JP2001084391A - Image generation system and information storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image generation system and an information storage medium capable of realistically expressing shadows and highlights, etc. SOLUTION: The vertex of a car object 10 is projected in a projection direction, U and V coordinates of texture 20 for the highlight are calculated based on the X and Y coordinates of the vertex after projection and source picture texture and the texture for the highlight (or for the shadow) are multi-texture mapped on the car object. Then, an image from a virtual camera is generated by an optional position and direction. An offset value, a scaling value or the projection direction at the time of calculating the U and V coordinates from the X and Y coordinates is changed in real time. By executing a geometry processing to a shadow object, the texture for the shadow is generated. By superimposing and plotting an object for which the source picture texture is mapped and the object for which the texture for the highlight (for the shadow) is mapped, multi-texture mapping is realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an image generation system and an information storage medium.

[0002]

2. Description of the Related Art Conventionally, there has been known an image generation system for generating an image viewed from a given viewpoint (virtual camera) in an object space which is a virtual three-dimensional space. It is very popular for experiencing what is called virtual reality. Taking an image generation system that can enjoy a racing game as an example, a player operates a racing car (object) to run in an object space and competes with a racing car operated by another player or a computer. Enjoy a 3D game.

In such an image generation system, generating a more realistic image is an important technical problem in order to improve the virtual reality of the player. For this reason, it is desired that the shadow and highlight display of the object can be expressed more realistically.

[0004] As one technique for expressing shadows and highlights, for example, the following technique can be considered. That is, in this method, a shadow object for representing a shadow and a highlight object for representing a highlight are prepared in advance. Then, by placing these shadow objects and highlight objects on top of objects such as roads and cars, shadows and highlights are expressed.

However, this method has the following problems.

That is, there is no problem when the surface of the object (road, car) on which the shadow object or the highlight object is arranged is flat, but when the surface has a step, the shadow object or the highlight object is removed. , It looks like it's floating from the surface, or it looks like it's dive under the surface. That is, consistency between the shape of the shadow object or the highlight object and the shape of the step is not maintained, and an unnatural image is generated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide an image generation system and an information storage medium which enable realistic representation of shadows and highlights. Is to do.

[0008]

According to the present invention, there is provided an image generating system for generating an image, comprising: projecting a vertex of a first object in a given projection direction; Texture coordinate calculating means for calculating first and second texture coordinates of the projected texture based on the first and second coordinates of the vertex obtained by the projection, and an original picture texture of the first object are calculated. The projection texture specified by the first and second texture coordinates is mapped to a first object, and a drawing means for drawing the first object, and an image viewed from a virtual camera in an object space are generated. Means. Further, the information storage medium according to the present invention,
An information storage medium usable by a computer,
It is characterized by including a program for executing the above means. Further, the program according to the present invention is a program usable by a computer (including a program embodied in a carrier wave), and includes a processing routine for executing the above means.

According to the present invention, the vertex of the first object is projected, and the first and second texture coordinates of the vertex are calculated based on the first and second coordinates of the projected vertex. . Then, the texture of the original picture (texture of the model data) and the projection texture specified by the calculated first and second texture coordinates are mapped to the first object, and an image viewed from the virtual camera is generated. You. Therefore, according to the present invention, it is possible to generate an image when an object in which the texture of the original picture and the projection texture are multi-textured is viewed from an arbitrary position and an arbitrary direction. This makes it possible to express highlights, shadows, and the like realistically, thereby increasing the degree of realism of the image.

The image generation system, the information storage medium, and the program according to the present invention are arranged such that the texture coordinate calculating means calculates an offset when the first and second texture coordinates are calculated from the first and second coordinates. The value or the scaling value or the projection direction is changed in real time. By doing so, it is possible to change the position, size, and the like of a display object (highlight, shadow, and the like) represented by the projection texture in real time, thereby enabling various and rich image expressions.

Further, the image generation system, the information storage medium and the program according to the present invention are characterized in that the projection texture is a highlight texture for highlighting the first object. This makes it possible to highlight and display an arbitrary portion of the first object, and realize an excellent effect.

Further, the image generation system, the information storage medium and the program according to the present invention are characterized in that the projection texture is a shadow texture for casting a shadow of a second object on a first object. With this configuration, it is possible to perform a shadow expression in which the shadow of the second object is dropped on an arbitrary position of the first object, and it is possible to increase the degree of realism of the image.

The image generation system, the information storage medium, and the program according to the present invention are characterized in that the shadow texture is generated by performing a geometry process on the second object. In this way, when the shape of the second object changes or the projection direction changes, the shape and position of the shadow cast on the first object also changes, enabling a variety of rich image expressions. become.

Further, the image generation system, the information storage medium and the program according to the present invention are characterized in that the texture coordinate calculating means rotates the vertices of the first object by a given rotation matrix to obtain the first and second vertices. The first and second texture coordinates of the projected texture are calculated based on the second coordinates. If you do this,
With a simple process, it is possible to project the vertices of the first object and obtain the first and second coordinates of the vertices after the projection.

Further, in the image generation system, the information storage medium and the program according to the present invention, the drawing means draws a first object based on object data of the first object and an original picture texture. The coordinate calculating means replaces the first and second texture coordinates of the original picture texture included in the object data of the first object with the first and second texture coordinates of the calculated projected texture. , The first object is drawn based on the object data in which the first and second texture coordinates have been replaced and the projection texture. If you do this,
Even an image generation system that does not have a multi-texture mapping function (in a narrow sense) that maps a plurality of textures onto one object in an overlapping manner can realize multi-texture mapping.

[0016]

Preferred embodiments of the present invention will be described below with reference to the drawings. In the following, the case where the present invention is applied to a racing game will be described as an example, but the present invention is not limited to this and can be applied to various games.

1. Configuration FIG. 1 shows an example of a block diagram of the present embodiment. In the figure, the present embodiment only needs to include at least the processing unit 100 (or may include the processing unit 100 and the storage unit 170, or the processing unit 100 and the storage unit 170 and the information storage medium 180), and other blocks. (For example, the operation unit 16
0, the display unit 190, the sound output unit 192, the portable information storage device 194, and the communication unit 196) can be optional components.

The processing unit 100 performs various processes such as control of the entire system, instruction of instructions to each block in the system, game processing, image processing, and sound processing. Processor (CPU, DSP)
Or an ASIC (gate array or the like) or a given program (game program).

The operation section 160 is used by a player to input operation data, and its function can be realized by hardware such as a lever, a button, and a housing.

The storage unit 170 stores the processing unit 100 and the communication unit 1
A work area such as 96
It can be realized by hardware such as.

An information storage medium (storage medium that can be used by a computer) 180 stores information such as programs and data.
D, DVD), magneto-optical disk (MO), magnetic disk, hard disk, magnetic tape, or memory (RO
M) and the like. Processing unit 10
0 performs various processes of the present invention (the present embodiment) based on the information stored in the information storage medium 180. That is, the information storage medium 180 stores information (a program or a program and data) for executing the means (particularly, the blocks included in the processing unit 100) of the present invention (the present embodiment).

A part or all of the information stored in the information storage medium 180 is transferred to the storage unit 170 when the power to the system is turned on. Information storage medium 1
The information stored in 80 is a program code for performing the processing of the present invention, image data, sound data, shape data of a display object, table data, list data, information for instructing the processing of the present invention, and instructions for the processing. The information includes at least one of information for performing processing according to.

The display unit 190 outputs an image generated according to the present embodiment.
LCD or HMD (Head Mount Display)
It can be realized by hardware such as.

The sound output section 192 outputs the sound generated according to the present embodiment, and its function can be realized by hardware such as a speaker.

The portable information storage device 194 stores personal data and save data of the player, and the portable information storage device 194 may be a memory card, a portable game device, or the like. .

The communication unit 196 performs various controls for communicating with an external device (for example, a host device or another image generation system), and has a function of various processors or a communication ASIC. Hardware and programs.

A program or data for executing the means of the present invention (this embodiment) is distributed from the information storage medium of the host device (server) to the information storage medium 180 via the network and the communication unit 196. It may be. Use of the information storage medium of such a host device (server) is also included in the scope of the present invention.

The processing section 100 includes a game processing section 110, an image generation section 130, and a sound generation section 150.

Here, the game processing section 110 performs processing for accepting coins (price), setting processing for various modes, processing for proceeding with a game, setting processing for a selection screen, the position and rotation angle of the object (X, Y or Z axis rotation). Processing to determine the rotation angle), processing to move the object (motion processing), processing to determine the viewpoint position (the position of the virtual camera) and the line of sight (the rotation angle of the virtual camera), and placing objects such as map objects in the object space Various game processes, such as a process for performing a game, a hit check process, a process for calculating a game result (result and performance), a process for a plurality of players to play in a common game space, and a game over process, from the operation unit 160. Operation data, personal data from the portable information storage device 194, stored data, and game programs. It carried out based on, for example.

The image generation unit 130 includes a game processing unit 110
Various image processing is performed in accordance with an instruction or the like from, for example, an image viewed from a virtual camera (viewpoint) in the object space is generated and output to the display unit 190. Further, the sound generation unit 150 performs various types of sound processing in accordance with an instruction from the game processing unit 110, and performs BGM, sound effects,
A sound such as a voice is generated and output to the sound output unit 192.

The game processing section 110 and the image generation section 1
30, all of the functions of the sound generation unit 150 may be realized by hardware, or all of them may be realized by a program. Alternatively, it may be realized by both hardware and a program.

The image generation unit 130 includes the geometry processing unit 1
32 (a three-dimensional coordinate calculation unit) and a drawing unit 140 (rendering unit).

Here, the geometry processing unit 132 performs various types of geometry processing (three-dimensional coordinate calculation) such as coordinate conversion, clipping processing, perspective conversion, and light source calculation.
In the present embodiment, the object data (vertex coordinates of the object,
The vertex texture coordinates or the luminance data are stored in the main memory 172 of the storage unit 170.

The drawing unit 140 stores the object data after the geometry processing (after the perspective transformation) and the texture storage unit 1
The object is drawn in the frame buffer 174 based on the texture stored in 76. This allows
In the object space where the object moves, an image that can be seen from the virtual camera (viewpoint) is generated.

The geometry processing unit 132 includes a texture coordinate calculation unit 134.

Here, the texture coordinate calculation unit 134 projects the vertices of the object in a given projection direction (parallel projection,
Perspective projection etc.). Then, based on the first and second coordinates (for example, X and Y coordinates) of the vertex obtained by the projection,
First and second texture coordinates (for example, U and V coordinates) of the projected texture are calculated.

The drawing unit 140 includes a texture mapping unit 142.

Here, the texture mapping unit 142
Maps the original picture texture (texture included in the model data in advance) of the object and the projection texture specified by the first and second texture coordinates calculated by the texture coordinate calculation unit 134 to the object. Thus, an object in which the original picture texture and the projection texture are multi-textured is drawn. Then, in this case, from any virtual camera's viewpoint, an image is generated as if the projected texture were projected on the object from the projection direction, and the optimal image expression for displaying highlights and shadows Can be realized.

The image generation system according to the present embodiment
A system dedicated to the single player mode in which only one player can play, or a system including not only such a single player mode but also a multiplayer mode in which a plurality of players can play, may be used.

When a plurality of players play,
The game image and the game sound to be provided to the plurality of players may be generated using one terminal, or may be generated using a plurality of terminals connected by a network (transmission line, communication line) or the like. Is also good.

2. Features of this embodiment (1) Highlight (spotlight) display In this embodiment, first, as shown at B1 in FIG. 2, each vertex of the car object 10 is projected in a given projection direction (parallel projection, perspective projection). Projection etc.). That is, for example, in the case of parallel projection, each vertex of the car object 10 is rotated by a rotation matrix in the projection direction.

Next, as shown in B2, based on the X and Y coordinates of the vertices after projection, the following formula is used to calculate
The U and V coordinates (texture coordinates in a broad sense) of the vertex are calculated. The U and V coordinates correspond to the highlight texture 2
The read address is 0 (projection texture in a broad sense). In the highlight texture 20, the middle area 22 is transparent, and the other areas 24 are black and translucent.

According to the present embodiment, as shown in B3, the original picture texture (the texture of the car model data) and the highlight
0 to generate an image viewed from the virtual camera 12. As a result, an image in which the original picture texture and the highlight texture 20 are multi-textured on the car object 10 can be displayed.

Note that the multi-texture mapping in this case may be realized by overlaying a plurality of textures on one object, or by overlaying a plurality of objects onto which different textures are mapped. It may be realized.

FIGS. 3A, 3B, 4A and 4B
FIG. 1 shows an example of an image generated by the present embodiment.

According to the present embodiment, the highlight 30 can be displayed on the car object 10 as shown in FIG. In this case, the middle region 22 of the highlight texture 20 in FIG. And
In this case, since the area 22 is transparent, the image of the car object 10 can be clearly seen in that area. On the other hand, the area 2 of the highlight texture 20
4 is translucent black, and in that area, the image of the car object 10 becomes blurred in the dark.

The U and V coordinates are both 0.0 ≦ U ≦
The limit value is set so as to be in the range of 1.0, 0.0 ≦ V ≦ 1.0. For example, if the U and V coordinates calculated from the X and Y coordinates are larger than 1.0, their values are forcibly set to 1.0, and if they become smaller than 0.0, The value is forced to 0.0.
In this way, a black translucent highlight texture is mapped in all places except the area 22. Thus, as shown in FIG. 3A, an image in which only the highlight 30 is displayed brightly can be displayed.

According to the present embodiment, highlight 3
The shape of 0 follows the shape of the surface of the car object 10 at the location where the highlight is displayed. That is, if there is a step on the surface of the car object 10, the highlight 30 is deformed and displayed so as to follow the shape of the step. As described above, according to the present embodiment, it is possible to realize the display of the realistic highlight 30 in which the consistency with the surface shape of the car object 10 is maintained.

Further, according to the present embodiment, even if the position or the rotation angle of the virtual camera 12 changes as shown at B4 in FIG. 2, the position where the highlight 30 is displayed does not change. That is, even when the virtual camera 12 moves and looks at the car object 10 from the right side as shown at B5 in FIG. 2, even when the virtual camera 12 moves and looks at the car object 10 from the right front as at B6, The highlight 30 is always displayed at the same place (for example, the place shown in FIG. 3A). Therefore, the appearance of the highlight 30 displayed on the car object 10 can be seen from various angles, and various and rich image expressions can be realized.

In the present embodiment, the offset values for calculating the U and V coordinates from the X and Y coordinates of the projected vertices (the parameters in the calculation formula for obtaining the U and V coordinates from the X and Y coordinates) are used. 3), the highlight 30 can be moved to an arbitrary place as shown in FIG. Thus, FIGS. 3A and 3B and FIGS.
As shown in (A) and (B), the highlight 10 is moved to various places on the car object 10 and only the portion of the image of the car object 10 illuminated by the highlight 10 is shown to the player. Such an effect can be achieved.

In addition, even when the highlight 30 is moved, the shape of the highlight 30 always follows the shape of the surface of the car object 10. Therefore, it is possible to give the player a virtual reality feeling as if the real light is shining.

It should be noted that U,
Scaling value for calculating the V coordinate (1 of the parameters in the formula for calculating the U and V coordinates from the X and Y coordinates
), The highlight 30 can be deformed to an arbitrary size. Thus, for example, projection by a point light source can be expressed in a pseudo manner.

(2) Shadow Display According to the present embodiment, a realistic expression can be made even for the shadow of an object.

In this case, first, a shadow object 40 as shown in FIG. 5A is prepared. Here, a shadow object 40 which is a black sphere is prepared in order to create a shadow of the sphere object.

Next, the shadow object 40 is subjected to geometry processing (coordinate transformation, perspective transformation, etc.) to obtain a shadow object as shown in FIG.
A shadow texture 42 as shown in FIG. That is, an image obtained by perspective-transforming the shadow object 40 to the screen is used as the shadow texture 42. In FIG. 5B, the shadow area 44 is translucent black, and the other areas 46 are transparent.

If the shadow texture 42 is generated from the shadow object 40 in this manner, for example, when the shape of the shadow object 40 changes, the shape of the shadow area 44 of the shadow texture 42 also changes. . Therefore, the shape of the actual shadow cast on the object (room object) also changes. That is, the shadow object 40
By changing the shape of the image, the shape of the actual shadow can also be changed, and more diverse and rich image expression can be realized.

Further, if the shadow texture 42 is generated from the shadow object 30, it is possible to generate a shadow according to the projection direction (direction in which the shadow is cast). That is, by changing the projection direction, the shape of the shadow changes, and a more realistic image expression can be realized. (However, when the shadow object 30 is a spherical object, even if the projection direction is changed, The shape of the shadow does not change).

Next, a room object 50 (object for dropping shadow) as shown in FIG. 5C is prepared, and each vertex of the room object 50 is set in a given projection direction as described in B1 of FIG. To project.

Next, as described in B2 of FIG. 2, the U and V coordinates of the vertex are calculated based on the X and Y coordinates of the vertex after projection. The U and V coordinates correspond to the shadow texture 42.
This is a read address of (projection texture in a broad sense).

Then, as described in B3 of FIG. 2, the original picture texture (texture of the room model data) and the shadow texture 42 are mapped to the room object 50 to generate an image viewed from the virtual camera. As a result, an image in which the original picture texture and the shadow texture 42 are multi-textured on the room object 50 can be displayed.

For example, in FIG. 6A, the light 54 from the light source (parallel light source) at the upper right causes the shadow 54 of the sphere object 52 to fall on the position of C1 at the left corner of the room object 50. As described above, according to the present embodiment, the shape of the shadow 54 conforms to the shape of the location of C1 of the room object 50, so that it is possible to express an unprecedented realistic shadow. Further, even if the virtual camera 12 moves, the shadow 5
No. 4 is always dropped to the location of C1, so that a consistent image can be provided.

In FIG. 6 (B), the shadow 54 of the sphere object 52 has fallen to the location C2 on the left of the room object 50 due to the light from the right light source. FIG.
In the figure, the shadow 54 of the sphere object 52 has fallen to the position of C3 on the far side below the room object 50 due to the light from the light source on the near side on the upper side.

As described above, according to the present embodiment, by changing the projection direction (the direction in which the shadow is cast; the direction of the light source) in real time, the place where the shadow 54 falls also moves in real time. Therefore, it is possible to give the player a virtual reality feeling that the shadow 54 of the ball object 52 is falling due to real light.

Furthermore, according to the present embodiment, when the projection direction is changed, the shadow 54 moves so that the shape of the room object 50 changes while maintaining the consistency with the shape of each place. As a result, an unprecedented real image can be provided.

The image that can be expressed by the present embodiment is not limited to a highlight or shadow image.

For example, as shown in FIG. 8A, an image of a glass 60 containing liquids 62 of various colors can be generated by the present embodiment. In this case, for example, even when the cup 60 is inclined as shown in FIG. 8B, it is possible to express that the surface 64 of the liquid 60 is not inclined.

Also, as shown in FIG. 8B, the water level of the surface 64 of the liquid 50 can be changed in real time by changing the offset value when calculating the U and V coordinates from the X and Y coordinates of the projected vertex. Can also be changed.

As shown in FIG. 8C, by performing animation of the texture to be projected, it is also possible to express an image such as making the surface 64 of the liquid 50 rippling.

According to the present embodiment, FIG.
As shown in (B), a cover 74 is attached to the car object 70.
, And the cover 74 can be gradually removed.

Further, according to the present embodiment, it is possible to express objects such as inserting parallel lines. This allows
For example, an image of a mountain object or the like on which contour lines are drawn can be generated.

(3) Multi-Texture Mapping In the present embodiment, multi-texture mapping of the original picture texture and the projection texture is realized by, for example, a method described below.

That is, first, as shown in (A1) of FIG.
Geometry processing is performed based on object data (vertex coordinates, vertex texture coordinates, brightness, and the like of the object) on the main memory, and the object data after the geometry processing is stored in the main memory and stored without being erased.
That is, geometry processing such as coordinate transformation, clipping processing, and perspective transformation is performed based on the object data, and the object data after perspective transformation is stored in the main memory.

Next, as shown in (A2) of FIG.
The original picture texture is transferred to the M texture storage unit (texture storage area) (may be transferred before the geometry processing).

Next, as shown in (A3) of FIG. 10, the VRA is performed based on the object data after the geometry processing and the original picture texture stored in the texture storage unit.
Draw the object in the M frame buffer. As a result, an object on which the original picture texture is mapped is drawn on the frame buffer.

Next, as shown in (A4) of FIG. 10, the U and V coordinates (texture coordinates) of the original picture texture included in the object data after the geometry processing are calculated using the U, V calculated by the method of FIG. Replace with the V coordinate (overwrite the calculated U and V coordinates).

Next, as shown in (A5) of FIG. 10, the projection texture (highlight texture, shadow texture) is transferred to the texture storage unit, and the texture mapped to the object is changed from the original picture texture to the projection texture. Change to

Next, as shown in (A6) of FIG. 10, based on the object data after the geometry processing stored in the main memory and the projection texture stored in the texture storage unit, the frame buffer is stored. Draws objects by overlaying them by alpha blending. This allows
The object to which the projection texture is mapped is drawn on the object to which the original picture texture is mapped.

By performing the above processing within one frame,
Even in an image generation system that does not support the function of multi-texture mapping (narrow sense), multi-texture mapping (broad sense) can be realized.

Further, in the present embodiment, the object to which the projection texture is mapped is drawn based on the object data after the geometry processing already stored in the main memory. Therefore, it is not necessary to perform the geometry processing on the object again, and only once, so that multi-texture mapping can be realized without increasing the processing load so much.

In particular, geometry processing (three-dimensional coordinate calculation)
Is a very heavy process because it needs to be performed on all vertices of the object. Therefore, by performing this geometry processing once instead of twice,
Processing load can be greatly reduced.

3. Next, a detailed example of the process according to the present embodiment will be described with reference to the flowcharts in FIGS. 11, 12, and 13. FIG.

(1) Highlight Display FIG. 11 is a flowchart of a process for performing the highlight display described with reference to FIGS. 2 to 4B.

First, the original picture texture (car texture)
Is transferred to the texture storage unit on the VRAM (step S1).

Next, the geometry processing of the car object is performed based on the object data (vertex coordinates, vertex texture coordinates, luminance data, etc.) (step S2). More specifically, for example, after performing a coordinate conversion of the car object from the local coordinate system to the world coordinate system, then performing a coordinate conversion from the world coordinate system to the viewpoint coordinate system, and performing a clipping process, Performs perspective transformation. Then, the object data after the perspective transformation is stored in the main memory and not erased (step S3).

Next, a car object is drawn in a frame buffer based on the object data after the perspective transformation and the original picture texture (car texture) transferred in step S1 (step S4).

Next, the highlighting texture is transferred to the texture storage unit (step S5).

Next, the car object is rotated by a rotation matrix in the highlight direction (projection direction) (step S6). Then, based on the X and Y coordinates of the vertex after rotation,
The U and V coordinates of the highlight texture are calculated (step S7). The calculation formula for calculating the U and V coordinates in this case is as follows, for example.

U = (X / MC) × SX + OFFX (F1) V = (Y / MC) × SY + OFFY (F2) However, when U <0.0, U = 0.0 (F3) U> 1.0 In the case of U = 1.0 (F4) When V <0.0, V = 0.0 (F5) When V> 1.0, V = 1.0 (F6) where X and Y are , The X and Y coordinates of the rotated vertex,
MC is the maximum coordinate value of the car object. Also, S
X and SY are scaling values, and OFFX and OFFY
Is an offset value.

If the scaling values SX, SY = 1.0, the light source is a parallel light source. On the other hand, when the values of SX and SY are reduced, the size of the highlight (or shadow) increases. Therefore, the closer the light source is to the car object, the more S
If the values of X and SY are reduced, the projection by the point light source can be expressed in a pseudo manner.

By changing the offset values OFFX and OFFY, FIGS. 3 (A), (B), 4 (A),
As shown in (B), the highlight (or shadow) can be moved to an arbitrary place.

The texture coordinates in the texture space are specified based on the obtained U and V coordinates, the offset address, the size information of the texture, and the like.

Next, the obtained U and V coordinates are stored in step S
The U and V coordinates of each vertex of the object data (vertex list) stored in the main memory in step 3 are overwritten (step S8). That is, the U and V coordinates set in the model data of the object are replaced with the U and V coordinates calculated in step S7.

Next, based on the object data with the U and V coordinates overwritten in step S8 and the highlight texture transferred in step S5, the object to which the highlight texture is mapped is overwritten in the frame buffer. (Step S9). This makes it possible to generate an image in which the original picture texture and the highlight texture are multi-textured onto the car object.

(2) Shadow Display FIGS. 12 and 13 show FIGS.
It is a flowchart of the process at the time of performing the shadow display demonstrated by (A) -FIG.

First, the texture storage unit of the VRAM is painted with a transparent α value (for example, α = 0.0) (step S10).

Next, geometry processing is performed on the shadow object shown in FIG. 5A in the projection direction (the direction in which the shadow is cast) (step S11). Then, the shadow object after the perspective transformation is drawn in the texture storage unit, and a shadow texture as shown in FIG. 5B is generated (step S12).

Next, the original picture texture (room texture) is transferred to the texture storage unit in the VRAM (step S13).

Next, the geometric processing of the room object is performed (step S14), and the object data after the perspective transformation is stored in the main memory (step S15).

Next, a room object is drawn in the frame buffer based on the object data after the perspective transformation and the original picture texture transferred in step S13 (step S16).

Next, the room object is rotated by a rotation matrix in the shadow dropping direction (projection direction) (step S17). Then, based on the X and Y coordinates of the rotated vertices, the U and V coordinates of the shadow texture are calculated based on the above formulas (F1) to (F6) (step S1).
8).

Next, the obtained U and V coordinates are stored in step S
The U and V coordinates of each vertex of the object data (vertex list) stored in the main memory in step 15 are overwritten and replaced (step S19).

Next, based on the object data in which the U and V coordinates have been overwritten in step S19 and the shadow texture generated in step S12, the object to which the shadow texture is mapped is overwritten in the frame buffer (step S19). S20). This makes it possible to generate an image in which the original picture texture and the shadow texture are subjected to multi-texture mapping on the room object. And finally, a sphere object (a shadow target object)
Is drawn in the frame buffer after the geometry processing (step S21).

4. Hardware Configuration Next, an example of a hardware configuration capable of realizing the present embodiment will be described with reference to FIG.

The main processor 900 has a CD982
(Information storage medium), a program transferred via the communication interface 990, or a program stored in the ROM 950 (one of the information storage media).
Various processes such as sound processing are executed.

The coprocessor 902 assists the processing of the main processor 900, has a multiply-accumulate unit and a divider capable of high-speed parallel operation, and executes a matrix operation (vector operation) at high speed. For example, when a physical simulation for moving or moving an object requires processing such as matrix operation, a program operating on the main processor 900 instructs the coprocessor 902 to perform the processing (request ).

The geometry processor 904 performs geometry processing such as coordinate transformation, perspective transformation, light source calculation, and curved surface generation. The geometry processor 904 includes a multiply-accumulate unit and a divider capable of high-speed parallel computation, and performs matrix computation (vector computation). Calculation) at high speed. For example, when performing processing such as coordinate transformation, perspective transformation, and light source calculation, a program operating on the main processor 900 instructs the geometry processor 904 to perform the processing.

The data decompression processor 906 performs a decoding process for decompressing the compressed image data and sound data, and performs a process for accelerating the decoding process of the main processor 900. As a result, a moving image compressed by the MPEG method or the like can be displayed on an opening screen, an intermission screen, an ending screen, a game screen, or the like. The image data and sound data to be decoded are stored in the ROM 950,
It is stored on a CD 982 or transferred from outside via a communication interface 990.

The drawing processor 910 executes a high-speed drawing (rendering) process of an object composed of primitive surfaces such as polygons and curved surfaces. When drawing an object, the main processor 900
Uses the function of the DMA controller 970 to pass object data to the drawing processor 910,
If necessary, the texture is transferred to the texture storage unit 924. Then, the drawing processor 910 draws the object in the frame buffer 922 at high speed while performing hidden surface removal using a Z buffer or the like based on the object data and the texture. Further, the drawing processor 910 includes α blending (semi-transparent processing), mip mapping, fog processing, trilinear
Filtering, anti-aliasing, shading, and the like can also be performed. Then, when an image for one frame is written to the frame buffer 922, the image is displayed on the display 912.

The sound processor 930 includes a multi-channel ADPCM sound source or the like, and generates high-quality game sounds such as BGM, sound effects, and voices. The generated game sound is output from the speaker 932.

Operation data from the game controller 942, save data and personal data from the memory card 944 are transferred via the serial interface 940.

A ROM 950 stores a system program and the like. In the case of the arcade game system, the ROM 950 functions as an information storage medium,
Various programs are stored in 950. Note that a hard disk may be used instead of the ROM 950.

The RAM 960 is used as a work area for various processors.

[0113] The DMA controller 970 provides a DM between the processor and the memory (RAM, VRAM, ROM, etc.).
A transfer is controlled.

A CD drive 980 stores a CD 982 in which programs, image data, sound data, and the like are stored.
(Information storage medium) to enable access to these programs and data.

The communication interface 990 is an interface for transferring data to and from the outside via a network. In this case, a network connected to the communication interface 990 may be a communication line (analog telephone line, ISDN), a high-speed serial bus, or the like. Then, data can be transferred via the Internet by using a communication line. Further, by using the high-speed serial bus, data transfer between another image generation system and another game system becomes possible.

The means of the present invention may be entirely executed by hardware only, or executed only by a program stored in an information storage medium or a program distributed via a communication interface. Is also good. Alternatively, it may be executed by both hardware and a program.

When each means of the present invention is executed by both hardware and a program, the information storage medium stores a program (program, program, program) for executing each means of the present invention using hardware. Data) will be stored. More specifically, the above program
Each processor 902, 904, 90 which is hardware
6, 910, 930, etc., and instruct the processing, and if necessary, pass the data. Then, each processor 902, 9
04, 906, 910, 930, etc. execute the respective means of the present invention based on the instruction and the passed data.

FIG. 15A shows an example in which the present embodiment is applied to an arcade game system. The player enjoys the game by operating the lever 1102, the button 1104, and the like while watching the game image projected on the display 1100. Various processors, various memories, and the like are mounted on a built-in system board (circuit board) 1106. A program (or a program or data) for executing each unit of the present invention is stored in the memory 11 serving as an information storage medium on the system board 1106.
08 is stored. Hereinafter, this information is referred to as storage information.

FIG. 15B shows an example in which the present embodiment is applied to a home game system. The player enjoys the game by operating the game controllers 1202 and 1204 while watching the game image projected on the display 1200. In this case, the storage information is stored in a CD 1206 or a memory card 1208, 1209, which is an information storage medium detachable from the main system.

FIG. 15C shows a host device 1300,
The host device 1300 and the network 1302 (LA
N or a wide area network such as the Internet).
An example in which the present embodiment is applied to a system including 4-1 to 1304-n will be described. In this case, the storage information is, for example, a magnetic disk device that can be controlled by the host device 1300,
It is stored in an information storage medium 1306 such as a magnetic tape device and a memory. If the terminals 1304-1 to 1304-n are capable of generating a game image and a game sound in a stand-alone manner, the host device 1300 outputs the game image and the game sound.
A game program or the like for generating a game sound is transmitted to the terminal 1.
It is delivered to 304-1 to 1304-n. On the other hand, if it cannot be generated stand-alone, the host device 1300 generates a game image and a game sound, and transmits them to the terminals 1304-1 to 1304-1.
1304-n and output at the terminal.

In the case of the configuration shown in FIG. 15C, each means of the present invention may be executed by distributing between a host device (server) and a terminal. Further, the storage information for executing each means of the present invention may be stored separately in an information storage medium of a host device (server) and an information storage medium of a terminal.

The terminal connected to the network may be a home game system or an arcade game system. When the arcade game system is connected to a network, a portable information storage device capable of exchanging information with the arcade game system and exchanging information with the home game system. (Memory card, portable game device) is desirable.

The present invention is not limited to those described in the above embodiments, and various modifications can be made.

For example, in the invention according to the dependent claims of the present invention, a configuration in which some of the constituent elements of the dependent claims are omitted may be adopted. In addition, a main part of the invention according to one independent claim of the present invention may be made dependent on another independent claim.

Further, the projection texture used in the present invention is not limited to a highlight texture, a shadow texture and the like. For example, various modifications can be made, such as a texture representing a liquid as described in FIGS. 8A to 8D and a texture representing a car cover as described in FIGS. 9A and 9B. is there.

It is particularly desirable that the projection of the object is a parallel projection, but the invention is not limited to this.

Further, the texture mapped to the object is not limited to the texture of the color information, but may be luminance information, translucent information (α value), surface shape information (bump value),
Textures for reflectance information, refractive index information, depth information, and the like may be used.

The multi-texture mapping is 1
It may be realized by overlapping a plurality of textures on one object (multi-texture mapping in a narrow sense), or by overwriting a plurality of objects to which different textures are mapped. When a plurality of textures are superimposed on one object, the object data includes a plurality of texture coordinates such as texture coordinates for designating a first texture and texture coordinates for designating a second texture. What is necessary is just to include the texture coordinate of a set.

The present invention also includes various games other than racing games (fighting games, shooting games, robot battle games, sports games, competition games, role playing games, music playing games, dance games, etc.).
Applicable to

The present invention also provides various images such as a business game system, a home game system, a large attraction system in which many players participate, a simulator, a multimedia terminal, an image generation system, and a system board for generating game images. Applicable to generation systems.

[Brief description of the drawings]

FIG. 1 is an example of a block diagram of an image generation system according to an embodiment.

FIG. 2 is a diagram for explaining a method of the present embodiment.

FIGS. 3A and 3B are examples of images generated according to the embodiment; FIGS.

FIGS. 4A and 4B are also examples of images generated according to the present embodiment.

FIGS. 5A, 5B, and 5C are diagrams illustrating examples of a shadow object, a shadow texture, and a room object.

FIGS. 6A and 6B are diagrams illustrating an example of a shadow display realized by the present embodiment.

FIG. 7 is a diagram illustrating an example of a shadow display realized by the embodiment.

FIGS. 8A to 8D are diagrams for explaining a method of expressing a cup containing a liquid.

FIGS. 9A and 9B are diagrams for explaining a method of expressing a car with a cover.

FIG. 10 is a diagram for describing a method of realizing multi-texture mapping by overlappingly drawing a plurality of objects to which different textures are mapped.

FIG. 11 is a flowchart illustrating a detailed processing example of the present embodiment.

FIG. 12 is a flowchart illustrating a detailed processing example of the present embodiment.

FIG. 13 is a flowchart illustrating a detailed processing example of the present embodiment.

FIG. 14 is a diagram illustrating an example of a hardware configuration capable of realizing the present embodiment.

FIGS. 15A, 15B, and 15C are diagrams showing examples of various types of systems to which the present embodiment is applied; FIGS.

[Explanation of symbols]

 Reference Signs List 10 car object 12 virtual camera 20 highlight texture 22, 24 area 30 highlight 40 shadow object 42 shadow texture 50 room object 52 sphere object 54 shadow 100 processing unit 110 game processing unit 130 image generation unit 132 geometry processing unit 134 texture Coordinate calculation unit 140 Drawing unit 142 Texture mapping unit 150 Sound generation unit 160 Operation unit 170 Storage unit 172 Main memory 174 Frame buffer 176 Texture storage unit 180 Information storage medium 190 Display unit 192 Sound output unit 194 Portable information storage device 196 Communication unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G06F 15/72 465 F-term (Reference) 2C001 AA09 BA00 BA02 BA05 BC00 BC06 CB01 CB06 CC02 CC08 5B050 AA09 BA08 BA09 BA11 EA27 EA30 FA02 FA06 5B080 BA04 FA08 GA22

Claims (14)

[Claims] 1. An image generation system for generating an image, comprising: projecting a vertex of a first object in a given projection direction;
Texture coordinate calculating means for calculating first and second texture coordinates of the projected texture based on the first and second coordinates of the vertices obtained by projection; and an original picture texture of the first object. The projection texture specified by the first and second texture coordinates is mapped to a first object, and a drawing means for drawing the first object, and an image viewed from a virtual camera in an object space is generated. Means, and an image generation system comprising: 2. The method according to claim 1, wherein the texture coordinate calculation unit calculates an offset value or a scaling value when calculating the first and second texture coordinates from the first and second coordinates.
Alternatively, an image generation system wherein the projection direction is changed in real time. 3. The image generation system according to claim 1, wherein the projection texture is a highlight texture for highlighting the first object. 4. The image generation system according to claim 1, wherein the projection texture is a shadow texture for casting a shadow of a second object on a first object. 5. The image generation system according to claim 4, wherein the shadow texture is generated by performing a geometry process on the second object. 6. The first and second coordinates of a vertex obtained by rotating a vertex of a first object by a given rotation matrix, wherein the texture coordinate calculating means is configured to rotate the vertex of the first object by a given rotation matrix. An image generation system for calculating first and second texture coordinates of a projected texture based on the first and second texture coordinates. 7. The method according to claim 1, wherein the drawing means draws a first object based on object data of the first object and an original picture texture, and the texture coordinate calculation means Replacing the first and second texture coordinates of the original picture texture included in the object data of the first object with the first and second texture coordinates of the calculated projected texture; An image generating system, wherein a first object is drawn based on object data in which second texture coordinates have been replaced and the projected texture. 8. A computer-usable information storage medium for projecting vertices of a first object in a given projection direction.
Texture coordinate calculating means for calculating first and second texture coordinates of the projected texture based on the first and second coordinates of the vertices obtained by projection; and an original picture texture of the first object. The projection texture specified by the first and second texture coordinates is mapped to a first object, and a drawing means for drawing the first object, and an image viewed from a virtual camera in an object space is generated. An information storage medium comprising: means; and a program for executing: 9. The method according to claim 8, wherein the texture coordinate calculation unit calculates an offset value or a scaling value when calculating the first and second texture coordinates from the first and second coordinates.
Alternatively, an information storage medium characterized by changing a projection direction in real time. 10. The information storage medium according to claim 8, wherein the projection texture is a highlight texture for highlight-displaying the first object. 11. The information storage medium according to claim 8, wherein the projection texture is a shadow texture for casting a shadow of a second object on a first object. 12. The information storage medium according to claim 11, wherein the shadow texture is generated by performing a geometry process on the second object. 13. The first and second coordinates of the vertices obtained by rotating the vertices of the first object by a given rotation matrix, according to claim 8, An information storage medium for calculating first and second texture coordinates of a projected texture based on the first and second texture coordinates. 14. The method according to claim 8, wherein the drawing means draws a first object based on object data of the first object and an original picture texture, and the texture coordinate calculation means Replacing the first and second texture coordinates of the original picture texture included in the object data of the first object with the first and second texture coordinates of the calculated projected texture; An information storage medium for drawing a first object based on object data in which second texture coordinates have been replaced and the projected texture.