JP2002216155A - Image generation system, program and information storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image generation system, a program and an information processing medium capable of generating a realistic and sightly image with a small processing load when the image is generated by using particles. SOLUTION: A particle load relief processing part 134 performs a processing to change at least one of the number of particle generating points, the number of particles and life of particles based on information regarding the processing load. In addition, a depth queuing processing is performed to a reference color of particle set objects based on depth information of the particle generating points and a depth queuing effect is applied to the respective particles belonging to a particle set by using a base color. In addition, the number of division of primitives to constitute the particle object is controlled based on at least one of the depth information of the particle object, positional relation to a virtual camera and a rate of plotting area to occupy a picture of the primitive to constitute the particle object.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, there has been known a game system for generating an image which can be viewed from a given viewpoint in an object space which is a virtual three-dimensional space. Popular as something you can do.

[0003] In such a game system, generating a more realistic image is an important technical problem in order to improve the virtual reality of the player. Here, for example, when there are splashes or the like occurring in the game space, it is important to express realistic splashes.

A technique called a particle system is known as a technique for expressing such splashes and the like. That is, some natural objects are convenient to express as a collection of fine particles that are difficult to identify one by one. For example, steam and fog, plume, earth smoke, flickering flames, explosions, fountains and waterfalls, bubbles and splashes, fireworks, flying powder, falling rain and snow, haze, swirls and tornadoes, cherry blossoms flying in the wind, etc. can give.

In a particle system, not only the shape is unstable but also a model of an object or a phenomenon in which a clear surface does not exist is expressed as a movement of a large number of particles, and such particles are called particles. .

[0006] Here, particles have characteristics such as color and lifetime, and are generated, moved, and moved by a given rule (given by the emitter) and an acting force (force).
Disappear. In addition, particle positions in each frame are calculated based on fluid and collision calculations based on emitters and forces.
This is determined by performing an operation for determining the position of the particle in the three-dimensional space, such as a motion calculation.

[0007] When such particles are used to represent splashes and the like, a realistic image of splashes and the like can be generated.

However, when an image such as a splash is generated by using such particles, there is a disadvantage that the processing load becomes unduly heavy.

For example, in order to generate a realistic and good-looking splash image, it is preferable that the number of particles emitted per unit time is larger. However, there is a problem that various processes required for image generation in which the number of particles increases increase.

[0010] Particularly in a game system that requires real-time image generation with limited hardware resources, when generating an image using particles, how to generate a realistic and good-looking image with a small processing load Is a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object of the present invention is to generate a real and good-looking image with a small processing load when generating an image using particles. An object of the present invention is to provide an image generation system, a program, and an information storage medium that can be generated.

[0012]

(1) The present invention relates to a system for generating an image, wherein at least one of the number of particle generation points, the number of particles, and the life of the particles is determined based on information on a processing load at the time of image generation. And means for generating an image that can be viewed from a given viewpoint in the object space using the particles.

[0013] A program according to the present invention is a program usable by a computer (a program embodied in an information storage medium or a carrier wave), and is characterized by causing the computer to realize the above means. Further, an information storage medium according to the present invention is characterized by including an information storage medium usable by a computer and a program for causing a computer to realize the above means.

The information on the processing load at the time of image generation is
For example, refresh rate, global clock, CP
The drawing speed per frame is given by a given value that can be determined, such as a U clock. Here, the processing load at the time of image generation may be a calculation load performed by the CPU or a calculation load generated by the drawing chip, and includes various processing loads required for image generation.

The life of a particle is given, for example, as characteristic information of the particle, and may be given, for example, in the form of an α value when performing translucent drawing.

According to the present invention, when it is determined that the processing load is high, the number of particle generation points can be reduced,
By reducing the number of particles or shortening the life of the particles, it is possible to reduce the processing load and prevent the processing from dropping.

(2) The image generation system, program and information storage medium according to the present invention are characterized in that the number of particles is the number of particles existing on one screen or the number of particles generated from a given generation point. And

(3) The image generation system, the program, and the information storage medium according to the present invention reduce the processing load by shortening the life of a particle farther from the virtual camera based on the depth information of the particle. It is characterized by the following.

By setting the life of the particles to be short, the particles can be quickly eliminated, and the processing load can be reduced accordingly.

Here, the farther the particle is, the less the visual effect is, so it is preferable to shorten the life of the particle preferentially over the particle farthest from the virtual camera based on the depth information of the particle.

As described above, according to the present invention, it is possible to select, based on the depth information of a particle, one that has a small effect on the appearance even if its life is shortened. Can be reduced.

(4) The image generation system, the program, and the information storage medium according to the present invention generate an image preferentially from a particle set generated from a particle generation point distant from the virtual camera based on depth information of the particle generation point. , The processing load is reduced.

By excluding a set of particles generated from a particle generation point from the object of image generation, the processing load can be reduced accordingly.

In this case, since the image generation of the particle set generated from the particle generation point located far away is less affected by the appearance, the generation of the particle set from the particle generation point located far from the virtual camera is based on the depth information of the particle generation point. It is preferable to preferentially exclude the generated particle set from the object of image generation.

As described above, according to the present invention, based on the depth information of the particles, it is possible to select an image which has little effect on the appearance even if it is not the object of image generation and exclude it from the object of image generation. Can be kept at a maximum, and the processing load can be reduced.

(5) The image generation system, the program and the information storage medium according to the present invention reduce the number of particles to be preferentially generated from a particle generation point distant from the virtual camera based on depth information of the particle generation point. By doing so, the processing load is reduced.

The processing load can be reduced by reducing the number of particles generated from the particle generation point.

Here, since reducing the number of particles generated from the particle generation point located far away has less of a visual effect, priority is given to the particle generation point located far from the virtual camera based on the depth information of the particle generation point. It is preferable to reduce the number of generated particles.

As described above, according to the present invention, it is possible to reduce the number of particles to be generated by selecting an object which is not visually affected even if it is not targeted for image generation based on the depth information of the particle generation point. The processing effect can be reduced while keeping the appearance effect to the maximum.

(6) The image generation system, the program and the information storage medium according to the present invention reduce the precision of an object by giving priority to an object assigned to a particle distant from the virtual camera based on the depth information of the particle. It is characterized in that the processing load is reduced.

Decreasing the precision of an object refers to, for example, a case of using a simpler model. According to the present invention, LOD (level of detail) can be performed on an object to be assigned to a particle based on the depth information of the particle, so that the visual effect can be kept at a maximum and the processing load can be reduced.

(7) The image generation system, the program, and the information storage medium according to the present invention are arranged such that, based on depth information of a particle generation point, an object is assigned priority over an object assigned to a particle generated from a particle generation point distant from the virtual camera. The processing load is reduced by reducing the precision of the processing.

[0033] Decreasing the precision of an object refers to, for example, a case of using a simpler model. According to the present invention, the LOD of an object assigned to a particle is determined based on the depth information of the particle generation point.
Since (level of detail) can be performed, the effect of appearance can be kept at a maximum, and the processing load can be reduced.

(8) The present invention relates to a system for generating an image, wherein when the transparency given to a particle or an object assigned to the particle becomes smaller than a predetermined value, the particle or the object assigned to the particle is deleted. It is characterized by including means for excluding from an object of image generation, and means for generating an image viewed from a given viewpoint in an object space using particles.

A program according to the present invention is a program usable by a computer (a program embodied in an information storage medium or a carrier wave), and is characterized by causing the computer to realize the above means. Further, an information storage medium according to the present invention is characterized by including an information storage medium usable by a computer and a program for causing a computer to realize the above means.

This is effective when the transparency given to a particle (or an object assigned to the particle) changes with the passage of time from the generation of the particle. Here, the transparency is given, for example, as an α value when performing a translucent drawing process.

When the transparency given to the particles or the objects assigned to the particles becomes smaller than a predetermined value, the particles or the objects assigned to the particles are excluded from the object of image generation, for example, for image generation. It is possible to omit various processes related to image generation, such as a position calculation process, a coordinate conversion process, a rendering process, and other subsequent processes, which can reduce the processing load.

(9) The present invention relates to a system for generating an image, wherein means for performing a process of extinguishing a particle or an object assigned to the particle when the height of the particle reaches a predetermined value, and an object space using the particle. Means for generating an image that can be viewed from a given viewpoint.

A program according to the present invention is a program usable by a computer (a program embodied in an information storage medium or a carrier wave), and is characterized in that the above means is realized by a computer. Further, an information storage medium according to the present invention is characterized by including an information storage medium usable by a computer and a program for causing a computer to realize the above means.

According to the present invention, for example, when the height of the splash generated by using the particles becomes the height of the water surface, or when the height of the snow or the like generated by using the particles becomes the height of the ground. Splashes and snow can be eliminated.

As described above, when the height of a particle reaches a predetermined value, the particle or the object assigned to the particle is annihilated, so that subsequent processing on the particle can be omitted, so that the processing load can be reduced. .

Since it is possible to determine whether or not to perform the annihilation process based on the height of the particles, the processing load required for the determination can be reduced. Therefore, it is effective when the state where the particle goes out of the visible range due to the height of the particle occurs.

(10) Further, in the image generation system, the program and the information storage medium according to the present invention, the erasing process includes a case where particles or objects assigned to the particles disappear after a lapse of a predetermined time. .

(11) The present invention relates to a system for generating an image, in which it is determined whether or not there is an object that blocks the field of view based on depth information of the particle. Alternatively, the method includes a means for excluding an object assigned to a particle from a target of image generation, and a means for generating an image viewed from a given viewpoint in an object space using the particle.

A program according to the present invention is a program usable by a computer (a program embodied in an information storage medium or a carrier wave), and is characterized by causing the computer to realize the above means. Further, an information storage medium according to the present invention is characterized by including an information storage medium usable by a computer and a program for causing a computer to realize the above means.

For example, when the splash is hidden by other objects, the drawing process of the splash can be omitted, so that the processing load can be reduced.

(12) The present invention relates to a system for generating an image, wherein a depth of a particle generation point with respect to a reference color set for a particle set object represented by a particle set generated from the same particle generation point. Means for performing a depth skew process based on the information, and a color obtained by the depth skew process as a base color of the particle aggregate object,
Means for performing an image generation process by applying a depth skew effect using the base color to each particle belonging to a particle set generated from the same particle generation point.

Further, a program according to the present invention is a program usable by a computer (a program embodied in an information storage medium or a carrier wave), and is characterized by causing the computer to realize the above means. Further, an information storage medium according to the present invention is characterized by including an information storage medium usable by a computer and a program for causing a computer to realize the above means.

In general, when depth queuing processing is performed on a polygon object, for each vertex, the vertex color and the background color are synthesized according to the depth value of the vertex, and the vertex color is synthesized according to the depth value. To change. For this reason, the depth queuing process is required for each vertex of each particle object constituting the particle aggregate object, so that the processing load is significantly increased.

However, according to the present invention, the depth squeezing process is performed based on the depth information of the particle generation point with respect to the reference color set for the particle set object represented by the particle set generated from the same particle generation point. Then, the obtained color is used as the base color of the particle set object, and an image is generated by applying the depth skew effect to each particle belonging to the particle set generated from the same particle generation point using the base color. Perform processing.

For this reason, the calculation for obtaining the base color for one particle set object is required only once. The FOG effect can be achieved with a much smaller processing load than when a vertex color that changes by the depth skewing process is calculated for each particle or all vertices of the particle object constituting the particle aggregate object.

(13) The present invention relates to a system for generating an image, wherein a particle is based on at least one of depth information of a particle object, a positional relationship with respect to a virtual camera, and a ratio of a drawing area of a primitive constituting the particle object to a screen. Means for controlling the number of divisions of primitives constituting the object,
Means for generating an image viewed from a given viewpoint in the object space using the particles.

A program according to the present invention is a program usable by a computer (a program embodied in an information storage medium or a carrier wave), and is characterized in that the above means is realized by a computer. Further, an information storage medium according to the present invention is characterized by including an information storage medium usable by a computer and a program for causing a computer to realize the above means.

Here, the primitive is a polygon, a sprite, or the like.

When the depth information of the particle object or the distance from the virtual camera increases, control is preferably performed so that the number of divisions of primitives constituting the particle object increases.

In general, when an image is generated using hardware having a limited memory resource, a large primitive is drawn in the VRAM (frame buffer) because the actual storage area of the VRAM (frame buffer) is limited. If this is attempted, paging occurs during the rendering of the primitive, and the processing load and processing time increase.

According to the present invention, when the depth information of the particle object or the distance from the virtual camera increases, the number of divisions of the primitives constituting the particle object can be increased, so that paging can be performed during the drawing of the primitives. This can be prevented from occurring, and the processing load and processing time can be reduced.

(14) The image generation system, the program, and the information storage medium according to the present invention increase the number of divisions of the primitives constituting the particle object when the depth information of the particle object or the distance from the virtual camera increases. It is characterized by doing.

(15) The image generation system, the program and the information storage medium according to the present invention divide the primitives constituting the particles when the ratio of the drawing area of the primitives constituting the particle object to the screen increases. It is characterized in that the number is increased.

(16) The image generation system, the program and the information storage medium according to the present invention are characterized in that the number of divisions is increased by subdividing primitives assigned to particles.

[0061]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

1. Configuration FIG. 1 shows an example of a block diagram of an image generation system (game system) of the present embodiment. In this figure, this 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, the storage unit 170, and the information storage medium 180), and other blocks. (For example, the operation unit 160 and the display unit 19
0, the sound output unit 192, the portable information storage device 194, and the communication unit 196) can be optional components.

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

The operation section 160 is for the 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 usable 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 (program or data) for executing the means of the present invention (the present embodiment) (particularly, the blocks included in the processing unit 100).

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 an instruction thereof. At least one of information for performing the processing according to the above.

The display section 190 outputs an image generated according to the present embodiment.
LCD or HMD (head mounted 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. 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 the outside (for example, a host device or another game system), and has a function of various processors or an ASIC for communication. This can be realized by hardware, a program, or the like.

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 such an information storage medium of the 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 120, and a sound generation section 150.

Here, the game processing section 110 includes a coin (price) receiving process, various mode setting processes, a game progress process, a selection screen setting process, a hit check process,
Various game processes such as a process of calculating a game result (results and results), a process for a plurality of players to play in a common game space, and a game over process are performed using operation data from the operation unit 160, Information storage device 19
4 based on personal data, saved data, game programs, and the like.

The image generation unit 120 includes a game processing unit 110
Various image processing is performed in accordance with an instruction or the like from, for example, a process of generating an image viewed from a virtual camera (viewpoint) in the object space and outputting the generated image to the display unit 190.

For example, the image generation unit 120 obtains the position and rotation angle (rotation angle about the X, Y or Z axis) of the object (one or more primitive surfaces), processes the object (motion process), A process for obtaining a position (the position of the virtual camera) and a line-of-sight angle (a rotation angle of the virtual camera) and a process for arranging an object such as a map object in the object space are performed.

For example, the image generation unit 120 performs various types of geometric processing such as coordinate conversion from the local coordinate system to the world coordinate system, coordinate conversion from the world coordinate system to the viewpoint coordinate system, perspective conversion to the screen coordinate system, clipping, and the like. (Three-dimensional operation). Then, the drawing data (position coordinates, texture coordinates, color (luminance) data, α value, etc., of the definition points of the two-dimensional primitive surface) obtained by the geometry processing are stored in the main memory 172 of the storage unit 170. , Will be saved.

Further, for example, the image generating section 120 performs texture mapping, color (luminance) data interpolation processing, hidden surface elimination, and the like based on the drawing data obtained by the geometry processing and stored in the main memory 172. The primitive side of frame buffer 174
Perform processing to draw on This gives a given viewpoint (virtual camera) in the object space where the object is located
Is generated.

Further, for example, the image generating section 120 performs a process of sequentially generating, moving, or extinguishing particles with the passage of time. More specifically, a process of randomly changing the generation amount, generation position, moving state (speed, acceleration, etc.) or life of the particles (virtual light source primitive) is performed. As a result, irregularly-shaped display objects such as splashes can be realistically expressed.

The image generating unit 120 includes at least one of a drawing order determining processing unit 130, a particle inflating processing unit 132, and a particle load reducing processing unit 134.

The drawing order determination processing unit 130 determines the necessity of a sorting process for determining the drawing order of a plurality of translucent primitives based on given conditions;
When it is determined that the sorting process is necessary, the sorting process of the plurality of translucent primitives is performed, and the drawing order of the plurality of translucent primitives is determined based on the processing result of the sorting process, and it is determined that the sorting process is not necessary. In this case, a process for determining the drawing order of the translucent primitives may be performed based on the result of the previous sorting process.

The drawing order determination processing unit 130 determines the necessity of a sorting process for determining the drawing order of a plurality of translucent primitive sets based on given conditions, and determines that the sorting process is necessary. If it is determined, the sorting process is performed for each semi-transparent primitive set based on the representative position of the plurality of semi-transparent primitive sets, and the drawing order of the plurality of semi-transparent primitive sets is determined based on the processing result of the sorting process. If it is determined that is not necessary, a process of determining the drawing order of the semi-transparent primitive set based on the previous sorting processing result may be performed.

The drawing order determination processing unit 130 determines the necessity of a sorting process for determining the drawing order of a particle set object represented by a particle set generated from a plurality of particle generation points based on given conditions. Processing, and when it is determined that sorting processing is necessary, the sorting processing of the particle aggregation object is performed based on the depth information of the plurality of particle generation points, and the drawing order of the particle aggregation object is determined based on the processing result of the sorting processing. If it is determined that the sorting process is not necessary, a process of determining the drawing order of the particle aggregate object based on the processing result of the previous sorting process may be performed.

An image generation system characterized in that the drawing order determination processing unit 130 determines whether or not the predetermined condition is satisfied based on at least one of the position and the rotation of the virtual camera.

The drawing order determination processing unit 130 may determine whether the predetermined condition is satisfied based on at least one of the position and the rotation of the character object.

[0086] The drawing order determination processing unit 130 sets in advance an area that requires a sorting process.
Whether or not the predetermined condition is satisfied may be determined based on whether or not at least one of the virtual camera and the character object is in the area requiring sorting.

The area in which the sorting process is required is performed when at least one of the virtual camera and the character object moves in the area, and the context of the plurality of translucent primitives, the translucent primitive set, or the point at which particles are generated with respect to the virtual camera. It is preferable to set the area to be likely to change.

The area requiring the sorting process is expressed by a semi-transparent primitive, a set of semi-transparent primitives, or particles generated from a particle generation point when at least one of the virtual camera and the character object is present in the area. It may be an area where a state where no object is displayed occurs.

The rendering order determination processing unit 130 may sort the plurality of translucent primitive sets based on the depth information of the representative points, and determine the rendering order for each translucent primitive set.

The drawing order determination processing unit 130 sorts a plurality of particle aggregate objects expressed by a particle aggregate generated from a given generation point based on depth information of the generation point, and determines the rendering order of the particle aggregate objects. May be performed.

The particle inflating processing section 132 sets a particle given to the three-dimensional space as a parent particle, calculates coordinates of an inflating point to be generated based on the position coordinates of the parent particle, and generates a child particle at the inflating point. May be performed.

Further, the particle inflating processing section 132
A process of calculating the coordinates of a padding point to be generated on the screen plane based on the position coordinates of the parent particle which is perspectively transformed to the screen plane, using the particle given to the three-dimensional space as a parent particle; A process of generating particles may be performed.

The child particles generated by inflating may inherit the characteristic information of the parent particles.

The particle inflating processing section 132
The position of the padding point generated in consideration of the depth information of the parent particle may be determined.

The particle inflating processing section 132
The position of the padding point generated in consideration of the information indicating the time or the progress of the frame may be determined.

The particle inflating processing unit 132
The number of child particles generated by padding may be controlled in consideration of information indicating the progress of time or frame.

The particle inflating processing section 132
The size of the object to be assigned to the child particle may be determined based on the depth information of the parent particle.

The particle inflating processing section 132
The size of the object assigned to the child particle may be changed according to the passage of time or frame.

The particle inflating processing section 132
A process of generating a given child particle generated at the (n + 1) th frame for a given parent particle at a position having continuity with a given child particle generated at the nth frame for the same parent particle is performed. You may do so.

The particle inflating processing section 132
n th frame position information of a given parent particle (x _n, y _n) n frames based on the position information obtained by applying the function f _x1, f _y1 relative _{(x n ', y n'} ) When the position of a given child particle of the eye is determined, the position information (x _{n + 1} , y) of the same parent particle in the ( _{n + 1) th} frame
_The position of a given child particle in the ( _{n + 1} ) th frame is determined based on position information ( _{xn + 1} ', yn _{+ 1} ') obtained by applying functions _fx1 and _fy1 to ( _{n + 1} ). You may make it.

Further, the particle inflating processing unit 132
When a plurality of child particles including a first child particle and a second child particle are generated for a given parent particle, the positions at which the first child particle and the second child particle are generated have different functions. You may make it determine based on the positional information obtained by applying.

The particle inflating processing section 132
The number of child particles generated by padding may be controlled according to the depth information of the parent particle or the depth information of the particle generation point.

Further, the particle inflating processing unit 132
The number of child particles to be inflated and generated may be controlled based on the information on the processing load at the time of generating the image.

The particle load reduction processing section 134 may perform processing for changing at least one of the number of particle generation points, the number of particles, and the life of the particles based on information on the processing load at the time of image generation.

The number of particles may be the number of particles existing on one screen or the number of particles generated from a given generation point.

The particle load reduction processing section 134
The processing load may be reduced by preferentially shortening the lifetime of particles far from the virtual camera based on the depth information of the particles.

The particle load reduction processing section 134
The processing load may be reduced by preferentially excluding a set of particles generated from a particle generation point distant from the virtual camera on the basis of depth information of the particle generation point and excluding them from image generation.

The particle load reduction processing section 134 reduces the processing load by reducing the number of particles generated preferentially from the particle generation point distant from the virtual camera based on the depth information of the particle generation point. May be.

The particle load reduction processing unit 134
Alternatively, the processing load may be reduced by lowering the precision of the object preferentially to the object assigned to the particle far from the virtual camera based on the depth information of the particle.

The particle load reduction processing section 134
Alternatively, the processing load may be reduced by lowering the precision of an object preferentially to an object assigned to a particle generated from a particle generation point distant from the virtual camera based on depth information of the particle generation point.

When the transparency given to the particle or the object assigned to the particle becomes smaller than a predetermined value, the particle load reduction processing unit 134 excludes the particle or the object assigned to the particle from the object of image generation. Processing may be performed.

Further, the particle load reduction processing section 134
When the height of the particle reaches a predetermined value, the process of deleting the particle or the object assigned to the particle may be performed.

It is preferable that the disappearing process includes a case where the particles or the objects assigned to the particles disappear after a predetermined time has elapsed.

The particle load reduction processing section 134
Determines whether there is an object that blocks the field of view based on the depth information of the particle, and if there is an object that blocks the field of view, performs a process of excluding the particle or the object assigned to the particle from the image generation target. It may be performed.

The particle load reduction processing section 134
Performs a depth skewing process based on depth information of a particle generation point with respect to a reference color set for a particle collection object expressed by a particle set generated from the same particle generation point, and The obtained color may be used as the base color of the particle set object, and the depth skewing effect may be applied to each particle belonging to the particle set generated from the same particle generation point using the base color.

The particle load reduction processing section 134
Performs a process of controlling the number of divisions of a primitive constituting a particle object based on at least one of depth information of the particle object, a positional relationship to a virtual camera, and a ratio of a drawing area of a primitive constituting the particle object to a screen. May be.

The particle load reduction processing section 134
May be such that when the depth information of the particle object or the distance from the virtual camera increases, the number of divisions of the primitives constituting the particle object may be increased.

The particle load reduction processing section 134
When the ratio of the drawing area occupied by the primitives constituting the particle object to the screen increases, the number of divisions of the primitives constituting the particle may be increased.

The particle load reduction processing section 134
May increase the number of divisions by subdividing primitives assigned to particles.

The sound generation unit 150 performs various sound processes according to instructions from the game processing unit 110, and performs BGM,
A sound such as a sound effect or a voice is generated and output to the sound output unit 192.

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

Note that the game system according to the present embodiment
A system dedicated to the single player mode in which only a single player can play may be provided, or a system provided with not only such a single player mode but also a multi-player mode in which a plurality of players can play.

When a plurality of players play,
The game images and game sounds 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.

[0124] 2. FIG. 2 illustrates an example of a game image generated by the image generation device according to the present embodiment. In the present embodiment, a splash image as shown in the figure is generated using a particle system.

Hereinafter, each feature of the present invention will be described by taking as an example a case where an image of a splash is generated by the image generating apparatus of the present embodiment using a particle system.

(1) Processing Flow FIGS. 3 and 4 are flowcharts for explaining the overall processing flow when generating an image of a splash by the image generating apparatus of the present embodiment.

The processes shown in FIGS. 3 and 4 are performed by the image generation unit (130 in FIG. 1). Here, it is assumed that the image generation unit includes, for example, a CPU and a drawing unit (a dedicated chip for generating an image).

The steps S10 to S30 in FIG.
This is a process performed by U for each particle generation point.

First, based on the depth information of a plurality of splashing points, a process for determining a drawing order for each point is performed (step S10). In the present embodiment, since a translucent object is assigned to the particles that make up the splash, it is necessary to perform translucent drawing on the frame buffer first from the generation point far from the virtual camera in order to perform accurate drawing. For this reason, in the present embodiment, a process for determining the drawing order for each occurrence point is performed.

Here, in the present embodiment, the necessity of the sorting process based on the position of the character object (virtual camera) in each frame is determined instead of performing the sorting process at a plurality of occurrence points unconditionally for each frame. Judgment is made, and sorting processing is omitted when unnecessary, thereby speeding up the processing. (Refer to (2) Drawing order determination processing for details).

Next, various parameters are set (step S20).

For example, processing to determine the base color of each particle aggregate object for each generation point (for details, refer to (5) Reduction of FOG effect processing), processing to determine the number of particles generated from each generation point, A process for determining characteristics of each particle (particularly, information on transparency and life) is performed (for details, refer to (4) Process for reducing processing load).

Then, based on the determined drawing order, the data is transferred to the drawing unit from the data of the particle generation point at the back (step 30).

Steps S40 to S90 in FIG. 4 are mainly performed by the vector unit for each particle.

First, the transparency of the particles is reduced based on the frame number. When the transparency becomes negative, the processing is terminated. In addition, the size of the sprite (single polygon) assigned to the particle based on the frame number is increased (step S40).

Next, based on the frame number, the position coordinates of the moving point of the particle moving in the three-dimensional space according to a given rule are calculated (step S50).

Next, perspective transformation is performed on the position coordinates of the moved particle (this is referred to as a parent particle), and the particle is arranged on the screen plane (step S60).

Next, a process of increasing the size of child particles around the parent particles after the perspective transformation is performed (step S70).

Next, sprites (one polygon) are assigned to the inflated child particles. At this time, polygon division is performed according to the distance from the generation point to the virtual camera (step S80).

Next, a packet is generated by adding a color and texture coordinates to the determined sprite polygon, and the packet is drawn (step S90).

(2) Drawing Order Determining Process First, a description will be given of a drawing order determining process performed when a splash image is generated in the present embodiment.

In general, the rendering order when performing the translucent rendering process is determined in primitive units such as polygon units in the case of a polygon object. In the present embodiment, however, the rendering order is determined for each particle generation point. are doing.

FIGS. 5A and 5B are diagrams for explaining how to determine the drawing order for each particle generation point.

FIG. 5A shows the virtual camera and the occurrence points H1 to H1.
It shows the positional relationship of H4. M1 to M4 are generation points H
FIG. 3 schematically shows splashes (particle collection objects) represented by particles generated from 1 to H4.

In this embodiment, sorting processing necessary for translucent drawing is performed for each particle generation point. For example, in the case of FIG. 5A, the order of occurrence points H1 to H4 when viewed from the virtual camera 210 is H
4, H3, H2, and H1 (see FIG. 5B). Therefore, when performing the alpha blending process on each of the splashes M1 to M4 to render the frame buffer 220 translucent, M
4, M3, M2, and M1 are drawn in the order from the depth based on the depth information of the point of occurrence in the unit of splash.

For example, the object OP3 assigned to the particle generated from the generation point H3 is drawn after the object OP4 allocated to the particle generated from the generation point H4.

As described above, in the present embodiment, a plurality of particle generation points are sorted based on their depth information, and the drawing order is determined for each generation point. Then, semi-transparent rendering processing of translucent primitives assigned to particles generated from a plurality of particle generation points is performed according to the determined rendering order.

As a result, the translucent primitive assigned to the particle generated from the point of occurrence with a higher drawing order (located at the back) is assigned to the particle generated from the point of occurrence with a lower drawing order (located at the front). The translucent drawing processing can be performed before the translucent primitive.

In this way, the processing load can be greatly reduced as compared with the case where sorting is performed for each particle and the drawing order is determined.

FIGS. 6A, 6B and 7C and FIG. 7A
FIGS. 4B and 4C are diagrams for explaining a process of determining a drawing order based on a particle generation point.

FIGS. 6A and 7A show the positional relationship between the virtual camera and the point where particles are generated before and after the movement of the virtual camera. M1 to M4 are generation points H1
7 schematically shows splashes (particle aggregate objects) represented by particles generated from H4. 210-1 is a virtual camera before moving, and 210-2 is a virtual camera after moving.

For example, in the case of FIG.
Particle generation points H1 to H1 when viewed from 10-1
The order of H4 is H4, H3, H2, H1 in order from the back.
(See FIG. 6B).

[0153] When viewed from the virtual camera 210-2, the anteroposterior relation of the translucent polygons H1 to H4 is H
3, H1, H2, and H4 (see FIG. 6C).

As described above, when the depth relationship between the generation point and the virtual camera is displaced due to the change in the positional relation between the generation point and the virtual camera, sorting processing is required.

However, for example, in the case of FIG. 7A, the order of the particle generation points H1 to H4 when viewed from the virtual camera 210'-1 is H4, H3,
H2 and H1 (see FIG. 7B), and the virtual camera 21
Particle generation point H1 when viewed from 0'-2
The order of H4 is also H4, H3, H2, H1 from the back.
(See FIG. 7C). Therefore, the virtual camera shown in FIG.
In the case where the camera moves as shown in FIG.
When drawing an image viewed from 0′-2, the sorting result performed when drawing an image viewed from the virtual camera 210′-1 can be used without performing sorting processing again.

Therefore, in the present embodiment, the necessity of a sorting process for determining the drawing order of a particle set object represented by a particle set generated from a plurality of particle generation points based on given conditions is determined, and sorting is performed. If it is determined that the processing is necessary, the sorting processing of the particle aggregation object is performed based on the depth information of the plurality of particle generation points, and the drawing order of the particle aggregation object is determined based on the processing result of the sorting processing, and the sorting processing is performed. If it is determined that is not necessary, processing for determining the rendering order of the particle aggregate object is performed based on the processing result of the previous sorting processing.

FIGS. 8A and 8B are diagrams for explaining an example in which a sorting section is set to determine the necessity of the sorting process.

In FIG. 8A, reference numeral 230 denotes a player character, and reference numeral 240 denotes a road provided in a game space which is a movement route of the player character. The player character 230 travels on a predetermined moving route 240 (a road provided in the game space), and the virtual camera is configured to follow the player character 230.

H1 to H4 are points of occurrence of splashes,
M1 to M4 schematically show the range of splashes (particle collection objects) represented by particles generated from the generation points H1 to H4.

Reference numeral 250-1 denotes a sorting section provided on the moving route. As shown in FIG. 8A, the section where the road is greatly curved is the sorting section 2
50-1. This is because when viewing the splashes M1 to M4 from the virtual camera moving in such a section, the depth relationship of the splashes with respect to the virtual camera may change as described with reference to FIGS.

As described above, in the present embodiment, an area where the position of the splash (particle collection object) where the splash occurs (the particle collection object) may change before and after the virtual camera is designated as a sorting section.

In each frame, if the position of the player character 230 is within the sorting section, it is determined that sorting processing is necessary. If the position of the player character 230 is not within the sorting section, splashing occurs. It is determined that there is no need to sort the points.

For example, the sorting section 250-1 can be designated by the distance from the start point. Further, the player character traveling on a predetermined movement route 240 (a road provided in the game space) also has a distance value from the start point as a current position. Therefore, for example, as sorting section 250-1 (2000 to 20
If 50) is set, it is determined that sorting processing is necessary if the distance value x of the current position of the player character is 2000 <x <2050.

In this way, when the player character is located outside the sorting section, the sorting processing can be omitted, so that the processing load can be reduced.

The sorting section 250-2 shown in FIG.
Is set on the movement route 240 in a section where the view is blocked by the rock object 260 and splashes are not visible. That is, while the player character is moving in the sorting section 250-2, the image captured by the virtual camera that follows the player character is included in the rock object 260.
M1 to M4 do not move.

As described above, in the present embodiment, by setting an area in which a state where no splash is displayed as a sorting section, it is possible to prevent flickering due to a change in the drawing order accompanying the sorting processing.

FIG. 9 is a flowchart for explaining an example of the flow of the drawing order determining process when performing the translucent drawing process in the present embodiment.

First, the necessity of the sorting process is determined based on whether the character object or the virtual camera is in an area where sorting is required (step S11).
0).

When the character object or the virtual camera is in an area where sorting is required, sorting processing is performed for each particle generation point based on depth information of a plurality of particle generation points, and the drawing order is determined for each particle generation point. It is determined (step S120).

If the character object or the virtual camera is not in an area where sorting is required, the drawing order is determined for each particle generation point based on the processing result of the previous sorting processing (step S13).
0).

Next, according to the determined drawing order, a semi-transparent drawing process is performed on the particle aggregate objects generated from the plurality of particle generation points (step S14).
0).

Although FIGS. 8A, 8B and 9 illustrate an example in which the sorting section is set to determine the necessity of the sorting process, the present invention is not limited to this. For example, the necessity of sorting processing may be determined based on whether the change in the arrangement of the virtual cameras is within a predetermined range.

Further, in the above-described embodiment, the case where the drawing order is determined for each generation point of the particles for expressing the splash when the splash is translucently drawn is described as an example, but the present invention is not limited to this.

For example, when performing the translucent drawing processing, the drawing order may be determined for each primitive.

FIGS. 10A, 10B and 11C and FIGS.
(A), (B), (C) is a diagram for explaining a case where the drawing order is determined for each primitive. Here, the primitive is, for example, a polygon or a sprite.

FIGS. 10A and 11A show the positional relationship between the virtual camera and the primitive before and after the movement of the virtual camera. It is assumed that P1 to P4 are, for example, translucent polygons. 210-1 is a virtual camera before moving, and 210-2 is a virtual camera after moving.

For example, in the case of FIG. 10A, the order of the translucent polygons P1 to P4 when viewed from the virtual camera 210-1 is P4, P3, P2, and P1 in order from the back (see FIG. B)).

The order of the translucent polygons P1 to P4 as viewed from the virtual camera 210-2 is P3, P1, P2, and P4 in that order (see FIG. 10C).

As described above, when the depth relationship of the translucent polygon with respect to the virtual camera is displaced due to the change in the positional relationship between the translucent polygon and the virtual camera, a sorting process is required.

However, for example, in the case of FIG. 11A, the order of the translucent polygons P1 to P4 as viewed from the virtual camera 210'-1 is P4, P3, P
2, P1 (see FIG. 11B), and the virtual camera 21
The order of P1 to P4 of the translucent polygon when viewed from 0′-2 is also P4, P3, P2, and P1 in order from the back (see FIG. 11C). Therefore, the virtual camera
In the case where the camera moves as shown in FIG.
When drawing an image viewed from 0′-2, the sorting result performed when drawing an image viewed from the virtual camera 210′-1 can be used without performing sorting processing again.

Therefore, the necessity of a sorting process for determining the drawing order of a plurality of translucent primitives is determined based on given conditions, and when it is determined that the sorting process is necessary, the plurality of translucent primitives are determined. Performs a sorting process and determines a drawing order of a plurality of translucent primitives based on a processing result of the sorting process. If it is determined that the sorting process is not necessary, a semi-transparent primitive is drawn based on a previous sorting process result. The order may be determined.

FIGS. 12A and 12B are diagrams for explaining a case where the drawing order is determined in units of objects formed as a set of primitives.

FIG. 12A shows the positional relationship between the virtual camera and the translucent objects O1 to O4. P31, P
32 is a translucent polygon belonging to the translucent object O3. P41 and P42 are translucent polygons belonging to the translucent object O4.

In such a case, in the present embodiment, sorting processing is performed for each object. For example, FIG.
In the case of (A), the order of the translucent objects O1 to O4 as viewed from the virtual camera 210-1 is O4, O3, O2, and O1 in order from the back (see FIG. 12B). Therefore, when the objects O1 to O4 are translucently rendered in the frame buffer 220 by performing the α blending process, the objects O1 to O4 are rendered in the order of O4, O3, O2, and O1 in object units from the back to the end.

That is, the polygons P31 and P32 belonging to the object O3 are drawn after the polygons P41 and P42 belonging to the object O4.

FIGS. 13 (A), (B), (C) and FIG.
(A), (B), (C) is a diagram for explaining the determination of the drawing order of the object.

FIGS. 13A and 14A show the positional relationship with the object before and after the movement of the virtual camera. O1 to O4 are assumed to be translucent objects, for example. Reference numeral 210-1 denotes a virtual camera before movement;
Reference numeral 0-2 denotes a virtual camera after the movement.

For example, in the case of FIG. 13A, the translucent objects O1 to O when viewed from the virtual camera 210-1
The order of 4 is O4, O3, O2, and O1 in order from the back (see FIG. 13B).

Further, when viewed from the virtual camera 210-2, the order of the translucent polygons O1 to O4 is as follows.
3, O1, O2, and O4 (see FIG. 13C).

As described above, when the depth relationship of the object with respect to the virtual camera is displaced due to the change in the positional relationship between the object and the virtual camera, a sorting process is required.

However, for example, in the case of FIG. 14A, the object O1 viewed from the virtual camera 210'-1 is displayed.
The order of ~ O4 is O4, O3, O2, O
1 (see FIG. 14B), and the virtual camera 210′−
14, the order of O1 to O4 of the objects when viewed from 2 is also O4, O3, O2, and O1 in order from the back (FIG. 14).
(C)). Therefore, when the virtual camera moves as shown in FIG. 14A, when drawing the image viewed from the virtual camera 210'-2, the virtual camera 210'-1 does not need to be sorted again. The result of sorting performed when rendering an image viewed from is used.

Therefore, in the present embodiment, it is determined that sorting processing is necessary for determining the drawing order of a plurality of translucent primitive sets (objects) based on given conditions, and that sorting processing is required. If it is determined, the sorting process is performed for each semi-transparent primitive set based on the representative position of the plurality of semi-transparent primitive sets (objects), and the drawing order of the plurality of semi-transparent primitive sets (objects) is determined based on the processing result of the sorting process. Is determined, and if it is determined that the sorting process is not necessary, a process of determining the drawing order of the translucent primitive set (object) based on the previous sorting process result is performed.

FIG. 15 is a flow chart for explaining another example of the flow of the drawing order determining process when performing the translucent drawing process of the present embodiment.

First, the necessity of sorting processing is determined based on whether or not the change in the arrangement of the virtual cameras is within a predetermined range (step S210). Here, the change in the arrangement of the virtual camera is, for example, a change in the position or direction (rotation) of the virtual camera.

If the change in the arrangement of the virtual cameras is within the predetermined range, the objects are sorted based on the depth information, and the drawing order is determined for each object (step S220).

If the change in the arrangement of the virtual cameras is not within the predetermined range, the drawing order is determined for each object based on the processing result of the previous sorting processing (step S230).

Next, in accordance with the determined drawing order, a semi-transparent drawing process of the primitives constituting the object is performed (step S240).

(3) Particle Inflating Process Next, a description will be given of a particle inflating process performed in generating a splash image in the present embodiment.

FIGS. 16 (A) and 16 (B) are diagrams for explaining inflating of particles.

[0200] PP1 to PP4 in Fig. 16A are particles generated in a given frame using an existing particle system. Each particle has characteristics such as color and lifetime, and is generated, moved, and annihilated by a given rule (given by the emitter) and an acting force (force).
The positions of P1 to PP4 are determined by performing calculations for determining the positions of the particles in the three-dimensional space, such as fluid calculations, collision calculations, and motion calculations, based on the emitters and forces.

Here, it is preferable to generate more particles in order to create a realistic and good-looking splash. However, in order to generate particles using an existing particle system, the above calculation is required for each particle. Therefore, as the number of generated particles increases, the amount of calculation increases accordingly.

Therefore, in the present embodiment, as shown in FIG. 16B, particles PP given in a three-dimensional space
The child particles CP11 to CP44 are generated at inflated points generated on the screen plane based on the position coordinates of the parent particles PP1 to PP4, which are perspectively transformed to the screen plane, using 1 to PP4 as parent particles.

The child particles CP11 to CP14 are generated by inflating the parent particles PP1.
The child particles CP21 to CP24 are the parent particles P
The child particles CP31 to CP34 are inflated and generated from P2, and are generated by inflating from the parent particle PP3, and are generated by inflating the child particles CP41 to CP34.
CP44 is generated by inflating parent particle PP4.

In this way, it is possible to omit the operation processing for determining the position of the child particles in the three-dimensional space using the existing particle system, so that a splash image with a volume can be generated with a small number of operations. Will be able to

FIGS. 17A and 17B are diagrams for explaining an example of determining the position and size of a child particle.

The PP1 (X1, Y1) in FIG.
This is the position coordinates of a particle (this is referred to as a parent particle) that has been perspectively transformed into the screen plane 310 at the frame.

In this embodiment, the coordinates of the padding point to be generated on the screen plane are calculated based on the position coordinates of the parent particle PP1 which has been perspective-transformed to the screen plane, and child particles are generated at the padding point.

Here, the coordinates of the first padding point M11 are represented by (x
11, y11), the coordinates of M12 of the second padding point are (x
12, y12), x11, y11, x12, y
12 is obtained as follows.

X11 = X1 + f (S, t, random number 1) (1) y11 = Y1 + f (S, t, random number 1) (2) x12 = X2 + f (S, t, random number 2) (3) y12 = Y2 + f (S, t, random number 2) (4) The coordinates (x11, y11) of the first padding point M11 and the coordinates (x
12, y12) is the generation position of the child particles CP11 and CP12. That is, (x11, y11), (x1
(2, y12) are the position coordinates of the child particles CP11 and CP12.

Here, S is a value representing a magnification or the like given in relation to the depth value z, and t is a frame number. From parent particle PP1 to child particle CP1
1, if the distance to CP12 is, for example, l1, l2,
The distance l away from the parent particle according to the depth value or the frame number is obtained by using (1) to (4).
The child particles CP11 and CP12 can be generated at 1 and 12.

The random numbers 1 and 2 indicate the positions of the random numbers to be used in the random number sequence. In a plurality of consecutive frames, the random numbers 1 and 2 are always assigned to the first child particle.
By always using the random number 2 for the child particle, the trajectory of the child particle can be made continuous in a plurality of continuous frames.

FIG. 17B is a diagram for explaining an example of the generation of a child particle when the depth value of the parent particle is z = 100 during the perspective transformation.

Here, CP'11 (x11 ', y1
1 ′), CP′12 (x′12, y′12) is generated on the screen plane 310 based on the position coordinates PP1 (X1, Y1) of the parent particle when the depth value of the parent particle is z = 100. Child particle CP'1
1. It is assumed that the position coordinates are CP'12. At this time, as shown in FIG. 17B, the child particle is generated at a position closer to the parent particle than in the case of FIG. 17A.

That is, assuming that the distances from the parent particle PP1 to the child particles CP'11 and CP'12 are, for example, l'1 and l'2, l'1 <l1, l'2 <l2
Becomes

As described above, in the present embodiment, when the depth value (z value) of the parent particle is large (when the parent particle is at a position away from the virtual camera), the child particle is generated at a close position, and the parent particle is generated. When the depth value (z-value) of is small (when the parent particle is close to the virtual camera), a child particle is generated at a position distant from the virtual camera. Therefore, the depth value (z
Value), a child particle can be generated at a position having a natural perspective relationship.

In the present embodiment, as the frame number increases (as the time after the generation of particles increases), child particles are generated at positions farther from the parent particles. By doing so, it is possible to express a state in which the spray spreads over time.

FIGS. 18A and 18B are diagrams for explaining an example in which a particle object is assigned to a generated child particle.

FIG. 18A shows a state where a sprite 350 is assigned as a particle object to a child particle CP. Sprite has two vertices SV1, S
Since it can be generated by giving V2, the positions of the two vertices SV1 and SV2 around the child particle CP are determined based on the size of the sprite 350 determined according to the depth value of the parent particle.

Here, assuming that the moving distance from the child particle CP to the two vertices SV1 and SV2 of the sprite is r1, it is given by the following equation.

R1 = local particle size × S Here, the local particle size represents the size of a particle object allocated to particles in the local coordinate system. By calculating the moving distance r1 in this manner, the size of the sprite assigned to the child particle can be reduced as the depth value (z value) of the parent particle increases (as the parent particle moves away from the virtual camera). . Therefore, a sprite having a size having a natural perspective relationship can be assigned to a child particle according to the depth value (z value) of the parent particle.

When the sprite 350 is given as a particle object to the child particle CP, the position of the child particle CP is set to one vertex SV1 of the sprite 350, and another vertex S
The position of V2 may be determined. By doing so, the calculation for determining the position of the vertex SV1 of 1 of the sprite 350 can be omitted, so that the processing load can be reduced.

FIG. 18 (B) shows a polygon object 36 as a particle object for a child particle CP.
It represents a state where 0 is assigned. Since the polygon object 360 can be generated by giving eight vertices of PV1 to PV8, the eight vertices PV1 to PV8 around the child particle CP are determined based on the size of the polygon object determined according to the depth value of the parent particle.
Determine the position of V8.

Here, assuming that the moving distance from the child particle to the eight vertices PV1 to PV8 of the polygon object is r2, it is given by the following equation.

R2 = local particle size × S Here, the local particle size represents the size of a particle object allocated to particles in a local coordinate system. By determining the moving distance r2 in this manner, it is possible to reduce the size of the polygon object allocated to the child particle as the depth value (z value) of the parent particle increases (as the parent particle moves away from the virtual camera). it can. Therefore, the depth value (z
Value), a polygon object having a size having a natural perspective relationship can be assigned to child particles.

FIGS. 19A and 19B are diagrams for explaining temporal continuity of particles. FIG.
(A) schematically shows a state of a parent particle and a child particle at t = 1 to t = 6. Here, t is a parameter indicating the passage of time, for example, a frame number or the like.

Here, at t = 1, 2,..., The positions of the parent particles of the screen planes 310-1, 310-1,... Are PPt1, PPt2, and the positions of the first child particles are CP1t1, CP1t2,. The positions of the child particles are denoted by CP2t1, CP2t2,.

As shown in the figure, in the present embodiment, the child particles generated at the (n + 1) th frame for a given parent particle are the given child particles generated at the nth frame for the same parent particle. Is generated at a position having continuity.

In this embodiment, for example, the position of the first child particle at t = 1, 2,... Is determined by using the first trajectory function 370 (see FIG. 19B) consisting of h = f1 (t). The position of the second child particle at t = 1, 2,... Is represented by a second trajectory function 38 consisting of h = f2 (t).
0 (see FIG. 19B). By doing so, it is possible to cause the first child particle and the second child particle to draw a continuous trajectory in the preceding and succeeding frames.

FIG. 20 is a flowchart for explaining the flow of the particle inflating process.

First, particles of the frame are generated in a three-dimensional space using a given particle system (step S310). Each particle has properties such as color and lifetime given by a given particle system, and determines its position in three-dimensional space based on given rules (given by the emitter) and acting forces (forces). It is generated by performing an operation.

Next, the particles in the three-dimensional space are perspective-transformed to the screen plane (step S320).

Next, the coordinates of the padding point are calculated based on the position of the parent particle, using the particle on the screen plane as the parent particle (step S330). For example, the position coordinates of the padding point may be calculated by the method described with reference to FIGS.

Next, child particles are generated at the padding point (step S340). Here, the child particles inherit the characteristic information such as the color and the lifetime of the parent particles.

Next, a particle object is assigned to the child particle (step S350). FIG.
As described in (A) and (B), sprites and polygon objects can be assigned as particle objects. For example, it is possible to generate a realistic splash image by using a sprite polygon having a translucent texture.

In the above embodiment, the case where a sprite or a polygon object is assigned to a child particle as a particle object has been described as an example. However, the present invention is not limited to this. For example, a control point of a free-form surface or another primitive may be assigned.

(4) Processing for Reducing Processing Load FIG. 21 is a flowchart for explaining an example of processing for reducing the processing load in the present embodiment.

First, the processing load during image generation is monitored, and processing load information is obtained (step 410). Here, the processing load information is given by, for example, a drawing rate per frame given by a refresh rate, a global clock, a CPU clock, or the like.

If the processing load is high, parameters for controlling at least one of the number of particle generation points, the number of particles, and the life of the particles are adjusted (steps S420 and S430). Whether the processing load is high or not is determined based on the processing load information.

Next, an example in which the number of particle generation points is controlled in consideration of depth information will be described.

FIGS. 22A and 22B are image examples when the processing load is low and when the processing load is high. In this embodiment, when the processing load is low, a large number of splashes generated on a rock or the like are generated (see FIG. 22A). However, if it is determined from the processing load information that the processing load is high, distant splashes are excluded from image generation targets. That is, the processing load is reduced by not generating the image of the splash marked with a cross in FIG. 22B or adjusting the value of the parameter. Whether it is far or not is determined based on the depth information of the splash generation point. In this manner, for the splashes marked with a cross, a series of image generation processes from particle generation processing to drawing processing required for image generation can be omitted altogether, so that the processing load can be reduced.

FIG. 23 is a flowchart for explaining an example of controlling the number of particle generation points in consideration of depth information.

First, the processing load at the time of image generation is monitored, and processing load information is obtained (step S510). Here, the processing load information is given by, for example, a drawing rate per frame given by a refresh rate, a global clock, a CPU clock, or the like.

When the processing load is high, the depth information of the particle generation point is acquired, and the particle set expressed by the particle set generated from the particle generation point distant from the virtual camera is obtained based on the depth information of the particle generation point. Objects are prioritized for image generation. (Steps S520, 530,
540).

Next, an example in which the number of particles generated from a particle generation point is adjusted in consideration of depth information will be described.

FIGS. 24A and 24B are schematic diagrams for explaining the number of particles when the processing load is low and when the processing load is high. In FIG. 24A, reference numeral 410 denotes a particle aggregate object expressing a splash, and 412 denotes a particle object constituting the particle aggregate object.

In this embodiment, when the processing load is low, a large number of particles are generated from the particle generation point, and as a result, images of a large number of particle objects are generated (see FIG. 24A).

However, if it is determined from the processing load information that the processing load is high, the number of particles generated from distant particle generation points is reduced.

[0248] Reference numeral 410 'in Fig. 24B denotes a particle set object that expresses splashes represented by particles generated from a distant generation point when the processing load is high. Whether it is far or not is determined based on the depth information of the splash generation point. Since the number of particles to be generated is smaller in the case of 410 ′ than in the case of 410, an image of a particle object that is smaller than in the case of 410 is generated (see FIG. 24B).

FIG. 25 is a flowchart for explaining an example of controlling the number of particles generated from a particle generation point in consideration of depth information.

First, the processing load at the time of image generation is monitored, and processing load information is obtained (step 610). Here, the processing load information is given by, for example, a drawing rate per frame given by a refresh rate, a global clock, a CPU clock, or the like.

If the processing load is high, the depth information of the particle generation point is obtained, and the number of particles generated preferentially from the particle generation point far from the virtual camera is reduced based on the depth information of the particle generation point. (Steps S620, 630,
640). The process of reducing the number of particles is, for example, a process of changing a parameter value for controlling the number of generated particles.

FIG. 26 is a flowchart for explaining the flow of processing in the case of adjusting particles generated from a particle generation point in consideration of depth information.

First, the processing load at the time of image generation is monitored, and processing load information is obtained (step 710). Here, the processing load information is given by, for example, a drawing rate per frame given by a refresh rate, a global clock, a CPU clock, or the like.

If the processing load is high, the depth information of the particles is obtained, and the process of shortening the life is performed with priority on the particles far from the virtual camera based on the depth information of the particles (step S720).
730, 740). For example, the sorting of the particles may be performed based on the depth information, and the life of the particles may be set to be shorter by a predetermined number from a far side.

Next, a case where the drawing processing of particles is omitted based on the transparency and the height of the particles given to the particles will be described.

FIG. 27A is a diagram schematically showing a state in which the drawing processing of the particles is omitted when the transparency given to the particles becomes a predetermined value or less.
FIG. 3B is a diagram schematically illustrating a state in which the particle drawing processing is omitted when the height of the particles becomes equal to or less than a certain value.

Pt1, Pt2, and Pt3 in FIG. 27A are diagrams showing a temporal change of particles generated from a given particle generation point. Here, the particles have transparency information (α value) as characteristic information, and the transparency information (α value) is controlled so as to decrease with time. For example, in Pt1, α = 128, and Pt2
Α is 52 in Pt3, and α = 0 in Pt3.

The transparency information (α value) is used when a particle or a particle object assigned to the particle is subjected to α blending processing or the like to perform translucent drawing. Here, for example, when the α value is 0, even if the particles or the particle objects assigned to the particles are rendered translucent, they are not displayed as transparent.

Therefore, in the present embodiment, when the transparency information (α value) given as the particle characteristic information becomes 0 or less, the particle is excluded from the object of image generation, and the subsequent particle The image generation processing is omitted.

In the above embodiment, when the transparency information (α value) given as the characteristic information of a particle becomes 0 or less, the particle is excluded from the object of image generation, and the subsequent image generation for the particle is performed. The case where the processing is omitted has been described as an example, but the present invention is not limited to this. For example, when the transparency information (α value) given as the characteristic information of the particle has reached a predetermined value, the particle may be excluded from the target of image generation, and the subsequent image generation processing on the particle may be omitted. .

P't1, P't2, and P 'in FIG.
t3 is a diagram showing a temporal change in height of particles generated from a given particle generation point. 510
Is the height of the reference plane. Here, the reference plane is, for example, a water surface or the ground. In the present embodiment, when the height of the generated particle is equal to or less than the height of the reference surface, the height of the sea surface is set as the height of the reference surface, the particle is excluded from the image generation target, and The image generation process for the particle is omitted.

FIG. 28 is a flow chart for explaining a processing flow when the particle drawing processing is omitted based on the transparency given to the particles and the height of the particles.

Steps S810 to S860 are processes performed for each frame from the occurrence of a given particle until the given particle disappears. The process of ending the particles in S870 is a process performed when the particle disappears.

First, the transparency of the particles in the frame is calculated (step 810).

Next, when the transparency of the particle is 0 or less, a particle ending process for eliminating the particle is performed (steps S820 and S87).
0).

If the transparency of the particles is not less than 0, the movement of the particles is calculated to obtain the particle position in the frame (step S82).
0, S830). In the particle movement calculation, for example, the position of the particle in each frame is determined by performing a calculation for determining the position of the particle in the three-dimensional space, such as fluid calculation, collision calculation, and motion calculation, based on the emitter and the force.

When the value regarding the height of the obtained position has reached a predetermined value, a particle ending process for extinguishing the particle is performed (step S84).
0, S870).

If the value regarding the height of the obtained position is not the predetermined value, a drawing process using particles is performed (steps S840 and S850).

If the processing of the next frame is to be performed, the processing of steps S810 to S860 is repeated again (step S860).

(5) Processing Reduction of FOG Effect When an FOG effect is to be produced, for example, in a case where an object such as a splash is realistically expressed in a manner in which the object merges into the background in accordance with the distance from the virtual camera, the depth is reduced. Perform queuing processing. For example, when depth queuing is performed on a polygon object, for each vertex, the vertex color and the background color are synthesized according to the depth value of the vertex, and the vertex color is changed according to the depth value. .

In the present embodiment, a particle object is assigned to a large number of particles that generate splashes from one particle generation point, and a set of these particle objects (particle set object)
Generate as

Therefore, in order to produce the FOG effect against the splash, the depth queuing process is required for each vertex of each particle object constituting the particle set object, so that the processing load is significantly increased.

Therefore, in the present embodiment, the following processing is performed in order to produce the FOG effect with a small processing load.

FIG. 29 is a diagram for explaining the reduction in the processing of the FOG effect.

[0275] Reference numeral 610 denotes a first particle set object for expressing splashes, and a particle object is assigned to particles generated from the first particle generation point, and is configured as a set of these particle objects. Where 612 and 61
4 is the first belonging to the first particle set object
And second particles.

[0276] Reference numeral 620 denotes a second particle set object for expressing splashes. The particle object is assigned to particles generated from the second particle generation point, and is configured as a set of these particle objects. Here, 622 and 624 are third and fourth particles belonging to the second particle aggregate object.

Here, in the present embodiment, a reference color for expressing a splash is set for the first particle set object and the second particle set object.
This reference color may be the same color for the first particle aggregate object and the second particle aggregate object, or may be different colors.

A depth skew process is performed based on the reference color and the depth value of the particle generation point of each particle aggregate object, and the color obtained by the depth skew process is used as the base color of the particle aggregate object, and the same particle An image generation process is performed on each particle belonging to a particle set generated from the generation point by applying a depth skew effect using the base color.

That is, the first particle 612 and the second particle 612 belonging to the first particle
For the particles 614, image generation processing is performed by applying a depth skew effect using the base color of the first particle aggregate object 610.

The depth skewing effect is applied to the third particles 622 and the fourth particles 624 belonging to the second particle aggregate object 610 by using the base color of the second particle aggregate object 620. Perform image generation processing.

Therefore, it is possible to greatly reduce the processing as compared with the case where the depth skewing processing is individually performed on each of the particles constituting the first particle collection object and the second particle collection object.

It should be noted that here, 61
2, 614, 622, and 624 have been described as particles, but may be vertices of the particle object assigned to the particles.

FIGS. 30A, 30B, and 30C are diagrams for explaining the depth squeezing process performed in this embodiment.

FIG. 30A is a diagram for explaining the depth skewing process for R (red). The vertical axis is R
(Red), and the horizontal axis represents the depth value (Z) of the particle generation point. Reference numeral 630 denotes the R value of the reference color set for the particle aggregate object, and 640 denotes the R value of the background color. Reference numeral 635 is a function curve for obtaining the value of R of the base color based on the depth value.

For example, when the depth value of the particle generation point is Z1, the value of the base color R is R1. When the depth value of the particle generation point is Z2, the value of the base color R is R2. .

FIG. 30B is a diagram for explaining the depth skewing process for G (green). The vertical axis is G
(Green), and the horizontal axis is the depth value (Z) of the particle generation point. Also, 650 is the value of R of the reference color set for the particle aggregate object, and 660 is the value of G of the background color. Reference numeral 655 denotes a function curve for calculating the value of the base color G based on the depth value.

For example, when the depth value of the particle generation point is Z1, the base color G value is G1. When the particle generation point is Z2, the base color G value is G2. .

FIG. 30C is a diagram for explaining the depth skewing process for B (blue). The vertical axis is B
(Blue) and the horizontal axis is the depth value (Z) of the particle generation point. 670 is the B value of the reference color set for the particle aggregate object, and 680 is the B value of the background color. Reference numeral 675 denotes a function curve for obtaining the value of B of the base color based on the depth value.

For example, when the depth value of the particle generation point is Z1, the value is B1 of the base color B, and when the depth value of the particle generation point is Z2, the value is B2 of the base color B value. .

(6) Prevention of Paging Occurrence by Polygon Division For example, when an image is generated using hardware having a limited memory resource, the capacity of a real storage area of a VRAM (frame buffer) is also limited. Therefore, when trying to draw a large polygon in a VRAM (frame buffer), paging occurs and the processing time increases.

Therefore, in the present embodiment, when the depth information of the particle object or the distance from the virtual camera increases, the number of polygons constituting the object allocated to the particle is increased to prevent the occurrence of such paging. ing.

FIG. 31 is a flowchart for explaining an example of polygon division according to the present embodiment.

First, depth information of a particle to be processed is obtained (step S910).

Next, it is determined whether or not to change the number of divisions based on the depth value, and if so, processing for dividing the polygons and sprites constituting the particle object is performed (steps S920 and S930).

FIG. 32 is a diagram showing a state in which sprites (plate polygons) constituting a particle object are divided. 710 is a sprite (plate polygon) before division
And 720 is a sprite (plate polygon) after division.

Whether or not to change the number of divisions may be determined, for example, depending on whether or not the depth information has reached a predetermined value. For example, a sorting process of particles is performed based on the depth information, and the number of particles belonging to the predetermined number from the near side is determined. The determination may be made depending on whether the polygon or sprite belongs to the assigned object.

[0297] 3. 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 is 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 process such as a matrix operation is required for a physical simulation for moving or moving an object (motion), a program operating on the main processor 900 instructs the coprocessor 902 to perform the process (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 performing high-speed parallel operations, and performs a matrix operation (vector operation). 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. Thus, a moving image compressed by a given image compression method 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 95.
0, stored in the CD 982, or transferred from the outside via the 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. The drawing processor 910 can also perform α blending (translucent processing), depth queuing, mip mapping, fog processing, trilinear filtering, anti-aliasing, shading processing, and the like. Then, when an image for one frame is written to the frame buffer 922, the image is displayed on the display 912.

[0303] The sound processor 930 incorporates a multi-channel ADPCM sound source and the like, and generates high-quality game sounds such as BGM, sound effects, and sounds. The generated game sound is output from the speaker 932.

[0304] Operation data from the game controller 942, save data and personal data from the memory card 944 are transferred via the serial interface 940.

The ROM 950 stores a system program and the like. In the case of an 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.

[0307] The DMA controller 970 provides a DM between the processor and the memory (RAM, VRAM, ROM, etc.).
A transfer is controlled.

[0308] The CD drive 980 stores CD982 in which programs, image data, sound data, and the like are stored.
(Information storage medium) to enable access to these programs and data.

[0309] 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 with another game system becomes possible.

[0310] Each means of the present invention may be entirely executed by hardware alone, 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, a program for executing each means of the present invention using hardware is stored in the information storage medium. Will be. More specifically, the program instructs the processors 902, 904, 906, 910, 930, etc., which are hardware, to perform processing, and passes data if necessary. Then, each processor 902, 904, 906, 910,
930 etc., based on the instruction and the passed data,
Each means of the present invention will be executed.

FIG. 34A 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. Information (program or data) for executing each unit of the present invention is stored in a memory 1108 which is an information storage medium on the system board 1106. Hereinafter, this information is referred to as storage information.

FIG. 34B 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 stored 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. 34C 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,
The information is stored in an information storage medium 1306 such as a magnetic tape device and a memory. When the terminals 1304-1 to 1304-n are capable of generating a game image and a game sound in a stand-alone manner, the game image,
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 terminal
1304-n and output at the terminal.

In the case of the configuration shown in FIG. 34 (C), each means of the present invention may be executed in a distributed manner 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, the portable information storage device is 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 the embodiment described above, 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 can be made dependent on another independent claim.

The display objects that can be expressed by the method of the present invention are not limited to splashes. For example, fireworks, explosions, lightning, shining amoebae, and various other display objects that emit light while deforming into an irregular shape. Can be expressed.

[0320] The method of controlling particles is not limited to the method described in the present embodiment.

In the present embodiment, the case where the object is composed of polygons has been mainly described. However, the case where the object is composed of other types of primitive surfaces such as a free-form surface is also included in the scope of the present invention. .

The present invention also relates to various games (fighting games,
Shooting games, robot fighting games, sports games, competition games, role playing games, music playing games, dance games, etc.).

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

[Brief description of the drawings]

FIG. 1 shows an example of a block diagram of an image generation system (game system) of the present embodiment.

FIG. 2 shows an example of a game image generated by the image generation device of the present embodiment.

FIG. 3 is a flowchart for explaining an overall processing flow when an image of a splash is generated by the image generation device of the present embodiment;

FIG. 4 is a flowchart illustrating an overall processing flow when an image of a splash is generated by the image generating apparatus according to the present embodiment;

FIGS. 5A and 5B are diagrams for explaining how to determine a drawing order for each particle generation point; FIG.

FIGS. 6A, 6B, and 6C are diagrams for explaining a drawing order determination process based on a particle generation point;

FIGS. 7A, 7B, and 7C are diagrams for describing a drawing order determination process based on a particle generation point;

FIGS. 8A and 8B are diagrams for explaining an example in which a sorting section is set to determine the necessity of a sorting process.

FIG. 9 is a flowchart for explaining an example of a flow of a drawing order determination process when performing a translucent drawing process in the present embodiment.

FIGS. 10A, 10B, and 10C are diagrams for explaining a case in which a rendering order is determined for each primitive;

FIGS. 11A, 11B, and 11C are diagrams for explaining a case in which a rendering order is determined for each primitive;

FIGS. 12A and 12B are diagrams for explaining a case where a drawing order is determined in units of objects configured as a set of primitives.

FIGS. 13A, 13B, and 13C are diagrams for explaining determination of an object drawing order;

FIGS. 14A, 14B, and 14C are diagrams for explaining determination of an object drawing order;

FIG. 15 is a flowchart for explaining another example of the flow of the rendering order determination process when performing the translucent rendering process of the present embodiment.

FIGS. 16A and 16B are diagrams for explaining padding of particles; FIGS.

FIGS. 17A and 17B are diagrams for explaining an example of determining the position and size of a child particle.

FIGS. 18A and 18B are diagrams illustrating an example in which a particle object is assigned to a generated child particle.

FIGS. 19A and 19B are diagrams for explaining temporal continuity of particles; FIGS.

FIG. 20 is a flowchart illustrating the flow of a particle inflating process;

FIG. 21 is a flowchart illustrating an example of a process for reducing a processing load according to the present embodiment;

FIGS. 22A and 22B are image examples when the processing load is low and when the processing load is high.

FIG. 23 is a flowchart for explaining an example of controlling the number of particle generation points in consideration of depth information.

FIGS. 24A and 24B are schematic diagrams illustrating the number of particles when the processing load is low and when the processing load is high.

FIG. 25 is a flowchart for explaining an example of controlling the number of particles generated from a particle generation point in consideration of depth information.

FIG. 26 is a flowchart for explaining the flow of processing when adjusting particles generated from a particle generation point in consideration of depth information.

FIG. 27A is a diagram schematically illustrating a state in which the drawing processing of the particle is omitted when the transparency given to the particle becomes equal to or less than a predetermined value.
FIG. 3B is a diagram schematically illustrating a state in which the particle drawing processing is omitted when the height of the particles becomes equal to or less than a certain value.

FIG. 28 is a flowchart for explaining a processing flow in a case where particle rendering processing is omitted based on the transparency or particle height given to the particles.

FIG. 29 is a diagram for describing processing reduction of the FOG effect.

FIGS. 30A, 30B, and 30C are diagrams for describing depth skewing processing performed in the present embodiment.

FIG. 31 is a flowchart illustrating an example of polygon division according to the present embodiment.

FIG. 32 is a diagram illustrating a state in which sprites (plate polygons) constituting a particle object are divided.

FIG. 33 is a diagram illustrating an example of a hardware configuration capable of realizing the present embodiment.

FIGS. 34A, 34B, and 34C are diagrams illustrating examples of various types of systems to which the present embodiment is applied.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 processing unit 110 game processing unit 120 image generation unit 130 drawing order determination processing unit 132 particle padding processing unit 134 particle load reduction processing unit 140 drawing unit 150 sound generation unit 160 operation unit 170 storage unit 172 main memory 174 frame buffer 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 F term (reference) 2C001 BC00 BC05 BC06 BC10 CB01 CC02 CC03 CC08 5B050 BA08 BA09 BA11 EA12 EA13 EA23 EA27 EA28 EA29 5B080 BA01 DA06 FA06 FA09 GA01 GA18

Claims (33)

[Claims] 1. A system for generating an image, comprising: means for changing at least one of the number of particle generation points, the number of particles, and the life of the particles based on information on a processing load at the time of image generation; Means for generating an image viewable from a given viewpoint in object space; 2. The image generation system according to claim 1, wherein the number of particles is the number of particles existing on one screen or the number of particles generated from a given generation point. 3. The image generation method according to claim 1, wherein the processing load is reduced by shortening the life of the particles farther from the virtual camera based on the depth information of the particles. system. 4. The method according to claim 1, wherein a particle set generated from a particle generation point remote from the virtual camera is preferentially excluded from image generation based on depth information of the particle generation point. And an image generation system for reducing a processing load. 5. The processing load according to claim 1, wherein the number of particles to be preferentially generated from a particle generation point far from the virtual camera is reduced based on depth information of the particle generation point. An image generation system characterized in that the image is reduced. 6. The method according to claim 1, wherein the processing load is reduced by lowering the precision of the object preferentially to an object assigned to a particle distant from the virtual camera based on the depth information of the particle. Characteristic image generation system. 7. The object according to claim 1, wherein the precision of the object is reduced by giving priority to an object assigned to a particle generated from a particle generation point distant from the virtual camera based on depth information of the particle generation point. And an image generation system for reducing a processing load. 8. A system for generating an image, wherein when the degree of transparency given to a particle or an object assigned to a particle becomes smaller than a predetermined value, the object of the image generation is set to the particle or the object assigned to the particle. An image generation system, comprising: means for excluding from an object; and means for generating an image viewed from a given viewpoint in an object space using particles. 9. A system for generating an image, comprising: means for performing a process of extinguishing a particle or an object assigned to the particle when the height of the particle reaches a predetermined value; Means for generating an image visible from a viewpoint. 10. The image generation system according to claim 9, wherein the extinction processing includes a case where the particles or the objects assigned to the particles disappear after a predetermined time has elapsed. 11. A system for generating an image, wherein it is determined whether or not there is an object that blocks the field of view based on depth information of the particle, and if there is an object that blocks the field of view, the object is assigned to the particle or the particle. An image generation system, comprising: a unit for excluding an object from a target of image generation; and a unit for generating an image viewed from a given viewpoint in an object space using particles. 12. A system for generating an image, comprising: a depth based on depth information of a particle generation point with respect to a reference color set for a particle collection object expressed by a particle set generated from the same particle generation point. Means for performing cueing processing, using the color obtained by the depth cueing processing as a base color of a particle set object, and using the base color for each particle belonging to a particle set generated from the same particle generation point. Means for performing an image generation process by applying a depth cueing effect. 13. A system for generating an image, wherein a particle object is formed based on at least one of depth information of the particle object, a positional relationship with respect to a virtual camera, and a ratio of a drawing area of a primitive constituting the particle object to a screen. An image generation system, comprising: means for controlling the number of divisions of a primitive; and means for generating an image viewed from a given viewpoint in an object space using particles. 14. The image generation system according to claim 13, wherein when the depth information of the particle object or the distance from the virtual camera increases, the number of divisions of primitives constituting the particle object is increased. 15. The image generation system according to claim 13, wherein the number of divisions of the primitives constituting the particles is increased when the ratio of the drawing area of the primitives constituting the particle object to the screen increases. . 16. The image generation system according to claim 13, wherein the number of divisions is increased by subdividing a primitive assigned to a particle. 17. A computer-usable program, comprising: means for changing at least one of the number of particle generation points, the number of particles, and the life of particles based on information on a processing load at the time of image generation; Means for generating an image which can be viewed from a given viewpoint in an object space by using a computer. 18. The program according to claim 17, wherein the number of particles is the number of particles existing on one screen or the number of particles generated from a given generation point. 19. The program according to claim 17, wherein the processing load is reduced by shortening the life of the particles preferentially from the particles far from the virtual camera based on the depth information of the particles. 20. The method according to claim 17, wherein a particle set generated from a particle generation point distant from the virtual camera is preferentially excluded from image generation based on depth information of the particle generation point. And a program for reducing the processing load. 21. The processing load according to claim 17, wherein the number of particles generated preferentially from a particle generation point far from the virtual camera is reduced based on depth information of the particle generation point. A program characterized by reduction. 22. The method according to claim 17, wherein the processing load is reduced by lowering the precision of the object by giving priority to an object assigned to a particle distant from the virtual camera based on the depth information of the particle. Features program. 23. The method according to claim 17, wherein the precision of the object is reduced by giving priority to an object assigned to a particle generated from a particle generation point distant from the virtual camera based on depth information of the particle generation point. And a program for reducing the processing load. 24. A computer-usable program, wherein when the transparency given to a particle or an object assigned to a particle becomes smaller than a predetermined value, the particle or the object assigned to the particle is used for image generation. A program for causing a computer to execute: means for excluding from an object; and means for generating an image viewed from a given viewpoint in an object space using particles. 25. A computer-usable program, comprising: means for erasing a particle or an object assigned to the particle when the height of the particle reaches a predetermined value; and providing a given object space using the particle. Means for generating an image that can be viewed from the viewpoint of a computer, and a program that causes a computer to realize the following. 26. The program according to claim 25, wherein the extinction processing includes a case where the particles or objects assigned to the particles disappear after a lapse of a predetermined time. 27. A computer-usable program that determines whether there is an object that blocks a view before the object based on depth information of the particle. A program for causing a computer to realize: means for excluding an assigned object from a target of image generation; and means for generating an image viewed from a given viewpoint in an object space using particles. 28. A computer-usable program, based on depth information of a particle generation point with respect to a reference color set for a particle collection object expressed by a particle collection generated from the same particle generation point. Means for performing a depth skewing process, using the color obtained by the depth skewing process as a base color of a particle set object, and using the base color for each particle belonging to a particle set generated from the same particle generation point. And a means for performing an image generation process by applying a depth skew effect to a computer. 29. A program usable by a computer, wherein a particle object is formed based on at least one of depth information of a particle object, a positional relationship with respect to a virtual camera, and a ratio of a drawing area of a primitive constituting the particle object to a screen. A program for causing a computer to realize: means for controlling the number of divided primitives to be executed; and means for generating an image viewed from a given viewpoint in an object space using particles. 30. The program according to claim 29, wherein when the depth information of the particle object or the distance from the virtual camera increases, the number of divisions of primitives constituting the particle object is increased. 31. The program according to claim 29, wherein when the ratio of a drawing area occupied by a primitive constituting a particle object to a screen increases, the number of divisions of the primitive constituting the particle is increased. 32. The program according to claim 29, wherein the number of divisions is increased by subdividing a primitive assigned to a particle. 33. An information storage medium usable by a computer, wherein the information storage medium includes the program according to any one of claims 17 to 32.