JP2908524B2 - Wood structure display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] The present invention relates to a tree structure display device for displaying a tree structure node on a display screen, and to display a well-balanced tree structure using display space efficiently. Calculating a width of an area to be allocated on the screen for each of the plurality of nodes, based on a ratio of weights allocated to the plurality of nodes which are child nodes of the constituent node according to the type of the node; A coordinate calculation unit that sets the center of the allocated area to the coordinates of each node; a node management table that stores the coordinate information of the nodes calculated by the coordinate calculation unit; A graphic library for holding a shape and a drawing unit for drawing a graphic representing a node on a display screen based on the coordinates of the node calculated by the coordinate calculation unit are provided.

The present invention relates to a tree structure display device that displays a tree structure node on a display screen, and more particularly to a tree structure display device that displays a tree structure used as a data management structure.

When designing algorithms or developing programs,
A tree structure is very often used as a data structure for managing data. In a program that handles a tree structure, data management is performed while dynamically changing the configuration of the tree structure by inserting or deleting data held in the tree structure based on input data.

Therefore, in order to test whether a program that handles a tree structure is working properly, it is necessary to confirm that each statement that operates the tree structure is working correctly by taking a trace or dump of the program. And it was difficult to debug. Therefore, in order to facilitate the debugging of a program that handles a tree structure, it is necessary to support the program development work of the programmer by visually expressing the tree structure that changes according to the operation of the program using graphics. is there.

[Related Art] A tree structure is a data structure that manages data hierarchically. FIG. 15 is a diagram showing a configuration example of a tree structure. The tree structure is composed of nodes called root node 1, intermediate node 2 and leaf node 3. Root node 1
Is a node located at the highest level in the tree structure, and the leaf node 3 is a node positioned at the end (lowest level) of the tree structure. All other nodes are intermediate nodes. Therefore, in order to display the tree structure, it is necessary to appropriately arrange each node constituting the tree structure.

Conventionally, when a dynamically changing tree structure is displayed, each node constituting the tree structure is arranged using a top-down method. In the top-down method, each node has a height H and a width W as attributes, divides the width W of the node by the total number of child nodes, and divides the width W of the parent node equally.
The height H and the width W 'of the child node are determined (the height H is constant). FIG. 16 is an explanatory diagram of the top-down method.

[Problem to be Solved by the Invention] When a tree structure is displayed using a top-down method, the width W of a parent node is equally divided according to the number of child nodes and assigned to child nodes. When a large number of child nodes are created below, the width of the child nodes is reduced, and as a result, there is a problem that the child nodes are overlapped with each other to make the display very difficult to see. FIG. 17 is a diagram showing an example of arrangement by equal division of regions. When a large number of child nodes are created under a certain parent node 4, the widths of the child nodes are reduced, and as a result, the child nodes overlap each other, and the display is very difficult to see.

In addition, to assign the same width to the child node as the leaf node, the same width as the child node as the other intermediate lead,
There is a problem that the area below the leaf node is wasted, the balance of the tree structure is deteriorated, and the display becomes difficult to see. FIG. 18 is a diagram showing an example of arrangement by equally dividing a region. Since the child nodes 5 and 6 that are the leaf nodes are assigned the same width as the other child nodes, the hatched areas in the figure are wasted.

As described above, in the conventional method, when a dynamically changing tree structure is displayed, since the nodes constituting the tree structure are not properly arranged, overlapping between the nodes and useless space on the display screen occur, and as a result, There has been a problem that the display of the tree structure is difficult to see.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a tree structure display device capable of efficiently displaying a tree structure using a display space efficiently.

[Means for Solving the Problems] FIG. 1 is a principle block diagram of the present invention. In the figure, reference numeral 10 denotes a coordinate calculation unit that calculates coordinates of a node on a display screen based on a weight assigned according to a type of a node constituting a tree structure based on an input command, and 11 denotes a coordinate calculation unit. A node management table that holds the calculated coordinate information of the node, 12 is a graphic library that holds the shape of the graphic representing the parent and child relationship between the node and the node, and 13 is based on the coordinates of the node calculated by the coordinate calculation unit 10, A drawing unit 14 draws a graphic representing a node on the display screen, and 14 is a display unit.

[Operation] The coordinate calculation unit 10 determines the region W of the node as shown in FIG.
_Bi is determined by W _Bi = (child node weight w _Bi ) × (parent node area W) × 1 / (parent node weight w _A ) (1) For example, when the weight of the parent node is 1 + n and the weights of the child nodes are 1 and n, respectively, the width W of the parent node is divided into 1 / (1 + n) and n / (1 + n). Here, the taking small as 1 the weight of the child nodes W _B1, the node is because that is the leaf node. Therefore, it is possible to provide a tree structure display device in which the width W of the parent is appropriately divided according to the weight of the child node, and the display space can be efficiently used to display a well-balanced tree structure.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

(1) Attributes of Nodes Each node constituting the tree structure holds a value described below as an attribute.

Region Each node has a height H and a width W as a region. The node is located at the center (W / 2, H) of the area.

Weight The relative value of the area assigned to each node according to the type of node is called weight. If the node type is a leaf node, it has no child nodes, so the weight is set to 1. If the node type is a root node or an intermediate node, it has a child node, so n (n ≧ 1) is given as the weight. . Thus, the root node and the intermediate node can have an area n times as large as the leaf node.

(2) Method of arranging nodes using weights In order to efficiently display a dynamically changing tree structure on a display screen, nodes are arranged using weights of each node. Under a certain node A, i child nodes Bi (i
When ≧ 1) is created, the area of the child node is calculated and arranged according to the following procedure.

The sum of weights of the all child nodes Bi and weight w _A with the A parent node.

Than the ratio of the weight w _Bi having a weight w _A and each child node of the parent node A, by dividing the width W of the region of the parent node, and the width W _Bi area of child nodes (height constant). The method of calculating the child node area is as shown in FIG.

The weight of each node is assigned according to the type of the node. As a result, the intermediate node has an area n times as large as the leaf node having no child node, and the space on the display screen can be efficiently used.

FIG. 3 is an explanatory diagram of a node arrangement method using weights.
The width of the display screen in the horizontal direction is 2000. The root node has an initial value of 2000, and the root node is located at the center of the width. Next, when an intermediate node is created as a child node of the root node, the weight of the parent node is the sum of the weights of the child nodes.
Equals 2n. Therefore, the area of the child node is determined by equation (1).

In the example shown, the node width is 1000 and the node width is 100
It becomes 0 and is arranged at the center of the area of each child node (FIG. 3A). Next, when two leaf nodes and one intermediate node are generated below the node, the weight of the node becomes n + 2.
, Are 1000 / (n + 2), 1000 / (n + 2), and 1000n / (n + 2), respectively, and are areas obtained by dividing the area of the parent node into 1: 1: n (FIG. 3 (b)).

One leaf node and one intermediate node from the node
Assuming that a number has been generated, FIG.
The arrangement is as shown in FIG.

FIG. 4 is a flowchart of the area division by the weighting method. The parent node is A, the child node is Bi, and the weight and width of the node are defined (S1). Next, it is checked whether the child node Bi is a leaf node (S2). If it is a leaf node, the weight is set to 1 (S3), and if it is an intermediate node, the weight is set to n (S4). next,
The width of the area of the node Bi is calculated based on the equation (1) (S
5) The coordinates of the node Bi on the display screen are calculated by the coordinate calculation unit 10.
(S6). When the display coordinates have been calculated, i =
i + 1 is updated (S7), and processing of the next node is started (S7).
2).

(3) Area collection method If the area allocated to the leaf node having no child node is collected after calculating the area of the child node based on the weighting arrangement method described in (2), more efficient display is performed. An arrangement can be made. FIG. 5 is a configuration block diagram of an arrangement for realizing the area collection method. First
The same components as those in the drawings are denoted by the same reference numerals. In the figure, reference numeral 15 denotes an area collection unit that collects an area assigned to a leaf node at the end of the tree structure from an area on the display screen assigned to nodes forming the tree structure.

For example, after calculating the area of the child node, the weight of the leaf node is temporarily set to 0, the total sum of the weights of the child nodes is calculated again, and the area is recalculated by using the expression (1). . As a result, the area of the parent node is divided only by the intermediate node of the child node, and as a result, the area allocated to the leaf node can be collected.

FIG. 6 is an explanatory diagram of the area collection method. In the display shown in FIG. 9A, the weight of a node that is a leaf node is set to 0. Since the weight of the intermediate node is n,
By the recalculation of the weight, the weight of the parent node becomes n, and when the recalculation is performed by the equation (1), the areas of the nodes and become 0, 0 and 1000, respectively. As a result, the area allocated to the leaf node is collected, and the node takes over the area of the parent node as it is.

Next, when a child node is similarly created under the node, the area of the node, is arranged in an area obtained by dividing the area 1000 of the node into 1: 1: n (FIG. 6 (b )reference). Here, the node is assumed to be a leaf node. In FIG. 3 (c), if two leaf nodes and one intermediate node are created below the intermediate node, the area will be as shown in FIG. 7 (a) unless the area is collected. When the collection is performed, the result is as shown in FIG. 11B. The area collection allows the area below the leaf node on the display screen to be effectively used, and the tree structure can be displayed more efficiently.

FIG. 8 is a flowchart of the area collection method. It is checked whether the node is a leaf node (S1), and if so, the weight is set to 0 (S2). If it is a leaf node, the area of the node Bi is recalculated based on the weight of the new node (S3). At this time, the equation (1) is used as it is. When the recalculation is completed, i = i + 1 and 1 are updated (S4), and the processing of the next node is performed.

(4) Rearrangement method When a plurality of child nodes are created one after another under a certain intermediate node, the tree structure changes dynamically, so that the child node cannot be displayed in the area allocated to the intermediate node. There is. FIG. 9 is a diagram showing an example in which child nodes overlap each other. Therefore, when the area between child leads falls below a certain threshold, the weight of the entire tree structure is recalculated,
By performing rearrangement by re-dividing the region, the overlap can be removed.

FIG. 10 is a configuration block diagram of an apparatus for realizing the rearrangement method. The same components as those in FIG. 5 are denoted by the same reference numerals. In the figure, reference numeral 16 denotes a detection unit for detecting whether or not nodes overlap each other on a display screen when displaying the nodes constituting the tree structure. Reference numeral 17 denotes a weight assigned to the node based on the detection result of the detection unit 16. Recalculate according to the type and number of
This is a rearrangement unit that rearranges nodes.

The recalculation of the weight is 1 for the leaf node and n for the intermediate node.
Then, the weight of the root node can be finally calculated by using the sum of the weights of the child nodes in order from the end (below) of the tree structure as the weight of the parent node. This will be described with reference to FIG. The figure shows that by setting the weight of the intermediate node to 3 and the weight of the leaf node to 1, the weight of the root node becomes 32 (the weight of the root node is located at the end of the tree structure at this time. The sum of the node weights).

By rearranging the area of each node again by the rearrangement unit 17 based on the recalculated weight, a tree structure can be displayed according to the number of nodes and the type of node. Also, in the recalculation of the area, the tree structure can be displayed more efficiently by using the methods shown in (2) and (3) together. When the tree structure shown in FIG. 9 is rearranged, a display as shown in FIG. 11 is obtained.

FIG. 12 is a flowchart of the rearrangement method. It is assumed that the coordinates of the node on the display screen are known. First, it is checked whether or not X-coordinate of sibling node−X-coordinate of node | ≧ min holds (S1). Where min
Is a threshold.

When the X coordinate of the sibling node−the X coordinate of the node | ≧ min holds, the nodes are adjacent to each other. On the other hand, when the above expression does not hold, the nodes overlap each other. In this case, check whether the node is a leaf node (S2),
If so, 1 is weighted (S3). If the node is an intermediate node, it is checked whether it is a child node (S4).

If there is no child node, the weight is set to 3 (S5). If there is a child node, the child node is called (S6), and the sum of the weights of the called child nodes is calculated to calculate the parent weight (S7). Thereafter, each node is arranged by area division (S8). Here, the components in FIG. 10 will be described in detail. First, the input command will be described. As a command to be input to the tree structure display device,
There are the following:

create (Root Node) Creates a root node and displays the root node on the display screen.

add (Parent Node, Children-List) Creates multiple child nodes under the specified parent node,
indicate.

recal (relocation execution instruction) The tree structure is relocated based on the attributes of each node registered in the node management table 11 at present.

The node management table 11 stores the weight of each node constituting the tree structure, the width of the area, the position on the display screen, and the parent-child relationship. FIG. 13 is a diagram showing a configuration example of the node management table 11. Node (Node), weight (weight), area width (width), position on the display screen (position), and parent-child relationship (Parent) are registered.

Next, upon receiving the input command, the coordinate calculation unit 10 calculates the weight of the parent node from the weight of the child node. By referring to the calculated weight and the value of the area width of the child node in the node management table 11, the width of the area of the child node is calculated, and the coordinates to be displayed on the screen of the child node are calculated. The calculated coordinates position (X, Y) and the width w of the area
The idth and the recalculated parent node weight are sent to the area collection unit 15. In addition, the calculated coordinate position (X,
Y) is stored in the node management table 11. The coordinate calculation unit 10 calculates the coordinates of the nodes in the tree structure on the display screen according to the following input commands.

create (Root Node) Creates a root node Root Node, calculates the coordinates of the root node on the display screen, and sends the calculated coordinate information to the area collection unit 15. Further, the root node Root Node and the calculated coordinate information are registered in the node management table 11.

add (Parent Node, Children-List) In order to create a plurality of child nodes under the specified parent node Parent Node, the coordinates of each node are calculated.

recal (relocation execution command) The coordinates are calculated based on the attributes of each node currently registered in the node management table 11, and the tree structure is rearranged.

In the area collection unit 15, the weight of the parent node is calculated from the coordinate calculation unit 10.
weight, the width of the area of the child node width and coordinate position
When (X, Y) is received, the coordinate position
Send (X, Y). At the same time, the area allocated to the leaf node is collected by the above-described area collection method, and the width of the recalculated child node area is set to the node management table 11
To be stored.

The detection unit 16 determines from the coordinates position (X, Y) of the child node sent from the area collection unit 15 whether or not the interval between the child nodes is equal to or less than the threshold. Send a relocation execution instruction. If the interval between the child nodes is equal to or greater than the threshold, the coordinate information of the child nodes is sent to the drawing unit 13.

When the relocation execution command is sent from the detection unit 16, the relocation unit 17 refers to the attribute of each node from the node management table 11, and reconfigures the weight of each node of the tree structure by the above-described relocation method. Perform calculations. The recalculated value is stored in the node management table 11 and fed back to the coordinate calculation unit 10. The coordinate calculation unit 10 refers to the updated weight of each node to obtain the width of the area,
The position (X, Y) is recalculated and stored in the node management table 11.

The graphic library 12 stores the definition of what kind of graphic is to be displayed on the display screen for each node constituting the tree structure and the parent-child relationship between the nodes. FIG. 14 is a diagram showing a configuration example of the graphic library 12. The node graphic represents a tree-structured node, and the connection line represents a parent-child relationship between the nodes. By the user's designation, the type of the node graphic representing the node and the type of the connection line representing the parent-child relationship between the nodes can be changed.

The drawing unit 13 sends a coordinate position (X,
When Y) is received, the node graphic and the connection line are displayed at the designated coordinates on the display screen based on the shape of the node defined in the graphic library 12 and the connection line information indicating the parent-child relationship between the nodes. When the coordinates of the already displayed node are changed by the rearrangement, the position of the node is moved from the position where the current node is displayed to the changed coordinate value.

[Effects of the Invention] As described in detail above, according to the present invention, a dynamically changing tree structure can be displayed in a well-balanced manner by efficiently using a display space.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the principle of the present invention, FIG. 2 is a diagram showing region division by weight of nodes, FIG. 3 is an explanatory diagram of an arrangement method of nodes using weights, and FIG. 4 is region division by weighting. FIG. 5 is a block diagram showing a configuration of an apparatus for realizing the area collecting method, FIG. 6 is an explanatory diagram of the area collecting method, FIG. 7 is a view showing an arrangement result by the area collecting method, and FIG. 9 is a diagram showing node overlap, FIG. 10 is a block diagram showing a configuration of an apparatus for realizing the relocation method, FIG. 11 is a diagram showing a display example based on the relocation method, and FIG. FIG. 13 is a diagram illustrating a configuration example of a node management table, FIG. 14 is a diagram illustrating a configuration example of a graphic library, FIG. 15 is a diagram illustrating a configuration example of a tree structure, and FIG. Illustration of top-down method, Fig. 17 is area Diagram illustrating an arrangement example by equally dividing, FIG. 18 is a diagram showing an arrangement example by equally divided regions. 1, 5 and 10, reference numeral 10 denotes a coordinate calculation unit, 11 denotes a node management table, 12 denotes a graphic library, 13 denotes a drawing unit, 14 denotes a display unit, 15 denotes an area collection unit, and 16 denotes a detection unit. Reference numeral 17 denotes a rearrangement unit.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-1-177123 (JP, A) JP-A 1-228064 (JP, A) JP-A 1-215155 (JP, A) JP-A-63-1988 211068 (JP, A) JP-A-61-290571 (JP, A) JP-A-62-14265 (JP, A) JP-A-58-223863 (JP, A) JP-A-1-134674 (JP, A) JP-A-61-271578 (JP, A) JP-A-3-147184 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G06F 17/50 G06F 9/06 JICST (JOIS)

Claims (3)

(57) [Claims] 1. A screen for each of a plurality of nodes constituting a tree structure, based on a ratio of weights assigned to the plurality of nodes as child nodes of the node according to the type of the node. A coordinate calculating unit that calculates the width of the area to be allocated above, and sets the center of the allocated area as the coordinates of each node; a node management table that holds the coordinate information of the node calculated by the coordinate calculating unit; A tree structure display device comprising: a graphic library that holds a shape of a graphic representing a parent-child relationship between the two; and a drawing unit that draws a graphic representing a node on a display screen based on the coordinates of the node calculated by the coordinate calculation unit. . 2. An area collecting unit for collecting an area allocated to a leaf node by allocating 0 as a weight to a leaf node and determining a width of an area allocated to an intermediate node among the plurality of nodes. The tree structure display device according to claim 1, wherein a space below the leaf node on the display screen is effectively used. 3. Displaying nodes constituting a tree structure,
A detection unit for detecting whether or not nodes overlap on a display screen; and a relocation for recalculating weights to be assigned to the nodes based on the detection result of the detection unit according to the type and number of the nodes, and relocating the nodes. 3. A unit is provided to prevent nodes constituting a tree structure from being overlapped on a display screen by rearrangement.
The described tree structure display device.