JPH09152857A - Character output device and character plotting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the number of pieces of data representing coordinate components of font data and to plot a character pattern with high quality. SOLUTION: By adding a connection situation flag showing a connection situation between adjacent segments to font data, date for one coordinate of Bezier control point showing skeleton line are omitted from font data, if 'G1 is continuous', and data for two coordinates of the control points are omitted to be stored in a font storage part 14 in the omitted form, if 'G2 is continuous'. Also, in the case of reading the font data, a control part 13 restores the omitted data based on the connection situation flag and generates and plots the character pattern based on the restored font data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a character output device used in a document creation device such as a Japanese word processor. In particular, a character pattern is formed by using font data in which data is omitted depending on the connection status between segments. The present invention relates to a character output device and a character drawing method for drawing.

[0002]

2. Description of the Related Art Conventionally, in a document creating apparatus such as a Japanese word processor, a skeleton font has come to be used in place of an outline font which describes the contour line shapes on both sides of a stroke forming a character pattern. . The skeleton font is described by decomposing strokes that form a character pattern into skeleton shapes and line width sample values.

In such a skeleton font, a stroke which is a component of a character is represented by skeleton and line width information. That is, as shown in FIG. 7, a core wire 1 represented by a cubic Bezier curve and its control points P0 to P3.
(Assuming that the parameter is represented by t, t = 0, 1/3, 2 /
Values W0, W1, W2 of the line width 2 at 4 points (3, 1)
The shape of the contour lines on both sides of the stroke is represented by W3.

At this time, the coordinates of the control points P0 to P3 of the Bezier curve representing the core line 1 are conventionally individually expressed as absolute coordinates (or relative coordinates to the previous control point). A stroke may consist of more than one segment. A segment is a minimum stroke unit in which the shape of the contours on both sides is represented by the core line + line width. Even in this case, the control point coordinates of the core lines of the segments were individually expressed.
Conventional character drawing technology, based on these control point information,
The stroke (each segment) is drawn individually.

[0005]

As described above, conventionally, the coordinate values of the control points P0 to P3 are individually represented.
Therefore, for one font, as point coordinate information, data will be held for the number of control points,
As a result, there was a problem that the amount of font data increased.

[0006] As part of measures for making the original pattern of characters beautiful, some characters are designed with the intention of smoothing strokes. However, in the conventional character drawing technique, since there is no particular awareness of such an intention, that is, the connection state between strokes, there is a problem such as deterioration in quality.

[0007] The present invention has been made in view of the above circumstances,
An object of the present invention is to provide a character output device and a character drawing method capable of reducing the number of data representing coordinate components of font data and drawing a character pattern with high quality.

[0008]

The character output device of the present invention has connection information indicating the continuity of each part constituting the character data, and the data indicating the shape of the part is omitted by this connection information. A font storage means for storing font data in a form, a data reading means for reading the font data stored in the font storage means, and the abbreviated data of the font data read by the data reading means based on the connection information. And a character drawing process for generating and drawing a character pattern based on the font data restored by the restoring process unit, and an output unit for outputting the character pattern drawn by the character drawing process. It was done.

Further, the character drawing method of the present invention uses font data which has connection information indicating continuity of each part constituting the character data, and in which data indicating the shape of the part is omitted by this connection information. Then, when the font data is read, the omitted data is restored based on the connection information, and a character pattern is generated and drawn based on the restored font data.

Accordingly, if the connection information is "G1 continuous", data for one coordinate of the Bezier control point representing the core line can be omitted from the font data, and if the connection information is "G2 continuous", the control point can be omitted. The data for the two coordinates can be omitted. "G1 continuous" represents a state in which the tangent direction of the core wire is continuous at the connection point with the core wire of the immediately preceding segment. "G2 continuous" represents a state where the curvature is continuous at the same connection point.

Even if such control points are omitted, the information of the correct control points can be obtained by the restoration process, and the data equivalent to the data necessary for drawing the character can be created. With this, it is possible to draw characters while ensuring a smooth connection.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration when a character output device according to an embodiment of the present invention is applied to a document creation device. This document creation device is provided with an input unit 1
1, a display unit 12, a control unit 13, a font storage unit 14, and a printing unit 15.

The input unit 11 is composed of, for example, a keyboard and inputs data and gives instructions. In this input section 11,
Various input keys such as a "character" key, a "number" key, and a "cursor" key are provided.

The display unit 12 is, for example, an LCD (Liquid Cry).
It consists of a display device such as a stal display) or CRT (CathodeRay Tube) and displays data. The control unit 13 is composed of, for example, a microprocessor, and controls the entire document creation process including the output process (print / display) of the character pattern. Here, the data read process unit 13a and the control point restoration process unit are used. 13b, the character drawing processing unit 13
c.

The data read processing unit 13a reads font data for each character from the font storage unit 14, and passes necessary data to the control point restoration processing unit 13b and the character drawing processing unit 13c. The control point restoration processing unit 13b restores the intermediate control point of the core line omitted in the font data based on the connection status flag added to the data. The character drawing processing unit 13c generates and draws a character pattern using the font data restored by the control point restoration processing unit 13b, and passes this to the display unit 12 and the printing unit 15.

The font storage unit 14 is composed of an external storage device such as a ROM or FDD (floppy disk device) / HDD (hard disk device), and stores font data. Particularly, in the present invention, the connection status flag indicating G1 continuity or G2 continuity is provided between the segments forming the character data, and the font data is stored based on the connection status flag with the data omitted.

The printing unit 15 is composed of a printer device and prints the generated character pattern on a paper surface or the like. Next, FIG.
The operation of the character output process in the embodiment will be described with reference to the flowchart shown in FIG.

For example, as shown in FIG. 3, it is assumed that core lines of two connected segments are omitted (line width information and contour lines on both sides are omitted). By representing the control points of the first segment by P1 ', P2', P3 'and the control points of the second segment by P1, P2, P3, the coordinates of each control point are as follows. Difference vector ΔPi (Δxi
, Δyi) is defined. In addition, Δx3 '> 0, Δx1>
0, Δy3 ′ = 0, and Δy1 = 0.

[0019]

(Equation 1)

When outputting a character pattern, the control unit 13
First activates the data reading processing unit 13a, reads the font data from the font storage unit 14, and from there, as control data P3 '(= P
The coordinate value (x3 ', y3') of 0), the connection status flag, L1 indicating the omitted coordinate of the control point P1, L2 indicating the omitted coordinate of the control point P2, etc. are read (step S1).

When the data necessary for drawing is read, the control unit 13 executes the following processing according to the connection status flag (G1 continuous, G2 continuous, other than that) of each stroke (segment) (step S12). Or S15).

"G1 continuous" means that the tangent direction of the core wire is continuous at the connection point with the core wire of the immediately preceding segment. "G2 continuous" means at the same connection point
Furthermore, the curvature is also continuous.

(1) Connection status flag: In the case of G1 continuity As a property of a cubic Bezier curve, control points P2 ', P3' (= P
0) and P1 are on a straight line. Using this, when the intermediate control point P1 of the current segment is considered in relative coordinates from the control point P3 ', P1 = P3' (x3 ', y3') + ΔP1 (Δx1, Δy1) = P3 '+ ΔP1 (L1, 0).

That is, the control point P1 is not a binary value of .DELTA.x1 and .DELTA.y1 but can be expressed by one L1 (= .DELTA.x1). Therefore, as shown in FIG. 4, control points P3 'and P1
Each xy coordinate value (data number: 4) can be replaced with the coordinate value of the control point P3 'and L1 (data number: 3),
The font data can be reduced by one coordinate value. In addition, in FIG. 4, (a) is a conventional method, (b)
Indicates the coordinate value expression of this method.

Incidentally, the connection status flag is actually required in the font data, but the number of data representing this is 2
It is about a bit and much smaller than that of the coordinate component of the control point. The connection status flag is added to the most significant bit or the least significant bit of each data.

Further, in summary including the example shown in FIG. 3, the equation for obtaining the control point P1 is as follows. P1 = P3 '+ ΔP1 (L1, L1 * Δy3' / Δx3 ') (a) where | Δx1 | ≧ | Δy1 | L1 = Δx1 P1 = P3' + ΔP1 (L1 * Δx3 '/ Δy3', L1) where │Δx1 │ <│Δy1 │ L1 = Δy1 However, when the connection status flag indicates G1 continuation (Yes in step S12), the control unit 13 reads the value of L1 (step S13), and then performs control. The point restoration processing unit 13b is activated to restore the coordinates of the intermediate control point P1 of the core line (step S14). In this case, the control point restoration processing unit 13b uses the above equation (a) to restore the coordinates of the intermediate control point P1 of the core line from the coordinates of the control point P3 'and the value of L1 by calculation.

Next, the control unit 13 is a character drawing processing unit 13c.
Is started, a dot pattern of a character is generated using the font data in which the coordinates of the intermediate control point P1 are restored as described above, and this is drawn (step S18).

(2) Connection status flag: G2 continuity In addition to the fact that the above equation (a) is established, the control point P2 (indicated by relative coordinates) of the current segment is P2 when the unique positional relationship of the control points is used. = P3 '(x3', y3 ') + ΔP1 (Δx1, Δy1)
+ ΔP2 (Δx2, Δy2) = P3 '+ (L1 + L2,-
Δy2 '* (L1 / Δx3') ² ).

That is, the control point P2 is Δx1, Δy1,
L1 and L2 (= Δx2) instead of four values of Δx2 and Δy2
It can be represented by two. Therefore, as shown in FIG. 5, the coordinate values of the control points P3 ', P1, P2 (the number of data: 6) are replaced with the coordinate values of the control point P3' and L1, L2 (the number of data: 4). Can be created, and the font data has coordinate value 2
The number can be reduced. In FIG. 5,
(A) shows the conventional method, and (b) shows the coordinate value expression of this method.

Further, in summary including the example shown in FIG. 3, the formula for obtaining the control point P2 is as follows. P2 = P3 '+ (L1 + L2,-[Delta] y2' * (L1 / [Delta] x
3 ') ² ) where Δx3' ≠ 0 Δy3 '= 0 L2 = Δx2 P2 = P3' + (-Δx2 '* (L1 / Δy3') ² , L1 +
L2) However, Δx3 ′ = 0 Δy3 ′ ≠ 0 L2 = Δy2 If the connection status flag indicates G2 continuous (Yes in step S15), the control unit 13 reads the value of L2 ( In step S16), the control point restoration processing unit 13b is activated to restore the coordinates of the intermediate control points P1 and P2 of the core line (step S17). In this case, the control point restoration processing unit 13b uses the above equations (a) and (b) to calculate L1
, L2, etc., the coordinates of the intermediate control points P1, P2 of the core are restored by calculation.

Next, the control unit 13 controls the character drawing processing unit 13c.
Is started, a dot pattern of a character is generated using the font data in which the coordinates of the intermediate control points P1 and P2 are restored as described above, and this is drawn (step S18).

When the dot pattern based on the font data is obtained in this way, the control section 13 outputs this dot pattern to the display section 12 or the printing section 15 (step S19).

As described above, by adding the connection status flag indicating the connection status between the adjacent segments to the font data, if "G1 continuous", data for one coordinate of the Bezier control point representing the core line is obtained. It can be omitted from the font data, and if it is "G2 continuous", data for two coordinates of the control point can be omitted, and as a result, data compression can be achieved.

Even if the control points are omitted, the information of the correct control points can be obtained by the above-mentioned processing, so that the data equivalent to the data necessary for drawing the character can be created and the connection status flag can be created. With this, it is possible to draw characters while ensuring that the segments are accurately connected.

That is, for example, in the case of the character ("a") as shown in FIG. 6A, the connection of the lines indicated by the dotted line (G1 / G2 connection) is made adjacent as shown in FIG. 6B. You can draw smoothly between segments.

For three or more segments, two adjacent segments may be considered as a pair. Further, in the above-described embodiment, the two curved line segments are considered, but the same idea can be applied between curved line segments / straight line segments. This is because, due to the nature of the Bezier curve, the straight line segment can be considered as a special case where the control points P1 and P2 are on the line segment P0-P3.

Further, as the connection relation between the parts forming the character, the description has been made between the segments in the stroke.
Such a connection relationship can be extended between strokes (outline of stroke) / decorative data, and also between segments in the ornamental data (minimum unit constituting an outline-expressed ornament).

Further, not only the core line font, but also the outline font in which the character contour line is represented by a cubic Bezier curve may use the same idea for the contour line itself. Further, in addition to fonts, if the data format is the same, it can be applied to, for example, graphics.

[0039]

As described above, according to the present invention, the font data having the connection information indicating the continuation status of each part forming the character data and omitting the data indicating the shape of the part by this connection information. By using this, when the font data is read, the omitted data is restored based on the connection information, and a character pattern is generated and drawn based on the restored font data. The effect is obtained.

(1) Data for expressing coordinates is reduced,
It is possible to reduce the overall font data amount and achieve data compression. (2) By using the connection information indicating the continuity of the segments, the connection of the line (core line or contour line) representing the shape of the part can be smoothly drawn, and thereby the quality of character drawing can be improved. it can.

(3) The present invention is not limited to the skeleton font, but can be applied to general outline fonts using contour information, and can also be applied to outline-type (including skeleton expression format) figures and the like.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration when a character output device according to an embodiment of the present invention is applied to a document creation device.

FIG. 2 is a flowchart showing an operation of character output processing in the same embodiment.

FIG. 3 is a diagram for explaining a connection status between segments.

FIG. 4 is a diagram for explaining a data omission method based on G1 continuity.

FIG. 5 is a diagram for explaining a data omission method based on G2 continuity.

FIG. 6 is a diagram for explaining a character drawing method using G1 / G2 continuation.

FIG. 7 is a diagram showing a core wire represented by a cubic Bezier curve.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Input part 12 ... Display part 13 ... Control part 13a ... Data reading process part 13b ... Control point restoration process part 13c ... Character drawing process part 14 ... Font storage part 15 ... Printing part

Claims (2)

[Claims] 1. A font storage unit for storing font data, which has connection information indicating a continuation status of each component forming character data, and omits data representing the shape of the component by this connection information. Data reading means for reading the font data stored in the font storage means, restoration processing means for restoring the omitted data of the font data read by the data reading means based on the connection information, and the restoration processing means A character output device comprising: a character drawing process for generating and drawing a character pattern based on the restored font data; and an output means for outputting the character pattern drawn by the character drawing process. 2. The font data is read by using font data having connection information indicating continuity of each part constituting character data and omitting data indicating the shape of the part by this connection information. At this time, a character drawing method is characterized in that the omitted data is restored based on the connection information, and a character pattern is generated and drawn based on the restored font data.