JP3213202B2 - Output device and line drawing processing method of output device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an output device capable of executing a line drawing process, and more particularly, to a polypen corresponding to a line width for drawing a line having a line width of 2 or more and performing the line drawing process. The present invention relates to an output device and a line segment drawing method performed by the output device.

[0002]

2. Description of the Related Art A line drawing process in a conventional output device will be described below with reference to FIGS.

In a conventional drawing library, a polypen corresponding to a line width is created in order to draw a line having a width of 2 or more.
Line data is drawn by extracting pen data according to the requested line width. Here, the polypen and its data structure will be described.

[0004] As shown in FIG. 8, a poly pen (hereinafter referred to as a pen) is a method in which a 1/4 circle having the same radius as the line width W is formed into a poly line according to an appropriate division rule, and a poly vertex is moved from one vertex to the next vertex. Vector is a drawing element (hereinafter called pen step)
It is assumed that. A pen corresponding to one line width starts with a horizontal step and ends with a vertical step.

As shown in FIG. 9, each pen step has, as data, the inclination, the direction from the center to the vertex, and the coordinates of the vertex. Each pen step has data in which these three types of values constitute one set, and entries for all step data are sequentially held from the line width “0” to the maximum width.

Further, entries for the horizontal pen step and entries for the vertical step are stored as a table corresponding to each line width, and pen table data of a required line width is extracted by searching this table.

As described above, in the conventional pen step data processing, since the pen step data is continuously stored in the pen step table C from the minimum line width to the maximum cache line width, the designated line width value is not changed. The entry is to the index A of the horizontal pen step and the index B of the vertical pen step.

Next, generation of pen step data will be described.

Since the polypen data is line-symmetric data having a boundary of 45 degrees, the data is compressed and held by the following method in order to reduce the memory usage.

That is, in a pen step (hereinafter referred to as an up step) which is between 45 degrees from the horizontal, an increment of x and y from one step to the next step is represented by d, respectively.
Assuming x and dy, the increment of a pen step (hereinafter referred to as a down step) between 45 degrees and the vertical is obtained by exchanging dx and dy of an up step at a line symmetric position, and this (dx, dy) ) (Hereinafter referred to as a step relation) as a set of data corresponding to each pen step, pen value data can be generated from this value.

For one step relation, there are two possible tilts of the pen step, an up step and a down step. Therefore, as shown in FIG. 10, (1) a step relation table (hereinafter referred to as RelTable) is used as a data table. ), (2) a tilt table for the up step (hereinafter referred to as UpSlopeT)
(3) Inclination table for down step (hereinafter referred to as DownSlopeTable)
Are prepared so that these tables can be searched with the same entry.

Further, (4) a table (hereinafter referred to as S) in which these entries correspond to each up step of all line widths.
(5) Line width and StepTa
ble and the table shown in FIG.
(referred to as “enTable”), it is possible to search for polypen data from the line width and generate pen step data.

Next, data processing from a line width designation request to drawing of a pen will be described with reference to a flowchart shown in FIG.

FIG. 11 is a flowchart showing an example of a data processing procedure from a line width designation request to a pen drawing in a conventional output device. (1) to (10)
Indicates each step.

After the line width is specified, it is determined whether or not the corresponding pen is cached (1). If YES, the process proceeds to step (10), where pen step data is searched (10), and step (7) is performed. Proceed to).

On the other hand, if the determination in step (1) is NO, it is determined whether or not the compressed data of the corresponding pen is held (2). If YES, the process proceeds to step (9) to search for the compressed data. And return to step (5).

On the other hand, if the determination in step (2) is NO, poly pen data is created (3), converted into compressed data (4), expanded into pen step data (5), and the pen is stored in the RAM area. (6), a pen is selected (7), and a drawing process is performed (8).

Hereinafter, the holding of the pen step data and the compressed data will be described.

In the prior art, after creating polypen data corresponding to all of the minimum line width (0) to the maximum line width, the data is compressed, stored in a file, and stored in advance in a ROM area of the printer. I do. Furthermore, expand the compressed data of the line width that seems to be used frequently at the time of program initialization in advance and create pen step data,
The data is stored in the RAM area as a data table (this is called a cache pen).

When a line width designation command is issued during execution of a program as shown in FIG. 12, if the requested width has already been expanded as a cache pen, the entry is returned as it is. Is R
The compressed data stored in the OM is read, decompressed, and pen step data is created and used.

As described above, storing compressed data in the ROM reduces the amount of memory used in the RAM area, and caches frequently used pen step data in the RAM area to increase the efficiency of line width selection. Is being planned.

[0022]

As described above, in order to use a polypen corresponding to a certain line width, a polypen data creation process (first process) and a second conversion process to compressed data (first process) are performed. 2) and a process of expanding the data into pen step data (third process).
Although it is possible to start from any data format, if the process is started by creating the polypen data of the first process, an area for holding the data is not required in advance, and the memory usage is minimized, but the creation is not required. There is a problem that it takes time, and if the data of the third processing is created in advance, there is a problem that a large area for holding the data is required instead of the shortest creation time.

Since the number of compressed data or cache pens that can be held in advance depends on the amount of RAM memory of the printer, the range of compressed data and cache pens to be held is reduced when the memory is small, depending on the installed memory. And expand the range of dynamic data creation according to the line width specification request.If sufficient memory is available, increase the range of compressed data and cache pen to be retained, and dynamically expand the data according to the line width specification request. It is necessary to have a structure that can be switched according to the situation, for example, by reducing the range in which the data is created.

However, in the above conventional example, pens to be cached in the pen step table in advance are limited to continuous data from the minimum line width to the maximum cache line width, and are newly created from compressed data or polypen data. The pen step data was always cached only once.

Therefore, when the amount of mounted RAM memory is small, if a certain amount of cache pens is provided, there is a possibility that a wide pen may not be developed, and the number of cache pens and the number of create pens to be cached are variably set. I needed to.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the first to seventh inventions according to the present invention to provide an apparatus for storing an area for storing a cash pen with a designated line width. By managing the create pen as an area for storing the create pen, the range in which the cache pen is held in advance and the range in which the create pen dynamically created according to the line width designation can be cached are freely changed to specify the designated line. An object of the present invention is to provide an output device capable of efficiently drawing a line having a width and a line segment drawing processing method of the output device.

[0027]

According to a first aspect of the present invention, there is provided a tilt based on a polyline obtained by dividing a circular arc having a radius corresponding to a predetermined line width into a predetermined number in line symmetry, and the center of the circular arc with respect to a vertex. Storage means for creating pen data having a set of directions and vertices coordinates, and storing pen step data obtained by adding predetermined management information to the created pen data; and storage means for storing the pen step data. A pen cache memory for reading the pen step data of the predetermined line width and temporarily storing the data as a pen, a designation unit for designating a desired line width, and a line width designated by the designation unit
Creating means for creating create pen data having a set of a slope based on a polyline obtained by dividing a circular arc having a radius corresponding to a predetermined number into a line symmetry, a direction from the center of the circular arc with respect to the vertex, and a coordinate of the vertex, Determining means for determining whether a cache pen having the line width specified by the means is cached in the pen cache memory; and determining that the cache pen having the specified line width is not cached in the pen cache memory. And a pen cache memory management means for clearing the pen step data already stored in the pen cache memory and storing the create pen data.

According to a second aspect of the present invention, the pen cache memory management means clears the pen step data already stored in the pen cache memory while updating the predetermined management information already stored, thereby creating the pen data. Is stored.

According to a third aspect of the present invention, a predetermined line width is set.
Pen data is created in which a set of the inclination, the direction from the center of the arc with respect to the vertex, and the coordinates of the vertex are set as a set based on a polyline obtained by dividing a circular arc having a corresponding radius into a predetermined number of lines symmetrically. Storage means for storing pen step data obtained by adding predetermined management information to the memory; a pen cache memory for reading out the pen step data of the predetermined line width stored in the storage means and temporarily storing the same as a cache pen; A line segment drawing processing method for an output device, comprising: a designation unit for designating a line width of a line; a slope based on a polyline obtained by dividing a circular arc having a radius corresponding to the line width designated by the designation unit into a predetermined number in line symmetry; A creating step of creating create pen data in which the direction from the center to the vertices and the coordinates of the vertices are a set, and a line specified by the specifying means Determining whether the pen is cached in the pen cache memory, and clearing the pen step data already stored in the pen cache memory to secure an area for registering the create pen data. Registering the create pen data in the pen cache memory; and updating the predetermined management information in the pen cache memory.

A fourth invention according to the present invention has a display means for displaying pen step data cached in a pen cache memory.

A fifth invention according to the present invention has printing means for printing pen step data cached in a pen cache memory.

A sixth invention according to the present invention has a display means for displaying pen step data cached in a pen cache memory.

A seventh invention according to the present invention has printing means for printing pen step data cached in a pen cache memory.

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on embodiments.

FIG. 1 is a schematic block diagram illustrating the configuration of an output device according to an embodiment of the present invention, and corresponds to a hardware configuration for implementing a pen data generation / management method for line drawing.

In the figure, 1 is a host computer,
The drawing command is sent to the printer 2. 3 is a CPU, RO
Each part is generally controlled based on a printer control program stored in M4 and control programs shown in FIGS. A RAM 6 is used as a pen cache memory area and a work area for the CPU 3.

Reference numeral 5 denotes pen data which stores pen step data having a predetermined width or pen step data obtained by compressing the pen step data. Reference numeral 7 denotes pen data, which stores pen step data as a pen cache or a create pen cache.

Hereinafter, this embodiment and the first, second, fourth, and fifth embodiments will be described.
The correspondence between the respective means of the present invention and the operation thereof will be described with reference to FIG.

According to a first aspect of the present invention, a set of a slope based on a polyline obtained by dividing a circular arc having the same radius representing a predetermined line width into a predetermined number in line symmetry, a direction from the center of the circular arc with respect to the vertex, and coordinates of the vertex are set as one set. Storage means (ROM 4) for storing pen step data obtained by adding predetermined management information to the generated pen data, and the pen having the predetermined line width stored in the storage means. A pen cache memory for reading step data and temporarily storing the data as a cache pen; a designating means (by command designation from the host computer 1) for designating a desired line width; and a pen having the same radius as the line width designated by the designating means. Create a set of inclinations based on polylines obtained by dividing a circular arc into a predetermined number of lines symmetrically, the direction from the center of the circular arc with respect to the vertex, and the coordinates of the vertex Creating means for creating a Ndeta (CP
U3 is created based on the program stored in the ROM4), and determining means (by the CPU 3) for determining whether or not the cache pen having the line width specified by the specifying means is cached in the pen cache memory.
When the determining means determines that the cache pen having the designated line width is not cached in the pen cache memory, the pen step data already stored in the pen cache memory is cleared and the create pen is cleared. A pen cache memory management means (by the CPU 3) for storing data,
Determines whether or not the cache pen having the line width designated by (1) is cached in the pen cache memory area of the RAM 6, when the CPU 3 determines that the cache pen having the designated line width is not cached in the pen cache memory. Then, the CPU 3 clears the pen step data already stored in the pen cache memory area and stores the create pen data, securely caches a new create pen in the pen cache memory area, and stores the new pen in the designated line width. Enables line drawing processing.

According to a second aspect of the present invention, the pen cache memory management means (by the CPU 3) clears the pen step data already stored in the pen cache memory while updating the predetermined management information already stored, thereby creating the pen data. Is stored, it is possible to read the pen step data of the designated line width from the pen cache memory even if the contents of the pen cache memory are rewritten.

In the fourth aspect of the present invention, a new create pen is securely cached in the pen cache memory area to perform a line drawing process with a designated line width, and a display means (shown in the drawing) is used by using the drawn create pen. LCD not
Display, FLC display, CRT, plasma display, etc.).

In the fifth aspect, a new create pen is securely cached in a pen cache memory area to perform a line drawing process with a designated line width, and a printing unit (printer) is used by using the drawn create pen. 2) It is possible to perform line drawing printing.

In this embodiment, a case where pen data is generated and managed in drawing a line with a maximum line width of 1000 will be described.

Here, RO as a pen data storage medium
M4 holds compressed data of pen data having a line width of “0” to “50”.

As described above, conventionally, in pen-step data approach processing, pen-step data has been stored continuously in the pen-step table C from the minimum line width to the maximum cache line width. The value of the line width thus obtained is the entry in the vertical pen step index table B of the horizontal pen step indexes A and B as it is.

In the present embodiment, since the pen step data is stored in the pen step table C in the order in which it was created, a pen ID table X is provided as shown in FIG.
Line widths are registered in the order in which they were created.

FIG. 2 is a view for explaining the data structure of the pen step of the polypen in the output device according to the present invention.
For example, the pen step of the polypen is stored in the RAM 6 shown in FIG.

In FIG. 2, a pen having a line width of 2 is registered as a third cached one with a pen ID of “3”. The pen step data corresponding to the line width designation command is retrieved from the index tables A and B by the pen ID.

Hereinafter, a pen cache method when a pen creation command is issued in the order of different line widths, for example, line width 10, line width 100, and line width 1000 will be described with reference to FIGS. 3, 4, and 5. I do.

FIG. 3 is a conceptual diagram for explaining the processing transition of the pen step data of the output device according to the present invention.

FIGS. 4 and 5 are flowcharts showing an embodiment of the pen step data processing method of the output device according to the present invention. Incidentally, (1) to (15), (3-1) to (3)
-3), (10-1) to (10-3), (11-1) to
(11-3) shows each step. [Processing Step of Selecting Pen with Line Width 10 at Program Initialization] In FIG. 3, when a pen with a line width W = 10 is requested (1), it is determined whether the line width W exceeds the maximum cache line width. Judge (2), if YES, step (3-
3) Proceed to shift, and if NO, search the pen ID table (3-1). Then, it is determined whether or not the pen is cached (3-2).
Proceed to 5).

In the example of FIG. 3, PENID [1] = NUL
Since nothing is registered in L, step (3-3)
Then, a pen having a width of 10 is newly registered as PENID [1] = 10.

Next, it is checked whether or not data of this width is held in the compressed data table in the ROM 6 (4).
~ (6). In this embodiment, since 10 <50 (the maximum width of the compressed data stored in advance), this data is extracted (7-2).

On the other hand, if NO in step (6), polypen data is created (7-1), and compressed data is created (8).

Next, the Free of Pen Step Table
By referring to the Index, it is checked whether there is enough free space for storing pen step data having a width of 10 (9), and it is determined whether there is enough free space in the pen step table (10-1). If YES, step (1)
Proceed to 0-3) and delete the required number of existing cash pens.

On the other hand, if NO in step (10-1), the number of existing cash pens to be deleted is calculated (10-
2) It is determined whether or not the number of registrations of the pen to be deleted exceeds the maximum registration number (11-1). If YES, the corresponding pen is excluded from the deletion target (11-3), and step (10-3). Return to).

On the other hand, if NO in step (11-1), the registration number of the pen to be deleted is incremented (11).
-2), proceed to step (10-3);

On the other hand, if it is determined in step (10-1) that the empty area is sufficient, a pen step and data are created from the extracted compressed data (12), and the pen step
Register it in the table (13).

Finally, the Pen step table Fre
The eIndex is advanced by the registered data, the position of the free area for registering the next pen is updated (14), a pen is selected (15), and the process is terminated. [Process for Creating a Pen with a Line Width of 100 During Execution of a Program] Hereinafter, a process for creating a pen with a line width of 100 during the execution of a program will be described with reference to FIGS.

FIG. 6 is a conceptual diagram for explaining the process transition of pen step data of the output device according to the present invention.

In FIG. 6, when a pen having a width of 100 is requested, the pen ID table is searched (3-1). In this embodiment, PENID [1] = 10, PENID [2] =
Since NULL is not cached for 100 pens (3-2), a pen having a width of 100 is assigned as PENID [2] = 10
Registered as 0 (3-3)).

Next, it is checked whether or not data of this width is held in the compressed data table in the ROM 4 (6). In the present embodiment, as shown in FIG. 6, since there is no compressed data corresponding to the width 100, (100> 5
0), and newly create polypen data and compressed data in this order (7-1), (8).

Next, the Free of Pen Step Table
Referring to the Index, it is checked whether there is enough free space to store the pen step data having a width of 100 (9). If it is determined that the free area still remains (10-2), pen step data is created from the created compressed data (12) and registered in the pen step table (13).

Finally, Fre of the pen step table
The eIndex is advanced by the registered data, the position of the free area for registering the next pen is updated (14), a pen is selected (15), and the process is terminated. [Process for Creating a Pen with a Line Width of 1000 During the Execution of a Program] The process for creating a pen with a line width of 1000 during the execution of a program will be described below with reference to FIGS.

FIG. 7 is a conceptual diagram for explaining the processing transition of pen step data of the output device according to the present invention.

In FIG. 7, when a pen having a width of 1000 is requested, the pen ID table is searched (3-1). In this embodiment, PENID [1] = 10, PENID [2]
= 100, PENID [3] = NULL, and a pen having a width of 1000 is not registered (3-2). In this embodiment, a pen having a width of 1000 is newly registered as PENID [3] = 1000 (3-3). .

Next, it is checked whether or not data of this width is held in the compressed data table in the ROM 4 (6). In this embodiment, since there is no compressed data corresponding to the width 1000 (1000> 50), a new polypen, data, and compressed data are created in this order (7-1).
(8).

Next, the Free of Pen Step Table
With reference to the Index, it is checked whether or not there is enough free space to store pen step data having a width of 1000 (10-1). In this case, it is determined that the free area is insufficient, and the amount of existing data to be deleted is calculated in order to register pen step data having a width of 1000 (10-).
2). Then, the necessary amount is deleted in order from the oldest one, that is, the one with the smallest pen ID (10-3).

Next, pen step data is created from the created compressed data (12) and registered in the pen step table (13).

Finally, the pen ID of the deleted pen is deleted, FreeIndex in the pen step table is updated (14), a pen is selected (15), and the process is terminated.

Hereinafter, the correspondence between this embodiment and each step of the third invention, and the sixth and seventh inventions, and the operation thereof will be described with reference to FIGS.

According to a third aspect of the present invention, a set of a tilt based on a polyline obtained by dividing a circular arc having the same radius representing a predetermined line width into a predetermined number in line symmetry, a direction from the center of the circular arc with respect to the vertex, and coordinates of the vertex are set as one set. Storage means (ROM 4) for storing pen step data obtained by adding predetermined management information to the generated pen data, and the pen having the predetermined line width stored in the storage means. A pen cache memory (RAM 6) for reading out step data and temporarily storing it as a cache pen, and a designating means for designating a desired line width (command designation by the host computer 1)
A line segment drawing processing method for an output device comprising: a slope based on a polyline obtained by dividing a circular arc having the same radius as the line width designated by the designation means into a predetermined number in a line-symmetrical manner; , A creation step of creating create pen data having a set of vertex coordinates as a set (pre-processing of step (1) in FIG. 4), and a cache pen having a line width designated by the designation means is cached in the pen cache memory. Determination step (step (3-1) in FIG. 4) for determining whether or not the pen step data already stored in the pen cache memory is cleared, and a clear step for securing an area for registering the create pen data. (Step (10-3) of FIG. 5 and a registration step of registering the create pen data in the pen cache memory (FIG. 5 Step (13)) and an updating step of updating the predetermined management information in the pen cache memory (Step (14) in FIG. 5) to reliably cache a new create pen in the pen cache memory area. Then, the line drawing processing of the designated line width can be executed programmably.

According to a sixth aspect of the present invention, a new create pen is securely cached in a pen cache memory area to perform a line drawing process of a designated line width, and a display means (shown in the drawing) is used by using the drawn create pen. LCD display, FLC display, CRT, plasma display, etc. which are not used) can automate the process of performing line drawing display.

According to a seventh aspect of the present invention, a new create pen is securely cached in a pen cache memory area to perform a line drawing process of a designated line width, and a printing unit (printer) is used by using the drawn create pen. 2) It is possible to automate the process of performing line drawing printing. [Other Embodiment 1] In the process of FIG.
From step (3-1) to step (3-1), the maximum cache line width information is added, that is, in step (1), the maximum line width of the registered cash pen is held as information, and (3) By adding step (2) to check if the requested pen line width does not exceed the maximum cache line width before entering, if the requested pen is larger than the maximum cache line width, Control may be performed so that the process can proceed to compressed data creation unconditionally.

In the above step (10-3), the number of times of registration / deletion for each line width is held, that is, information of the number of times of registration is added, and the pen registered for a certain number of times or more is added. In other words, by adding a process (11) to be excluded from the deletion target, if an existing cash pen is deleted by a new pen creation request, the one that is likely to be registered again in the future is stored. May be controlled as follows.

In the above embodiment, a printer was described as an example of an output device. However, it is needless to say that the present invention can be applied to a display that develops data to be output on a VRAM and displays and outputs the data.

[0084]

As described above, the first embodiment according to the present invention is described.
According to the invention, the determining unit that determines whether the cache pen having the line width specified by the specifying unit is cached in the pen cache memory stores the cache pen having the specified line width in the pen cache memory. When it is determined that the pen step memory is not present, the pen step data already stored in the pen cache memory is cleared and the create pen data is stored, so that a new line width is created in the pen cache memory area. The pen can be securely cached and the line drawing processing of the designated line width can be performed efficiently.

According to the second invention, the pen cache memory management means clears the pen step data already stored in the pen cache memory while updating the predetermined management information already stored, and stores the create pen data. Therefore, even if the contents of the pen cache memory are rewritten, the pen step data of the designated line width can be read from the pen cache memory.

In the third invention, it is determined whether or not the cache pen having the line width specified by the specifying means is cached in the pen cache memory, and the pen step data already stored in the pen cache memory is cleared. In this case, an area for registering the create pen data is secured, the create pen data is registered in the pen cache memory, and the predetermined management information in the pen cache memory is updated. Can be securely cached and the line drawing processing of the designated line width can be programmably executed.

According to the fourth aspect of the present invention, a new create pen is securely cached in the pen cache memory area to perform a line drawing process of a designated line width, and display means is provided by utilizing the drawn create pen. Can be displayed as a line drawing.

According to the fifth aspect of the present invention, a new create pen is securely cached in the pen cache memory area to perform a line drawing process of a designated line width, and the printing means is used by using the drawn create pen. Can perform line drawing printing.

According to the sixth aspect of the present invention, a new create pen is securely cached in the pen cache memory area to perform a line drawing process of a designated line width, and the display means is used by using the drawn create pen. The process of performing line drawing and display can be automated.

According to the seventh aspect of the present invention, a new create pen is securely cached in the pen cache memory area to perform a line drawing process of a designated line width, and the printing means is used by using the drawn create pen. The process of performing line drawing printing can be automated.

Therefore, the range in which the cache pen is held in advance and the range in which the create pen dynamically created according to the line width designation is cached can be freely changed, and the line drawing of the designated line width can be efficiently performed. And so on.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram illustrating a configuration of an output device according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a data structure of a pen step of a polypen in an output device according to the present invention.

FIG. 3 is a conceptual diagram illustrating a process transition of pen step data of the output device according to the present invention.

FIG. 4 is a flowchart showing one embodiment of a pen step data processing method of the output device according to the present invention.

FIG. 5 is a flowchart showing an embodiment of a pen step data processing method of the output device according to the present invention.

FIG. 6 is a conceptual diagram illustrating a process transition of pen step data of the output device according to the present invention.

FIG. 7 is a conceptual diagram illustrating a process transition of pen step data of the output device according to the present invention.

FIG. 8 is a diagram illustrating a pen step of a polypen in this type of output device.

FIG. 9 is a diagram illustrating a data structure of a pen step of a polypen in this type of output device.

FIG. 10 is a diagram illustrating a data structure of a pen step of a polypen in this type of output device.

FIG. 11 is a flowchart illustrating an example of a pen drawing processing procedure in this type of output device.

FIG. 12 is a diagram illustrating a drawing processing state in this type of output device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Host computer 2 Printer 3 CPU 4 ROM 5 Pen data 6 RAM 7 Pen data

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06T 1/00 G06T 11/00-17/50 G09G 1/00-5/42 G06F 3/00-3/153 B41J 5 / 00-5/52 B41J 21/00-21/18

Claims (7)

(57) [Claims] 1. A pen data having a set of a slope based on a polyline obtained by dividing a circular arc having a radius corresponding to a predetermined line width into a predetermined number in line symmetry, a direction from the center of the circular arc with respect to the vertex, and coordinates of the vertex. Storage means for creating and storing pen step data obtained by adding predetermined management information to the created pen data; and reading out the pen step data of the predetermined line width stored in the storage means to read and write the cache pen data. A pen cache memory for temporarily storing the data, a designating means for designating a desired line width, and a slope and a vertex based on a polyline obtained by dividing a circular arc having a radius corresponding to the line width designated by the designating means into a predetermined number in line symmetry. Generating means for generating create pen data in which the direction of the arc from the center of the arc and the coordinates of the vertices are a set, and a key having a line width specified by the specifying means. Determining means for determining whether or not a cache pen is cached in the pen cache memory; and determining that the cache pen having a designated line width is not cached in the pen cache memory. output apparatus characterized by comprising: a pen cache memory management means clear the pen step data already stored in the cache memory to store the Create pen data. 2. The pen cache memory management means clears the pen step data already stored in the pen cache memory and stores the created pen data while updating the predetermined management information already stored. The output device according to claim 1. 3. Creating pen data having a set of a slope based on a polyline obtained by dividing a circular arc having a radius corresponding to a predetermined line width into a predetermined number in a line-symmetric manner, a direction from the center of the circular arc with respect to the vertex, and the coordinates of the vertex. A storage unit for storing pen step data obtained by adding predetermined management information to the created pen data; and reading out the pen step data of the predetermined line width stored in the storage unit to form a pen as a cache pen. A line drawing processing method for an output device comprising a pen cache memory for temporarily storing and a designating means for designating a desired line width, wherein a predetermined number of arcs having a radius corresponding to the line width designated by the designating means are drawn. Creation step of creating create pen data having a set of the inclination based on the symmetrically divided polyline, the direction from the center of the arc with respect to the vertex, and the coordinates of the vertex. A determining step of determining whether a cache pen having the line width specified by the specifying unit is cached in the pen cache memory; and clearing the pen step data already stored in the pen cache memory to generate the create pen. wherein the clear step of reserving an area for registering the data, a registration step of registering the Create pen data to the pen cache memory, and updating step of updating the predetermined management information of said pen cache memory, that has a A line drawing processing method of the output device. 4. The output device according to claim 1, further comprising display means for displaying pen step data cached in the pen cache memory. 5. The output device according to claim 1, further comprising printing means for printing the pen step data cached in the pen cache memory. 6. A line segment drawing method according to claim 3, further comprising display means for displaying pen step data cached in the pen cache memory. 7. A line segment drawing method according to claim 3, further comprising printing means for printing the pen step data cached in the pen cache memory.