JPH1115985A - Plotting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To plot a high definition line graphic by forming a graphic which includes a point that moves an outer connection point of rectangular graphics toward a rectangular graphic only by small distance and a point which moves a connection point of linear segments in the expanding direction of an angle that includes a segment in-between by small distance as vertexes. SOLUTION: A coordinate point group of a rectangular graphic that is calculated by a rectangular forming part is a point (d), a point (e), a point (f) and a point (g) about a rectangular graphic 11, and is points (h), (i), (j) and (k) about a rectangular graphic 12. Also, about a connection graphic 13 that is calculated by a joint graphic forming part, it is points (d'), (m), (h') and (b'). In such cases, a graphic is formed which includes a point that moves an outer connection point of rectangular graphics toward a rectangular graphic only by small distance and a point which moves a connection point of linear segments in the expanding direction of an angle that includes a segment in-between by small distance as vertexes. Because the sought connection graphic 13 has overlapping parts to the graphics 11 and 12, there is no gap at connecting side parts between itself and the graphics 11 and 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drawing apparatus which receives line segment data and draws a line figure having a predetermined width, and more particularly to a drawing apparatus which can draw a line figure having a bent portion. is there.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open No. 6-168339 discloses a technique for drawing a connected group of line segments having a fixed width (that is, a polygonal line).
No. 6,086,045. In this document, a continuous line is drawn by drawing a short line in a rectangle and giving a wedge-shaped or fan-shaped figure as a connection figure to a break point connecting the short lines. This technique is used not only for drawing a straight line group but also for drawing a curve by a minute straight line.

When a polygonal line is drawn by the above technique,
In rare cases, the wire may be broken at the bent portion. FIG.
FIG. 4 is an explanatory diagram of an example of a problem in a conventional drawing apparatus. In the figure, 11 and 12 are rectangles, and 13 is a connection figure.
In FIG. 5, a rectangle 11 is a line segment ab drawn with a width W, and a rectangle 12 is a line segment cb drawn with a width W. The line segment ab and the line segment cb are connected at a point b, and the point b is called a connection point. A rectangle 11 formed by width of the line segment ab by the width W is represented by
Have points d and d ′, which are moved by W / 2 in opposite directions to each other in the direction of the normal line. Similarly, a rectangle 12 formed by dividing the line segment c-b by the width W has a point e obtained by moving the point b by W / 2 in directions opposite to each other in the normal direction of the line segment c-b. , E ′ at the vertices. Note that points d and e
Are called outer connection points, and points d 'and e' are called inner connection points.

[0004] If the rectangles 11 and 12 are merely drawn, they are not continuous at the connection points d and e outside the connection point b. Therefore, the connection graphic 13 is drawn by the technique described in the above-mentioned literature. . The figures drawn in FIG. 5 in this manner are rectangles 11, rectangles 12, and connection figures 13 at the bent portions.

The problem here is that the line segment dd 'or the line segment e-
e '(or both) is not necessarily guaranteed to pass through point b, which was the calculation starting point. Therefore, a point b ′, which is one of the vertices of the connection graphic 13 (this is the original connection point b of the line segment), does not coincide with the intersection b of the rectangles 11 and 12. Further, at that time, if the point b 'is located outside the rectangle 11 or the rectangle 12, an unintended gap is generated between the rectangle 11 or the rectangle 12 and the connection graphic 13.

Furthermore, even if these coordinate point calculations have sufficient accuracy and the point b and the point b 'are calculated to have substantially the same coordinate value, these coordinate data are used. Depending on the specifications of the figure filling device, there is a possibility that a gap of 1 dot may be left between the contacting sides and the sides (the same side).

FIG. 6 is an explanatory diagram of an example of a solution to the problem in the conventional drawing apparatus. As a simple countermeasure against the above-described problem, there is a drawing method in which each line segment is drawn long by a minute amount ε. FIG. 6 shows an example of a figure drawn by such a drawing method. In FIG. 6, hatched portions are portions drawn by extending each line segment by a small amount ε.

By using such a drawing method, the part where the connection graphic 13 was drawn is certainly filled. However, the portion drawn here by extension extends beyond the area to be filled as the angle between the line segments approaches horizontal (180 degrees). For example, point d in FIG.
In addition, the vicinity of the point e protrudes outward, and there is a problem that an unnecessary projection-like figure is generated.

On the other hand, as another technique for filling the gap of a line segment at a connecting portion between a straight line and a curved line or a curved line and a curved line, for example, JP-A-8-263671 and JP-A-8-2636.
As disclosed in Japanese Patent Publication No. 72-72, there is also a technique for eliminating a gap between a curve and a straight line, that is, a gap in which a connected figure is to be drawn, by aligning the tangent directions of a connecting portion between the straight line and the curve. However, this technique does not eliminate a gap generated around a connection graphic for interpolating between a line segment and another line segment. For example, even in the above-mentioned literature, cracks between minute straight lines constituting a curve are filled in by an interpolation unit, but it is not suggested that a void is generated around the filled connection graphic,
There is no solution.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and is capable of drawing a connecting line group having a line width with high quality without generating a gap at a connection point. It is intended to provide a device.

[0011]

According to a first aspect of the present invention, as the connection graphic, a point obtained by moving the outer joint point of the rectangular graphic by a small distance to the rectangular graphic side and a connection point of a straight line segment. A figure is formed which includes, as vertices, a point moved by a small distance in the direction in which the line segment scissor angle spreads. Since the drawing area is calculated so that the formed connection graphic overlaps the rectangular figure by a very small distance, even if an error occurs, no gap is generated. In addition, the gap at the time of filling is filled.

According to a second aspect of the present invention, when a rectangular figure is formed, the side inside the bent portion of the straight line segment is formed to be elongated by a minute distance. In addition, when forming the connection graphic, the outer joint point of the rectangular graphic is formed as a graphic including at its vertices a point moved a small distance toward the rectangular graphic.
In this way, by increasing the drawing area of both the rectangular figure and the connection figure by a small area and overlapping them, even if a calculation error occurs, it is filled with the overlapped drawing area and no gap is generated. Further, by extending only the inner side of the rectangular figure, the projection as shown in FIG. 6 does not occur. In addition, voids during filling are filled.

According to a third aspect of the present invention, in forming a rectangular figure, two end points of a straight line segment and four points obtained by moving each of the two points by half the line width in the normal direction of the straight line. A total of 6
The rectangular figure (strictly, a hexagon) constituted by points is formed. As shown in FIG. 5, since the gap between the rectangular figure and the connection figure was a calculation error at the connection point of the straight line segment, the connection point which is one of the vertices of the connection figure is used to form the rectangular figure. If they are included as vertices, the effects of calculation errors can be completely eliminated. As a result, no gap is generated due to a calculation error.

[0014]

FIG. 1 is a basic configuration diagram showing one embodiment of a drawing apparatus according to the present invention. In the figure, reference numeral 1 denotes a rectangle forming unit, and 2 denotes a joint figure forming unit. The values of the coordinate points of at least two lines to be given a line width (that is, three points for two lines) and the value of the line width W are passed to the rectangle forming unit 1. The rectangle forming unit 1 calculates the coordinates of the four vertices of the rectangular figure which is the basic figure constituting each line segment, one set for each line segment. The joint figure forming unit 2 calculates a vertex group of a connected figure for smoothly connecting the two rectangular figures. The coordinate point group of the rectangular graphic and the connected graphic calculated in this way is stored as it is, for example, or drawn on the output device via a paint processing unit (not shown).

The rectangular figure 1 or the joint figure forming unit 2 or the rectangular figure 1 and the joint figure forming unit 2 cooperate with each other so that no void is generated between the rectangular figure and the connected figure. The coordinate group of the coordinate group or the connected figure, or the coordinate group of the rectangular figure and the connected figure is calculated. Hereinafter, some of these specific calculation methods will be described.

FIG. 2 is an explanatory diagram of a first operation example in the embodiment of the drawing apparatus of the present invention. FIG. 2 shows a line segment a
The drawing illustrates a case in which −b and a line segment bc are connected at a point b and drawn with a width W. The coordinate points of the rectangular figure obtained by the rectangular forming unit 1 are points d, e,
Points f and g, and points h, i, j and k for the rectangular figure 12. Also, the joint figure forming unit 2
Are the points d ′, m, h ′, and b ′. Each configuration method will be described below in order.

First, in the rectangle forming section 1, a rectangular figure 11
A method of configuring a coordinate point group of the rectangular graphic 12 will be described. A unit vector Eab having the direction of the line segment ab
Ask for. Assuming that the vector of the line segment ab is Vab, the unit vector Eab is Eab = Vab / | Vab |. Here, | V | represents the length of the vector V. The same applies hereinafter.

From the unit vector Eab, the unit vector Eab
The normal unit vectors EOab and EOab ′ of ab are obtained. The normal unit vector EOab is the unit vector Ea
b is rotated by π / 2 counterclockwise, and the normal unit vector EOab ′ is a unit vector obtained by rotating the unit vector Eab by π / 2 clockwise. That is, when Eab = (x, y), EOab = (− y, x) and EOab ′ = (y, −x).

From the obtained normal unit vectors EOab and EOab ′, normal unit vectors EOab and EOab
displacement vector EOWab, EOW obtained by multiplying ab 'by W / 2
Find ab '. That is, the displacement vector EOWab,
EOWab 'is: EOWab = (W / 2) .EOab EOWab' = (W / 2) .EOab '. Assuming that the position vector of the point b is OVb, the points represented by the vectors OVd and OVe calculated by OVd = OVb + EOWab OVe = OVb + EOWab 'are points d and e in FIG.

Similarly, a displacement vector EOWab,
Points moved by the action of EOWab 'are points g and f. The above four points, that is, the point d, the point e, the point f, and the point g form the rectangular figure 11. Regarding the rectangular figure 12, four points, that is, points h, i, j, and k can be obtained from the line segment bc in exactly the same manner as described above.

Next, a method for forming a group of coordinate points of the connecting graphic 13 in the joint graphic forming section 2 will be described.
First, a point d ′ obtained by moving the point d in the opposite direction of the vector Vab by a small amount ε is obtained. That is, it is obtained as OVd ′ = OVd−ε · Eab. Here, OVd and OVd ′ are position vectors from the coordinate origin to points d and d ′, respectively, and ε is a predetermined constant. Similarly, a point h ′ obtained by moving the point h by a small amount ε in the direction of the vector Vbc.
Ask for. The vector Vbc is a displacement vector of the line segment bc. Note that the constant ε may be any value as long as it is equal to or less than the line segment length. However, since it is difficult to know the shortest line segment length in advance, it may be determined, for example, about 1/10 of the line width W.

Next, the vertex m of the break point is obtained. Using the unit vectors Eab and Ecb in the direction of the line segment ab and the line segment cb, the position vector OVm to the point m is obtained as follows: OVm = OVb + {W / (2 sin θ)} · (Eab +
Ecb). Here, OVb is the position vector of point b, and θ is the angle between Eab and Ecb. Where si
nθ can be easily calculated by the cross product of the vectors Eab and Ecb.

Next, a point b 'obtained by moving the point b by a small amount ε is obtained by the following equation. OVb ′ = OVb−ε · (Eab + Ecb) The four points obtained in this way, that is, the points d ′, m,
A rectangle connecting the points h ′ and b ′ is the connection graphic 13.

As described above, by the coordinate calculation in the rectangle forming unit 1 and the joint figure forming unit 2, the coordinate points forming the rectangular figure 11, the rectangular figure 12, and the connection figure 13 can be obtained. Connection figure 13 found
Has an overlapping portion with respect to the rectangular graphic 11 and the rectangular graphic 12, so that no gap is generated at the connection side portion between the connecting graphic 13 and the rectangular graphic 11 and the rectangular graphic 12. Also,
Even if there is a possibility that there is a gap of one dot between sides that are in contact with each other due to the specifications of the filling process or the like, there is no gap due to the overlapping portion.

FIG. 3 is an explanatory diagram of a second operation example in the embodiment of the drawing apparatus of the present invention. In this example, a method is shown in which a joint figure is deformed by a very small amount in the joint figure forming unit 2 and a rectangular figure formed by the rectangle forming unit 1 is also deformed to eliminate the gap between the rectangular figure and the connecting figure. I have.

In this example, the rectangular figures 11 and 12 formed by the rectangular forming section 1 are trapezoids. A method of configuring these trapezoidal coordinate groups will be described. First, a unit vector Eab having the direction of the line segment ab is obtained. If the vector of the line segment ab is Vab, the unit vector Ea
b is Eab = Vab / | Vab |. Next, a normal unit vector EOab and EOab ′ of the unit vector Eab are obtained. The normal unit vector EOab is obtained by dividing the unit vector Eab counterclockwise by π / 2.
Rotated normal vector EOab '
Is obtained by rotating the unit vector Eab clockwise by π / 2. That is, if Eab = (x, y), EOab = (− y, x) and EOab ′ = (y, −x). Next, the normal unit vectors EOab and EOa
displacement vectors EOWab, EOWa obtained by multiplying b ′ by W / 2
Find b '. Displacement vectors EOWab, EOWab '
EOWab = (w / 2) · EOab EOWab ′ = (w / 2) · EOab ′ The points obtained by adding these displacement vectors to the point b are the points d and e.

Here, the point e is further moved by a small amount δ in the direction of the vector Eab. Assuming that the position vectors of the point e and the moved point e ′ are OVe and OVe ′, respectively, the position vector OVe ′ is OVe ′ = OVe + δ · Eab. Here, δ is the movement amount of the point e, and can be set arbitrarily. For example, similarly to the minute amount ε in the first operation example, it may be set to about 1/10 of the line width.

On the other hand, the point a is defined as a displacement vector EOWab, E
Points g and f are moved by OWab '. The above four points, that is, the point d, the point e ′, the point f, and the point g constitute a coordinate group of the trapezoidal rectangular figure 11. The trapezoidal rectangular figure 12 can be calculated in exactly the same way. The four points h, i, j, and k ′, which is obtained by moving the point k by a small amount δ in the direction of the vector Ecb. Thus, a coordinate group of the trapezoidal rectangular figure 12 is formed.

Next, a method of forming a coordinate group of the connection graphic 13 in the joint graphic formation unit 2 will be described.
The connection graphic 13 in this example is a graphic composed of four points d ', m, h', and b. First, a point d ′ obtained by moving the point d in the opposite direction of Vab by a small amount ε is obtained. That is, it is obtained as OVd ′ = OVd−ε · Eab. Here, OVd and OVd ′ are position vectors from the origin to points d and d ′, respectively, and ε is a predetermined constant and can be set arbitrarily. As in the first operation example, the line width W is also 1 /
It can be set to about 10. Also, the rectangular forming part 1
Is not necessarily the same value.
Similarly to the point d ′, the point h is shifted by a small amount ε in the vector Vbc direction.
The point h 'moved by the distance is obtained. Next, a vertex m is obtained. Using the unit vectors Eab and Ecb in the line segment ab and the line segment cb direction, the position vector Vm to the point m is
It is obtained by the following equation. Vm = OVb + {W / (2 sin θ)} · (Eab + E
cb) where OVb is the position vector of point b and θ is the vector E
The angle between ab and Ecb. By the above coordinate calculation, four coordinates constituting the connection graphic 13, that is, the points d ′, m, h ′, and b can be obtained.

In this manner, a polygonal line having a width can be drawn by the three figures of the trapezoidal rectangular figure 11 and the rectangular figure 12 obtained by the rectangle forming unit 1 and the connection figure 13 obtained by the joint figure forming unit 2. . At this time, as shown by hatching in FIG. 3, a triangle dee-e 'which is a part of the rectangular figure 11, a triangle hkk' which is a part of the rectangular figure 12, and a Triangle b- which is a part
dd 'and the triangle bhhh' overlap with other figures.
For this reason, it is possible to eliminate the occurrence of voids at the connection between each rectangular figure and the connection figure.

In the example shown in FIG. 3, the inside connection point of each rectangular figure is shifted out of the rectangular figure, and the vertices corresponding to the outside connection points among the vertices of the connected figure are shifted into the rectangular figure. However, the present invention is not limited to this. For example, the outside connection point of each rectangular figure may be shifted to the outside of the rectangular figure, and the connection point of the connection figure may be shifted to the open side of the line segment. However, in this case, depending on the size of the minute amount ε, when the outer joint point is shifted, FIG.
Therefore, it is necessary to set the minute amount ε so that such a problem does not occur.

FIG. 4 is an explanatory diagram of a third operation example in the embodiment of the drawing apparatus of the present invention. Also in this example, the line segment ab and the line segment bc are connected at the point b,
It is assumed that the image is drawn with the width W. Point d, point e, point f, point g forming the rectangular figure 11, point h, point i, point j, point k forming the rectangular figure 12, and one of the connecting figures 13
The method of calculating the point m, which is one vertex, is the same as in the above-described first operation example, and a description thereof will not be repeated. The other vertices of the connection graphic 13 share the points d, b, and h of the rectangular graphic 11 and the rectangular graphic 12. If drawing is performed as it is, rectangular figures 11 and 12 and connection figures 13
There was a possibility that a gap might be formed at the connection portion with.

In this example, the rectangular figure formed by the rectangular forming section 1 is composed of six points instead of four points. That is, the rectangular graphic 11 shown in FIG. 4 is generated as a rectangle (exactly, a hexagon) composed of points d, b, e, f, a, and g. Similarly, the rectangular figure 12 has points h, i, c,
It is configured as a hexagon of points j, k and b. Note that the connection graphic 13 is configured as a quadrangle of points d, m, h, and b.

According to this method, since the point b in the connection graphic 13 is exactly the same as the vertices of the rectangular graphic 11 and the rectangular graphic 12, a numerical calculation error does not occur in principle. The same applies to points d and h. Therefore, the generation of voids due to numerical calculation errors can be completely eliminated.

However, the possibility of a gap of about one dot occurring between the same sides due to the above-described specification of the figure filling device or the like is not excluded only in the third operation example. Therefore, if it is known that the figure filling apparatus has the possibility, for example, the first operation example or the second operation example described above is performed.
By using the operation example (2) together, it is possible to realize a drawing in which no gap is completely generated. In this case, the minute amount ε may be extremely small (a distance corresponding to one dot).

In each of the above-described operation examples, a case has been described in which a line drawing is performed by a so-called miter connection in which a connected figure has a sharp vertex. Other types of line segments include, for example, those connecting outer connection points (for example, points d and h in FIG. 4) with straight lines, or connecting them with arcs or curves. However, since the connection type has no relation to the problem of eliminating the gaps on the line segment db and the line segment dh, even when using other connection types, the above-described respective examples are completely eliminated. The same applies.

[0037]

As is apparent from the above description, according to the present invention, even when a line figure having a very precise and wide width is drawn, no crack (gap) is formed at the bending point of the straight line. There is an effect that it is possible to draw no high-quality line figures.

[Brief description of the drawings]

FIG. 1 is a basic configuration diagram illustrating an embodiment of a drawing apparatus according to the present invention.

FIG. 2 is an explanatory diagram of a first operation example in the embodiment of the drawing apparatus of the present invention.

FIG. 3 is an explanatory diagram of a second operation example in the embodiment of the drawing apparatus of the present invention.

FIG. 4 is an explanatory diagram of a third operation example in the embodiment of the drawing apparatus of the present invention.

FIG. 5 is an explanatory diagram of an example of a problem in a conventional drawing apparatus.

FIG. 6 is an explanatory diagram of an example of a solution to a problem in a conventional drawing apparatus.

[Explanation of symbols]

 Reference numeral 1 denotes a rectangle forming unit, and 2 denotes a joint figure forming unit.

Claims (3)

[Claims] 1. A drawing apparatus capable of drawing a line figure having a bent portion, wherein a rectangle forming means for forming at least two straight line segments having a width as a rectangular figure; A joint graphic forming means for forming the joint graphic forming means, wherein the joint graphic forming means moves a connecting point outside the rectangular graphic formed by the rectangular forming means by a small distance to the side of the rectangular graphic and the straight line segment. A drawing apparatus characterized by forming the connection figure including, as a vertex, a point at which a connection point is moved by a minute distance in a direction in which a line segment intersects widens. 2. A drawing apparatus capable of drawing a line figure having a bent portion, wherein: a rectangle forming means for forming at least two straight line segments having a width as a rectangular figure; A joint figure forming unit that forms the rectangular figure such that a side inside the bend of the straight line segment becomes longer by a small distance, and the joint figure forming unit forms the rectangular figure. A drawing apparatus, wherein the connected figure including a point at a vertex at which an outer joint point of the rectangular figure formed by a means is moved by a minute distance to the side of the rectangular figure is formed. 3. A drawing apparatus capable of drawing a line figure having a bent portion, wherein a rectangle forming means for forming at least two straight line segments having a width as a rectangular figure; And forming the joint figure forming means, wherein the rectangular forming means sets two end points of the straight line segment and each of the two points in the normal direction of the straight line to 1/1/2 of the line width.
A drawing apparatus for forming the rectangular figure constituted by a total of six points of four points moved by two.