JP2870397B2 - How to fill the drawing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for filling a drawing, and more particularly to a method for filling a drawing of a polygonal figure.

[0002]

2. Description of the Related Art Conventionally, a polygonal figure is filled by selecting an aperture prepared for filling the figure or an object having a maximum diameter from a pen, and the aperture or the portion which cannot be filled with the pen is selected from the following. I replaced the aperture or pen with a smaller one and filled it.

FIG. 2 shows a flowchart.

First, in a process 13, polygon data is read from the CAD data. Of the polygonal data,
Only the outer shape data is extracted in processing 14. Next, the offset line creation processing 15 will be described.

First, an aperture (or pen) table related to processes 15, 19, and 20 is created. Aperture (or pen) table is a CAD containing multiple polygons
It may be prepared every time data is processed, or a fixed table may be prepared in advance. Aperture (or pen)
The table shows the size of the aperture (or pen), a code that can distinguish the aperture (or pen),
Information such as color is provided, and the images are arranged in order from the largest one based on the size of the aperture (or pen). Since the number of arrays corresponds to the number of apertures (or pens), the number is stored. Table 1 shows an example of the aperture (or pen) table.

[0006]

[Table 1]

Each array is provided with information such as an aperture diameter, a color, and a code (aperture name). The array numbers are given to know the number of apertures. Here, it is stored that there are eight arrays. The aperture to be used is determined based on the size. In the following description,
For simplicity, only the aperture is used, and only the required color is black. In practice, a code is required, but a description of the process of filling a figure is omitted because a code is not particularly necessary. (In the case of a pen, it is clear that there is no problem even if the aperture and the pen are replaced.) After creating the aperture table (or from a fixed table, from that table), select and offset the aperture from the first array element An offset line is created with the amount being the radius of the aperture and the offset direction being inward with respect to the outer shape. An example is shown in FIG. An offset line segment 22 is created with the distance of the radius of the aperture kept from the contour 21, and connection information (or data configuration) of the segment of the contour 21 is created.
Thus, the effective portion of the line segment 22 is connected to obtain the offset line 23.

Next, in step 16, the effective range of the offset line is determined. First, since the offset line forms a loop that can be drawn with one stroke, it is checked whether a self-intersection exists. If not, all of the offset lines are valid. If there is a self-intersection, split the offset line by the intersection to form a new loop. However, at this time, the direction of the line segment forming each loop is stored. It is checked whether each loop has a clockwise configuration or a counterclockwise configuration, and a loop having the same configuration as the external configuration is set as an effective range. In the example of FIG.
Is clockwise. The self-intersections 25 and 26 divide the offset line 23 into three loops. In this example, only the loop sandwiched between the self-intersections 25 and 26 is counterclockwise and is deleted. The remaining two loops are the effective range of the offset line.

Next, in decision 17, the first processing 16
Immediately after is always no.

Next, in processing 18, a hatching line is created to fill the area closed by the effective offset line. The hatching pitch is the diameter of the aperture used in the immediately preceding process 15 (practically, it is better to set the diameter of the aperture minus the permissible error in consideration of machine errors). Although the hatching direction is arbitrary, it is general to minimize the total extension of the line segment. Before creating the hatching line, an offset line is calculated using the radius of the aperture used for hatching as an offset amount, and it is confirmed whether or not the effective range of the offset line exists. In the example of FIG. 3, a hatching line is not created when this check is performed. (No need to do this.) Next, in decision 19, it is checked whether there is a smaller aperture.
If the aperture table in Table 1 is checked, it can be seen that there is an available aperture, so the answer is yes. By reducing the aperture, the outline of the polygon can be filled with higher precision. Further, in the example of FIG. 3, since the deleted portion has not yet been filled, the aperture can be reduced by reducing the aperture. However, a portion that cannot be filled with the smallest aperture becomes an error when the polygon is filled.

In step 20, the aperture is reduced and the offset amount and aperture code are changed.
Then, the second process 15 is performed. The process is repeated until there is no more aperture.

In the flowchart of FIG. 2, the hatching line is created only once, but in order to realize this, the diameter of the aperture should be reduced to less than 50% at the stage of reducing the diameter of the aperture. No. Table 1 as an example
If there is no array number 3 in the aperture table, the aperture is reduced by one step in the processing 20 in FIG. At this time, a hatching line is required if a portion that could not be filled with the first aperture is to be filled with an aperture having a size of 25%. In FIG. 4, the offset line 27 is the locus of the first aperture, and the offset line 28 is the locus of the aperture having a size of 25%. The circles 29 and 30 represent the image of the size of each aperture, and it can be seen that hatching lines are required in the hatched portions 31.

The polygon has been filled in the above procedure.

Japanese Patent Application Laid-Open No. 64-44580 discloses a method related to the crushing method in this kind of CAD / CAM.
Japanese Unexamined Patent Application Publication No. 2-51779 discloses a technique related to offset line creation using a CAD system .

[0015]

In the prior art, in the process of reducing the size of the aperture (or pen) and filling in, the offset line is created even in the portion that has already been filled, so that the aperture (or pen) is created. Or the total length of the trajectory of the pen increases. Also, prepared apertures (or pens created for each process)
Polygons smaller than the smallest aperture (or pen) in the table cannot be filled and must be deleted, but until the iteration uses the smallest aperture (or pen), There is waste in the calculation process.

The offset line creation method has not been solved, for example, in the case of a polygon having a plurality of contours, or in the case where offset lines which cannot be determined by the closed loop directionality of the offset lines overlap. There is.

[0017]

[SUMMARY OF] To solve the above problems, in the method for filling the drawings of the invention are, (1) calculate
Load the figure data created by the
Means for extracting the shape data and reading it into the storage means;
(2) multiple contour lines belonging to polygon data
Means for calculating the inclusion relation level of the data, and (3) the contour
Means for calculating the difference between inside and outside of the closed area of the line data; (4)
Calculate the direction to offset line data of contour data
And (5) transferring the line segment data in the offset direction.
Means for calculating and storing offset line data;
(6) Check the intersection and overlap of the form represented by the offset line data.
It has a means for discriminating and overlapping polygonal areas
Create and output line segment data to fill without
Have .

[0018]

First, a plurality of outlines of a polygon are ranked as level 1 , level 2,. Similarly, by assigning a level to each offset line, the relationship between loops having different levels can be determined.

Since the offset amount is determined by selecting the aperture (or pen) table in order from the first, the table is created so that the table with the smaller diameter can be used.
Thus, in the first determination, a polygon smaller than the size that can be filled can be easily deleted.

When the process of creating the offset line is repeated, a portion where the actual trajectory of the aperture (or pen) overlaps appears. By deleting this portion, the total length of the line necessary for filling can be shortened. I can do it.

By applying the above processing, the problem can be solved.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below.

FIG. 1 shows a flowchart of the present invention. The input 1 reads polygon data.

Next, in process 2, all contours of the polygon are extracted. Specifically, since the contour line is a closed loop, the connection relationship of the line segment data is checked to determine how many loops are formed. In the example of FIG. 5, three loops of the contour lines 32 and 33 are found.

Next, in process 3, the contours are ranked. There is no connection relation between contour lines, and only an inclusion relation exists. Therefore, the maximum value and the minimum value of the X direction component and the maximum value and the minimum value of the Y direction component of the absolute coordinate values of the elements constituting each contour are obtained for each contour, and the inclusion relation is determined from the magnitude relation. Assuming that the outline is a level 1 outline, the outline included in the outline is a level 2 outline. Level 2
The contour line included in the contour line is set to level 3. In this way, the contour lines are ranked by assigning levels to the contour lines based on the inclusion relation. Next, the direction of the contour line is determined. The level 1 contour may be clockwise or counterclockwise. However, the contour lines of level 2 and thereafter are in the opposite direction to the contour lines of the next higher level.
In FIG. 5, the contour 32 is at level 1 and the contour 33 (the number of loops 2) is at level 2. The direction of the loop of the contour line of each level is clockwise at level 1 and counterclockwise at level 2.

Next, in process 4, an offset line is created. The offset direction is determined by the level of each contour line. Offset to the area closed by the contour line at the odd number level. At an even number level, offset outside the area closed by the contour. After determining the offset direction,
Offset the contour line by line segment. The offset amount is determined according to an aperture (or pen) table prepared for filling the polygon. Table 1
However, in the case of the present invention, the offsets are used in ascending order of the diameter, and the offset amount is １ ／ of the diameter.

The offset line segments are connected at intersections so as to maintain the connection of the outline lines. If the offset lines of the segments connected on the contour line do not have an intersection, they are connected by an arc. This will be described with reference to the example of FIG. Outline segment 36, 37, 3
8 has a connection relationship, and the direction of the contour line is clockwise. Each line segment obtained by offsetting the contour line segment is indicated by a broken line. A line segment obtained by offsetting the contour lines 36 and 37 has an intersection 39. Accordingly, the line segments offset at the intersection 39 are connected. Next, the line segments obtained by offsetting the contour lines 37 and 38 have no intersection, so they are connected by an arc 40. The center of the arc 40 is set as the end point of the contour line segment 37 or the start point of the contour line segment 38.
In this way, the line segments obtained by offsetting the adjacent contour lines are connected to create an offset line. At this time, the offset line inherits the direction and level of the contour line.

When an arc is included in the configuration of the contour line, the offset direction is on the side of the area including the center coordinate of the arc, and when the offset amount is larger than the radius of the arc, the data of the arc must be deleted. is there. This will be described with reference to the example of FIG. Since the offset line is a line that is equidistant from the contour line,
When the arc is offset, as shown in FIGS. 7A and 7B, the offset line 43 with respect to the arc 41 is
Is a part of a concentric circle having the center 42 as the center coordinate. At this time, in FIG. 7A, since the offset direction is opposite to the side where the center coordinates of the arc are located, it is not necessary to consider the offset amount. However, in the example of FIG. 7B, since the offset direction is on the side where the center coordinate of the arc is located, if the offset amount is larger than the radius of the arc, the calculation is easier if the arc data is deleted. If an offset line is created with an offset amount larger than the radius of the arc, it will be as shown by a dashed line 44 in FIG. 7C, but this is a story on the drawing. The computer attempts to create an arc whose radius is the value obtained by subtracting the offset amount from the radius of the arc, but in the example of FIG. 7C, the computer has a negative radius, which makes the determination complicated. Become. Further, as can be seen from the example of FIG.
Are always deleted in the determination of the direction of the loop . Therefore, there is no problem even if the offset line is created ignoring the arc data from the beginning.

Next, in process 5, the effective range of the offset line is determined, and a new contour line is created. The effective range is determined in order from level 1. However, since the effective ranges may interfere (intersect) with each other, every time the effective range of a set of offset lines of odd and even levels that may cause interference (intersection) is determined, the interference of the offset lines (intersection) is determined. Intersection)
Is determined. The effective range determined by the determination is set as a new contour line of each level.

Next, a method of determining the effective range will be described. First, it is checked whether a self-intersection exists in the level 1 offset line. If there were no self-intersections, the level 1 offset lines would all be in scope. If there is a self-intersection, split the offset line at the intersection. However, when the segments of the offset line overlap, they do not intersect and do not divide the offset line. The offset line is
Although it is one loop, the number of loops increases due to division. Each of the divided loops is determined to be valid if its direction is the same as the direction of the level 1 contour, and is deleted as invalid if it is in the opposite direction. In the example of FIG. 8A, the loop is divided at the intersections 45 and 46 with respect to the offset line indicated by the broken line, and the loops 47 and 48 that are the effective range are obtained. Thus, the effective range of the level 1 offset line is determined.

Next, the effective range of the level 2 offset line is determined. First, check whether a self-intersection exists. This processing is the same as in level 1. Next, it is necessary to check the interference (intersection) between the offset lines of the same level as the processing after the level 2. In this case, loop reconnection is performed at an intersection. From an arbitrary line segment of an arbitrary one of the closed loops of the plurality of offset lines, the line is traced in the direction of the own loop, and connected to a closed loop other than the own at an intersection. At this time, the connection to the closed loop other than itself is maintained in the direction. By continuing this until returning to the first line segment, a new closed loop is obtained.

Next, the first selected arbitrary loop is traced from the first intersection, and a closed loop is similarly obtained. This is continued until all the components of each loop before the division are used. This will be described with reference to the example of FIG. In the figure, the offset lines of the level 1 outline 49 are omitted for simplicity.
First, an offset line indicated by a broken line is created for the contour line 50 of level 2. If the user follows an arbitrary line segment of one of the left and right loops, it will hit either the intersection 51 or 52. Therefore, the connection of the loop is changed while maintaining the direction of the loop (here, counterclockwise). If this operation is continued until an arbitrary line segment is selected, a closed loop 53 or 54 is obtained. Next, when the loop selected first among the left and right loops is traced from the first one of the intersections 51 and 52, the closed loops 53 and 5 are obtained.
Of the four, those other than those previously obtained are obtained.

When the reconnection of the closed loop is completed, the inclusion relation of each closed loop is examined. The determination of the inclusion relation may be performed by obtaining the maximum and minimum X and Y direction components and comparing them in the same manner as in the ranking in the process 3. Thus, the outermost loop is set as the level 2 offset line effective range.
Next, the loop direction is checked for the loops included in the outermost loop (if there are a plurality of loops, all of them). If the direction is the same as the level 2 contour line, it is deleted. If there is a reverse direction, this loop is also the effective range of the offset line. In the example of FIG. 8B, the closed loop 54 is deleted.

Here, the interference (intersection) and the inclusion relation in the effective range of the offset lines of level 1 and level 2 are examined. Considering an offset for filling a figure, there is a possibility of interference (intersection) between offset lines when the order of levels is odd and even. First, check whether interference (crossing) exists. Level 1 if there is no interference (crossing)
Then, it is checked whether the inclusion relation of the offset effective range of level 2 is the same as the inclusion relation of each contour line. When the inclusion relation is the same, both offset lines are finally effective, and when reversed, both offset lines are deleted.
In the example of FIG. 5, the level 1 offset line 34 and the level 2
Since there is no interference (intersection) and there is no inversion in the inclusion relationship, the offset lines 35 become new contour lines. If the inclusion relationship is reversed, no offset line will be created, but this polygon is considered to be an error that may be deleted from the data because it is below the aperture (or pen) accuracy. If there is interference (intersection), split the loop at the intersection. The division method is the same as in the case where there is interference (intersection) between offset lines at the same level. Following the level 1 offset line loop segment, at the intersection with the level 2 offset line loop, reconnect so that the direction of the loop is maintained, and connect to the first selected line segment of the level 1 offset line. Following this, the effective range is determined. The judgment method is that if the direction of the divided loop is the same as the level 1 contour line, it is valid, and if it is the opposite direction, it is invalid and deleted. In the example of FIG. 9, after changing the loop between the level 1 offset line 55 and the level 2 offset line 56 at the intersection, the effective range 57 is obtained from the new loop direction.

With respect to the offset lines with respect to the level 2 and level 3 contour lines, since the offset directions are away from each other, it is not necessary to examine the interference (intersection) and the inclusion relation. In general, when filling the figure, when the offset line levels are even and odd,
It does not check for interference (intersection) or inclusion. It is necessary to examine the case where the levels of the offset lines are in an odd-numbered, even-numbered order (1, 2, 3, 4,...).

In this processing 5, interference (intersection) was checked to determine the effective range. If two loops share a line segment (part or all of the line segment elements overlap)
In this case, it is assumed that this is not an intersection and that the loop is not divided. Thus, an aperture (or pen) that can trace on the overlapped line segment must use the offset amount as a radius. This is the basis for increasing the offset amount in the subsequent processing by two times.

Next, it is checked in decision 6 whether processing 5 has passed the first time. At the first time, processing 7 is executed.
At the second and subsequent times, the process 8 is executed.

In processing 7, the offset amount is made the same as the first time. That is, when viewed from the first contour, the distance is twice as long as the first time. This is because, when the first offset line is the trajectory of the aperture (or pen), the outline of the area filled with the aperture (or pen) is used as the next offset line. Thus, when the offset line is repeatedly created, it is not necessary to determine the already filled area. In addition, there is no remaining paint. For example, description will be made with reference to the example of FIG. When a trajectory for filling the rectangle in the figure with the aperture 58 is created, the trajectory becomes like a broken line. In order to fill the area 59 that could not be filled with the aperture 58, in the present invention, the outline of the area 59 is used as an offset line, and the offset line is traced with an aperture twice as large as the aperture 58. If you make the aperture larger than twice, then all offset lines will be invalid,
The region 59 may be left unpainted. In this case, the number of processes such as creating a hatching line by reducing the aperture increases, and the efficiency becomes poor. Therefore, it is efficient to increase the offset amount by two times. However, in the actual processing, the next offset line is calculated using the offset line as a new contour line, so that the offset amount for the first time is 径 of the diameter of the aperture, but the offset amount for the second and subsequent times is the aperture amount of the aperture. 1/4 of the diameter. That is, the reason why the second offset amount is the same as the first offset amount is that, by doubling the diameter and further １ ／, the result is オ フ セ ッ ト of the aperture diameter.

Thereafter, the processings 3, 4, and 5 are executed, and a judgment 6 is made.
Therefore, the judgment 9 is executed.

In judgment 9, it is checked whether or not the polygon is completely filled. In process 5, when a new contour line has not been created and the condition that the offset line is created for the second time or later is satisfied, it can be determined that the filling has been completed.

In process 8, a process for shortening the total extension of the trajectory of the aperture necessary for filling is performed. First, the second offset line is left as a new contour line.

Next, the offset line for the second time is offset to the outside of the area closed by the closed loop for the odd number level, and to the inside of the area closed by the closed loop for the even number level.
That is, the offset is performed in the direction opposite to the offset direction in the process 4. The offset amount is the same as in the processing 4. Here, most of the offset line overlaps with the first offset line, so the duplicated line segment is deleted. Thereby, the total extension of the offset line becomes shorter. But,
Since the data amount increases, when the data amount is prioritized, the process 8 may be performed without performing the process 8. The data amount is increased simply because one line segment is divided into two line segments. A description will be given by taking, as examples, (a), (b), (c), and (d) of FIG.
In FIG. 11A, a level 1 offset line 60 and a level 2 offset line 61 are created for the outlines 64 and 65. FIG. 11B shows the offset line 6 in FIG.
A second offset line is created by setting 0, 61 as a new contour line. This second offset line 62
When the process 8 is performed on the, the dashed line 63 in FIG. 11C is obtained. The dashed line 63 is subtracted from the first offset lines 60 and 61 in FIG.
FIG. 11D shows the remaining portion of 1. By obtaining FIG. 11D, the process 8 ends.

In the third and subsequent times, the difference between the line offset in the direction opposite to the process 4 and the previous offset line is calculated to update the previous offset line.

In the judgment 10, while counting the number of times the offset line is created, it is checked whether the offset line has reached an arbitrary set value. If not reached, the offset amount is doubled in processing 11 and the processing moves to processing 3. If the set value has been reached, process 12 is executed.

In process 12, a hatching line is created.
The aperture (or pen) used for hatching should be the same as the one used to create the last offset line. The hatching pitch is slightly smaller than the aperture (or pen) coating width. This is because an error in the operation of the drawing machine or the plotter is considered. The pitch is obtained by subtracting an error from four times the last offset amount.
Next, a method for creating hatching will be described. The hatching direction is defined as a 0 degree direction when the hatching line is parallel to the X axis, and a 90 degree direction when the hatching line is parallel to the Y axis. Here, for the sake of simplicity, the description will be made assuming that the hatching directions are only 0 degrees and 90 degrees.

First, the maximum and minimum values of the X-direction component and the maximum and minimum values of the Y-direction component are obtained from the new contour line data. Next, the difference between the maximum value and the minimum value of the X and Y direction components is calculated, and the difference between the X direction and the Y direction is compared. At this time,
Even if there are a plurality of level 1 contours, the maximum and minimum are determined by considering one loop (contour) for convenience. This calculation is performed only for odd-level contour lines. Because the rectangular area surrounded by the maximum value and the minimum value is the minimum area for virtually creating hatching,
Since the contour lines of the even-numbered levels are always included in the odd-numbered levels, there is no need to make a determination.

In this virtual rectangle, one set of diagonal coordinates is X
The coordinates of the maximum value in both the direction and the Y direction, and the coordinates of the minimum value in both the X and Y directions. By comparing the difference between the maximum value and the minimum value of the components in the X and Y directions in the X and Y directions, it is checked which of the axes of the long sides X and Y of this rectangle is parallel. If parallel to the X axis, the hatched line at 0 degree
If parallel to the axis, create a 90 degree hatch line.

In the following, consideration will be made with reference to a rectangle for forming a hatching line in the 0-degree direction. Since the hatching line is parallel to the X axis, the hatching line is determined by the Y coordinate. Hatching pitch Y from maximum or minimum value of Y coordinate
Create hatched lines inside the rectangle by shifting the coordinates. Next, hatching lines outside the area closed by the level 1 contour are deleted. If there is no contour line after level 2 inside the area closed by the contour line of level 1, the processing 12 is terminated, and when there is a contour line of level 2 or later, the higher level is prioritized. , The hatching line included in the region closed by the even-numbered outline is deleted, and the hatching line included in the region closed by the odd-numbered outline is left. Specifically, the hatching line is traced from the smaller X coordinate to the larger one. When the contour line of level 1 is hit, the hatching line up to that point is deleted, and the hatching line is traced to level 1 or level 2. Then, the hatched line is divided into two at the second intersection, leaving a line on the left side of the intersection. Follow the line on the right. Further, when the object hits the contour, the line segment up to that point is deleted. This is performed until the X coordinate on the hatched line reaches the maximum value. When the X coordinate reaches the maximum value, the last line segment is also deleted. At this time, an intersection (contact) at only one point is not treated as an intersection. Also, when the line segment of the contour line overlaps the hatching line, there is no intersection. In order to realize this using a computer, the intersection between one hatched line and all contour lines is calculated. At this time, contact and overlap with the outline are ignored. The obtained intersections are rearranged in ascending order of the X coordinate to form an array. The odd-numbered array start point, the even-numbered array end point,
By creating line segments in order from the first, hatching lines are created to fill the contour lines. This may be applied to each hatched line.

Next, processing in the 90-degree direction will be described.
First, all the contour lines included in the virtual rectangle are rotated 90 degrees around the point where the coordinate values X and Y components are both 0, that is, the origin of CAD data including a plurality of polygons. The rotation at this time is the same as the rotation of the coordinates in mathematics, and is a rotation with the counterclockwise direction being a positive direction.
By doing so, Ru can be the calculation of hatching the process of creating a hatch line of 0 degrees direction exactly the same. After finding the hatching lines, set each hatching line around the origin-
By rotating by 90 degrees, a hatching line in the direction of 90 degrees can be obtained.

Although the creation of hatching lines at 0 ° and 90 ° has been described above, hatching lines in any direction (angle) can be created based on 0 °. First, all the outlines are rotated, then a virtual rectangle is calculated, a temporary hatching line is created inside the rectangle, and the same processing as at 0 degrees may be performed. Thereafter, the hatching line is rotated back and returned. The virtual rectangle when creating a 90-degree hatch line is
Since the rotation calculated from the contour before rotation and the rotation calculated from the contour after rotation are the same, there is no need to calculate twice, so the rotation is performed together with the contour.

FIG. 12A shows a virtual rectangle 66. FIG. 12B shows intersections A, B, C, D, E, and F of the hatching line and the contour line, and the lines having the odd-numbered start point and the even-numbered end point in ascending order of the X coordinate. This indicates that the minute is a required hatching line.

In the hatching line creation processing, the polygon filling is completed.

[0053]

As described above, according to the present invention, in the method of filling a drawing, a polygonal contour having a plurality of contours is ranked and each interference (intersection) is determined. Complex polygons with multiple outlines can be filled.

Also, by using an aperture (or pen) with the smallest diameter, a polygon having a precision or less can be found and deleted by the shortest processing, thereby shortening the processing time by a computer such as a CAD. it can.

Further, by doubling the aperture (or pen) and increasing the aperture (or pen) used for the hatching line, the data amount and the total length of the solid line can be reduced. When the area is doubled, by removing the overlapped portion from the previous offset line, there is an effect that the total extension of the filled line can be further reduced.

[Brief description of the drawings]

FIG. 1 is a flowchart of the present invention.

FIG. 2 is a flowchart of a conventional example.

FIG. 3 is a conceptual diagram of a conventional offset line creation.

FIG. 4 is a diagram of a conventional example in which hatching is required twice.

FIG. 5 is an image diagram of creating an offset line according to the present invention.

FIG. 6 is an image diagram showing a case where offset lines have no intersection and are connected by an arc.

7 (a), (b) and (c) show a case where the contour has an arc.

FIG. 8A is a diagram illustrating an effective range determination based on a self-intersection of a level 1 offset line. FIG. 6B is a diagram of the effective range determination based on the interference (intersection) point of the level 2 offset line.

FIG. 9 is a diagram illustrating an effective range determination based on an interference (intersection) point between offset lines of level 1 and level 2;

FIG. 10 is a diagram showing a problem when the aperture (or pen) is made larger than twice.

FIG. 11 is a diagram showing a method of removing overlapping portions of offset lines in a series of (a), (b), (c), and (d).

FIG. 12A is a diagram of a virtual rectangle in a hatching creation diagram. (B) A diagram of a hatched line segment.

[Explanation of symbols]

 1 Data input unit 2 Contour extraction processing 3 Ranking processing 4 Offset line creation processing 5 Contour update processing 6 Judgment (1st processing) 7 Offset amount change processing 8 Duplicate line deletion processing 9 Judgment (completed) 10 Judgment (whether the processing has been performed the specified number of times) 11 Offset amount change processing 12 Hatch processing 13 Data input unit 14 Data extraction processing 15 Offset line creation processing 16 Effective range determination processing 17 Judgment (whether hatching) 18 Hatching processing 19 Judgment (Aperture is present) 20 Processing to reduce aperture 21 Outline line 22 Offset line 23 Offset line 24 Loop direction 25 Self-intersection 26 Self-intersection 27 Offset line (first time) 28 Offset line (second time) 29 Aperture image ( Second time) 30 aperture images ( 32) Level 1 contour line 33 Level 2 contour line 34 Level 1 offset line 35 Level 2 offset line 36 Level 1 contour line 37 Level 1 contour line 38 Level 1 contour Contour line 39 Intersection point of offset line 40 Interpolated arc 41 Arc part of contour 42 Center of arc 43 Arc line of offset line 44 Offset line including temporary arc 45 Self-intersection point of offset line 46 Self-intersection point of offset line 47 Offset line effective loop 48 Offset line effective loop 49 Level 1 outline 50 Level 2 outline 51 Intersection of level 2 offset line 52 Intersection of level 2 offset line 53 Offset line (closed loop) 54 Offset line (closed loop) 55 Level 1 offset line 56 levels Offset line 57 offset effective range 58 aperture 59 area that cannot be painted with aperture 58 60 level 1 offset line 61 level 2 offset line 62 offset line effective range (second time) 63 reverse offset line 64 level 1 contour 65 level 2 Outline 66 virtual rectangle

Claims (1)

(57) [Claims] 1. A read into the storage means of the computer graphics data created by CAD, the computer process, (1) the storage means extracting storage means a polygonal contour line data from among the graphic data stored in the maximum and storing, (2) in its contour data, when the contour line data belonging to one polygon there are a plurality of X-direction component of the absolute coordinate values of the elements constituting the plurality of contour lines Value, maximum
The small value and the maximum and minimum values of the Y-direction component are calculated for each contour line.
The maximum and minimum values of the components of the absolute coordinate value.
By calculating the relation, the inclusion relation is calculated, and the envelope data
Calculate the level value representing the order of the implicit relationship, and link the level value
And storing in the storage means in addition to Guo line data, (3) level value (hereinafter referred to as the offset line data) line data to keep the contour line data phrase certain distance which stores the offset direction direction (hereinafter to create a (4) calculating the inside or outside of the area closed by the contour line and storing it in the storage means ; and (4) offset line data obtained by adding the minimum offset amount in the offset direction to the contour line data. Calculate and write to storage
A step of 憶, (5) the effective range of the offset line data created intersection of the self-intersection and other offset line data of the offset line data, calculated by the conditions of the overlap, the effective portion of the offset line data <br/> The closed loop data formed by
And storing the extracted storage means from the data, (6) the (5) a closed loop data as new contour data calculated by the offset amount relative to the first contour line data of the polygon first previous as two times the offset amount, the (2), (3), (4), and performing the step of (5), after step (7) above (6), in step (6) In the direction opposite to the offset direction, offset line data is created and recorded using the offset amount as the difference between the offset amount in the step (6) and the absolute value of the offset amount one time before.
By storing the data in the storage unit and comparing it with the previous contour data , the data of the overlapping portion is deleted from the previous contour data and stored , and the data necessary for filling the polygon is stored. Contour line day
A step of reducing the motor, (8) the (6), number of repetitions steps of any (7), in the area closed by the latest outline data, that a step of creating a hatching data Characteristic drawing method.