JPH03209499A - Forming method for outline font and drawing device for the same - Google Patents

Abstract

PURPOSE:To simplify a circuit and accelerate speed by using triangular element data with its character devided by a triangle in addition to the vector data of a contour line and generating the character by integrating these element data. CONSTITUTION:The contour line of a character D is composed of straight lines connecting points P0, P1-Pn and the character D is divided by triangles T0, T1-Tm with the three points as apexes. The contour line data are arranged while storing the coordinate values of the points P0, P1-Pn and the triangular data are arranged while designating the three apexes of the triangles T0, T1-Tm. A coordinate transforma tion part 13 calculates the coordinate values of the points, for which coordinate trans formation is executed to the apexes of the triangles for drawing the triangles, and investigates whether the coordinate values of the points are stored in a work data preservation part 16 or not, and the coordinate values of the points, to which the coordinate transformation is executed, are calculated and stored in the work data storage part 16. The coordinate transformation part 13 outputs the coordinate values of the points to a triangle drawing part 14 and the triangles are drawn in a frame buffer 17. Thus, the speed can be accelerated and the drawing part can be realized by the simple circuit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for forming an outline font for forming a character font and a drawing device therefor, and particularly to an outline font having character outlines as data.

[Conventional technology]

Regarding the conventional technology, the font outline diagram in Fig. 7 and the font outline diagram in Fig. 8
This will be explained with reference to the flowchart in the figure.

The outline of the conventional outline font is shown in Figure 7 (a
), straight lines, arcs, and Bezier curves.

It is expressed by a combination of curves such as C-spline curves, and the font data is composed of points U,, U! , --- [Consists of coordinates of each Jts and attributes for determining line type, etc.

In this at-line 7-ont printing process, Figure 7 (
The coordinates of the points U, , U, , U, , as shown in a) are read in step 41 of FIG. 8, and then in step 42.
Then, as shown in Fig. 7(b), in order to print the characters in the desired size, and sometimes with rotation, tilt, etc., the coordinates of the point tJo t [J, l ---* U13 are determined. calculate. Characters are drawn on the 7 frames P and F for each scan line, either from the larger y-coordinate value of the scan line person or from the smaller one.
This is performed by the process in step 5.

In step 44, as shown in FIG. 7(C), the intersection of the scan line person and the contour line is 20.2 m, 2. .

Find zs and draw segment 2.2 on scan 2 in
．． ．． 2 snow 2. Calculate. In Step 45, the drawing segments obtained in Step 44 are drawn (Z, Z, .

2.2. Write to the dot in the frame buffer that corresponds to the dot above. By performing steps 44 and 45 for each scan line, the process shown in FIG.
Characters are formed as shown.

In addition, in step 43, it is determined whether or not drawing of the drawing segment has been completed for all scan lines that intersect with the character, and if it has been completed, it is assumed that the entire character shape has been drawn. Character drawing ends.

When drawing characters using this conventional outline/7 ont, internal determination of character shape is performed for each scan line.
Steps 44 are generally performed by determining drawing segments on the scan line, but for this internal determination, all outline data is coordinate-transformed in step 42. I need to be there.

A drawing device for drawing this outline/7 ont is shown in the professional diagram of FIG. This device, control o-
111b and an external memory 12, the controller llb is divided into a coordinate conversion section 13b and a drawing section 14b, and the coordinate conversion section 13b performs all the processing in steps 41 and 42 in FIG. Part 14b is step 43
Then, the processes of step 44 and step 45 are performed. The external memory 12 also includes a font data storage section 15, a processed data storage section 16, and a frame buffer 17.

As mentioned above, in order to calculate the drawing segment on the scan line by internal determination, all contour data must be coordinate transformed, so this controller 1
In step 2b, first, the coordinate transformation unit 13b coordinately transforms all of the contour line data stored in the 7-ontodata storage unit 15,
The processed data is stored in the processed data storage unit 16. After all the processing by the coordinate conversion section 13b is completed, the drawing section 14b becomes operational for the first time, calculates a drawing segment based on the data in the processed data storage section 16, and draws it on the frame buffer 17.

[Problem to be solved by the invention]

In character drawing using the conventional outline font described above, internal determination of the character shape is performed for each scan line, but this internal determination requires that all outline data be coordinate-transformed in step 42. , the number of intersections with the contour line obtained in step 44 on the scan 2 input may vary greatly depending on the position of the scan line and the character, so it is difficult to draw characters using this outline font using hardware. When doing so, the disadvantage is that the speed cannot be increased very much and the circuit becomes complicated.

That is, when implemented as hardware as shown in FIG. 9, it is not possible to perform pipeline processing in which the coordinate transformation section 13b and the drawing section 14b operate at the same time.
Even if it is made into hardware, it cannot be made much faster. The processing in the drawing section is complicated because the number of intersections with the contour line differs for each scan line, and the circuit becomes accordingly complex.

The purpose of the present invention is to solve such problems and draw characters using data divided into triangles and font data, so character formation only requires drawing each triangle, and it is possible to create a character using hardware. An object of the present invention is to provide a method for forming an outline font and a drawing device thereof, which can be performed using a relatively simple circuit and which can speed up character drawing.

[Means to solve the problem]

The configuration of the present invention is to provide a method for forming an outline font in which the shape of a character is expressed by vector data of the outline of the character, in addition to the vector data of the outline, triangular element data obtained by dividing the character into triangles. using
The character is characterized in that the character is formed by accumulating these element data.

Further, the outline font drawing device of the present invention has a configuration including a font data storage unit that stores font data representing the outer shape of a character as triangular data, and a coordinate transformation unit that coordinates transforms data from the font data storage unit. , a processing data storage section that stores the output of the coordinate transformation section and outputs it to the coordinate transformation section; a triangle drawing section that accumulates and draws the output of each triangle according to the coordinate values of each triangle from the coordinate transformation section; The apparatus is characterized by comprising a frame buffer for storing an output image from the unit.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of an outline font drawing device according to a first embodiment of the present invention, FIG. 2 is a flowchart of the outline font drawing process of FIG. 1, and FIGS.
) is an outline diagram illustrating the formation state of the outline font used in FIG. 1.

Outline Font Co., Ltd. used in this example, Figure 3 (
As shown in a), the outline of the character rDJ is at the point P Oe
Pl m ---e Consists of a straight line connecting Pn, and points P
The character rDJ is triangulated by a triangle T 6 # Tl e ---e Tin having three points among OtPt p --- and P n as vertices.

This font data consists of outline data B and triangle data C, and as shown in Table 1, outline data B is
This is an array in which the coordinate values of the point P・e Plt +++ I pn are stored, and the triangle data C is the triangle 'r, t
T 1 m ---s This is an array specifying the three vertices of Tm. Here, the trinomial point of triangle To is FlitP, ◎
+P! It shows that it is B.

Table 1 Triangle Data C If triangle T/ is a triangle whose three vertices are points Pl e PJ e Pk, the first element of this array has i
The values of j and k are stored.

Next, an example of the outline font drawing process of this embodiment will be described.

The font data storage section 15 stores font data as shown in Table 1. The coordinate transformation unit 13
Step 21 of the figure. Steps 22 and 23 are performed, and in step 21, the font data storage section 15 is
It is checked whether there are any triangles that have not yet been drawn among the triangles of the triangle data C stored in the . If all the triangles have been drawn, the entire character has been drawn, and the printing process is complete. If there are triangles that have not yet been drawn, the process moves to step 22 in order to draw one of the triangles. For convenience, assume that the triangle is T/, that its vertices are PiPj, PH(, and that the coordinates of the point Pl s PJ * Pk are converted to points Qi*Qj, Qk. Step 22 is based on the triangle data C. Read the index "aJek" of the vertex of triangle T/.

In Step 23, the vertices PlsPJsPk of triangle T/
Find the coordinate values of points Qi, Qj, and Qk whose coordinates have been transformed. This process has already been performed at the point Q in the processing data storage unit 16.
Check whether the coordinate values of i, Qj = Qk are stored, and if stored, read the coordinate values,
For points that are not stored, a coordinate transformation is calculated for the coordinate values stored in the contour data B, and the coordinate values of the transformed points are calculated, and the values are stored in the processing data storage unit 1.
6.

The coordinate transformation unit 13 converts the point Q obtained in the process of step 23
The coordinate values of i-Qj-Q/ are output to the triangle drawing section 14. The triangle drawing unit 14 performs the triangle drawing process in step 23, and this triangle drawing unit 14 converts the triangle S/ whose apex is the point Qi e Qj#Q/ input from the coordinate conversion unit 13 into a 7 frame buffer 17. to draw. In this way, the triangular T/ portion of the character is drawn by the processing of steps 22, 23 and 24.

By continuing this process for the triangles T o, T, . . . , Tm, characters are drawn as shown in FIG. 3(C).

In the above description of the drawing process, it has been described according to the flow shown in FIG. 2, but in the drawing device shown in FIG.
Triangle Sl! When the data of the vertices Qi yQj and Qk are outputted to the triangle drawing unit 14, the processing for the next triangle to be drawn is immediately started, so that the coordinate conversion process and the drawing process can be performed simultaneously.

FIG. 4 is a block diagram of an outline font drawing device according to a second embodiment of the present invention, FIG. 5 is a flowchart of an example of the font drawing process of FIG. 4, and FIGS. FIG. 2 is an outline diagram illustrating the configuration of an outline font according to an embodiment.

As shown in FIG. 6(a), the font of this embodiment has an outline composed of straight lines or curved lines connecting points KO, , ..., Kn, and the characters are .

---Assume that it is divided by SXm.

Each element is either a triangle with vertices at three points among the points KO, ..., or the starting point, end point and point KO, Kl, -- of one curve on the contour line. - It is a part concave by two straight lines connecting one point in Ka and the curved line. The former is assumed to be a triangular element, and the latter is assumed to be a fan-shaped element, and the points of the sector-shaped element such as the interlocking point, the starting point and end point of a curve, and the corner points of two straight lines are called vertices. As shown in Table 2, this font data consists of outline data D and triangle data E, and the outline data D is
This is an array in which the coordinates of the points KO, , , , , and an attribute indicating what kind of point in the outline the point is are stored. Here, at the top of element Xo,
, K, , K1°.

Table 2 Contour line data D Element data E This attribute can be used, for example, to determine whether the end point is a straight line or a curved line, whether it is a straight line starting point or a curved starting point, whether it is the starting point of a closed curve in a contour, or if it is in the middle. , or the end point. In addition, the triangular element data E includes elements X,
, j and k
The value of is stored.

Next, the outline/7-ont drawing process of this embodiment will be explained. The difference between this font and the font of the first embodiment is that the outline includes a curved line and the characters are divided not only by triangles but also by triangular elements and fan-shaped elements.

The differences in drawing processing caused by this expansion will be explained below.

The specific differences are that in Fig. 5, Step 31 and Step 32 are added to the flow in Fig. 2, and in Fig. 4, a linear approximation section 18 is added to Fig. 1. be. The determination in steps 31 and 31 is performed by the coordinate conversion unit 13a, and when this is a triangular element, the converted coordinates of the vertices are output to the triangle drawing unit 14a as in the first embodiment.

When the element is a fan-shaped element, the coordinate conversion unit 13a
outputs the transformed coordinates of the vertex to the linear approximation unit 18. The linear approximation unit 18 divides the sector element into several triangles as shown in FIG. It is output to the drawing section 14a. Other processing and operation of the printing device are the same as in the first embodiment.

〔Effect of the invention〕

As explained above, the present invention adds not only outline data expressing the character shape but also data for triangulating the character as outline font data, so that the drawing process in character drawing can be performed in a triangular manner. Not only is this possible through a simple process called drawing processing, but when it is made into a single hardware, coordinate conversion processing and drawing processing can be executed at the same time in a pipeline, which speeds up the process and further simplifies the drawing process. As a result, the effect that the drawing section can be realized with a simple circuit can be expected.

[Brief explanation of drawings]

FIG. 1 is a professional diagram of the first embodiment of the present invention, and FIG. 2 is a flowchart of the outline font drawing process of FIG. 1.
3(a), (b), and (C) are plan views explaining the structure of the out-twin font shown in FIG. 1, FIG. 4 is a block diagram of the second embodiment of the present invention, and FIG. 5 Sakaki; (6)
is a flowchart of the outline font drawing process, Figures 6(a) to (C) are plan views explaining the configuration of 79 trines and 7 onts in Figure 4, and Figures 7(a) to (d) are conventional diagrams. Outline drawing explaining the structure of an example outline font, No. 8
The drawings are a flowchart of the outline font drawing process shown in FIG. 7, and FIG. 9 is a professional diagram of a conventional outline font drawing device. A: Scan line, B, D: Contour data, C, E - Triangle data, ll
, lla, 11b...controller, 12...
...external memory, 13゜13a, 13b・
---Coordinate conversion section, 14, 14a°°. ...Triangle drawing section, 14b...Drawing section, 15
......Font data storage section, 16...
Processed data storage unit, 17... Frame buffer, 18... is approximation unit, 21 to 24, 31, 3
2.41-45...Processing steps.

Claims (2)

[Claims] (1) A method for forming an outline font in which the shape of a character is expressed by vector data of the outline of the character, using triangular element data obtained by dividing the character into triangles in addition to the vector data of the outline, A method for forming an outline font, characterized in that the characters are formed by accumulating these element data. (2) A font data storage unit that stores font data representing the outer shape of a character as triangular data, a coordinate conversion unit that converts the coordinates of data from this font data storage unit, and stores the output of this coordinate conversion unit and A processed data storage unit that outputs to the coordinate conversion unit, a triangle drawing unit that accumulates and draws the triangles according to the coordinate values of each triangle from the coordinate conversion unit, and a frame buffer that stores output drawing lines from the triangle drawing unit. An outline font drawing device comprising: