JPH06301755A - Picture preparation device - Google Patents

Abstract

PURPOSE:To plot lines for which a thick pen point is used at a high speed by utilizing the coordinate values successively inputted by a coordinate input device of a pill or the like. CONSTITUTION:This device is composed of the coordinate input device 101, an external storage device 102, a display device 103 and a CPU 104. The inside of the CPU 104 is composed of an operation processor 107 such as a microprocessor or the like and a memory 108 for storing data required for the processings of programs, pen graphics and a thinning possible number or the like. Thinning numbers for respective directions for the respective pen graphics are stored in the memory 108 beforehand, the CPU 104 plots the pen graphics on the display device 103 only when it is required while referring to the information and thus, thick lines can be plotted at a high speed without performing uselss plotting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image creating apparatus which creates an image by electronic processing and draws the image on an output device, and in particular, a pen figure representing a pen tip is used to speed up a thick line. The present invention relates to an image creating apparatus capable of drawing on a screen.

[0002]

2. Description of the Related Art Recent rapid advances in electronic technology have made it possible to create an image by electronic processing and draw it on an output device such as a display.

Such an electronic image is electronically imaged because it is easy to store, partially modify, copy, etc., and because a pen, paper, paint, etc. are not required to create the image. An image forming apparatus, that is, an image forming apparatus is used in a very wide range of fields. For example, there are some that are simply used for drawing children,
Some are offered for advanced design.

By the way, when a figure is created, a line is one of the most basic figures, but conventionally, in an image forming apparatus, a figure representing a pen tip having a different size or shape is used and it has various thicknesses. A line figure is created. That is, when a thin line is drawn, dots are drawn continuously, whereas a thick line is drawn by drawing using a figure representing a pen tip instead of a point. The graphic representing the pen tip will be referred to as a "pen graphic" here. Example of "pen figure"
It shows in (a). An example of a thick line created using this “pen figure” is shown in FIG.

[0005]

[Problems to be Solved by the Invention]
The method of drawing a thick line using the "pen figure" was as follows.

1. The coordinates of the point P in the middle are generated from the coordinates of the points A and B on both ends of the input line segment. In this method, various algorithms have been developed as a method of drawing a straight line figure.

2.1. A "pen figure" is drawn centering on the point P generated in.

In this method, one "pen figure" is drawn for one point P. As a matter of course, since the "pen figure" is composed of a plurality of dots (dots), the whole drawing is slower than the case of a thin line in which only one dot needs to be drawn for one point. Become.
The extent of the delay is, for example, when the size of the “pen figure” is a rectangle of 32 × 32 dots, the “pen figure” is composed of 32 × 32 = 1024 dots. Therefore, since a dot of 1024 dots is drawn with respect to drawing of one dot when writing a thin line, in the worst case, it takes 1024 times as long as the drawing time. Actually, the process of drawing a point includes a process other than the process of drawing a point, and at the same time, a device for processing a plurality of points (for example, writing 8 bits horizontally arranged at the same time) is also performed. Although it is not simply 1024 times, there is a problem that the processing becomes very slow in any case.

[0009]

In order to solve this problem, in the image forming apparatus of the present invention, dots that can be thinned out at the time of drawing in the pattern of the figure representing the pen tip, depending on the direction of the line. A numeric parameter that represents a number (here,
(Hereinafter referred to as "thinning possible number"), a pen tip according to the storage means for storing the line figure, the direction of the line to be drawn when drawing the line figure, and the numerical parameter according to the direction of the line. And a means for switching whether or not to draw the graphic pattern representing

[0010]

If the drawing using the thinnable number is judged to be unnecessary, the pen figure is not drawn, so that unnecessary drawing is not performed and the whole drawing becomes faster.

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

An example is shown in which a thick line is drawn from point A to point B shown in FIG. The conventional method is shown in FIG. From point A to point B, I draw a pen figure for each dot. In this case, 13 pen figures will be written.

By the way, FIG. 3C shows a pen figure drawn every two dots. In this case, as the created figure, a figure equivalent to that in FIG. 3B is drawn, but only seven pen figures are drawn.

On the other hand, FIG. 3D shows a pen figure drawn every 3 dots. In this case, a dropout as indicated by the symbol X occurs. Therefore, in such a pen figure, it is not appropriate to draw every 3 dots.

Next, consider the case where an oblique line is drawn as shown in FIG. FIG. 4B shows drawing every other dot, FIG. 4C shows drawing every two dots, and FIG.
Is drawing every 3 dots. As is apparent from these figures, this pen figure may be drawn every three dots when it is drawn obliquely.

As is clear from the above description, depending on the type of pen figure and the drawing direction, it is decided how many dots may be drawn (this is named as "thinning possible number"). come. Therefore, the thinning number for each direction is stored in advance for each pen figure, and the pen figure is drawn only when necessary while referring to the information, so that unnecessary drawing can be performed at high speed. You can draw thick lines.

[0017]

1 is a block diagram of an embodiment of an image forming apparatus of the present invention.

The image forming apparatus includes a coordinate input device 101 such as a tablet, a digitizer, a mouse, a hard disk,
An external storage device 102 such as a floppy disk, a display device 103, and a CPU 104 are provided, and the coordinate input device 101, the external storage device 102, and the display device 103 are connected to the CPU 104, respectively. In some cases, the keyboard 105 and the printer 106 may be provided. The inside of the CPU 104 includes an arithmetic processing unit 107 such as a microprocessor, a program, a memory 108 for storing data necessary for processing such as a pen figure and a thinning-out possible number, an interface circuit 109 for connecting to an external device, and the like. It

In this embodiment, the coordinate input device 101 shown in FIG.
A thick line is created along with the coordinate data input from.
The result is displayed on the display device 103.

FIG. 5 shows a flowchart for drawing a thick line in the image forming apparatus of this embodiment. Note that the flowchart is programmed and stored in the memory 108, and the arithmetic processing unit 107 reads the program,
Based on this, the processing shown in the flowchart is executed in cooperation with peripheral devices.

First, in step S501, the coordinate values of the start point A and the end point B are input via the coordinate input device 101.
Here, it is assumed that the start point A and the end point B have different coordinate values.

Next, in step S502, the processing point P to be processed is set to the starting point A. In addition, the current drawing direction w is
Set to 0 (undetermined). Here, the value of w is related to the drawing direction: 0: not determined 1: rightward direction 2: upper right direction 3: upward direction 4: upper left direction 5: left direction 6: left lower direction 7: lower direction 8: lower right We will use nine numerical values for directions.

Then, the thinning-out possible number for each direction is the array M [w] (1) for the direction w (1≤w≤8).
≦ w ≦ 8).

FIG. 6 shows an example (a) of a pen figure and a table (b) of the number of possible thinnings for the pen figure. The method for determining the number of possible thinning-outs will be described later.

In the next step S503, the thinning-out number m is set to zero.

In the next step S504, it is determined whether the processing point P coincides with the end point B. If they match, the process moves to step S512.

In the next step S505, a processing point P'following the processing point P is obtained from the sequence of points from the starting point A toward the ending point B, and the direction w '(1) from the processing point P toward P'is determined. ≤
Find w ′ ≦ 8). As a method of obtaining the processing point P ', various algorithms have been conventionally known as a method of generating a digital straight line.

In the next step S506, it is determined whether w'is the same as w. If they are different, the process proceeds to step S510. At the starting point A, w is initially set to 0, so that the process always moves to step S510.

In the next step S507, the thinning-out number m is incremented by 1.

In the next step S508, the thinning-out possible number M [w] in the direction w and the thinning-out number m are compared. If m
If> M [w], further thinning cannot be performed, and the process proceeds to step S511. If m ≦ M [w], it is still possible to thin out, and the process proceeds to step S509.

In the next step S509, the processing point P is replaced with the processing point P '.

Process S510 is a process when the drawing direction is changed. First, the pen figure Z is drawn around the processing point P at the tip which has been advanced so far. After that, the processing point P is replaced with the processing point P ′. Also, replace w with w '. Then, the process proceeds to step S503.

In step S511, the pen figure Z is drawn around the processing point P. After that, the process point P is replaced with the process point P ′, and the process proceeds to S503.

In step S512, it is checked whether the thinning-out number m is 0. If not 0, in step S513.
The pen figure Z is drawn around the processing point P, and the process is ended.

7 and 8 show examples of thick line drawing by the image forming apparatus of this embodiment. The pen figure used is Figure 6 (a).
It is shown in.

7 (a) and 8 (a) are examples of the starting point A and the ending point B, and the straightening gradients of the straight lines to be drawn are different. FIG. 7B and FIG. 8B are examples of thick line drawing for each. Circles and triangles respectively indicate the loci of the processing points P. A circle is used to draw a pen figure. The numbers written on the pen figures indicate that they are drawn corresponding to the circles of the same number.

The case of FIG. 7 will be described with reference to the flowchart. First, as initial settings, processing S501 and processing S502 are executed. After that, m is set to 0 and the process proceeds to step S504. Since P is now the starting point A, the processing proceeds to step S505, 2
The point P'and the direction w'are obtained. Where the direction w'is 1
(To the right). In step S506, w (= 0) and w '
Since (= 1) is not equal, the process advances to step S510 to draw a pen figure at the starting point A which is the current processing point. afterwards,
The process returns to step S503 with w being 1 and P being the second point (m is initialized after drawing).

In the second processing, the processing S503, 504
After that, the third point P ′ and the direction w ′ are obtained at 505. The direction w'is 1 and coincides with w, and the process proceeds to step S507. 1 is added to the current value 0 of m, and 1 is set as a new value of m. In step S508, m (= 1) is compared with M [1] (= 1), and since they are equal, the pen figure is not drawn at the second processing point, and the third point is processed as the processing point in step S509. The process returns to S504 (m is not initialized because it is not drawn).

In the third processing, the processing point P'and the direction w'of the fourth processing point are obtained in processing S505 after processing S504.
The direction w'is 1 and coincides with w, and the process proceeds to step S507. 1 is added to the current value 1 of m, and 2 is set as a new value of m.
In processing S508, m (= 2) is compared with M [1] (= 1). Since m> M [1], the process proceeds to processing S510, and the pen figure Z is drawn at the current processing point (third point). The fourth point is set as a new processing point, and the process returns to step S503.

The fourth processing point becomes the fifth processing point without being drawn in the same processing flow as the second processing point.

In the processing of the fifth point, the processing point P'and the direction of the sixth processing point are obtained in processing S505. At this time,
The direction w ′ becomes 2 (upper right direction), and in process S506,
It is determined that it is different from the current w (= 1), and the process S5
In step 09, a pen figure is drawn at the fifth processing point, which is the current processing point. After that, processing is performed with w being 2 and P being the sixth point S50.
Return to 3.

Regarding the sixth processing, the processing point P'and the direction of the seventh processing point are obtained in processing S505. At this time, the direction w'becomes 1 (to the right) again, and in processing S506. ,
It is determined that it is different from the current w (= 2), and the process S5
In step 10, a pen figure is drawn at the sixth processing point, which is the current processing point. After that, processing is performed with w set to 1 and P set to 7th point S50.
Return to 3.

The seventh point is the second point, the eighth point is the third point, and the ninth point is
The fourth point and the fourth point have the same processing flow.

Although the tenth point is the end point B, processing S504.
At the processing point P, the processing point P is determined to be the end point B, and the process proceeds to step S512. In step S512, it is determined whether the value of m is 0.
Since the value of m is 1, the process proceeds to step S513, the pen figure Z is drawn at the end point B, which is the current processing point P, and the entire process ends. If m is determined to be 0 in step S512, it means that drawing was performed at the processing point immediately before, and in this case, drawing is not performed at the end point.

After all, the drawing of the pen figure is performed at the start point, the third processing point, the fifth processing point, the sixth processing point, the eighth processing point, and the end point (the tenth processing point), respectively.

As is clear from the above, it is understood that the pen figure Z is always drawn at the start point and the points before and after the direction changes.

The same processing is performed in the case shown in FIG. 8, and the pen figure Z is drawn at the start point, the fourth processing point, the fifth processing point, and the end point (eighth processing point).

Next, a method of obtaining the thinnable number will be described.
The thinnable number is a numerical parameter that exists with respect to the direction in which the processing point moves when drawing a line (normally 8 directions). The number of dots of the shortest one of the obtained lengths of the line segments is -1. The reason is that the line segment extending in the moving direction becomes a connected line segment even if the line segment is moved and drawn in the direction. In other words, the length of the line segment-1
It means that you don't mind thinning it out.

FIG. 9 shows a state in which the pen figure of FIG. 6A is decomposed in eight directions. In FIG. 9A, the number of dots of the shortest line segment in the left-right direction is 2, and thus the thinnable number is 1. In FIG. 9B, the number of dots of the shortest line segment in this case is 3 in the upper right direction or the lower left direction, and thus the thinnable number is 2. FIG. 9C shows the vertical direction. In this case, the number of dots of the shortest line segment is 2, and therefore the thinnable number is 1. FIG. 9D shows the case of the lower right or upper left direction. In this case, the number of dots of the shortest line segment is 3, and thus the thinnable number is 2. It can be seen from FIG. 9 that the number of possible thinning-outs in each of the eight directions is the table of FIG.

FIG. 10 and FIG. 11 show examples of other pen figures and the number of thinning-out possible corresponding to each.

FIG. 10A shows a square pen figure, and FIG.
(B) is a table of the thinning-out possible numbers corresponding thereto. In the left-right direction, the number of dots is 2, and therefore, the thinnable number in the right and left directions is 1, respectively. In the vertical direction, the number of dots is 5, and therefore, the number of dots that can be thinned out in the upward and downward directions is 4. The number of dots of the shortest line segment is 1 in the upper left direction, the lower right direction, the upper right direction, and the lower left direction. Therefore, the thinnable number is 0 in these directions.

FIG. 11 (a) is a pen figure with diagonal lines, and FIG.
1 (b) is a table of the number of possible thinning-outs corresponding thereto.
The number of dots in each of the left-right direction, the up-down direction, the upper left direction, and the lower right direction is 1. Therefore, the thinnable number is 0 in these directions. The number of dots is 4 in the upper right and lower left directions, and the thinnable number is 3 in these directions.

As described above in detail, it is possible to draw a thick line at high speed by simply adding a small amount of thinning-out possible number information to the pen figure data, and it is easy to obtain the thinning-out possible number. Is.

[0054]

The image forming apparatus according to the present invention stores a numerical parameter representing the number of dots that can be thinned out at the time of drawing in accordance with the direction of a line in a pattern of a figure representing a pen tip. A storage means and a means for, when drawing a line figure, switching between drawing and non-drawing of a graphic pattern representing a pen tip according to a direction of a line to be drawn and a numerical parameter corresponding to the direction of the line. Since it is provided, high-speed thick line drawing can be performed without performing unnecessary drawing.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of an image forming apparatus according to the present invention.

FIG. 2 is a diagram showing an example of a pen figure and a thick line created using the pen figure.

FIG. 3 is an explanatory diagram for explaining the principle of the present invention.

FIG. 4 is another explanatory diagram for explaining the principle of the present invention.

5 is a flowchart showing a flow of processing for drawing a thick line in the image forming apparatus shown in FIG.

FIG. 6 is a diagram showing a pen drawing and an example of the thinning-out possible number.

7 is a diagram showing an example in which a thick line is drawn by using the image forming apparatus shown in FIG.

8 is a diagram showing another example in which a thick line is drawn by using the image forming apparatus shown in FIG.

FIG. 9 is a diagram for explaining how to determine a thinnable number.

FIG. 10 is a diagram showing another pen figure and an example of the thinning-out possible number.

FIG. 11 is a diagram showing still another pen figure and an example of the thinning-out possible number.

[Simple explanation of symbols]

 101 coordinate input device 102 external storage device 103 display device 104 CPU 105 keyboard 106 printer 107 arithmetic processing device 108 memory 109 interface circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuaki Kayoshi 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka

Claims (1)

[Claims] 1. An image creating apparatus for creating a line figure using a pattern of a figure representing a pen tip, based on coordinate points input via a coordinate input means, wherein a pattern of a figure representing the pen tip is created. On the other hand, according to the direction of the line, a storage unit that stores a numerical parameter that represents the number of dots that can be thinned during drawing, and the direction of the line to be drawn when drawing a line figure and the line An image forming apparatus comprising: means for switching whether or not a graphic pattern representing a pen tip is drawn according to a numerical parameter according to a direction.