JP2001229395A - Game system and information storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a game system which can perform more real rendering expression of a plurality of objects included in a given frame with reduced processing burden and to provide an information storage medium. SOLUTION: In this game system where images are generated, a processing switching part 132 decides the type of each of the plurality of objects arranged in a three-dimensional space according to the distance between a virtual camera and the objects every time these objects are rendered. A geometry operation part 132 performs the geometry operations for executing the rendering processes with different degrees of precision according to the aforementioned types of objects. The contents of at least one of the texture mapping, reflection, shading, light source and semitransparent processes are omitted or simplified to perform the rendering process in response to this process type.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a game system 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.

In such a game system, it is an important technical problem to generate a more realistic image in order to improve the virtual reality of the player.

Here, various rendering methods such as shading processing, light source processing, environment mapping, multi-texture mapping, translucent processing, reflection processing, processing in consideration of the material and attribute of an object, the influence of a light source, the direction to a virtual camera, and the like are used. By making full use of, it is possible to generate a more realistic image.

However, since such various rendering processes generally require a large amount of calculation, when the number of objects increases,
This causes an increase in processing load.

Therefore, in a home-use or arcade game system or the like that requires real-time image generation with limited hardware resources, if the processing load increases, the image generation cannot be completed in time and an unfinished image is displayed. There is a possibility that troubles such as display failure, display omission, etc. may occur.

However, if the above-described various rendering processes are omitted uniformly in order to prevent the occurrence of a problem, the reality of the image is impaired. Therefore, it is desired to generate an image as realistic as possible within a range where such a defect does not occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to realize a more realistic rendering expression with a small processing load for a plurality of objects in a given frame. It is to provide a game system and an information storage medium.

[0009]

SUMMARY OF THE INVENTION The present invention is a game system for generating an image, wherein when generating an image of a given frame, a plurality of different types of rendering processes are performed based on given conditions. It is characterized by including means for selecting a type of rendering processing for each object, and means for performing rendering processing according to the type selected for each object to generate an image of the given frame.

[0010] An information storage medium according to the present invention is an information storage medium usable by a computer, and includes a program for executing the above means. Further, the program according to the present invention is a program usable by a computer (including a program embodied in a carrier wave), and includes a processing routine for executing the above means.

Here, the type of rendering processing is a rendering format that is divided according to the difference in rendering method to be applied, and the model information to be input is irrelevant to the type of rendering processing. Further, the rendering technique means various types of rendering techniques such as texture mapping types, light source processing, translucent processing, and reflection processing.

Depending on the type of rendering processing, the atmosphere of the generated image, the degree of reality, the calculation load, and the like differ.

According to the present invention, the type of rendering processing can be selected for each object within one frame based on given conditions. Therefore, by selecting an optimal type of rendering processing for each object according to the purpose, it is possible to efficiently generate an image that can obtain a desired rendering effect.

The present invention is a game system for generating an image, and determines a type of rendering a plurality of objects arranged in a three-dimensional space for each object based on given conditions. Means for performing rendering processing with different degrees of precision according to the type determined for each object to generate images of the plurality of objects.

Further, an information storage medium according to the present invention is an information storage medium usable by a computer, and includes a program for executing the above means. Further, the program according to the present invention is a program usable by a computer (including a program embodied in a carrier wave), and includes a processing routine for executing the above means.

Here, the type of the rendering process is a rendering format that is divided according to the difference in the rendering method to be applied, and the model information to be input is irrelevant to the type of the rendering process. Further, the rendering technique means various types of rendering techniques such as texture mapping types, light source processing, translucent processing, and reflection processing.

The atmosphere, the degree of reality, the calculation load, and the like of the generated image differ depending on the type of the rendering process.

In general, the precision refers to the degree to which the details are skillfully expressed and whether or not attention is kept to a fine point. Here, too, the rendering processing is skillfully expressed to details and the point at which attention is paid to details. I use it in the sense that it keeps going. Therefore, the rendering processing with different degrees of precision means, for example, rendering processing with different degrees of realism and detail of expression. In general, the higher the precision, the more complicated the processing. Therefore, the processing may be different in complexity.

The rendering process with low precision is, for example, a rendering process in which various types of rendering processes such as a type of texture mapping, a light source process, a translucent process, and a reflection process are omitted or simplified. The degree of precision of the rendering process may be determined according to the degree.

According to the present invention, a plurality of objects arranged in a three-dimensional space can be subjected to rendering processing with different degrees of precision for each object based on given conditions.

Therefore, by performing rendering processing with different degrees of precision for each object in accordance with the purpose, compared to a case where rendering processing of the same degree of precision is uniformly applied to a plurality of objects, a desired high image can be efficiently obtained with a small calculation load. Can be generated.

Here, it is preferable to determine the precision at the time of rendering the object based on the magnitude of the effect of the object on the realism of the entire image of the object. As a result, not all objects in one frame are rendered with the same precision, but those that have a large effect on the realism of the entire image are subjected to a high-precision rendering process. Smaller objects can be rendered with lower precision, and a more realistic image can be generated with less processing load.

The game system, the information storage medium, and the program according to the present invention include at least one of a texture mapping process, a reflection process, a shading process, a light source process, and a translucent process according to the type of the rendering process. Is omitted or simplified to perform the rendering process.

Here, the light source processing includes shading processing based on the positional relationship with the light source, processing for expressing light reflection, and the like. The reflection processing is processing for expressing reflection based on the positional relationship between the virtual camera and the primitive. The translucent process is a process of performing translucent drawing on a transparent part of an object by an alpha mapping process or the like.

The texture mapping processing includes environment mapping, multi-texture mapping, and the like. To omit or simplify the texture mapping processing includes, for example, omitting the environment mapping processing or reducing the number of times of multi-texture mapping. Includes the case.

According to the present invention, at least one of texture mapping processing, reflection processing, shading processing, light source processing, and translucent processing is performed according to the type of rendering processing.
By performing the rendering process by omitting or simplifying the contents of the two processes, the precision of the rendering process can be changed or the processing load can be changed depending on the type.

A game system, an information storage medium, and a program according to the present invention perform a geometry operation using attribute data given to a definition point of the object to generate attribute data of a definition point required at the time of drawing. Computing means, and a drawing means for drawing an object based on the attribute data of the definition points required at the time of drawing, wherein the geometry calculation means includes, among the attribute data of the definition points required at the time of drawing, other than the definition point coordinates. And a geometric operation is performed by simplifying the process of generating attribute data according to the type of the rendering process.

Here, the definition point of the object is
This is a point for defining (specifying) the shape of an object, and includes vertices of a polygon, control points of a free-form surface, and the like.

The attribute data is property data associated with graphic primitives such as points, lines, and surfaces, and has an effect on rendering characteristics. For example, attribute data of a definition point (vertex, control point) of an object includes color (luminance),
There are position, texture coordinates, normal vector, α value, and depth queuing background color.

According to the present invention, among the attribute data of the definition points required at the time of drawing, the process of generating the attribute data other than the definition point coordinates is simplified according to the type of the rendering process, and the geometry calculation is performed. The operation load of the geometry operation can be reduced according to the type of the rendering processing.

Further, in the game system, the information storage medium and the program according to the present invention, the geometry calculation means may include:
Of the attribute data of the definition point required at the time of drawing,
It has a plurality of processing routines with different algorithms for generating attribute data other than the definition point coordinates, and performs a calculation by selecting a given routine according to the type of the rendering processing. .

In the present invention, since the geometry calculation is executed by a program, a plurality of processing routines of an algorithm having different numbers of processing steps and data accesses are used.
By selecting a processing routine according to the type, the calculation load of the geometry calculation can be reduced.

The game system, the information storage medium, and the program according to the present invention perform a geometry calculation based on attribute data given to a definition point of an object and generate attribute data of a definition point required at the time of drawing. Means, and a drawing processor for performing a drawing process based on attribute data of a defined point required at the time of drawing, wherein the geometry calculation means includes a color, a luminance, an α value given to a defined point of an object in a three-dimensional space. For the process of generating attribute data of a defined point required at the time of drawing using at least one attribute data of mapping information value and normal line information information, a plurality of processing routines having different execution step numbers or execution access numbers are required. According to the type of the rendering process. Te, and executes the process by switching the processing routine.

In the game system, the information storage medium, and the program according to the present invention, the given condition includes a condition relating to a distance between the object and the virtual camera.

According to the present invention, the precision of the rendering process can be changed according to the distance between the virtual camera and the object.

Here, it is preferable to perform a type of rendering processing with lower precision as the object moves away from the virtual camera.

Objects located in the foreground appear large, and if they are not realistically represented using a high-precision rendering method, the realism of the image will be reduced. Even if a low rendering process is performed, the effect on the realness of the entire image is small.

Therefore, according to the present invention, an object close to the virtual camera is subjected to highly precise rendering processing,
By performing low-precision rendering processing on an object separated from the virtual camera, it is possible to generate a more realistic image with a smaller processing load for all objects in one frame than when performing rendering processing with the same precision. I can do it.

The game system, the information storage medium, and the program according to the present invention are characterized in that the given condition includes a condition relating to a degree of influence of the light source on the object.

According to the present invention, the precision of the rendering process can be changed in accordance with the degree of the effect of the light source on the object.

For example, when the light source is a point light source, the degree of influence from the light source depends on the distance between the light source and the object. When the light source is a parallel light source, the effect from the light source depends on the direction of the object and the light source. The degree of influence differs, and the degree of influence from the light source also differs depending on the number of light sources.

Therefore, it is preferable to determine the precision at the time of rendering in consideration of the degree of these effects on the object.

As described above, according to the present invention, with respect to the object within one frame, the object having a high degree of influence from the light source is subjected to the high-precision rendering processing, and the object having a low degree of influence from the light source is subjected to the high precision. By performing a low rendering process, a more realistic image can be generated with a smaller processing load than when rendering is performed with the same precision.

Further, the game system, the information storage medium and the program according to the present invention are characterized in that the given condition includes a condition relating to an arrangement of an object, a light source and a virtual camera.

According to the present invention, the precision of the rendering process can be changed according to the arrangement of the object, the light source, and the virtual camera. Therefore, it is preferable to represent the illuminated object close to the virtual camera with high precision.

The game system, the information storage medium, and the program according to the present invention are arranged so that, when the given condition is to generate an image by generating objects of a plurality of sizes having different magnifications based on the same model, It is characterized by including a condition relating to the magnification.

According to the present invention, when generating an image by generating objects of a plurality of sizes having different magnifications based on the same model, the precision of the rendering process can be changed according to the magnification. Therefore, it is preferable to express an object having a high magnification with high precision.

Further, the game system, the information storage medium and the program according to the present invention can
An arithmetic process of generating color information or luminance information of a definition point of an object after geometry processing based on color information given as attribute information to the definition point of the object is simplified according to the type of the rendering process. It is characterized by the following.

When the texture mapping is performed, the brightness information of the definition point of the object after the geometry processing is obtained.
When the texture mapping is not performed, the color information is the definition point of the object after the geometry processing.

The arithmetic processing may be, for example, a case in which the read color information is output as it is, or a case in which a luminance value generated by performing a light source processing operation based on a normal vector or a light vector is output. These can be simplified according to the type of the rendering process.

The simplification of the arithmetic processing for generating the color information or the luminance information includes the case where the processing is omitted. For example, the color information provided as the attribute information at the definition point of the object is not read and the fixed color information is not read. Is output as color information or luminance information of the definition point of the object after the geometry processing.

Further, the game system, the information storage medium and the program according to the present invention can
The color information of the defined point after the geometry processing according to the normal vector given as attribute information to the defined point of the object and the degree of light reflection calculated based on at least one of the direction of the virtual camera and the direction of the light ray, or The arithmetic processing for generating the luminance information is performed in a simplified manner according to the type of the rendering processing.

The simplification includes the case where it is omitted.

When this is simplified, an image with low precision, which is shaded and does not reflect the direction of the line of sight or the peeling of light rays, is generated.

The game system, the information storage medium, and the program according to the present invention, when performing a geometry operation,
The arithmetic processing for generating an alpha value necessary for semi-transparently rendering an object after geometry processing based on an α value given as attribute information to a defined point of the object is simplified according to the type of the rendering processing. It is characterized by performing.

The simplification includes the case where it is omitted.

When this is simplified, a low-precision image in which a portion of the object that should be seen through is not translucent is generated.

The game system, the information storage medium, and the program according to the present invention are characterized in that the rendering process is performed by omitting the process of mapping the environment of the object according to the type of the rendering process.

Further, the game system, the information storage medium, and the program according to the present invention are characterized in that the rendering process is performed by changing the number of times texture mapping is performed on an object according to the type of the rendering process.

[0060]

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 the present embodiment. In this figure, the present embodiment only needs to include at least the processing unit 100, and the other blocks can be optional components.

The processing unit 100 performs various processes such as control of the entire system, instruction of commands to each block in the system, game processing, image processing, sound processing, and the like. Processor (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 (a 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 (particularly, the blocks included in the processing unit 100) of the present invention (the present embodiment).

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

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

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

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

The communication unit 196 performs various controls for communication 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 the information storage medium of such a host device (server) is also included in the scope of the present invention.

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

Here, the game processing section 110 performs processing for accepting coins (price), setting processing for various modes, processing for proceeding with a game, setting processing for a selection screen, position and rotation angle of an object (one or a plurality of primitive surfaces). Processing for calculating (the rotation angle around the X, Y or Z axis), processing for moving the object (motion processing), processing for obtaining the position of the viewpoint (the position of the virtual camera) and the line of sight (the rotation angle of the virtual camera), the map object Processing for arranging objects such as objects in the object space, hit check processing, processing for calculating game results (results, results), processing for playing by a plurality of players in a common game space,
Or various game processing such as game over processing,
This is performed based on operation data from the operation unit 160, personal data from the save information storage device 194, a game program, and the like.

The image generation unit 130 includes a game processing unit 110
Performs various image processing in accordance with an instruction from the camera, generates an image that can be viewed from a virtual camera (viewpoint) in the object space, and outputs the generated image to the display unit 190. In addition, the sound generation unit 150 performs various types of sound processing according to instructions from the game processing unit 110 and the like, generates sounds such as BGM, sound effects, and sounds, and outputs the sounds to the sound output unit 192.

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

The game processing section 110 includes a movement / motion calculation section 112 and a viewpoint distance calculation section 114.

Here, the movement / motion calculation unit 112 calculates movement information (position data and rotation angle data) and movement information (position data and rotation angle data of each part of the object) of an object such as a car. For example,
Based on operation data, a game program, and the like input by the player via the operation unit 160, a process of moving or moving an object is performed.

More specifically, the movement / motion calculation unit 112
Performs a process of obtaining the position and rotation angle of the object, for example, for each frame (1/60 second). For example, (k-
1) The position of the object in the frame is PMk-1, the speed is VMk-1, the acceleration is AMk-1, and the time of one frame is Δt.
And Then, the position PM of the object at the k frame
k and the speed VMk are obtained, for example, as in the following equations (1) and (2).

PMk = PMk−1 + VMk−1 × Δt (1) VMk = VMk−1 + AMk−1 × Δt (2) The viewpoint distance calculation unit 114 calculates the distance between each object and the virtual camera.

The image generation unit 130 includes the geometry processing unit 1
32, and a drawing unit 140.

Here, the geometry processing unit 132 performs various types of geometry processing (three-dimensional operation) such as coordinate transformation, clipping processing, perspective transformation, and light source calculation. Then, the object data (shape data such as vertex coordinates of the object, vertex texture coordinates, luminance data, etc.) after the geometry processing (after the perspective transformation) is stored in the storage unit 17.
0 in the main memory 172.

The geometry processing section 132 includes a processing type selection section 134. The processing type selection unit 134 determines, for each of the plurality of objects arranged in the three-dimensional space, the type of rendering the object based on the distance from the virtual camera to the object.

The geometry calculation unit 132 performs a geometry calculation for performing rendering processing with different degrees of precision depending on the type.

The drawing section 140 performs processing for drawing the object (model) after the geometry processing in the frame buffer 174.

Note that the game system of the present embodiment
The system may be a system dedicated to the single player mode in which only one player can play, or a system having 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 image and the game sound to be provided to the plurality of players may be generated using one terminal, or may be generated using a plurality of terminals connected by a network (transmission line, communication line) or the like. Is also good.

2. Features of the present embodiment Features of the present embodiment will be described below with reference to the drawings.

FIG. 2 is an image showing the state of a school of fish in water. When generating an image containing many fish objects like the fish school shown in the figure, shading processing, light source processing, environment mapping, multi-technical mapping, translucent processing, reflection processing, object material By making full use of various rendering methods such as processing considering the influence of attributes and light sources, the direction to the virtual camera, and the like, it is possible to generate a more realistic fish image.

However, since such various rendering processes generally require a large amount of calculation, if this process is performed on all fish in the school of fish shown in FIG. 2, the processing load is significantly increased, real-time image generation becomes difficult, and the process is not completed. There is a possibility that problems such as the display of an image or display omission may occur.

However, the fish located in the foreground looks large, so if it is not realistically rendered by using a high-precision type of rendering processing, the reality of the image will be reduced. Therefore, even if a low-precision type rendering process is used, the effect on the realism of the entire image is small.

The feature of the present embodiment is that the rendering process is not performed for all objects in one frame with the same precision, but for each object in accordance with the magnitude of the effect on the realism of the entire image. The point is that you can select the type. Therefore, the processing load is reduced by performing a high-precision type rendering process on an image having a large effect on the realness of the entire image and performing a low-precision type rendering process on a component having a small effect on the reality of the entire image. Can generate a more realistic image.

The features of the present embodiment will be described below by taking, as an example, a case of performing a type of rendering processing with different degrees of precision according to the distance from the virtual camera.

FIGS. 3A to 3C are diagrams for explaining the relationship between rendering processing of different types of precision and processing load. 3 (A) to 3 (C), 3
Reference numerals 20 and 330 schematically depict images obtained by performing different types of rendering processing on fish of the same model.

Reference numeral 310 in FIG. 3A denotes an image of a fish object generated by a high-precision type rendering process. Since a realistic light source, texture mapping process, and the like are performed, the processing load is increased. (Processing load: 60).

Reference numeral 320 in FIG. 3B denotes an image of a fish object generated by a rendering process of a medium precision type, which has been subjected to a light source, a texture mapping process, and the like, which are usually used, and has a processing load. Is medium (processing load: 30).

Reference numeral 330 in FIG. 3C denotes an image of a fish object generated by a low-precision type rendering process. Since the light source, the texture mapping process, and the like are simplified, the processing load is small. Load: 1
2).

As described above, the processing load ratio when the precision is high, medium, and low for the fish object of the same model is 60:30:12 in this example. The higher the type, the greater the processing load.

FIGS. 4A and 4B are diagrams for explaining the relationship between the distance of the object from the virtual camera and the precision of the rendering process.

As shown in FIG. 4A, in the present embodiment, an object subjected to low-precision type rendering processing is used for a distant view (away from the virtual camera), and a medium-precision type object is used. The object that has been subjected to the rendering processing is used for the middle view, and the object that has been subjected to the high-precision type rendering processing is used for the foreground (close to the virtual camera).

As for the specific relationship between the distant, middle, and near views and the distance from the virtual camera, it is desirable to set an optimal value for each image or game.

FIG. 4B schematically shows an image generated by performing a rendering process of a type having a different degree of precision on each fish object in one frame according to the distance from the viewpoint. 310-1 to 310-6 are subjected to a high-precision type rendering process in order to fall into the foreground, and 320-1 to 320-4 are rendered to a medium-precision type rendering process in order to fall into the middle view. , And 320-1 to 320-5 are located in a distant view, so that a low-precision type rendering process is performed.

In this manner, a rendering process of a higher precision type is applied to an image which has a greater influence on the realness of the entire image, and a rendering process of a lower precision type is applied to an image having a small effect on the reality of the entire image. Can be applied. Therefore, an effect close to the case of performing the rendering processing with the same precision can be realized with a small processing load.

FIGS. 5A and 5B are diagrams for explaining image examples that can be realized with the same processing load.

FIG. 5A is a diagram schematically showing an image generated when rendering processing of a medium precision type is performed on all fish objects. Assuming that the processing load capable of generating an image in one frame is 240, the processing load of the medium-precision type rendering processing is 30. Therefore, only eight objects can be output as shown in FIG. Becomes

FIG. 5B shows a low-precision type rendering process performed on fish objects 320-1 to 320-4 distant from the virtual camera, and a fish object 330 at a short or medium distance from the virtual camera. -1 to
FIG. 330-10 is a diagram schematically illustrating an image generated when rendering processing of a medium precision type is performed. Assuming that the processing load capable of generating an image in one frame is 240, the processing loads of the medium precision type rendering processing and the low precision type rendering processing are 30 and 12, respectively. 5
As shown in (B), 14 objects can be output.

As described above, the processing load is reduced by employing the low-precision type rendering processing when displaying an object far from the virtual camera, so that only the normal precision-type rendering processing is uniformly performed. The number of objects to be output can be increased as compared with the case of outputting with.

FIG. 5C shows a high-precision type rendering process for the fish objects 310-1 and 310-2 that are close to the virtual camera, so that the fish objects 320-1 to 320-1 at an intermediate distance from the virtual camera. 320-4
FIG. 3 is a diagram schematically illustrating an image generated when a rendering process of a medium precision is performed.
Assuming that the processing load capable of generating an image in one frame is 240, the processing loads of the high-precision type rendering processing and the medium-precision type rendering processing are 60 and 30, respectively. Although the number of objects to be output is small as shown in FIG. 5 (C), a realistic expression is possible.

When it is desired to display a close object from the virtual camera in a realistic manner, by performing a high-precision type rendering process on the close object, the number of output objects is reduced, but a more realistic expression is possible. Become.

Next, in the present embodiment, a specific method for reducing the calculation load by selecting and executing the type of rendering processing for each object will be described.

A case where rendering processing is performed on an object having given model information arranged in a three-dimensional space in the present embodiment will be described with reference to FIG.

When rendering processing 240 is performed on an object arranged in a three-dimensional space, in the present embodiment, a geometry calculation program is first executed by a CPU or a dedicated processor based on predetermined information 220 and 230 to obtain a geometry calculation program. Step 250 is performed.

Here, 220 is information relating to the position coordinates (a1) of the object and the distance (b1) between the object and the virtual camera, and is calculated by the CPU.

Reference numeral 230 denotes attribute information 230 given to each vertex of the object as model information of the object. The attribute information 230 given to each vertex includes a vertex coordinate value (b1), a vertex color value (b2), and an alpha mapping information value (b
3), including the normal vector value (b4).

Here, the vertex color value is given as, for example, an RGB value, alpha is, for example, an α value used when performing a translucency operation, and the mapping information value is a texture coordinate value such as UV or STQ.

As a result of the geometry processing, the vertex attribute information 260 converted into the screen coordinate system after the geometry processing is generated based on the attribute information 230 of each vertex of the object in the three-dimensional space.

Attribute information 2 after geometry processing
Reference numeral 60 includes a vertex coordinate / fog value (c1), a vertex color / α value (c2), and a texture coordinate value (c3). Here, the vertex coordinates are vertex coordinates in the screen coordinate system, and the fog value is a coefficient or the like obtained from depth information when performing the depth queuing process. The vertex color is information that indicates the luminance of the vertex when texture mapping is performed, and is the value that is the information that indicates the color of the vertex when texture mapping is not performed. The α value is a value necessary for performing translucent drawing or the like. The texture coordinate value is a UV value or STQ value of a texture to be mapped.

The geometry processing 250 according to the present embodiment comprises:
It has a plurality of types of processing routines for performing rendering processes with different degrees of precision.

Processing 1 (252) is a distant view processing routine, and processing 1 is executed when the object is away from the virtual camera. Process 2 (254) is a middle view process routine, and if the object is slightly away from the virtual camera, process 2 is executed. Processing 3 (254) is a near-view processing routine, and when the object is close to the virtual camera, processing 3 is executed.

The distant view processing routine, the middle view processing routine, and the distant view processing routine executed in the processing 1, the processing 2 and the processing 3 all use the vertex attribute information 230 given as model information to perform the geometry processing. This is a routine for generating the attribute data of the later vertex, but is a routine in which the number of steps at execution or the number of accesses at execution is different.

The number of steps at the time of execution or the number of times of access at the time of execution is higher in the routine for generating the attribute data of the vertices after the geometry processing for performing the rendering processing with high precision. Therefore, the number of steps or the number of accesses at the time of execution of the near view processing routine is the highest, and the number of steps at the time of execution of the distant view routine or the number of accesses at the time of execution is lowest.

In this embodiment, this processing can be selected for each object. Therefore, for example, a process with a high calculation load can be selected only for an object that requires a realistic expression such as a near view, and a process with a low calculation load can be selected for an object that does not require realism, such as a distant view.

As described above, by appropriately using each processing in accordance with, for example, the distance between the object and the virtual camera, it is possible to perform the optimum rendering processing with a small calculation load.

FIG. 7 is a diagram for explaining the type of rendering processing in each geometry processing routine.

Processing 1 is a geometry processing routine for executing a type of rendering processing for performing only environment mapping.

Processing 2 is a geometry processing routine for executing a type of rendering processing of performing environment mapping, translucent processing, and vertex color (luminance) reflection processing.

Processing 3 is a geometry processing routine for executing a type of rendering processing of performing environment mapping, translucent processing, and reflection processing.

In the present embodiment, reflection mapping expressing reflection on the object surface is performed as environment mapping. In such environment mapping, a virtual sphere or a virtual cylinder is considered in a three-dimensional space where an object exists, an environment texture is pasted on the inner surface thereof, and a display is made such that the texture is reflected on the surface of the object.
The reflection direction vector is determined by the viewpoint position (the position of the virtual camera) and the coordinates of a point on the object surface, and the texture coordinates (texture coordinate value) corresponding to the reflection direction vector
Is determined.

Therefore, when environment mapping is performed as rendering processing, processing for calculating a texture coordinate value based on the viewpoint position (the position of the virtual camera) and the vertex coordinates is required.

Since all of the processing 1, the processing 2 and the processing 3 perform the environment mapping, all the processing routines require the processing of calculating the texture coordinate value for performing the environment mapping.

The translucent process is a process for translucently expressing a transparent portion such as a fin of a fish. More specifically, this is realized by performing α blending processing when rendering rendering data in pixel units. The α value used for the α blending processing is passed to the rendering processor as attribute information of the vertices after the geometry processing. Processing is required. That is, it is necessary to set the α value set at each vertex as model information in the attribute information of the vertex after the geometry processing.

Since both processes 2 and 3 perform translucent processing, these processing routines need to set the α value set at each vertex as model information in the attribute information of the vertex after the geometry processing. , The computational load is higher than in Process 1 without this process.

The vertex color (luminance) reflection process is a process of drawing an image reflecting the vertex color value set at each vertex as model information. The vertex color value set at each vertex as model information is subjected to geometry processing. Processing to set the attribute information of the later vertex is required.

Since the processing 2 performs the vertex color (luminance) reflection processing, the calculation load is higher than that of the processing 1 without this processing.

The reflection processing performed in the present embodiment is a processing for expressing the reflection of light according to the direction of the surface with respect to the virtual camera.
A reflection calculation based on the direction of each surface and the direction of the virtual camera (viewing direction) is required. Specifically, the orientation of each surface is determined by the normal vector value of the vertex, so the normal vector given as model information is read to each vertex, and the reflection operation is performed. It is necessary to output it by reflecting it on the vertex color which is information.

Since this reflection processing has a high calculation load, the calculation load of the processing 3 is higher than that of the processing 1 and the processing 2.

As described above, in the present embodiment, rendering processing with different precision is realized by omitting translucent processing, vertex color (luminance) reflection processing, and reflection processing depending on the type of rendering processing.

[0137] 3. FIG. 8 is a flowchart for explaining an operation example of the geometry calculation processing according to the present embodiment.

In this embodiment, step S is executed until the processing is completed for all the objects arranged in the three-dimensional space.
Steps S10 to S70 are repeated.

That is, if the distance between the object and the virtual camera is short, the processing 3 is executed (steps S20 and S6).
0), if the distance between the object and the virtual camera is long, execute processing 1 (steps S30, S40); if the distance between the object and the virtual camera is medium, execute processing 2 (steps S30, S50). ).

FIG. 9 is a flowchart for explaining an operation example of processing 1 of the present embodiment.

In process 1 of the present embodiment, step S1 is performed until the process is completed for all vertices of the given object.
Steps S10 to S180 are repeated.

That is, first, the vertex coordinate value given to each vertex as model information is read (step S12).
0).

Then, a geometric / field-of-view transformation / perspective projection transformation operation for transforming the vertex coordinates into a world coordinate system, a viewpoint coordinate system, and a screen coordinate system is performed (step S130).

Next, an environment mapping calculation process is performed to calculate a reflection direction vector based on the viewpoint position (the position of the virtual camera) and the vertex coordinates to calculate a texture coordinate value for performing environment mapping (step S140).

The calculated texture coordinate value is written as vertex attribute information after the geometry processing (step S150).

Next, the fixed vertex color information is written as the vertex attribute information after the geometry processing (step S).
160). That is, since the vertex color (luminance) reflection process is not performed in process 1, a fixed value may be output, and it is not necessary to read the vertex color of the vertex given as model information. Therefore, the number of accesses and the number of operation steps can be reduced as compared with other processes.

The calculated vertex coordinate values are written as the vertex attribute information after the geometry processing according to the calculation result of step S130 (step S170).

FIG. 10 is a flow chart for explaining an operation example of the processing 2 of the present embodiment.

In process 2 of the present embodiment, step S2 is performed until the process is completed for all vertices of the given object.
Steps S10 to S310 are repeated.

That is, first, the vertex coordinate value given to each vertex as model information is read (step S22).
0).

Next, a vertex color given to each vertex as model information is read (step S230). Since the vertex color (luminance) reflection process is performed in the process 2, it is necessary to read the vertex colors given to each vertex as model information.

Next, an alpha mapping information value given to each vertex as model information is read (step S).
240). In process 2, since the translucent process is performed, it is necessary to read alpha mapping information given to each vertex as model information.

Then, a geometric / field-of-view transformation / perspective projection transformation operation for transforming the vertex coordinates into a world coordinate system, a viewpoint coordinate system, and a screen coordinate system is performed (step S250).

Next, an environment mapping calculation process is performed to calculate a reflection direction vector based on the viewpoint position (the position of the virtual camera) and the vertex coordinates and to calculate a texture coordinate value for environment mapping (step S260).

Next, an alpha mapping calculation process for calculating an α value necessary for performing the translucency process is performed (step S270).

The calculated texture coordinate value is written as vertex attribute information after the geometry processing (step S280).

Next, the vertex color read in step S230 is written as the attribute information of the vertex after the geometry processing (step S290). That is, in process 1, a fixed value is output because the vertex color (luminance) reflection process is not performed, but in process 2, the vertex color (luminance) of the model is output because the vertex color of the vertex given as model information is output. The reflected vertex color information can be output as the vertex attribute information after the geometry processing.

Then, the calculated vertex coordinate values are written as the vertex attribute information after the geometry processing according to the calculation result of step S250 (step S300).

FIG. 11 is a flow chart for explaining an operation example of the processing 3 of the present embodiment.

In the process 3 of the present embodiment, steps S4 and S4 are executed until the process is completed for all vertices of the given object.
Steps S10 to S520 are repeated.

That is, first, the vertex coordinate value given to each vertex as model information is read (step S42).
0).

Next, an alpha mapping information value given to each vertex as model information is read (step S).
430). In the process 3, since the translucent process is performed, it is necessary to read the alpha mapping information given to each vertex as the model information.

Next, a normal vector value given to each vertex as model information is read (step S440). In the process 3, since the reflection process is performed, it is necessary to read a normal vector value given to each vertex as model information.

Then, a geometric / field-of-view transformation / perspective projection transformation operation is performed to transform the vertex coordinates into the world coordinate system, the viewpoint coordinate system, and the screen coordinate system (step S450).

Next, an environment mapping calculation process is performed to calculate a reflection direction vector based on the viewpoint position (the position of the virtual camera) and the vertex coordinates and calculate a texture coordinate value for performing environment mapping (step S460).

Next, an alpha mapping calculation process for calculating an α value necessary for performing the translucent process is performed (step S470).

Next, reflection calculation processing for expressing the reflection of light according to the direction of the surface with respect to the virtual camera is performed (step S480). In the reflection calculation processing, light reflection is calculated based on the normal vector of the read vertex and the direction of the virtual camera (line-of-sight vector), and the calculation result is reflected on the vertex color, which is the attribute information of the vertex after the geometry processing. Since the reflection processing has a high calculation load, the calculation load of the processing 3 is higher than that of the processing 1 and the processing 2.

Then, the calculated texture coordinate value is written as vertex attribute information after the geometry processing (step S490).

Next, the vertex color calculated in step S480 is written as the vertex attribute information after the geometry processing (step S500). As a result, it is possible to set a luminance value reflecting the direction of the surface with respect to the virtual camera in the vertex color.

The calculated vertex coordinate value is written as the vertex attribute information after the geometry processing according to the calculation result of step S450 (step S520).

[0171] 4. Hardware Configuration Next, an example of a hardware configuration capable of realizing the present embodiment will be described with reference to FIG.

The main processor 900 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 physical simulation for moving or moving an object requires processing such as matrix operation, a program operating on the main processor 900 instructs the coprocessor 902 to perform the processing (request ).

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

The data decompression processor 906 performs a decoding process for decompressing the compressed image data and sound data, and performs a process for accelerating the decoding process of the main processor 900. 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, bilinear filtering, 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.

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

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

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

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

The DMA controller 970 is a device for controlling the DM between the processor and the memory (RAM, VRAM, ROM, etc.).
A transfer is controlled.

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

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

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

When each means of the present invention is executed by both hardware and a program, 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. 13A 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. 13B shows an example in which the present embodiment is applied to a home game system. The player enjoys the game by operating the game controllers 1202 and 1204 while watching the game image projected on the display 1200. In this case, the storage information is stored in a CD 1206 or a memory card 1208, 1209, which is an information storage medium detachable from the main system.

FIG. 13C shows a host device 1300,
The host device 1300 and the network 1302 (LA
N or a wide area network such as the Internet).
An example in which the present embodiment is applied to a system including 4-1 to 1304-n will be described. In this case, the storage information is, for example, a magnetic disk device that can be controlled by the host device 1300,
It is stored in an information storage medium 1306 such as a magnetic tape device and a memory. If the terminals 1304-1 to 1304-n are capable of generating a game image and a game sound in a stand-alone manner, the host device 1300 outputs the game image and the game sound.
A game program or the like for generating game sounds is transmitted to the terminal 1.
It is delivered to 304-1 to 1304-n. On the other hand, if it cannot be generated stand-alone, the host device 1300 generates a game image and a game sound, and transmits them to the terminals 1304-1 to 1304-1.
1304-n and output at the terminal.

In the case of the configuration shown in FIG. 13C, each means of the present invention may be executed by distributing between a host device (server) and a terminal. Further, the storage information for executing each means of the present invention may be stored separately in an information storage medium of a host device (server) and an information storage medium of a terminal.

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

The present invention is not limited to 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 may be made dependent on another independent claim.

In the above embodiment, the case where the type of rendering processing is selected based on the distance between the object and the virtual camera has been described as an example, but the present invention is not limited to this. For example, the type of rendering processing may be selected based on the degree of influence of the light source on the object, or the type of rendering processing may be selected based on the arrangement of the object, the light source, and the virtual camera. When an image is generated by generating objects of a plurality of sizes having different magnifications based on the magnification, a type of the rendering process may be selected based on the magnification.

The present invention can be applied to various games (fighting games, shooting games, robot battle games, sports games, competition games, role playing games, music playing games, dance games, etc.).

The present invention can be applied to various game systems such as arcade game systems, home game systems, large attraction systems in which many players participate, simulators, multimedia terminals, and system boards for generating game images. .

[Brief description of the drawings]

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

FIG. 2 is an image showing a state of a school of fish in water.

FIGS. 3A to 3C are diagrams for explaining a relationship between rendering processing with different degrees of precision and a processing load; FIG.

FIGS. 4A and 4B are diagrams for explaining the relationship between the distance of an object from a virtual camera and the precision of rendering processing.

FIGS. 5A and 5B are diagrams for explaining an image example that can be realized with the same processing load.

FIG. 6 is a diagram for describing a case where rendering processing is performed on an object having given model information arranged in a three-dimensional space in the present embodiment.

FIG. 7 is a diagram for describing a type of rendering processing of each geometry processing routine.

FIG. 8 is a flowchart illustrating an operation example of a geometry calculation process according to the present embodiment.

FIG. 9 is a flowchart for explaining an operation example of processing 1 of the present embodiment.

FIG. 10 is a flowchart for explaining an operation example of Process 2 of the present embodiment.

FIG. 11 is a flowchart for explaining an operation example of processing 3 of the present embodiment.

FIG. 12 is a diagram illustrating an example of a hardware configuration capable of realizing the present embodiment.

FIGS. 13A, 13B, and 13C are diagrams showing 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 112 movement / motion calculation unit 114 viewpoint distance calculation unit 130 image generation unit 132 geometry processing unit 134 processing type selection 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 save information storage device 196 communication unit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C001 BA00 BA05 BA06 BC00 BC05 BC06 BD05 CA01 CA05 CB01 CB06 CC02 CC03 CC08 5B050 BA07 BA08 BA09 CA07 EA24 EA30 FA02 5B080 AA13 FA03 FA17 GA11 GA22 9A001 HH29 HH32 JJ76

Claims (30)

[Claims] 1. A game system for generating an image, wherein when generating an image of a given frame, a type of rendering process is performed for each object from a plurality of different types of rendering processes based on given conditions. And a means for performing a rendering process in accordance with the selected type for each object to generate an image of the given frame. 2. A game system for generating an image, comprising: a plurality of objects arranged in a three-dimensional space;
Means for determining the type of rendering the object for each object based on given conditions; and performing rendering processing with different degrees of precision in accordance with the type determined for each object, A game system, comprising: means for generating an image. 3. The method according to claim 1, wherein at least one of a texture mapping process, a reflection process, a shading process, a light source process, and a translucent process is omitted according to the type of the rendering process. Alternatively, a game system characterized by performing rendering processing in a simplified manner. 4. A geometry calculation means according to claim 1, wherein a geometry calculation is performed by using attribute data given to the definition point of the object to generate attribute data of the definition point required at the time of drawing. Drawing means for drawing an object based on the attribute data of the definition point required at the time of drawing, wherein the geometry calculation means includes:
A game system, wherein a process of generating attribute data other than a definition point coordinate is simplified according to a type of the rendering process to perform a geometry calculation. 5. The method according to claim 4, wherein the geometry calculation means includes:
It has a plurality of processing routines with different algorithms for generating attribute data other than the definition point coordinates, and performs a calculation by selecting a given routine according to the type of the rendering processing. Game system. 6. A geometry calculation means according to claim 1, wherein a geometry calculation is performed on the basis of the attribute data given to the definition point of the object to generate attribute data of the definition point required at the time of drawing. A rendering processor for performing rendering processing based on attribute data of defined points required at the time of rendering, wherein the geometry calculation means includes: a color, a luminance, an α value, and mapping information given to a defined point of an object in a three-dimensional space. Value, for the process of generating attribute data of the definition point required at the time of drawing using at least one attribute data of normal line information information, a plurality of processing routines having different execution step number or execution access number, Depending on the type of the rendering processing, the processing routine is terminated. A game system characterized by performing processing by switching. 7. The game system according to claim 1, wherein the given condition includes a condition relating to a distance between the object and the virtual camera. 8. The game system according to claim 1, wherein the given condition includes a condition relating to a degree of influence of the light source on the object. 9. The game system according to claim 1, wherein the given condition includes a condition relating to an arrangement of an object, a light source, and a virtual camera. 10. The image processing apparatus according to claim 1, wherein the given condition relates to a case where a plurality of objects having different magnifications are generated based on the same model to generate an image. A game system comprising a condition. 11. The color information of a defined point of an object after geometry processing based on color information given as attribute information to a defined point of the object when performing a geometry operation. Alternatively, a game system which performs a calculation process for generating luminance information in a simplified manner according to the type of the rendering process. 12. The method according to claim 1, wherein at the time of performing a geometry operation, at least one of a normal vector, a virtual camera direction, and a light ray direction provided as attribute information at a definition point of the object. A game system, wherein a calculation process of generating color information or luminance information of a defined point after a geometry process in accordance with a degree of light reflection calculated based on the type of the rendering process is performed in a simplified manner. . 13. The method according to claim 1, wherein, when performing the geometry calculation, the object after the geometry processing is rendered semi-transparently based on the α value given as attribute information to the defined point of the object. A game system for performing an arithmetic process for generating an alpha value required for a game in accordance with the type of the rendering process. 14. The game system according to claim 1, wherein a rendering process is performed by omitting a process of mapping an environment of an object according to the type of the rendering process. 15. The game system according to claim 1, wherein the number of times of performing texture mapping on an object is changed according to the type of the rendering process to perform the rendering process. 16. An information storage medium that can be used by a computer, wherein a plurality of different types of rendering processes are performed for each object based on given conditions in generating an image of a given frame. Means for selecting the type of; and means for performing a rendering process according to the selected type for each object to generate an image of the given frame; and a program for executing Information storage medium. 17. An information storage medium usable by a computer, comprising: a plurality of objects arranged in a three-dimensional space;
Means for determining the type of rendering the object for each object based on given conditions; and performing rendering processing with different degrees of precision in accordance with the type determined for each object; An information storage medium comprising: means for generating an image; and a program for executing: 18. The method according to claim 16, wherein at least one of a texture mapping process, a reflection process, a shading process, a light source process, and a translucent process is omitted according to the type of the rendering process. Alternatively, an information storage medium including a program for performing a rendering process in a simplified manner. 19. The geometry calculation means according to claim 16, wherein a geometry calculation is performed using attribute data given to the definition point of the object to generate attribute data of the definition point required at the time of drawing. A program for executing drawing means for drawing an object based on the attribute data of the defined points required at the time of drawing, wherein the geometry calculation means includes:
An information storage medium comprising a program for performing a geometry operation by simplifying a process of generating attribute data other than a definition point coordinate according to a type of the rendering process. 20. The method according to claim 19, wherein the geometry calculation means includes:
It has a plurality of processing routines with different algorithms for generating attribute data other than the definition point coordinates, and includes a program for selecting a given routine and executing an operation according to the type of the rendering processing. An information storage medium characterized by the above-mentioned. 21. A geometry calculation means according to claim 16, wherein a geometry calculation is performed based on the attribute data given to the definition point of the object to generate attribute data of the definition point required at the time of drawing. A program for executing a drawing processor for performing a drawing process based on the attribute data of the definition point required at the time of the drawing, wherein the geometry calculation means includes: a color and a luminance given to the definition point of the object in the three-dimensional space. , Α value, mapping information value, and normal line information information, at least one of attribute data of a defined point required at the time of drawing is generated using a plurality of steps having different numbers of steps or times of access at the time of execution. Processing routine; An information storage medium characterized by including a program for executing the processing by switching the processing routine according to the program. 22. The information storage medium according to claim 16, wherein the given condition includes a condition relating to a distance between the object and the virtual camera. 23. The information storage medium according to claim 16, wherein the given condition includes a condition relating to a degree of influence of the light source on the object. 24. The information storage medium according to claim 16, wherein the given condition includes a condition relating to an arrangement of an object, a light source, and a virtual camera. 25. The image processing apparatus according to claim 16, wherein the given condition is related to the magnification when a plurality of objects having different magnifications are generated based on the same model to generate an image. An information storage medium characterized by including a condition. 26. The color information of the object definition point after the geometry processing based on the color information given as attribute information to the object definition point when performing the geometry operation according to any one of claims 16 to 25. Alternatively, an information storage medium including a program for executing arithmetic processing for generating luminance information in a simplified manner according to the type of the rendering processing. 27. The method according to claim 16, wherein at the time of performing a geometry operation, at least one of a normal vector, a virtual camera direction, and a light ray direction given as attribute information to a definition point of the object. Including a program for simplifying, according to the type of the rendering processing, an arithmetic processing for generating color information or luminance information of a defined point after the geometric processing according to the degree of light reflection calculated based on the type of the rendering processing An information storage medium characterized by the following. 28. The method according to claim 16, wherein, when performing the geometry operation, the object after the geometry processing is rendered semi-transparently based on the α value given as attribute information to the defined point of the object. An information storage medium including a program for simplifying an arithmetic process for generating an alpha value required for the rendering process according to the type of the rendering process. 29. The program according to claim 16, further comprising a program for executing a rendering process by omitting a process of performing an environment mapping of an object according to the type of the rendering process. Information storage medium. 30. A program according to claim 16, further comprising a program for executing a rendering process by changing the number of times texture mapping is performed on an object according to the type of the rendering process. Information storage medium.