can be obtained without calculating complicated trigonometric functions.

FIG. 18 shows the procedure of the first quadrant drawing process executed in step S409.

Next, referring to FIG. 18, the procedure of drawing the first quadrant will be described step by step.

Step S501: Determine whether the control sequence acquired in step S405 is finished.

When it is determined that the control sequence has ended (Yes), the process ends. When it is determined that the process has not ended (NO), the process proceeds to step S502.

Step S502: Depending on the value of the control column (values "0" to "7": refer to FIG. 13), the processing branches.

When the control value is "0", the process proceeds to step S503. When the control value is "1", the process proceeds to step S504. When the control value is "2", the process proceeds to step S505. If the control value is "3", the process proceeds to step S506. When the control value is "4", the process proceeds to step S507. When the control value is "5", the process proceeds to step S508. If the control value is "6", the process proceeds to step S509. If the control value is "7", the process proceeds to step S510.

Step S503: Increase the x value controlling the value in the x direction by 1. The process proceeds to step S511.

Step S504: Increase the x value controlling the value in the x direction by 1, and increase the y value controlling the value in the y direction by 1. The process proceeds to step S511.

Step S505: Increase the y value controlling the value in the y direction by 1. The process proceeds to step S511.

Step S506: Decrease the x value controlling the value in the x direction by 1, and increase the y value controlling the value in the y direction by 1. The process proceeds to step S511.

Step S507: Decrease the x value controlling the value in the x direction by 1. The process proceeds to step S511.

Step S508: Decrease the x value controlling the value in the x direction by 1, and decrease the y value controlling the value in the y direction by 1. The process proceeds to step S511.

Step S509: Decrease the y value controlling the value in the y direction by 1. The process proceeds to step S511.

Step S510: Increase the x value controlling the value in the x direction by 1, and decrease the y value controlling the value in the y direction by 1. The process proceeds to step S511.

Step S511: convert the points (x, y) calculated in steps S503 to S510 into drawing data. For example, plot point (x, y).

FIG. 19 shows the procedure of the second quadrant drawing process executed in step S410.

The second quadrant is y-axis symmetric with respect to the first quadrant. Therefore, the only difference from the first quadrant drawing processing procedure (see FIG. 18 ) is that the increase or decrease of x corresponding to the control value is reversed, and therefore, descriptions of steps S601 to S611 are omitted.

FIG. 20 shows the procedure of the third quadrant drawing process executed in step S411.

The third quadrant is symmetrical to the origin with respect to the first quadrant. Therefore, the only difference from the processing procedure of the first quadrant rendering procedure (see FIG. 18 ) is that the increase and decrease of x and the increase and decrease of y corresponding to the control value are respectively reversed, and therefore, descriptions of steps S701 to S711 are omitted.

FIG. 21 shows the procedure of the fourth quadrant drawing process executed in step S412.

The fourth quadrant is x-axis symmetric with respect to the first quadrant. Therefore, the difference from the first quadrant drawing processing procedure (see FIG. 18 ) is that the increase and decrease of y corresponding to the control value are reversed, and therefore, descriptions of steps S801 to S811 are omitted.

FIG. 22 shows coordinate data, scaled data, and quantized data.

It is the result of scaling and quantizing vector data (see FIG. 9 ).

FIG. 23 shows the results of rendering based on the quantized data shown in FIG. 22 .

The result of drawing the quantized data (see FIG. 22 ) by the drawing data conversion process (see FIG. 15 ) is shown. Characters can be drawn with high quality by curve drawing.

Fig. 24 shows the table editing processing procedure.

FIG. 25 shows a pattern of lines after display points have been changed.

FIG. 26 shows a graph drawing table after display points are changed.

Next, with reference to FIG. 1 , FIG. 12 , and FIG. 24 to FIG. 26 , the table editing processing procedure will be described step by step.

Step S901: find out the control bar passing through three points, and display the line pattern on the editing screen. The pattern of the line displayed on the editing screen is as shown in FIG. 1, for example. The pattern of the line passing through two points is displayed on the editing screen.

Step S902: Change the pattern of the displayed line while observing the screen. For example, edit the line pattern shown in FIG. 1 to the line pattern shown in FIG. 25 .

Step S903: The table is rewritten from the pattern of the line passing through the first point and the second point in the pattern of the changed line in the control column. The 1990th control column {0, 0, 1, 0, 1, 1, 1} of the curve table shown in Figure 12 is rewritten as the 1990th control column {0, 1, 0 of the curve table shown in Figure 26 , 1, 0, 1, 1}.

In this way, the contents of the curve table can be changed. Among them, the change result will affect all cases where the angles of the straight line passing through the first point and the second point and the straight line passing through the second point and the third point are divided into the same angle pattern.

The display procedure of the present invention has been described above with reference to FIGS. 14 to 21 and 24 .

For example, in the examples in FIGS. 14 to 21 and 24, step S401 to step S404 correspond to "concerning the given first point, second point and third point, determine the The step of the first position relationship between at least one party and the third point", step S405 corresponds to "from the pattern of at least one line prepared in advance, that is, the pattern of at least one line passing through the first point and the second point, select and determine Steps of a line mode corresponding to the first positional relationship of the selected line", step S409 to step S412 correspond to the step of "displaying the line passing through the first point and the second point on the display device according to the selected line mode". However, the example in FIGS. 14 to 21 and FIG. 24 is merely an example showing the display order of the present invention. A display sequence having any steps is included in the scope of the present invention as long as each step described above is performed.

According to the program and the recording medium of the present invention, it is possible not to obtain the locus of the line passing through the first point and the second point by calculation, but to select from at least one pattern of the line passing through the first point and the second point. A line pattern corresponding to the determined positional relationship, so that a line passing through the first point and the second point can be displayed. Therefore, it is not necessary to calculate the locus of the line passing through the first point and the second point through complicated calculations, and the line passing through the first point and the second point can be displayed at high speed.

In the above-mentioned embodiment, the case where characters are displayed has been described as an example, but the present invention is not limited thereto. The present invention can also be used in cases where graphics are displayed instead of text or in addition to text. In this case, by using a graphic display program instead of the character display program 41 or in addition to the character display program 41 , it is sufficient to use graphic data instead of the character data 42 or in addition to the character data 42 . The graphics display program may also include the same steps as the character display program 41 . Graphics may include part of characters, patterns, symbols, and the like.

As mentioned above, although this invention was demonstrated using the preferable embodiment of this invention, this invention is not limited to this embodiment, and is interpreted. It should be understood that the scope of the present invention is only interpreted based on the scope of technical solutions. Those skilled in the art can derive an equivalent range from the description of specific preferred embodiments of the present invention based on the description of the present invention and common technical knowledge. Specifically, patents, patent applications, and documents cited in this specification should be understood as if their contents themselves are cited as a reference to this specification, as if they themselves were described in this specification.

(industrial availability)

According to the display device, program, and recording medium of the present invention, it is possible not to obtain the locus of the line passing through the first point and the second point based on calculation, but to obtain the locus of the line passing through the first point and the second point from at least one pattern of the line passing through the first point and the second point. A mode of a line corresponding to the determined positional relationship is selected so that a line passing through the first point and the second point can be displayed. Therefore, it is not necessary to calculate the locus of the line passing through the first point and the second point through complicated calculations, and the line passing through the first point and the second point can be displayed at high speed.

In the present invention, a curve connecting the three points is drawn using a table showing the correspondence between the pattern of the line passing through the first point and the second point and the positional relationship of the three points. Therefore, drawing of a curve can be realized only by reading a table, and no complicated calculation is performed. As a result, a line passing through the first point and the second point can be drawn at high speed.

Furthermore, the angles of the straight line passing through the first point and the second point and the straight line passing through the second point and the third point are classified and tabulated. As a result, capacity can be reduced.

And only when the second point is located in the first quadrant, angle classification and tabulation of a straight line passing through the first point and the second point and a straight line passing through the second point and the third point are performed. Therefore, combinations of three-point positions can be reduced. As a result, the capacity can be further reduced.

Claims (6)

1. A display device comprising: a display device for displaying lines, and a control unit for controlling the display device, The control unit determines a first positional relationship between at least one of the first point and the second point and the third point for the assigned first point, second point, and third point, and determines Among the prepared at least one line pattern, that is, at least one line pattern passing through the first point and the second point, select a line pattern corresponding to the determined first position relationship, according to the selected a line mode to display a line passing through said first point and said second point to said display device, a plurality of regions are allocated around the second point, said third point is assigned to one of said plurality of regions, One area assigned the third point and an area different from the one area have different sizes. 2. The display device according to claim 1, wherein, further comprising a holding unit that holds pattern information indicating a correspondence relationship between the first positional relationship and the pattern of the at least one line, The selection of the mode of the line is performed with reference to the mode information held in the holding unit. 3. The display device according to claim 1, wherein, The first positional relationship is determined based on an angle between a first straight line connecting the first point and the second point and a second straight line connecting the second point and the third point. 4. The display device according to claim 3, wherein, The control unit determines a second positional relationship between at least one of the first point and the second point and the fourth point with respect to the first point, the second point, and the fourth point, The control unit selects a line pattern corresponding to the determined second positional relationship from among the at least one line pattern, a plurality of regions are allocated around the second point, said third point and said fourth point are assigned to the same area of said plurality of areas, A pattern of a line corresponding to the determined first positional relationship is the same as a pattern of a line corresponding to the determined second positional relationship. 5. The display device according to claim 1, wherein, The first point is assigned to the origin and the second point is assigned to the first quadrant. 6. The display device according to claim 1, wherein, only a part of the surrounding of the second point is allocated with a plurality of regions, The third point is assigned to one of the plurality of areas.

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