JP3475765B2 - Graphic display device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for displaying computer graphics (hereinafter, CG).

[0002]

2. Description of the Related Art CG is widely used in the fields of movies and video games. Furthermore, with the spread of the Internet in recent years, it has become common to distribute CG moving images via networks. C using the Internet
As an expression language for G moving images, "Virtual Real"
"ity Modeling Language" (hereinafter referred to as VRML) is in widespread use. For details, see VRML
Related site (http: //www.vrmlsit
e. com /).

In order to display a CG moving image, shape data for displaying a three-dimensional solid character and motion data for displaying the moving image are required.
In VRML, shape data and motion data are transferred from a server to a terminal using the Internet.

The terminal displays the received data as a CG moving image using a VRML browser. However, in such a method, the amount of data transfer increases and the data transfer time is long. Therefore, the prior art (Japanese Patent Application No. 09-1277)
No. 17, “Graphic Display Method and Device”) reduces the amount of data transfer by the following method.

The terminal has shape data and a plurality of motion data in advance. However, each of the motion data has a common home position at the beginning and end of the motion. The server sends scenario data that defines the order of combining motion data. The terminal receives the scenario data, switches the motion data in the order specified by the scenario, and displays it graphically. In this method, since only scenario data is transferred, the transfer time can be reduced as compared with VRML that transmits all data. Furthermore, since the beginning and the end of each motion data are provided with a common home position, if the motion data have the same home position, a natural graphic display of the joint of the motion data is realized.

[0006]

According to the above-mentioned conventional technique, the joint can be naturally displayed in the case of the motion data holding the common home position.
However, in the case of the motion data that do not hold the home position, the motions are discontinuous, and the joint between the motion data may be unnatural.

In view of the above-mentioned problems, the present invention provides a graphic display method and apparatus for displaying CG data distributed from a server through a communication line naturally even at motion data which do not hold a common home position in terminals. The purpose is to provide.

[0008]

In order to achieve the above object, the first invention of the present application is to provide a data transmission means for causing a server to transmit scenario data describing a combination order of motion data to a terminal through a communication line. Be prepared, the terminal
Data receiving means for receiving the scenario data transmitted by the data transmitting means, shape data required for displaying the three-dimensional character, motion data required for moving the three-dimensional character, and data received by the data receiving means. The motion switching display means for switching the motions in the order described in the scenario data to display the three-dimensional character and the motion data before and after are corrected so that the motions can be smoothly displayed when the switching display means switches the motions. The graphic display device is provided with a motion automatic correction means.

In a second aspect of the present invention, in addition to the first aspect of the present invention, a correction data transmitting means is added to the server for transmitting motion correction data for correcting a connecting portion between each motion data described in the scenario data through a communication line. In place of the automatic motion correction means of the terminal, a correction data receiving means for receiving the correction data transmitted by the correction data transmitting means and a motion display can be displayed smoothly when the switching display means switches the motion. The graphic display device further includes a motion correction unit that corrects the preceding and following motion data based on the motion correction data received by the correction data receiving unit.

A third invention of the present application is, in the first invention of the present application, motion correction data for correcting a connecting portion between each motion data described in the motion database and the scenario data transmitted from the motion database by the data transmitting means. And a correction scenario calculation means for calculating and transmitting through a communication line using the correction data transmission means.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) An embodiment of a graphic display device according to the first invention of the present application will be described below with reference to the drawings.

FIG. 1 is a block diagram of this embodiment. The server and terminal are connected by a communication line. The server is composed of the data transmission means 1.

The terminal comprises a data receiving means 11, a motion switching display means 12, a motion automatic correction means 13, a shape database 14, and a plurality of motion databases 15.

The data transmission means 1 transmits the scenario data to the terminal through the communication line. The scenario data defines the combination order of motion data.
That is, it is a list of motion IDs that specify motion data. However, it is assumed that the motion data corresponding to the motion ID has been previously supplied to the terminal through a recording medium such as a CD-ROM or a floppy disk or a communication line and stored in the motion database 15 of the terminal.

For example, the motion ID {Ma, Mb, M
When motion data corresponding to c, Md, Me} is stored in the motion database 15, [M
a, Mc, Ma, Me] (indicating that the display is switched and displayed sequentially from the head of the list) can be defined. However, the scenario [Ma, Mf, Ma, Me] cannot be specified because Mf is not stored in the motion database 14. Any combination of motion data stored in the motion database 15 can be defined as scenario data. The motion data will be described later.

The data receiving means 11 is the data transmitting means 1
The scenario data transmitted by is received through the communication line.

The shape database 14 stores shape data. Shape data consists of two or more three-dimensional (x,
It is composed of a set of polyhedrons called polygons composed of points of (y, z coordinates).

Motion data is stored in the motion database 15. The motion data defines the amount of change in shape data based on time series.

For example, the shape data of a triangular prism as shown in FIG. 2 has 6 vertices of a, b, c, d, e and f, and five subsets of the vertices {a, b, c} {d, e, f} {a,
b, d, e} {a, c, d, f} {b, c, e, f} can be defined by 5 polygon surfaces (this is referred to as object A). Motion data for rotating the object A by 180 degrees around the X axis and 360 degrees around the Y axis in 60 seconds is as shown in FIG. 3 (this motion is referred to as motion Ma).

It is not necessary to define the rotation angle of every frame to be displayed. The rotation angle is specified for a specific time (this is called a key frame), and the rest is calculated by an interpolation algorithm. Several types of general algorithms have been proposed as keyframe interpolation algorithms, but a one-dimensional linear interpolation algorithm will be described below.

Here, when the rotation angle of the X axis after 45 seconds is calculated using the one-dimensional linear interpolation algorithm, it is 100
(Degree) = [((45-40) / (50-40)) × (1
20-80) +80]. The motion database 15 is a set generally defined as a key frame set. When the change in motion is graphed, a motion graph as shown in FIG. 4 is obtained. Black circles and black triangles in FIG. 4 indicate key frames.

The motion switching display means 12 displays the CG moving image while sequentially switching the motion based on the scenario data received by the data receiving means. Each motion data is a set of key frames within a certain specific time (motion time). The motion Ma is motion data having seven key frames in 60 seconds. It is possible to restore the motion graph as shown in FIG. 4 by performing one-dimensional linear interpolation between key frames.

In the present embodiment, the keyframe interpolation is 1
Although dimensional linear interpolation is used, there are other known methods such as spline nonlinear interpolation. Since the same effect can be obtained by using any of the methods, the interpolation method is not particularly limited in the present invention.

For example, let us calculate the coordinates of the vertex a of the object A 45 seconds after the motion MA. First, the X-axis rotation angle,
The Y-axis rotation angle is calculated by linear interpolation. The rotation angle of the X axis is 100 degrees as calculated above, and the rotation angle of the Y axis is 300 degrees.
= [((45-40) / (50-40)) x (345-
255) +255]. First, 100 around the x-axis
Calculate the coordinates when rotated by a degree. x-axis rotation angle is xan
If g, then (x, y, z) becomes (x, y * cos (x
ang) + z * sin (xang), -y * sin (x
ang) + z * cos (xang)). Therefore, the value of a (3.0, 3.0, 1.0) is x = 3.0 y = 3.0 * (-0.174) + 1.0 * 0.984 =
0.462 z = -3.0 * 0.984 + 1.0 * (-0.174)
= -3.126 Next, the coordinates when the Y-axis is rotated by 300 degrees are calculated. If the z-axis rotation angle is yang, (x, y,
z) is (x * cos (yang) + z * sin (ya)
ng), y, -x * sin (yang) + z * cos
(Yang)).

X = 3.0 * 0.5 + (-3.126) *
(−0.866) = 4.207 y = 0.462 z = −3.0 * (− 0.866) + (− 3.126) *
0.5 = 1.035 Therefore, the vertex a after 45 seconds is (4.207, 0.4
62, 1.035). By applying the same calculation to the other five vertices, the coordinates of each vertex can be calculated.

A frame can be displayed by performing rendering processing after these coordinate conversion processing. The motion switching display means 12 displays a CG moving image by sequentially performing this series of processes based on the frame rate (defining how many frames are drawn per second) from the start to the end of each motion. When one motion finishes the CG moving image within the specified motion time, the display of the CG moving image of the next motion specified by the scenario data is started. In this way, the CG moving image is continuously displayed by switching the motions one after another.

The motion automatic correction means 13 corrects the motion data when the motion switching display means 12 switches the motion. When the motion data is displayed sequentially, the motion may become discontinuous at the joints.

For example, consider the case where the motion Mb is displayed after the motion Ma. A motion graph of the motion Mb is shown in FIG. Further, FIG. 6 shows a combination of Ma and Mb motion graphs.

As is clear from FIG. 6, the motion Ma 60
A discontinuity occurs in the second frame and the 0 second frame of the motion Mb.

Here, the discontinuity of motion is avoided by setting the average value of the respective values of the 60-th frame and the 0-th frame of Ma as the key frame when switching the motion. The key frame at the time of switching between Ma and Mb is calculated. Rotation angle of x axis 160 = (180 + 14
0) / 2, y-axis rotation angle 340 = (360 + 320) /
When 2 is set as the key frame at the time of switching, the motion graph is smoothly connected as shown in FIG.

When the motion is switched, the automatic motion correcting means 13 calculates a key frame from the preceding and following motion data and automatically corrects the motion data. There are a plurality of known correction methods. Since the same effect can be obtained by using any of the methods, the correction method is not particularly limited in the present invention.

(Second Embodiment) A second embodiment of the graphic display method of the present invention will be described below with reference to the drawings.

FIG. 8 is a block diagram of this embodiment. The server and terminal are connected by a communication line.

The server comprises a data transmission means 1 and a correction data transmission means 21.

The terminal comprises a data receiving means 11, a correction data receiving means 22, a motion switching display means 12, a motion correcting means 23, a shape database 14, and a plurality of motion databases 15. Here, since 1, 11, 12, 14, and 15 are the same as those in the first embodiment, description thereof will be omitted.

The correction data transmitting means 21 transmits data for correcting the motion data of the scenario data transmitted by the data transmitting means 1.

It is assumed that the motion correction data is previously calculated by the same method as the motion automatic correction means 13 described in the first embodiment. The motion compensation data defines the motion and the time of its frame. For example, the correction data for Ma and Mb are as shown in FIG. M
After a, Mb is switched and displayed. Ma 60-second keyframe (rotation angle 180 degrees on x-axis, rotation angle 360 on y-axis)
Degree) and Mb 0 second keyframe (rotation angle of x-axis 14
0 degrees, y-axis rotation angle 320 degrees), x-axis rotation angle 160
And the y-axis rotation angle is corrected to 340 degrees. Such correction data is necessary for the number of times each motion of the scenario data is switched. For example, when the scenario data specifies five motion data of {Ma, Mb, Mc, Md, Me}, (Ma, M
b), (Mb, Mc), (Mc, Md), (Md, M
The correction data for the joint between the motion data when switching the four sets of motion data in e) is required.
The correction data transmitting unit 22 transmits the motion correction data to the terminal.

The correction data receiving means 22 receives the correction data transmitted from the server. The motion correcting means 23 corrects the data based on the correction data received by the correction data receiving means 23 when the motion switching display means 12 switches the motion.

For example, when the correction data shown in FIG. 9 is received, the motion switching display means 12 changes from Ma to Mb.
When switching to, the key frames of 60 seconds and 0 seconds are respectively corrected to define the frame time of FIG. 7. For example, the correction data for Ma and Mb are as shown in FIG.

(Third Embodiment) The third embodiment of the graphic display method of the present invention will be described below with reference to the drawings. FIG. 10 is a block diagram of this embodiment.

The server and the terminal are connected by a communication line. The server includes a data transmitting unit 1, a motion database 15, a correction data transmitting unit 21, and a correction scenario calculating unit 31.

The terminal comprises a data receiving means 11, a correction data receiving means 22, a motion switching display means 12, a motion correcting means 23, a shape database 14, and a plurality of motion databases 15. Here, since 1, 11, 12, 14, 15, 21, 22, and 23 are the same as those in the first and second embodiments, description thereof will be omitted.

The correction scenario calculation means 31 calculates correction data based on the motion database 15 so that the motions of the scenario data transmitted by the scenario transmission means 1 can be displayed smoothly, and the correction data transmission means 2
2 to send to the terminal. The method of calculating the correction data is the same as that of the motion automatic correction means 13 described in the first embodiment, and thus the description thereof is omitted here.

[0044]

As described above, according to the graphic display method of the first invention, compared to the prior art, even if each motion data does not hold the home position, the motions are naturally connected and the CG moving image is connected. It is possible to display.

Further, according to the graphic display method of the second invention, since the correction data calculated in advance is transmitted from the server, it is possible to save the computer resources of the terminal.

Furthermore, according to the graphic display method of the third aspect of the present invention, the correction data is calculated in real time, so that the memory resource of the server can be saved.

From the above effects, the practical effects are great.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment.

FIG. 2 is a diagram of an object A according to the first embodiment.

FIG. 3 is a diagram showing motion data Ma according to the first embodiment.

FIG. 4 is a diagram showing a motion graph of motion data Ma according to the first embodiment.

FIG. 5 is a diagram showing a motion graph of motion data Mb according to the first embodiment.

FIG. 6 is a diagram showing a motion graph of motions Ma and Mb according to the first embodiment.

FIG. 7 is a diagram showing a corrected motion graph according to the first embodiment.

FIG. 8 is a block diagram of a second embodiment.

FIG. 9 is a diagram showing correction data according to the second embodiment.

FIG. 10 is a diagram showing correction data according to the third embodiment.

[Explanation of symbols]

1 Data transmission means 11 Data receiving means 12 Motion switching display means 13 Motion automatic correction means 14 Shape database 15 motion database 21 Correction data transmission means 22 Correction data receiving means 23 Motion compensation means 31 Correction scenario calculation means

─────────────────────────────────────────────────── --- Continuation of the front page (56) References JP-A-8-30807 (JP, A) JP-A-9-198522 (JP, A) JP-A-8-77387 (JP, A) JP-A-7- 210708 (JP, A) JP-A 64-1065 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G06T 15/70 G06T 13/00 CSDB (Japan Patent Office)

Claims (3)

(57) [Claims] 1. The server comprises data transmission means for transmitting scenario data describing a combination order of motion data to a terminal through a communication line, and data for the terminal to receive the scenario data transmitted by the data transmission means. The receiving means, the shape database necessary for displaying the three-dimensional character, the motion database necessary for moving the three-dimensional character, and the motion switching in the order described in the scenario data received by the data receiving means. A graphic display characterized by comprising motion switching display means for displaying a three-dimensional character, and motion automatic correction means for correcting motion data before and after so that the motion can be displayed smoothly when the switching display means switches the motion. apparatus. 2. The server is additionally provided with a correction data transmission means for transmitting, through a communication line, motion correction data for correcting a joint portion between motion data described in the scenario data transmitted by the data transmission means, Instead of the motion automatic correction means, the correction data receiving means for receiving the correction data transmitted by the correction data transmitting means and the correction data so that the motion can be smoothly displayed when the switching display means switches the motions. The graphic display device according to claim 1, further comprising a motion correction unit that corrects the preceding and following motion data based on the motion correction data received by the receiving unit. 3. The server calculates motion correction data for correcting a connecting portion between each motion data described in the scenario data transmitted from the motion database by the data transmitting unit, and the correction data transmitting unit is operated by the server. 2. The graphic display device according to claim 1, further comprising a correction scenario calculation means that is used to transmit through a communication line.