JP3145724B2 - Graphic data converter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphic data conversion apparatus, and more particularly to a graphic data conversion apparatus which can be used for a printing process using a computer.

[0002]

2. Description of the Related Art In recent years, computers have been actively used in the printing and plate making processes, and various image processing techniques using computers have been developed.
In particular, the creation of a picture combining geometric figures can be performed with a very simple operation by using a computer. Generally, a pattern that combines geometric figures
In the case of displaying on a display or the like, there is no problem even if the geometric figures are displayed as they are. However, when performing printing plate making based on such a pattern, the graphic data of the original geometric figure cannot be handled as it is.
This is because, when printing, it is necessary to treat each closed region constituting a picture as one unit, instead of treating the geometric figure itself as one unit.
For example, consider a pattern in which two circles partially overlap. If you want to display this pattern on the display,
What is necessary is just to display two circles overlapping. That is, it can be handled as a geometric figure called a circle. However, when this picture is printed, there are three closed areas: a closed area consisting only of the first circle, a closed area consisting only of the second circle, and a closed area where both circles overlap. Must be treated as Therefore, it is necessary to convert graphic data of a plurality of geometric figures into graphic data of a minimum constituent figure constituting a plurality of closed regions.

[0003]

A conventionally known graphic data conversion apparatus has a function of performing the above-described graphic data conversion. However, in the conventional device,
Since the conversion process is not completely automated, there is a problem that the conversion operation is troublesome and takes time. That is, the operator looks at the graphic pattern displayed on the display screen and uses a mouse or the like to move one of the closed regions into one.
A point is designated, and a process of recognizing a closed area including the designated point as a minimum constituent figure is performed. Therefore, it is necessary for the operator to manually give an instruction, and the operation becomes very troublesome. Further, since a so-called “painting algorithm” is used to recognize a closed area including the designated one point, a considerable time is required for the recognition processing.

Accordingly, an object of the present invention is to provide a graphic data conversion apparatus capable of automatically performing graphic data conversion processing in a short operation time.

[0005]

Means for Solving the Problems (1) The first invention of the present application newly generates graphic data of two geometric figures constituting a closed area by partially overlapping these two geometric figures. In a graphic data conversion device for converting graphic data of a minimum configuration graphic constituting a plurality of closed areas, a first storage area for storing graphic data before conversion,
A storage unit having a second storage area for storing the converted graphic data, a third storage area for storing data making up the table, and a storage unit based on the data in the first storage area. To recognize the intersection of two geometric figures,
An intersection recognition means for defining an intersection ID for the recognized intersection; and a line segment having both ends as the recognized intersection based on the data in the first storage area. And a line segment recognizing unit that defines a line segment ID including information for specifying a geometrical figure to which the line segment belongs, and a line segment recognized based on data in the first storage area. An internal / external determining means for determining whether the geometrical figure exists inside or outside the other geometrical figure that is not the geometrical figure to be given, and assigning the attribute “inside” or “outside” to this line segment, Table creation means for writing the line segment ID, intersection IDs corresponding to both end points of the line segment, and attributes given to the line segment as a table in the third storage area. Based on the table,
Only the line segment whose attribute is "inside" and the tracing has never been performed is traced so that the geometric figures to which it belongs belong alternately to form a closed area, and from this traced line segment The inner tracing means for writing the graphic data of the graphic as the converted graphic data in the second storage area, and based on the created table, the attributes are alternately changed, and the geometrical figures to which the figure belongs are alternately changed. In this manner, a closed area is formed by tracing a line segment for which the number of times of tracing has not expired, and writing the graphic data of a graphic composed of the traced line segment as converted graphic data in the second storage area. For each line segment, the number of times of tracing is counted, and for the line segment whose attribute is “inside”, the attribute is “outside” by two traces.
And a trace number counting means for indicating that the number of times of tracing for the line segment has expired by one tracing.

(2) The second invention of the present application is a method for constructing a plurality of closed areas newly generated by partially overlapping the plurality of geometric figures constituting the closed area with the plurality of geometric figures. A first storage area for storing graphic data before conversion, a second storage area for storing graphic data after conversion, A storage unit having a third storage area for storing data constituting the table; and a first storage area or a second storage area.
A target graphic extracting unit for extracting predetermined two graphic data as data of the target graphic, and based on the extracted data,
Recognize the intersection of two target figures, and add the intersection I to the recognized intersection.
An intersection recognizing means for defining D and a line segment having both ends as the recognized intersection based on the extracted data, and specifying the geometrical figure to which the line segment belongs to the recognized line segment. And a line segment recognition unit that defines a line segment ID including the information of the line segment, and based on the extracted data, the recognized line segment exists inside the other target graphic that is not the target graphic to which the line segment belongs. Inside / outside determining means for giving an attribute of “inside” or “outside” to this line segment, and, for all recognized line segments, the line segment ID and the end points of the line segment. A table creating means for writing the corresponding intersection ID and the attribute given to the line segment as a table in the third storage area; and based on the created table, the attribute is “inside” and the trace is Never been done The inner trace is formed by tracing only the minute portion so that the geometric figures to which it belongs belong alternately to form a closed area, and writing the figure data of the figure consisting of the traced line segments into the second storage area as the converted figure data. On the basis of the means and the created table, a closed area is formed by tracing a line segment whose number of times of tracing has not expired so that the attribute is alternately changed and the belonging graphic is alternately changed. Outer tracing means for writing the graphic data of the graphic consisting of the traced line segments into the second storage area as converted graphic data, counting the number of times of tracing for each line segment, and setting the attribute to "inside"
Is obtained by tracing twice, and the line segment having the attribute “outside” is obtained by one tracing.
Trace number counting means for indicating that the number of traces for the line segment has expired is provided, and the extraction work by the target figure extraction means and the processing on the extracted figures are stored in the second storage area as desired. This can be repeated until graphic data is obtained.

[0007]

[Operation] (1) In the graphic data conversion device according to the first invention of the present application, for two geometric figures overlapping each other, an intersection is recognized, and a line segment having the two intersections as end points is recognized. Are recognized as "inside" or "outside" of the other geometric figure, and a table is created based on these. Then, the minimum configuration graphic in which all sides are composed of line segments having the attribute “inside” and the minimum configuration graphic in which the line segment having the attribute “outside” is part of the side are separate procedures. Traced by Moreover, a line segment having the attribute “inside” has two traces, a line segment having the attribute “outside” has one trace,
Since the number of times of tracing is counted as in each case, when all the tracings are completed, all the minimum constituent figures are obtained.

(2) A graphic data conversion apparatus according to the second invention of the present application is such that the apparatus according to the first invention can be adapted to a plurality of geometric figures. The above-mentioned first
In the apparatus according to the invention of the present invention, data conversion for two geometric figures is possible. Therefore, if the operation of extracting data two by two from a plurality of geometric figures and performing data conversion is repeatedly performed, data conversion of a plurality of geometric figures becomes possible.

[0009]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a block diagram showing a basic configuration of a graphic data conversion device according to the present invention. This device includes a storage unit 1
0, target figure extracting means 20, intersection recognizing means 30, line segment recognizing means 40, inside / outside judging means 50, table creating means 6
0, inner tracing means 70, outer tracing means 80, and tracing number counting means 90. In practice, each of these components can be realized by a computer. That is, the storage means 10 is configured by a memory of a computer to be used or an external storage device, and each of the other components is configured by a processor operated by predetermined software.

[0010] The storage means 10 stores a first storage area 11 for storing graphic data before conversion, a second storage area 12 for storing graphic data after conversion, and data forming a table. And a third storage area 13. The target figure extracting means 20 extracts two predetermined figures as target figures from the figures stored in the first storage area 11 or the second storage area 12. The intersection recognizing means 30 recognizes the intersection of the two target graphics, the line segment recognizing means 40 recognizes the line segments constituting the two target graphics, and the inside / outside determining means 50 recognizes the "inside" of the recognized line segment. Alternatively, it has a function of giving an “outside” attribute. The table creating means 60 creates a table based on the recognized intersections, line segments, and attributes, and stores the table in the third storage area 13. The inner tracing means 70 and the outer tracing means 80 perform a line segment tracing process based on the table, create converted graphic data,
This is stored in the second storage area 12. The number of line segment tracing processes is counted by the tracing number counting unit 90. The above is the outline of the conversion processing by this device.

Subsequently, the conversion processing operation by this device is as follows:
A description will be given according to a specific example. Here, the conversion process for two geometric figures will be described first. Now, it is assumed that data on the graphic A and the graphic B as shown in FIG. 2 are stored in the first storage area 11. These graphic data may be prepared in any format. Usually, the coordinate values of four vertices for a rectangle such as the graphic A, and the coordinate values of the center point and the radius for the circle such as the graphic B are used. The values are prepared as graphic data. Here, a case is considered in which a picture is created by superimposing the two figures as shown in FIG. 3 and is used for printing. FIG.
As shown in FIG.
Two closed regions x, y, and z are newly generated. Therefore, as shown in FIG. 4, the minimum constituent figures of the picture are three figures X, Y, and Z. The purpose of this apparatus is to convert the two figures A and B shown in FIG. 2 to obtain three figures X, Y and Z shown in FIG. In other words, in the block diagram of FIG. 1, data of graphics X, Y, and Z are calculated based on graphics A and graphics B prepared in the first storage area 11,
The process of writing this in the second storage area 12 is performed. Hereinafter, the procedure of the conversion process will be described in detail.

First, the figure A and the figure B are extracted as the target figure by the target figure extracting means 20. The example described here is a process for a pattern composed of two figures, that is, a figure A and a figure B. However, as will be described later, when processing a pattern composed of three or more figures, Two predetermined figures are selected by the extracting means 20.

Subsequently, the intersection recognizing means 30 recognizes an intersection generated by partially overlapping the figure A and the figure B. In this example, as shown in FIG. 5, two intersections P and Q are recognized. Since the recognition of the intersection can be performed by a general geometric operation, a description of a specific operation method is omitted here. An intersection ID is defined for the recognized intersection. This intersection ID
May be any unique code that can identify the intersections. In this example, the names of the intersection “P” and the intersection “Q” are used as the intersection ID as they are.

When the intersection is recognized, the line segment recognition means 40 recognizes a line segment having the recognized intersection as both end points. In the case of this example, as shown in FIG. 5, the line segments a1, a2,
Four of b1 and b2 are recognized. In the drawing, different line types (solid line, dashed line, dashed-dotted line, two-dot dashed line) are shown so as to be distinguishable from each other. At this time, it is necessary to understand the matter to which graphic each recognized line segment belongs. For example, the line segments a1 and a2 are line segments belonging to the figure A, and the line segments b1 and b2 are line segments belonging to the figure B. Since a method for recognizing such a line segment is also known, a description of a specific calculation method is omitted here.

Next, in the inside / outside judgment means 50, an attribute is given to each recognized line segment. That is, an attribute indicating whether the line segment exists inside or outside the other figure that is not the figure to which the line segment belongs is given. For example, since the line segment a1 exists outside the figure B, the attribute "outside" is given, and the line segment a2 has the attribute "inside" because it exists inside the figure B. Further, the line segment b1 is provided outside the graphic A and therefore has the attribute “outside”, and the line segment b2 is provided inside the graphic A and thus “inside”.
Attribute is given. The determination of “inside” or “outside” may be made, for example, by the following method. That is, an arbitrary point is taken on the line segment to be determined,
Draw a ray from the point in any direction. If the number of times this half line intersects with the other figure is an even number (including 0), it can be determined as “outside”, and if it is an odd number, it can be determined as “inside”.

Subsequently, a table is created by the table creating means 60 and written into the third storage area 13. This table stores the line segment I obtained in each of the aforementioned steps.
D, intersection IDs corresponding to both end points of the line segment, and attributes given to the line segment are arranged in a table format. FIG.
In the example shown in FIG. 6, a table as shown in FIG. 6 is obtained.

When such a table is obtained, tracing is performed based on this table. Here, “trace” is an operation of sequentially tracing a plurality of line segments to form a figure surrounding one closed region. For example, in FIG. 5, by tracing the line segment b2 from the point P to the point Q and further tracing back the line segment a1 from the point Q to the point P, the figure X shown in FIG. 4 can be formed. Similarly, the line segment b2 is traced from the point P to the point Q, and further, the line segment a is moved from the point Q to the point P.
2 and return, the figure Y shown in FIG.
Tracing the line segment a2 from the point Q to the point Q, and further following the line segment b1 from the point Q to the point P, the figure Z shown in FIG. 4 can be formed. Eventually, in the example shown in FIG. 5, if tracing is performed along three routes, all three figures shown in FIG. 4 can be formed. Here, when the total number of times each of the line segments is traced in the trace by these three routes is examined, the line segments a1 and b1 are once and the line segments a2 and
b2 is two times. This is related to the attribute given to each line segment. That is, once for a line segment with the attribute “outside”, 2 for a line segment with “inside”.
This means that tracing has been performed a number of times. In other words,
If the line segment given the attribute “outside” is traced once and the line segment given “inside” is traced twice, the entire tracing work is completed. Trace count counting means 9
0 counts the number of traces performed for each line segment,
The line segment whose attribute is “inside” is indicated by two traces, and the line segment whose attribute is “outside” is indicated by one trace, indicating that the number of traces for the line segment has expired. . The actual tracing work is
Work by inner tracing means 70 and outer tracing means 8
The operation is performed in two stages, namely, the operation by 0. Hereinafter, these operations will be described in order.

The tracing operation performed by the inner tracing means 70 is for forming a minimum constituent figure composed only of line segments whose attribute is "inside". Therefore, only the line segment whose attribute is “inside” may be traced such that the geometrical figures to which the attribute belongs alternately change to form a closed region. Specifically, the following processing may be performed based on the created table. That is, an arbitrary line segment whose attribute is “inside” and tracing has never been performed is selected as a first line segment. A line segment satisfying the following four conditions is an i-th line segment. Choose as. Condition 1: the attribute is “inside” Condition 2: trace has never been performed Condition 3: belonging to a figure different from the figure to which the (i−1) th line segment belongs Condition 4: Two intersection IDs for the (i-1) th line segment
Have the same intersection ID as at least one of the above. Starting from i = 2, the process is repeated while increasing i one by one. However, if the i-th line segment has the same intersection ID as the intersection ID for the first line segment,
Then the work is completed.

In the example shown in FIG. 5, for example, the following tracing work is performed based on the table of FIG. First, the line segment a2 is selected as the first line segment, and then the line segment b
2 is selected as the second line segment, where the tracing work by this route is completed. By this tracing operation, the figure Y in FIG. 4 is formed. The inner tracing means 70 attempts to perform a tracing operation by another route, but the tracing satisfying the above conditions can no longer be performed. This is because the line segments a2 and b2 have already been traced once, and therefore do not satisfy the condition of “a line segment that has never been traced”. This is because there is no "inside" line segment. Thus, the inner tracing means 70 completes the mission by tracing only by this one route.

The subsequent tracing operation by the outer tracing means 80 is for forming a minimum constituent figure in which a line segment having the attribute "outside" is a part of a side. To do this, make sure that the attributes alternate, and
It is only necessary to sequentially trace the line segments whose number of times of tracing has not expired so that the graphics to which they belong alternately. Specifically, the following processing may be performed based on the created table. That is, an arbitrary line segment whose trace count has not expired is selected as the first line segment.

A line segment satisfying the following four conditions is selected as the i-th line segment. That is, condition 1: the number of traces has not expired condition 2: having an attribute different from that of the (i-1) th line segment condition 3: the figure to which the (i-1) th line segment belongs Belonging to different figures Condition 4: Two intersection IDs for the (i-1) th line segment
Have the same intersection ID as at least one of the above. Starting from i = 2, the process is repeated while increasing i one by one. However, if the i-th line segment has the same intersection ID as the intersection ID for the first line segment,
Then the work is completed.

In the example shown in FIG. 5, for example, the following tracing work is performed based on the table of FIG. First, the line segment a1 is selected as the first line segment, and then the line segment b
2 (as described above, tracing is performed once by the tracing work of the inner tracing means 70, but the attribute is “inside”, so the number of times of tracing expires twice) is selected as the second line segment. The tracing work by this route is completed there. By this tracing operation, the figure X of FIG. 4 is formed. Outer tracing means 80
Attempts to perform a tracing operation by another route. For example, the line segment a2 is selected as the first line segment, and then the line segment b1 is selected as the second line segment, where the tracing operation by this route is completed. By this tracing operation, the figure Z of FIG. 4 is formed. The outer tracing means 80 attempts to perform a tracing operation by another route, but the tracing satisfying the above conditions can no longer be performed. Because, at this point, all the line segments have already completed the number of times of tracing. Thus, the outer tracing means 80 completes the mission by tracing by two routes.

In this way, 1 by the inner tracing means 70
The figure Y in FIG. 4 is formed by the trace of the route, and the figures X and Z of FIG. 4 are formed by the trace of the two routes by the outer tracing means 80, and these figure data are written in the second storage area 12. As a result, the data of the figures X, Y, and Z are obtained in the second storage area 12 based on the data of the figures A and B prepared in the first storage area 11.

Although the conversion procedure for two partially overlapping figures has been described above, the apparatus of the present invention can perform conversion even when three or more figures overlap. Now, for example, consider a pattern in which three figures C, D, and E overlap as shown in FIG. In this pattern, a total of seven closed areas are generated, so three graphic data must be converted into seven graphic data. In such a case, two graphics may be extracted as target graphics, and the above-described conversion operation may be repeatedly performed. Specifically, the following processing is performed. First, graphic data of three graphics C, D, and E are prepared in the first storage area 11. The target figure extracting means 20 extracts two of them, for example, figures D and E, as target figures. The conversion procedure for the two figures D and E is as described above. As shown in FIG. 8, the closed areas i, j, and k are generated by the figures D and E, and the minimum constituent figures I, J, and K are obtained in the second storage area 12. Therefore, the original proposition "Finding the smallest constituent figure for three figures C, D, and E" can be replaced with the proposition "Find the smallest constituent figure for four figures C, I, J, and K". it can. Therefore, the target graphic extracting means 20 extracts the graphic C from the first storage area 11 and the graphic I from the second storage area 12, respectively, as target graphics.
Then, as shown in FIG. 9 (a), the conversion procedure for finding the minimum constituent figure for figures C and I is performed as described above. Further, as shown in FIG. 9 (b), the minimum constituent figure for figures C and J is obtained, and as shown in FIG. 9 (c), the minimum constituent figure for figures C and K is obtained. In the second storage area 12, seven minimum constituent figures for three figures C, D, and E are obtained. As described above, by repeatedly performing the operation of always extracting two target graphics and obtaining the minimum constituent graphics, conversion processing of three or more graphics can be performed.

Although the basic operation of the apparatus of the present invention has been described above, special exception processing needs to be prepared in order to enable application to any figure. For example, as shown in FIG.
Is located on one side of the other figure F, or as shown in FIG. 10B, the side h1 (point H1
In this case, a side having the end point of H2 and H2) overlaps one side of the other figure F, exception processing needs to be performed on the basic operation described above. The case shown in FIG.
In the case shown in FIG. 10B, the exceptional processing for the case shown in FIG. 10B will be described here because it can be handled as a special case where the end points H1 and H2 match. In this case, as shown in FIG. 11, four intersections H1, H2, H3, and H4 are recognized, and four line segments h1, h2, h3, and h4 are recognized as lines belonging to the graphic H. As a line segment belonging to the figure F, four line segments f
1, h1, f2, f3 are recognized. What matters here is how to handle the line segment h1. The line segment h1 belongs to both figures. In this case, the attribute "inside" is given to the line segment h1, but the exception is handled such that the number of times of tracing expires once. In this case, the line h
The route of 1, h2, f3, h4 is traced,
A closed area g1 as shown in FIG. 12 is formed. At this time, the number of traces of the line segment h1 is exceptionally expired. Following the trace by the outer trace means 80, the line segment f
Traces of a route 1, h2, a route f3, h3, and a route f2, h4 are performed, respectively.
The closed areas g2, g3, g4 as shown in FIG. 12 are formed.

As shown in FIG. 13, when the L-shaped figures L1 and L2 overlap each other, the area M is surrounded by a figure and is substantially a closed area. However, the conversion by the present apparatus does not become the minimum constituent figure. This is because the attributes of the line segments m1 and m2 are "outside" and only one trace is performed. Therefore, the finally obtained minimum configuration graphic is only the closed area portion hatched in the figure.

As an application of the present invention, for example, FIG.
It is also possible to obtain a maximum constituent figure W as shown in FIG. 15 based on three figures V1, V2 and V3 as shown in FIG. This can be done by always selecting a line segment whose attribute is "outside" and selecting a line segment belonging to another figure. If such a maximum constituent figure W is obtained, a figure slightly larger and a figure slightly smaller than this can be easily created, and is highly useful in performing printing plate making.

Although the present invention has been described based on the illustrated embodiment, the present invention is not limited to this embodiment, but can be implemented in various other modes. For example, in the above-described embodiment, an example using a relatively simple geometric figure is shown. However, in practice, the present invention effectively works on a complicated geometric figure composed of a free curve such as a cloud. Further, in the above-described embodiment, the line segments constituting each figure are treated as geometrically pure line segments having no width. It is common to construct figures. Therefore, in practice, it is necessary to handle such that the joints between the sides of each figure have the same coordinates within the allowable width.

[0029]

As described above, according to the graphic data conversion apparatus of the present invention, the attribute is defined for each line segment constituting the graphic, and tracing is performed according to a predetermined algorithm. The operation of converting the data of the geometrical figure into the data of the minimum constituent figure can be performed automatically and in a relatively short operation time.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a graphic data conversion device according to the present invention.

FIG. 2 is a diagram showing an example of two figures before conversion prepared in a first storage area 11 of the apparatus shown in FIG.

FIG. 3 is a diagram showing a closed region generated by partially overlapping two figures shown in FIG. 2;

FIG. 4 is a diagram showing an example of a figure after conversion written in a second storage area 12 of the device shown in FIG. 1;

FIG. 5 is a diagram showing intersections and line segments recognized for the two figures shown in FIG. 2;

FIG. 6 is a diagram showing a table created based on the two figures shown in FIG. 2;

FIG. 7 is a diagram showing three figures before conversion prepared in a first storage area 11 of the apparatus shown in FIG. 1;

FIG. 8 is a diagram showing three closed regions generated by two of the three graphics shown in FIG. 7;

FIG. 9 is a diagram showing each figure constituting the three closed regions shown in FIG.
FIG. 8 is a diagram showing a closed region generated by another figure shown in FIG. 7.

FIG. 10 is a diagram showing a graphic pattern that requires exception processing in the device shown in FIG. 1;

FIG. 11 is a diagram showing intersections and line segments recognized for the graphic shown in FIG. 10;

FIG. 12 is a diagram showing four closed regions generated by the graphic shown in FIG. 10;

FIG. 13 is a diagram showing another graphic pattern to be converted by the apparatus shown in FIG. 1;

FIG. 14 is a diagram showing a graphic pattern to be processed by the apparatus shown in FIG. 1 to obtain a maximum constituent graphic.

FIG. 15 is a diagram showing a maximum constituent figure obtained based on the figure shown in FIG. 14;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Storage means 11 ... 1st storage area (save figure data before conversion) 12 ... 2nd storage area (save figure data after conversion) 13 ... 3rd storage area (save table) 20 ... Object figure extracting means 30 Intersection recognizing means 40 Line segment recognizing means 50 Inner / outer judging means 60 Table creating means 70 Inner tracing means 80 Outer tracing means 90 Trace number counting means A to K, L1, L2, V1 ~ V3, W, X, Y, Z ... figure M ... closed area G1, H1, H2, H3, H4, P, Q ... intersections a1, a2, b1, b2, f1-f3, h1-h4, m
1, m2 ... line segment g1 to g4, i, j, k, x, y, z ... closed region

Claims (2)

(57) [Claims] 1. The graphic data of two geometric figures forming a closed area are converted into graphic data of a minimum constituent figure newly forming a plurality of closed areas by partially overlapping the two geometric figures. A graphic data conversion device for converting, comprising: a first storage area for storing graphic data before conversion, a second storage area for storing graphic data after conversion, and data forming a table. A storage unit having a third storage area for saving, and an intersection of two geometric figures is recognized based on data in the first storage area, and an intersection ID is defined for the recognized intersection. An intersection recognizing means for recognizing a line segment having both ends as the recognized intersection based on the data in the first storage area, and identifying a geometric figure to which the line segment belongs to the recognized line segment Segment I containing information to perform A line segment recognizing means for defining D, and a line segment recognized based on the data in the first storage area is present inside another geometric figure which is not the geometric figure to which the line segment belongs; Inside / outside judging means for judging whether the line segment exists or outside the line segment and giving an attribute of “inside” or “outside” to the line segment, for all recognized line segments, the line segment ID, and both end points of the line segment Table creation means for writing, as a table, the intersection ID corresponding to the intersection point and the attribute given to the line segment in the third storage area, and based on the table, the attribute is "inside" and the trace Only the line segments that have never been performed are traced so that the geometric figures to which they belong alternately form a closed area, and the figure data of the figure consisting of the traced line segments is converted to the converted figure data. As the second An inner trace means for writing into the storage area, in accordance with the table,
Trace the line segments whose number of times of tracing has not expired to form a closed area so that the attribute changes alternately and the geometric figures to which they belong alternately, and form a closed area. Outer tracing means for writing graphic data as converted graphic data in the second storage area; counting the number of times tracing has been performed for each line segment; A trace number counting means for indicating, by a single trace, that the number of traces for each of the line segments whose attribute is “outside” has expired by a trace. Data converter. 2. The graphic data of a plurality of geometric figures constituting a closed area are converted into graphic data of a minimum constituent figure constituting a plurality of newly formed closed areas by partially overlapping the plurality of geometric figures. A graphic data conversion device for converting, comprising: a first storage area for storing graphic data before conversion, a second storage area for storing graphic data after conversion, and data forming a table. Storage means having a third storage area for saving, and target graphic extraction means for extracting two predetermined graphic data as data of a target graphic from the first storage area or the second storage area An intersection recognizing means for recognizing an intersection of two target graphics based on the extracted data and defining an intersection ID for the recognized intersection; A line segment recognition means for recognizing a line segment to be a point, defining a line segment ID including information for specifying a geometric figure to which the line segment belongs to the recognized line segment; Based on this, it is determined whether the recognized line segment exists inside or outside the other target figure that is not the target figure to which this line segment belongs. Inside and outside judging means for giving the attribute of each of the recognized line segments, their line segment IDs, intersection IDs corresponding to both end points of the line segments, and attributes given to the line segments as a table. And a table creation means for writing into the storage area of No. 3 and, based on the table, only the line segments whose attributes are “inside” and whose tracing has never been performed are alternately assigned to the geometrical figures to which they belong. Trace to change and closed area Inner tracing means for writing the graphic data of the graphic consisting of the traced line segments into the second storage area as the converted graphic data; and changing the attributes based on the table so that the attributes belong to each other. A line segment whose number of times of tracing has not expired is traced to form a closed area so that the target figure to be alternated alternately, and the figure data of the figure consisting of the traced line segment is used as the converted figure data as the second figure data.
Outside tracing means for writing to the storage area of each line segment, and counting the number of times tracing is performed for each line segment. For the line segment whose attribute is "inside", the line segment whose attribute is "outside" is obtained by tracing twice. Trace number counting means for indicating that the number of times of tracing for the line segment has expired by one tracing,
Graphic data conversion, wherein the extraction work by the target graphic extracting means and the processing on the extracted graphic can be repeatedly performed until desired graphic data is obtained in the second storage area. apparatus.