JP4706723B2 - Method and apparatus for reducing and compiling figures - Google Patents

Description

  The present invention relates to a graphic reduction and compilation method and apparatus, and more specifically, to a graphic reduction and compilation method and apparatus for reducing and compiling figures, for example, plane figures of buildings in map data, without causing visual discomfort. .

  The map is expressed differently depending on the scale. The expression format is defined as a diagram. When a map with a certain scale is to be created, a map with a scale larger than the scale exists and when the contents of the map can be used, the map with the desired scale is created by compiling the map with the larger scale.

  For example, a map with a scale of 1/2500 can be reduced to create a map with a scale of 1/10000. Conventionally, a photograph of a map with a scale of 1/2500 is photographed and reduced to a scale of 1/10000, and then a person redraws each element such as a building on the basis of a diagram with a scale of 1/10000. In redrawing based on a human figure, it is easy to transform elements that are difficult to read by being reduced by photographic processing so that they are easy to read, and it is easy to omit elements that are too fine. However, advanced skills are required for such modifications and omissions.

Recently, maps are being digitized. Digital maps can be freely scaled by a computer. However, existing map processing software simply enlarges / reduces each element and representative building in the map at the same magnification when the map is enlarged / reduced.
Japanese Patent Laid-Open No. 10-074042 Japanese Patent Laid-Open No. 05-250420 Japanese Patent Laid-Open No. 08-329236

  When the map is reduced, the conventional map processing software simply reduces the building figure included in the map. In this case, not only the building is displayed too finely, but also the building shape is reduced while being preserved. This often leads to the display of unnecessary buildings or the display of unnecessarily fine building shapes, making the map after reduction difficult to see and noisy. In other words, the reduced map is often not represented by a diagram corresponding to the scale of the reduced map.

  An object of the present invention is to provide a graphic reduction / compilation method and apparatus that eliminates such inconvenience and automatically performs deformation and omission according to the scale after reduction.

  The figure reduction compilation method according to the present invention is a figure reduction compilation method for reducing and editing figure data composed of a plurality of vertices and inter-vertex connection lines connecting them in order, and the size of the input figure data is not less than a predetermined size. The removal determination step for removing if the size is less than the predetermined size, and the shape of the graphic data not removed by the removal determination step so that the line length of each inter-vertex connection line exceeds the predetermined reference length A deforming step for deforming, and a reducing step for reducing the shape of the graphic data deformed in the deforming step to a size smaller by a predetermined amount according to the output resolution, and the removal determining step circumscribes the input graphic data. A circumscribed rectangle setting step for setting a rectangle to be compared with a comparison in which the short side of the rectangle set in the circumscribed rectangle setting step is compared with a predetermined length Comprising a step, the rectangle of the short sides are set in the bounding rectangle setting step and removing a shorter than the predetermined length.

  A graphic reduction editing apparatus according to the present invention is a graphic reduction editing apparatus that reduces and edits graphic data composed of a plurality of vertices and inter-vertex connection lines that connect them in order, and the size of the input graphic data is a predetermined size or more. The removal determination means that removes if the size is less than the predetermined size, and the shape of the graphic data that is not removed by the removal determination means so that the line length of each inter-vertex connection line exceeds the predetermined reference length Deformation means for deforming, and reduction means for reducing the shape of the graphic data deformed by the deformation means to a size smaller by a predetermined amount according to the output resolution, the removal determination means to the input graphic data A circumscribed rectangle setting means for setting a circumscribed rectangle; and a comparing means for comparing a short side of the rectangle set by the circumscribed rectangle setting means with a predetermined length. The rectangle the shorter side set at a constant means and removing the shorter than the predetermined length.

  According to the present invention, the size of house data can be reduced to a size that matches a desired scale while maintaining the basic shape. In addition, since it is deformed into an easy-to-see shape on the target scale, an easy-to-see map can be obtained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a schematic block diagram of an embodiment of the present invention applied to digital map reduction. Here, for example, it is assumed that the house data on the map of 1/2500 is reduced to 1/10000, that is, the house shape is reduced at a reduction ratio of 1/4. The house data is composed of a plurality of vertices and line segment data that connects the vertices clockwise so as to show the outer shape, and generally has a polygonal structure.

  House data 10 on a map with a scale of 1/2500 is input to the removal determination device 12. The removal determination device 12 is a device that detects a house that can be ignored at a reduced scale and removes it in advance. The removal determination device 12 compares the circumscribed rectangle setting device 14 that sets a rectangle circumscribing the input house data, the short side of the rectangle set by the rectangle setting device 14 with the reference length La, and the short side is the reference length La. The comparator 16 outputs only the above house data to the subsequent stage.

FIG. 2 shows an example of the shape of the house data. The operation of the circumscribed rectangle setting device 14 will be described with reference to FIG. Each vertex of the house data, and _P 1 ~P _8. The circumscribed rectangle setting device 14 searches for the longest line segment (longest line segment) from the house data. In the example shown in FIG. 2, the line segment P ₈ -P ₁ is the longest line segment. The direction of the longest line segment _P 8 -P ₁ and Y-axis. In other words, if the house data is rotated around any vertex so that the longest line segment is on the Y axis, the subsequent processing becomes easy. The rotation angle may be stored and restored after the necessary processing.

Of the vertices P _{1 to} P ₈ of the house data, two points at the farthest end in the Y-axis direction are searched. In the example shown in FIG. 2, _{P 1} and _{P 6} is searched. The distance between the farthest two points P ₁ and P ₆ in the Y-axis direction is defined as one side of the target rectangle. Specifically, the distance between the intersection points when the perpendicular to the Y axis is dropped from the farthest two points P ₁ and P ₆ is one side of the target rectangle. The axis orthogonal to the Y axis is taken as the X axis. The two vertices whose intersection (perpendicular to the perpendicular line) with the X axis when a perpendicular is dropped from each vertex to the X axis are searched for. In the example shown in FIG. 2, it is P ₁ (or P ₈ ) and P ₅ . The distance between the legs of the perpendicular line drawn from the vertices P ₁ and P ₅ to the X axis is the length of another side of the target rectangle. The length of the shorter side of the obtained rectangle is compared with the reference length La. If the length is shorter than the reference length La, the house data is deleted.

  The deformation | transformation apparatus 18 simplifies the shape of the house data determined by the removal determination apparatus 12 as the magnitude | size more than fixed. Specifically, the deformation | transformation apparatus 18 simplifies a shape by repeating deformation | transformation of a house shape until the shortest side becomes more than the reference length Lb. Details of this will be described later.

  The reduction device 20 is a device that reduces the house data whose shape is simplified by the deformation device 18 to a size slightly smaller than a size simply reduced to a target scale (in this case, 1/10000). In general, the reduction device 20 is an output device (display device or printer) that displays the house shape of the house data output from the deformation device 18 and displays a map of a target scale (in this case, 1/10000). Reduce to a smaller size by half the line thickness. This is in order to avoid overlap with adjacent graphic lines. If you reduce the line width, it will shrink too much.

  The house data output from the reduction device 20 indicates a house shape having a size suitable for being represented on a target scale map. By providing the reduction device 20, it is possible to avoid the overlap of the line with the adjacent line figure on the target scale map, and to make the house shape easy to see.

  The control unit 22 includes a target scale (here, 1/10000) and a reduction ratio (here, 1/4 {= 1 / 10,000 / (1/1)) from the original scale (here, 1/2500). 2500)}) and the output resolution (for example, information indicating the output device). The control device 22 determines the reference lengths La and Lb from the target scale and reduction ratio, the reference length La to the comparison circuit 16, the reference length Lb to the deformation device 18, and the reduction rate and output resolution to the reduction device 20, respectively. Supply.

FIG. 3 shows an operation flowchart of the deformation device 18. First, the shortest side is searched (S1). A house shape model in which the side P ₁ P ₂ is the shortest side as shown in FIG. 4 will be described. When the shortest side P ₁ P ₂ is equal to or longer than the reference length Lb (S2), the difference θ between the direction angles of the rear side P ₆ P ₁ after the shortest side P ₁ P ₂ and the front side P ₂ P ₃ is calculated (S3). ), It is confirmed whether the angle θ is larger than the reference value and smaller than (360−reference value) (S4). The reference value is 170 °, for example. In steps S3 and S4, it is confirmed whether the front side and the rear side are substantially parallel and in opposite directions.

When the front side and the rear side are substantially parallel and in opposite directions (S4), a shape model having a protrusion with a width narrower than the reference length Lb as shown in FIGS. 5, 6, 7, and 8 is used. Can be assumed. 5 to 8, the side P ₁ P ₂ is the shortest side. In this specification, the side P _N P ₁ starting from the start point P ₁ of the shortest side P ₁ P ₂ is the rear side, and the side P ₂ P ₃ starting from the end point P _{2 of the} shortest side is the front side. 5 and 6 show a shape model when the front side length is greater than or equal to the rear side length, and FIGS. 7 and 8 show a shape model when the front side length is less than the rear side length. FIG. 7 shows a shape model obtained by horizontally inverting the shape model shown in FIG. 5, and FIG. 8 shows a shape model obtained by horizontally inverting the shape model shown in FIG.

The length of the front side P ₂ P ₃ is compared with the length of the rear side P _N P ₁ (S5). 5 and 6, the front side P ₂ P ₃ is longer than the rear side P _N P ₁ , and in the shape models shown in FIGS. 7 and 8, the front side P ₂ P ₃ is the rear side P _N P. Shorter than ₁ .

Before when the length of the side _P 2 _{P 3} is equal to or greater than the length of the rear side _P N _{P 1} (S5), i.e., with respect to the shape model shown in FIGS. 5 and 6, the end point _{P 3} of the front side _P 2 _{P 3} Is substantially on the line (including the extension line) of the rear side P _N-1 P _N of the rear side P _N P ₁ (S6).

When the end point P _{3 of the} front side P ₂ P ₃ is substantially on the line of the back rear side P _N-1 P _N (S6), the deformation is performed as shown in FIG. That is, first, from the shape shown in FIG. 5 (a), as shown in FIG. 5 (b), two end points _P 1 of the shortest side _P 1 _{P 2,} and _{P 2,} 2 vertices forming the bottom of the protruding portion One of P _N and P ₃ , for example, the vertex P ₃ is deleted, and the remaining vertex P _N is connected to the vertex P ₄ . However, if the length of the vertical line when a perpendicular line is dropped on the line segment _{P N-1 P 4} connecting the front and rear vertices _{P N-1, P 4} from its apex _{P N} is equal to or less than the reference length Lb, the apex Since there is no significance of leaving P _N , as shown in FIG. 5C, the vertex P _N is further deleted, and the vertexes P _N−1 and P ₄ are directly connected. In FIG. 5C, the protrusion including the shortest side is completely deleted.

When the end point P _{3 of the} front side P ₂ P ₃ is not substantially on the line of the back rear side P _N-1 P _N (S6), the end point P ₃ is deformed as shown in FIG. That is, the shape shown in FIG. 6 (a), as shown in FIG. 6 (b), delete the shortest side _P 1 end points _P 1 of _{P 2, P 2,} before the start of the rear side _P N _{P 1} A perpendicular is dropped to the side P ₂ P ₃ and the vertex P _N is moved to the foot P _Na . Thereby, the protrusion is deleted by the height of the rear side P _N P ₁ .

When the length of the front side P ₂ P ₃ is less than the length of the rear side P _N P ₁ (S5), that is, for the shape model shown in FIG. 7 and FIG. Performs processing that is reversed. That is, it is checked whether the starting point P _{N of} the rear side P _N P ₁ is substantially on the line (including the extension line) of the side P ₃ P ₄ further before the front side P ₂ P ₃ ( S9).

When the starting point P _{N of the} rear side P _N P ₁ is substantially on the line of the front front side P ₃ P ₄ (S9), the rear side P _N P ₁ is deformed as shown in FIG. That is, first, from the shape shown in FIG. 7A, as shown in FIG. 7B, the _two end points P ₁ and P ₂ of the shortest side P ₁ P ₂ and the two apexes that form the bottom of the protruding portion One of P _N and P ₃ , for example, the vertex P _N is deleted, and the remaining vertex P ₃ is connected to the vertex P _N−1 . However, if the length of the perpendicular line is less than the reference length Lb when a perpendicular line is drawn from the vertex _{P 3} to the line segment _{P N-1 P 4} connecting the vertex _{P N-1, P 4} of the front and rear, the vertex Since there is no significance of leaving P ₃ , as shown in FIG. 7C, the vertex P ₃ is also deleted, and the vertices P _N−1 and P ₄ are directly connected. In FIG. 7C, the protrusion including the shortest side is completely deleted.

If the starting point P _{N of the} rear side P _N P ₁ is not substantially on the line of the front front side P ₃ P ₄ (S9), it is deformed as shown in FIG. That is, the shape shown in FIG. 8 (a), as shown in FIG. 8 (b), delete the shortest side _P 1 end points _P 1 of _{P 2, P 2,} the end point _{P 3} of the front side _P 2 _{P 3} The vertical line is drawn down to the rear side P _N P ₁ and the vertex P ₃ is moved to the foot P _3a . As a result, the protrusion is deleted by the height of the rear side P ₂ P ₃ .

  By repeating the above, it is possible to delete a substantially rectangular protrusion whose top side is the shortest side.

  The process when the front side and the rear side of the shortest side are not substantially parallel or parallel but not in the reverse direction (S4) will be described. In this case, as shown in FIG. 9, when a side shorter than the reference length Lb exists alone, and when a side shorter than the reference length Lb is continuous as shown in FIGS. You could think so.

When a side P ₁ P ₂ shorter than the reference length Lb exists alone as shown in FIG. 9A (S12), as shown in FIG. 9B, the length of the previous side P ₂ P ₃ is The side P ₁ P ₂ is divided by the inverse ratio to the length of the subsequent side P _N P ₁ , and the division point is _defined as P _1a . That is, the dividing point P _{1a is set} so that the ratio of the length of the side P ₁ P _{1a to} the length of the side P _1a P ₂ is equal to the ratio of the length of the side P ₂ P _{3 and} the length of the side P _N P _1. Set. Then, an intersection of a line drawn through the dividing point P _1a and parallel to the rear side P _N P ₁ and a line (including an extension line) of the rear rear side P _N-1 P _N is defined as P _Na . Similarly, an intersection of a line passing through the dividing point P _1a and parallel to the front side P ₂ P ₃ and a line (including an extension line) of the front front side P ₃ P ₄ is defined as P _3a . The dividing point P _1a is used as an alternative point for the vertex P ₁ , the point P _Na is used as the alternative point for the vertex P _N , the point P _3a is used as the alternative point for the vertex P ₃ , and the point P _1a and the point P _Na are connected. connect _1a and the point _{P 3a,} it deletes the point _{P 2.}

Furthermore, when a perpendicular is drawn from the point P _1a to a line connecting the point P _Na and the point P _3a before and after the point P _1a, and the length of the perpendicular is equal to or shorter than the reference length Lb, as shown in FIG. The point P _1a is deleted, and a side connecting the point P _Na and the point P _3a is formed.

When the sides of the reference length Lb or less are continuous (S12), it is checked whether the number of the continuous sides is even or odd (S14). For even (S14), for example, if the line segment between the points _P 1 to P ₇ as shown in FIG. 10 (a) follows all reference length Lb, as shown in FIG. 10 (b), the even-numbered All the points P ₂ , P ₄ , P ₆ are deleted, and lines P ₁ P ₃ , P ₃ P ₅ , P ₅ P ₇ are newly set (S 15).

If the number of consecutive reference length Lb or less sides is odd (S14), for example, 11 if the line segment between the points _P 1 to P _6, as shown in (a) is less than all reference length Lb, 11 ( As shown in b), new points P _2a and P _4a are set in the middle between the even-numbered points P ₂ and P ₄ and the next (or previous) points P ₃ and P _5, and the reference The vertices P _{2 to} P ₅ located in the middle of the continuous side of the length Lb or less are deleted, and the start point P ₁ , end point P ₆ and the intermediate points P _2a and P _4a set here are connected in order (S16).

  Until the shortest side of the house data exceeds the reference length Lb (S2), the processes of steps S3 to S16 are repeated. When the shortest side of the house data exceeds the reference length Lb (S2), the above deformation process result is output and the deformation process is terminated (S17).

As shown in FIG. 5 to FIG. 8, when the top side of the small rectangular projection is the shortest side, the start point P ₁ and the end point P ₂ of the top side are deleted, and the vertex P _N , which forms the bottom of the projection, the P ₃ may be directly connected. Even if the length of the side P _N P ₃ is equal to or shorter than the reference length Lb, the deformation process # 5 (S13) provides a result similar to or similar to the above case.

  The functions of the removal determination device 12, the deformation device 18, the reduction device 20, and the control device 22 are realized by software on a computer, but of course, can also be realized by hardware. The reduction function of the reduction device 20 may be separated into a reduction to a target scale and a reduction corresponding to half of the resolution for improving the appearance. In that case, it is also clear that the former reduction function may be arranged in front of the removal determination device 12, for example.

  Although the embodiment applied to a house has been described, the present invention can also be applied to the case of reducing a general figure that is not limited to a house.

It is a schematic block diagram of one Example of this invention. It is an example of the shape of house data for demonstrating operation | movement of the circumscribed rectangle setting apparatus. 6 is an operation flowchart of the deformation device 18. It is a house shape model explaining the direction angle difference of a front side and a back side. It is a processing example of deformation | transformation process # 1 (step S7). It is a processing example of deformation | transformation process # 2 (step S8). It is a processing example of deformation | transformation process # 3 (step S10). It is a processing example of deformation | transformation process # 4 (step S11). It is a processing example of deformation | transformation process # 5 (step S13). It is a processing example of deformation | transformation process # 6 (step S15). It is a processing example of deformation | transformation process # 7 (step S16).

Explanation of symbols

10: Input house data 12: Removal determination device 14: circumscribed rectangle setting device 16: comparator 18: deformation device 20: reduction device 22: control device

Claims (14)

A graphic reduction / compilation method for reducing and compiling graphic data consisting of a plurality of vertices and inter-vertex connection lines connecting them in order,
A determination step of determining whether or not the size of the graphic data to be input is equal to or larger than a predetermined size, and removing if the size is smaller than the predetermined size;
A deformation step for deforming the shape of the graphic data not removed by the removal determination step so that the line length of each inter-vertex connection line exceeds a predetermined reference length;
A reduction step of reducing the shape of the graphic data deformed in the deformation step to a size smaller by a predetermined amount according to the output resolution,
The removal determination step includes a circumscribed rectangle setting step for setting a rectangle circumscribing the input graphic data, and a comparison step for comparing the short side of the rectangle set in the circumscribed rectangle setting step with a predetermined length, A graphic reduction / compilation method characterized by removing a rectangle whose short side is shorter than the predetermined length set in the circumscribed rectangle setting step. The transformation step is
A shortest edge search step for searching the shortest edge of each inter-vertex connection line;
A rectangle determination step for determining whether or not the shortest side is substantially one of the top side of the rectangular convex portion and the bottom side of the concave portion;
When the shortest side is substantially one of the top of the rectangular convex part and the bottom of the concave, delete the vertex that is the start point and end point of the shortest side and delete the shortest side that connects the vertices on both sides The figure reduction and compilation method according to claim 1, further comprising a step. The deformation step further includes
A continuous determination step for determining whether or not the connection line between vertices of the predetermined reference length or less continues;
When the connecting lines between vertices not more than the predetermined reference length are not continuous, the connecting lines between vertices not more than the predetermined reference length are divided by the line length ratio of the connecting lines between the vertices on both sides, and the dividing point is set as the end point. The parallel connection of the connecting lines between the vertices on both sides is performed, and the end points on the opposite side of the dividing points and the connecting lines between the vertices after the parallel movement are converted into the end points of the connecting lines between the vertices that are equal to or less than the predetermined reference length and the conversion points before the parallel movement. The figure reduction and compilation method according to claim 2, further comprising: a line deleting step as a substitute for the vertexes of the connecting lines between the vertices on both sides. The deformation step further includes
A vertex thinning step of thinning out every other vertex in the middle of the continuous inter-vertex connection line of the predetermined reference length or less;
A vertex substitution step of substituting every other vertex in the middle of the connecting line between successive vertices of the predetermined reference length or less with an intermediate point between adjacent vertices;
When the connecting lines between vertices below the predetermined reference length are continuous, the number of connecting lines between the vertices below the predetermined reference length is calculated, and according to the calculation result, the vertex thinning step and the vertex replacing step The figure reduction and compilation method according to claim 3, further comprising a selection step of selecting one.   The transformation step includes dropping a perpendicular from the noted vertex to a line connecting two vertices on both sides of the noted vertex, and deleting the noted vertex when the length of the perpendicular is equal to or less than the predetermined reference length. The figure reduction and compilation method according to claim 1, 2, or 3.   2. The graphic reduction and compilation method according to claim 1, wherein the reduction step reduces the shape of the graphic data deformed in the deformation step to a size smaller than a target scale size by a predetermined amount corresponding to the output resolution.   The figure reduction and compilation method according to claim 1, wherein the figure data is house data representing a house on a map. A graphic reduction and editing apparatus for reducing and editing graphic data consisting of a plurality of vertices and inter-vertex connection lines connecting them in order,
A removal determination means for determining whether or not the size of the figure data to be input is equal to or larger than a predetermined size,
Deformation means for deforming the shape of graphic data not removed by the removal determination means so that the line length of each inter-vertex connection line exceeds a predetermined reference length;
Reduction means for reducing the shape of the graphic data deformed by the deformation means to a size smaller by a predetermined amount according to the output resolution,
The removal determining means comprises a circumscribed rectangle setting means for setting a rectangle circumscribing the graphic data to be input, and a comparing means for comparing the short side of the rectangle set by the circumscribed rectangle setting means with a predetermined length, A graphic reduction / knitting device, characterized in that those whose short sides of the rectangle set by the circumscribed rectangle setting means are shorter than the predetermined length are removed. The deformation means is
A shortest edge search means for searching for the shortest edge of each inter-vertex connection line;
Rectangle determining means for determining whether the shortest side is substantially one of the top of the rectangular convex portion and the bottom of the concave portion;
When the shortest side is substantially one of the top of the rectangular convex part and the bottom of the concave, delete the vertex that is the start point and end point of the shortest side and delete the shortest side that connects the vertices on both sides The figure reduction and knitting device according to claim 8, further comprising: means. The deformation means further includes
Continuous determination means for determining whether or not the connection line between vertices of the predetermined reference length or less is continuous;
When the connecting lines between vertices not more than the predetermined reference length are not continuous, the connecting lines between vertices not more than the predetermined reference length are divided by the line length ratio of the connecting lines between the vertices on both sides, and the dividing point is set as the end point. The parallel connection of the connecting lines between the vertices on both sides is performed, and the end points on the opposite side of the dividing points and the connecting lines between the vertices after the parallel movement are converted into the end points of the connecting lines between the vertices that are equal to or less than the predetermined reference length 10. The figure reduction and knitting device according to claim 9, further comprising: a line deleting unit that substitutes for the vertexes of the connecting lines between the vertices on both sides. The deformation means further includes
Vertex thinning means for thinning out every other vertex in the middle of successive connecting lines between the vertices below the predetermined reference length;
Vertex replacement means for replacing every other vertex in the middle of the connecting lines between successive vertices of the predetermined reference length or less with an intermediate point between adjacent vertices;
When the connecting lines between vertices below the predetermined reference length are continuous, the number of connecting lines between vertices below the predetermined reference length is calculated, and according to the calculation result, the vertex thinning means and the vertex replacement means The graphic reduction / knitting device according to claim 10, further comprising selection means for selecting one.   The deformation means drops a perpendicular from the attention vertex to a line connecting two vertices on both sides of the attention vertex, and deletes the attention vertex when the length of the perpendicular is equal to or less than the predetermined reference length. The figure reduction and knitting device according to claim 8, 9 or 10.   9. The graphic reduction and knitting device according to claim 8, wherein the reduction means reduces the shape of the graphic data deformed by the deformation means to a size smaller than a target scale size by a predetermined amount corresponding to the output resolution.   The graphic reduction / compiling device according to claim 8, wherein the graphic data is house data representing a house on a map.

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