JPH09223219A - Blocking management method for continuous line graphic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accelerate scrolling or to partially enlarge a continuous line graphic by dividing a graphic composed of continuous line into plural blocks, referring to information for the blocks including the continuous line qraphic displayed on a screen and displaying a part of the graphic on the screen. SOLUTION: The general drawing of the continuous line graphic is divided into uniform quadrangles so as to easily extract the blocks inside a plotting area. For instance, in the case of displaying the block including vertexes 3 and 4 in the continuous line graphic provided with the vertexes 1-5, the vertexes 6 and 7 are added at the boundary of the block of the continuous line and the graphic inside the block is plotted just by data managed by respective block single bodies. In this case, the vertexes of the graphic are not branched and the connection of vertex coordinates at the time of plotting the continuous line is sequenced as well. Also, in the case that the plural continuous lines are present inside the respective blocks, the number of the continuous lines inside the respective blocks and the data of the vertex coordinates for constituting the continuous line section are hierarchically managed in the respective blocks.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous line figure blocking management method, and more particularly to a continuous line figure blocking management method for continuous line data having a huge number of vertices such as map information.

[0002]

2. Description of the Related Art Conventionally, in a figure block management method for managing drawing data that cannot be displayed on a CRT screen as a whole by dividing it into blocks, scrolling the block drawing data is displayed. The method is used.

As an example of the above-described figure block management method, drawing data larger in size than the CRT screen surface of the overall view is divided into equal blocks, and an identification code is given to each block to display. At this time, the related identification number is referred to, the target to be displayed on the CRT is determined from the referenced block, and only the display target is output on the CRT, thereby scrolling large-scale drawing data at high speed. There is a technique (see Japanese Patent Laid-Open No. 4-346393).

[0004]

However, in the conventional device as described above, the drawing data is managed only by the identification code for each block in order to perform the scrolling at high speed. Since it is management, when a complicated continuous line figure or the like exists in a block or across two or more blocks, there is a problem that it is not possible to speed up scrolling or realize partial enlargement of the continuous line figure.

The present invention has been made in view of the problems of the above-mentioned conventional techniques, and in the case where a complicated continuous line figure or the like exists in a block or across two or more blocks. Another object of the present invention is to provide a block management method for continuous line figures, which can realize high-speed scrolling or partial enlargement of continuous line figures.

[0006]

In order to achieve the above object, the present invention is a method for managing a continuous line figure as a block, which displays a part of a figure consisting of continuous lines on a screen. The figure is divided into a plurality of blocks, vertices are set on the block boundaries of the continuous lines, the number of the continuous lines in each block, the coordinates of the vertices formed for each continuous line, and the blocks. By managing the information about the coordinates of the vertices set on the boundary and referring to the information about the block including the continuous line graphic to be displayed on the screen, a part of the graphic formed by the continuous line can be displayed on the screen. It is characterized by being displayed on.

The coordinates of the vertices are managed according to the order in which the continuous line is drawn.

(Operation) In the present invention, first, the whole drawing of the continuous line figure is divided into equal squares so that the blocks in the drawing area can be easily extracted.

FIG. 1 is a view showing a part of a block-shaped figure, (a) showing a continuous line and vertices, and (b).
FIG. 6 is a diagram showing a block of a hatched portion shown in (a).

As shown in FIG. 1, when displaying a block including vertices 3 and 4 in a continuous line figure having vertices 1 to 5, vertices 6 and 7 are added at the boundary of the block of the continuous line. , Drawing a graphic in a block only by the data managed by each block alone.

Here, it is assumed that the vertices of the figure are not branched, and the order of connecting the vertex coordinates when drawing a continuous line is also performed.

When a plurality of continuous lines exist in each block, the number of continuous lines existing in each block in each block and the data of the vertex coordinates forming the continuous line section are managed in a hierarchical manner. .

FIG. 2 is a diagram showing the whole figure divided into M × N blocks, in which block numbers 0 to M-.
Allocate as 1,0 to N-1. The shaded area is an enlarged display area.

Now, the coordinates of the vertex 101 at the lower left corner of the whole figure is (X ₀ , Y ₀ ), the coordinates of the vertex 102 at the upper right corner of the whole figure are (X ₁ , Y ₁ ), and the vertex at the lower left corner of the display area. The coordinates of 103 are (x ₀ , y ₀ ), and the coordinates of the vertex 104 at the upper right end of the display area are (x ₁ , y ₁ ).

[0015] The left end coordinates of the i-th block of Figure 2 X _i
Then, X _i = X ₀ + i (X _i −X ₀ ) / M, and to obtain the i-th mesh including the coordinate x ₀ of the vertex 103 at the lower left corner of the display area, X ₀ + i (X ₁ −X ₀ ) / M ≦ x ₀ <X ₀ + (i + 1) (X ₁
-X ₀ ) / M This may be rearranged to obtain an integer i such that i = [M (x ₀ −X ₀ ) / (X ₁ −X ₀ )] ([] is a Gaussian function).

Similarly, the mesh numbers included for y ₀ , x ₁ , and y ₁ are obtained, the block area 105 necessary for display is extracted, and the vertex data is extracted in that block according to the hierarchy of data management. Access and draw the continuous line by connecting the vertex coordinates according to the ordering.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3 is a diagram showing an embodiment of a method for managing blocking of continuous line figures according to the present invention.

As shown in FIG. 3, the whole continuous line data diagram having vertices 8 to 13 is divided into 2 × 2 blocks, and the vertices 14 to 1 at the block boundaries are used for data management.
Add 7. Note that (1,1) to (2,2) represent block identification numbers.

FIG. 4 is a diagram for explaining data management of the continuous line graphic shown in FIG.

The figure in the block (1,1) is composed of one continuous line, and the vertices which compose it are combined with those added in data management to form vertices 9,10,1.
Since it is 4,15, in the case of block (1,1),
Below the first continuous line, the vertices are ordered so that the continuous line of vertices 14 → 9 → 10 → 15 or vertices 15 → 10 → 9 → 14 is drawn, and data management is performed.

Next, the figure in the block (1, 2) is 2
Since it is composed of two continuous lines, the continuous line is divided into two, and the vertex is managed for each continuous line. Since the first continuous line is composed of vertices 8, 14, and 17,
Vertex 14 → 8 → 17 or vertex 1 in the order of connecting continuous lines
7 → 8 → 14, the second continuous line is the vertices 11, 15, 16
Since it is composed of, vertices 15 → 1 in the order of connecting continuous lines
Data management is performed by ordering 1 → 16 or vertices 16 → 11 → 15.

Since no continuous line figure exists in the block (2, 1), no data is stored.

Next, the figure in the block (2, 2) is 1
It is composed of a continuous line of books, and the vertices that compose it are vertices 12, 13, 16, and 17, so in the case of block (2, 2), below the first continuous line, Vertex 1
6 → 12 → 13 → 17 or vertex 17 → 13 → 12
→ The data is managed by performing the ordering of the vertices in the order of 16.

In this way, the whole view is divided into blocks, and the number of continuous lines existing in each block and the coordinates of the vertices forming the continuous line section are managed in a hierarchical manner.

It is assumed that the division work and the management of the vertex coordinate data are performed in advance by a program.

FIG. 5 is a diagram for explaining an example of displaying a part of the continuous line figure shown in FIG.

When displaying a graphic that extends over a plurality of blocks as shown in FIG. 5, first, the coordinate values at the four corners of each block are compared with the coordinate values at the four corners of the graphic to be displayed, and this is necessary for display. Extract blocks.

In the example shown in FIG. 5, the block (2,
1) and the block (2, 2) are required, the vertex coordinates of the block (2, 1) and the block (2, 2) are sequentially arranged for each continuous line according to the hierarchical management of data shown in FIG. Display figures by connecting them to each other.

As a result, the continuous line figure can be partially displayed without accessing any block outside the display area, the number of accesses to the vertex data can be minimized, and the partial drawing processing speed can be improved. Can be made.

[0031]

As described above, in the present invention,
A figure consisting of continuous lines is divided into multiple blocks, vertices are set on the block boundaries of the continuous lines, and the number of continuous lines in each block, the coordinates of the vertices configured for each continuous line, and the block boundaries are set. By managing the information about the coordinates of the set vertices and referring to the information about the block containing the continuous line graphic to be displayed on the screen, a part of the graphic consisting of the continuous line is displayed on the screen. Therefore, it is possible to display a part of the figure composed of the continuous line on the screen without accessing the data of the block outside the display area at all.

Thus, even when a complicated continuous line figure or the like exists in a block or across two or more blocks, it is possible to realize high speed scrolling or partial enlargement of the continuous line figure.

[Brief description of drawings]

FIG. 1 is a diagram showing a part of a block-shaped graphic,
(A) is a figure which shows a continuous line and a vertex, (b) is a figure which shows the block of the shaded part shown in (a).

FIG. 2 is a diagram showing an overall figure divided into M × N blocks.

FIG. 3 is a diagram showing an embodiment of a method of managing blocking of continuous line figures according to the present invention.

FIG. 4 is a diagram for explaining data management of the continuous line graphic shown in FIG.

FIG. 5 is a diagram for explaining an example of displaying a part of the continuous line figure shown in FIG.

[Explanation of symbols]

 1-17, 101-104 Vertex 105 Block area

Claims (2)

[Claims] 1. A method for managing a continuous line figure as a block, which displays a part of a figure consisting of continuous lines on a screen, wherein the figure consisting of continuous lines is divided into a plurality of blocks, and Setting vertices on block boundaries, and managing information about the number of continuous lines in each block, the coordinates of vertices formed for each continuous line, and the coordinates of vertices set on the block boundaries. However, by referring to the information about the block including the continuous line graphic to be displayed on the screen, a part of the graphic consisting of the continuous line is displayed on the screen, and the block management of the continuous line graphic is performed. Method. 2. The blocking management method for a continuous line figure according to claim 1, wherein the coordinates of the vertices are managed according to an order in which the continuous line is drawn. Method.