JPH07104959B2 - Growth model display - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to computer graphics, and in particular, a growth model display for modeling a process such as growth of trees or growth of crystals and displaying the animation on a display device. Regarding the device.

[Background of the Invention]

The process in which buds emerge, branches and leaves grow, and flowers bloom like trees, can be topologically expressed by the state transition rule model called the L system proposed by A. Lindenmayer. it can. (See “Physics of Life”, Modern Physics, Fundamentals 8 [2nd Edition], P417-444, Iwanami Shoten 1978.) This L-system has a model topological purpose, and is used in the growth process of trees. No research has been done that is tied to the realistic display of reality. In addition, as a conventionally known display method, there is a fractal theory in which a basic figure and a rate of change of the figure to the next shape are described to make the figure seem to branch and grow. , This method expresses the relationship between figures at a certain time, the description of the rate of change is a singular, position-only function, and does not track the actual growth process (in the case of trees, It just catches one scene of a tree at a certain time as the display order and gradually branches off from the trunk). Therefore, there was a problem that an animation that creates buds and flowers would not be possible.

[Object of the Invention]

In order to solve the above problems, the object of the present invention is to model a process such as tree growth or crystal growth using a state transition rule, and to realistically animate the growth (growth) process on a graphics display device. It is to provide a growth model display device for displaying.

[Outline of Invention]

The present invention, in order to achieve the above object, topological state transition rule information about the transition of the topological state for each growth step in the growth process of the growth model and the topological model of the topological model during the transition of the topological state. First storage means for inputting and storing shape / color change information relating to the shape and color change of each part, and an initial state of the topological state of the growth model and each part of the topological model. Second storage means for storing initial values of shape and color, a timing controller for generating a timing signal for sequentially advancing the growth step, and a second storage means for storing in the second storage means in accordance with the timing signal generated by the timing controller. From the initial state of the stored topological state to the first storage means Based on the stored topological state transition rules, the topological states in the sequential growth steps are calculated, and further stored in the first storing means from the initial values of the shape and color stored in the second storing means. And a processing means for calculating the shape and color of each part of the topological model in the sequential growth step based on changes in the shape and color of each part of the topological model, and the processing means calculates the shape and color in the sequential growth step. A growth model display device characterized by displaying a growth process on a graphic display device as an animation based on the topological state and the shape and color of each part of the topological model.

Further, the present invention is a state transition table for storing the topological state change information of the growth model in each step in which the whole period of growth or a certain period is divided into steps of constant time intervals, and the shape of each part of the topological model and A change rate table that stores a change rate of color, a current state table that stores a topological current state, a means that stores a current shape color table that stores a current shape and color, and a timing for sequentially advancing the growth step. Based on the timing controller that outputs a signal and the timing signal output from the timing controller, the state transition information at the current step and the current topological state are read from the state transition table and the current state table, respectively. Topology in the next generation step The determined and updated from the current topological state based Le state in the state transition information,
Further, the current shape and color information is read from the current shape color table, and the change rates thereof are read from the change rate table, and the shape and color in the next generation step are calculated based on the change rates of the current shape and color. The growth model display device is characterized by including a processing unit for determining / updating from the above, and displaying the growth process on the graphic display device as an animation based on the processing result of the processing unit.

Example of Invention

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is an explanatory diagram for modeling a process in which a tree sprouts, becomes a trunk, branches come out, and leaves come out and grow. First, in the display step 1, a state in which a bud has emerged from a blank state
It becomes A ₀ . This state transition is expressed as 1) S → A ₀ . Next, in display step 2, the sprout A ₀ becomes the trunk A ₁ , and at the same time, the branch emerges B _{0 on} the right and C ₀ on the left. This state transition is expressed as 2) A ₀ → A ₁ B ₀ C ₀ . In the display step 3, A ₁ , B ₀ and C ₀ grow to A ₂ , B ₁ and C ₁ , respectively. That is, the respective state transitions are 3) A ₁ → A ₂ 4) B ₀ → B ₁ 5) C ₀ → C ₁ , respectively. In each of the following display steps, the trunk A ₂ is set to A ₃ , A ₄ , ...
Since it only grows greatly, I will abbreviate the state transition to 3 ').

3 ') A ₁ → A ₂ → A ₃ → ... Now, at display step 4, leaves D ₀ and E ₀ come out from the branches B ₁ and C ₁ . This state transition is 6) B ₁ → B ₂ D ₀ E ₀ 7) C ₁ → C ₂ D ₀ E ₀ . The subsequent state transitions of the leaves D ₀ and E ₀ can be respectively expressed as 8) D ₀ → D ₁ → D ₂ → D ₃ → λ 9) E ₀ → E ₁ → E ₂ → E ₃ → λ. Here, λ is a special symbol indicating a dead state, and in this example, it is shown that the leaf D ₃ just after the display step 7 withers and disappears at the display step 8. The remaining state transitions are listed as follows: 10) B ₂ → B ₃ A ₀ 11) C ₂ → C ₃ A ₀ 12) B ₃ → B ₄ → B ₅ → …… 13) C ₃ → C ₄ → C ₅ → ...... is. In transitions 10) and 11), bud A ₀ emerges again, branching and expressing new leaves.

In this way, the growth process as shown in FIG. 1 can be topologically modeled by a total of 13 state transition rules. In order to actually give a realistic display of a tree using such a model, it is necessary to give necessary information on the shape and color corresponding to each state. At this time, in the case of simple growth as in the state transition rules 3 '), 12), and 13), it is sufficient to give the rate of change in shape and color. Furthermore, a part that controls the timing of the growth step is necessary. FIG. 2 shows an apparatus 100 configured to realize the above functions. First, the modeled state transition rule is registered in the transition table 160 by the input 110. This transition table 160 is read by the device 200 (15
1) The current state is read from the portion 170 holding the current growth state (step 150), the state of the next growth step is obtained, and the current state 170 is updated (step 152).
In addition, from the shape and color currently displayed, the transition table 16
The shape and color of the next growth step are obtained by referring to the transition rule of 0. Therefore, the part that retains the current shape and color 21
Read 0 (step 153). However, if the state transition does not change from branch to leaf, but is simple growth from branch to branch or from leaf to leaf, it suffices to give the rate of change of that growth, so keep the rate of change. The portion 190 that has been read is read (step 154). Based on this information, the device 200
Then, the shape and color of the next growth step are calculated, and the portion 210 holding the current shape is updated by this value (step 155). At the same time, this value is output to the display device (step 156). The default settings for current state portion 170 and current shape portion 210 are inputs 141 and 13 respectively.
Performed by 0. Input the rate of change to the section 190 12
Performed by 0. The number of growth steps (time) to be displayed in animation is set by the input 140, the timing control of the growth step is performed by the device 180, and the device 180 issues the growth step calculation start command one after another.

FIG. 3 shows a detailed data structure of the transition table 160. First, for each state, one table 310,
320 and 330 are secured, and the pointers of these tables are stored and managed in the transition state management table 300. The contents of the tables 310, 320, and 330 are, for example, the transition rule is A → BCD,
When the table 320 is reserved for the state A, the branch number 316 is entered in 316, and the pointer to the table 350 which stores the pointers in the tables for the three branch states B, C, and D is entered in 317. . Further, an attribute table 360 for storing the color of the figure in the state A and the rate of change to the next figure is prepared, the number of attributes is stored in 318, and the pointer to the attribute table 360 is stored in 319. . When the transition rule is simply applied n times, the number of application iterations n is stored in 314.

What is defined as a graphic having one state is called a cell graphic, and based on the data of the attribute table 360, the pointer to the program to be actually displayed is stored in 313. More complex shapes such as leaves
Since a partial state can be defined by being divided into partial figures, a pointer to a table for partial states is shown at 311. 3
12 is necessary when generating a figure from a partial state,
Stores a pointer to a table 340 for defining the initial shape.

FIG. 4 shows a detailed data structure of a table (170 and 210, respectively, which are actually connected as in this example) holding the current state and shape of the figure. Table 410 is called the route table,
The coordinates and the initial shape for starting the display of the model are given. Pointer to route table 410 is table 4
It is managed at 00. Since the structure of the route table 410 is the same as that used for holding the current state and shape of other cell shapes, the contents in the table described below are common to both. It is also common to the table 340 of FIG. A state table to show the state of the current shape
The pointers to 310 and 320 are stored in the table 411. A table 412 is used to store the reference position (world coordinate system) of each cell graphic, and a table 413 is used to store the coordinate-converted value of the table 412 in the display system. When the next step figure is obtained from the current figure, a plurality of child figures are newly created. Therefore, a new table is reserved for those figures and pointers to them are stored in 440. Then, the pointer to the table 440 is stored in the table 417. 416
Stores the number of those children (the number of branches). In addition, the child can use the ancestor pointer 41 to know who the parent is.
Store the pointer to the parent in 4. In addition, pointer 415 is used as a pointer connecting them to represent children born in the same generation. Parameter tables 450,460,480 are used to hold the current cell shape shape,
The pointers to those parameter tables are tables
The number of parameters is stored in the table 418. Because the same state transition rule is applied n times,
A table to count the number of applications so far
421 is used.

5 and 6 explain the contents of the program executed in the device 200. In the program 500, first, the pointer to the table for the root (root position) is taken out (step 510), it is judged whether or not the growth step zero is displayed from the beginning (step 520), and if so, the table Perform the initial setting of (step 521).
The processing contents are initialization of the set of the root coordinate value 412 and various pointers. Next, the processes from 531 to 580 are repeatedly executed until the current growth step reaches the display-specified growth step number (step 530). Timing here
The control corresponds to the function of the device 180. Step 530
In the processing in the loop, first, the contents of the generation pointer 415 are taken out from the table for the current cell figure and set to G (step 531). Then, the processes of steps 541 to 550 are repeatedly executed until G becomes NIL (pointer contents are empty), that is, until the youngest parent up to now.
Set the address of the current parent table to P (step
541), first, the growth of the parent figure is displayed and updated (step 542). Next, in order to check whether there is a branch of state transition, if the number of repetitions 314 is zero and the number of branches 316 is not zero, or if the count value 421 reaches the number of repetitions even if the number of repetitions is not zero. (Steps 543,544,54
6). Otherwise, jump to JA560. If the above conditions are met, the number of branches in the parent table is 416 and the number of branches is 3
Set 16 (step 547). Then, in order to branch and generate a child, a table 440 for a pointer to a child table is created and the pointer is registered 417.
(Step 547). For each child, the program 600 is repeatedly executed to create the tables 420, 430 for displaying cell graphics (step 550). Moving to FIG. 6, in the program 600, the table 420 for the i-th child is created,
The pointer is registered in the table 440 (step 61).
0). A pointer value P to the parent table is set in the ancestor pointer 414 of the table 420 (step 620). The address pointer of the table 420 is stored in the generation pointer 415 of the previous child table (step 630). The address of the state transition table 310 is stored in the state pointer of the table 420 (step 640). This system is 1
Since one state can be divided into a plurality of partial states, such a case is determined based on whether the partial state pointer 311 is NIL (step 650). If it is not NIL, in order to display the cell figure according to the partial state, first, the table 340 is read from the table 312, this is regarded as the route table, and the processing described so far is recursively performed (step 651). Otherwise, for NIL, Table 31
Link to the cell graphic display program from 3 and update / display the cell graphic (step 652). In this program, in order to update / display a specific cell figure, the following procedures are prepared. A procedure for obtaining a table address for a parent or also for that parent. Procedure to obtain coordinate address of specified table, table address for figure parameter, address for attribute table, etc. In addition, a procedure to refer to and change the contents in the specified table. Procedure to convert coordinates to display surface. For example, a graphic display procedure. Step 660 moves on to the generation of the next child. Returning to FIG. 5, when all the children are generated and displayed for one parent, the contents of the generation pointer 415 are taken out and the next parent is moved (step 5).
61). In step 540, the content of the generation pointer is NIL.
If so, the processing for all parents ends. Then, the generation pointer 415 of the table of the last one of the generated children is set to NIL to indicate the end of the new parent (step 570). Since the display calculation for one growth step has been completed, the current growth step is advanced by one and the loop of step 530 is repeated until the designated step is reached. When the designated step is reached, the animation display ends.

〔The invention's effect〕

According to the present invention, like a tree, a growth process in which a bud emerges, branches and leaves grow, and a flower eventually blooms, a topological state transition rule and each state figure are stored in a storage means such as a table. By describing and storing detailed data, it is possible to display a realistic animation on the graphic display device. Further, according to the present invention, since it is not necessary to define a detailed graphic for each growth step, modeling of the growth process and its input can be significantly simplified. Further, according to the present invention, by adopting a partial state transition rule or the like, the definition of a graphic can be made hierarchical, which is convenient. Further, according to the present invention, since the part that the user has to describe is limited to only the model and its data operation, there is an effect that it becomes a generalized system that does not need to consider other complicated control.

[Brief description of drawings]

FIG. 1 is a diagram showing modeling and a display example when animating the growth process, FIG. 2 is a block diagram of a device of the present invention system, FIG. 3 is a structural diagram of a state transition table, FIG. Four
FIG. 5 is a structural diagram of a table for storing the figure of the current growth step, and FIGS. 5 and 6 are diagrams showing a processing program of the method of the present invention. 160: table for managing state transition rules, 170: part for holding the current growth state, 180: part for timing and controlling the growth step, 190: part for holding the rate of change of the displayed figure, 200: control processor, 210
...... A part that holds the current growth shape.

Claims (1)

[Claims] 1. A state transition table for storing topological state transition information of a growth model in each step in which a whole period of growth or a certain period is divided into steps of a constant time interval, and a change in shape of each part of the topological model. A rate-of-change holding unit that stores a rate, a current-state holding unit that stores a topological current state, and a current-shape holding unit that stores a current shape; and a timing controller that outputs a timing signal for sequentially advancing the growth step. And based on the timing signal output from the timing controller, the state transition information in the current step and the current topological state from the current state holding unit are read from the state transition table, respectively, and read in the next generation step. Topological state based on the state transition information Serial determined from the current topological state -
Update, further read the current shape information from the current shape holding unit and the rate of change of the shape from the change rate holding unit, respectively, in the information and the information indicating the updated topological current state. And a processing unit for determining and updating the shape in the next generation step from the current shape based on the processing result of the processing unit.
A growth model display device characterized by displaying an animation on a display device.