JP3470966B2 - Program, information storage medium, and game system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to game information, an information storage medium storing game information, and a game system.

[0002]

2. Description of the Related Art With the increase in processing speed of computers and game devices, the number of polygons that can be drawn has increased and it has become possible to express more precise models. In addition, it has become possible to accurately express not only the model but also the shadow of the model. By the way, the shadow does not play a central role in the progress of the game, but is an additional element. However, when realistically expressed according to the movement of the model and the like, the entire image is tightened and felt as a more precise image, so the influence of the shadow on the entire image is significant.

By the way, in computer graphics, when expressing a particle system such as clouds, smoke, and haze, each particle (particle) is drawn one by one. 1 inter (1/60 seconds)
Due to the restriction of drawing inside, it is difficult to draw each particle one by one. For this reason, it is common to map a texture that represents an aggregate of particles onto a single plate-shaped polygon and to express a particle system simply by arranging a plurality of such plate-shaped polygons. Has been done.

For example, consider the case of expressing a cloud object, which is a typical example of a particle system. When expressing a cloud object, generally, plate-shaped polygons are arranged horizontally at a predetermined altitude above the virtual space. Then, a texture representing a cloud is mapped to this polygon. By such processing, the cloud object can be expressed easily.

[0005]

However, there are the following problems in expressing the shadow of the particle system. That is,
Since particle systems are generally represented in a wide area,
It is difficult to specify the location where the shadow is applied. Even if the location where the shadow hits can be specified, if the location where the shadow hits is inclined, raised or depressed, it takes a considerable amount of time for rendering processing to reflect the shadow Met.

In the method of expressing the shadow of the model described above, the place where the shadow falls is a soccer field, a baseball field,
It was a flat place in the building and was not expressed on a place such as a rocky mountain or gravel road. Furthermore, when expressing the shadow of a model, it is necessary to express one shadow for one model, but this shadow is usually drawn by performing α composition (color composition using transparency). For this reason, when a plurality of models overlap, there is a problem that the shadows of the respective models are α-combined and the shadow of the overlapping portion is expressed deeply.

The problem of the present invention is that regardless of the shape of the terrain,
It is to express shadows easily, and to express overlapping shadows such as models without contradiction.

[0008]

In order to solve the above-mentioned problems, the first invention generates a virtual space image based on a given viewpoint on a system by calculation and control by a processor. Game information for executing a given game (for example, the game program 410 of FIG. 12), which represents a distribution of a given object arranged on the terrain area set in the virtual space and / or in the sky. Plane information (for example, cloud distribution map data 430 in FIG. 12)
And a reflecting means for reflecting the shadow of the given object in the terrain area based on the plane information (for example, the cloud shadow reflecting unit 321 in FIG. 12). Information (for example, the cloud shadow expression program 411 in FIG. 12).

A ninth aspect of the invention is a game system (for example, the game apparatus 10 in FIG. 12) that generates a virtual space image based on a given viewpoint and executes a given game. Based on the plane information, generation means for generating plane information (for example, cloud distribution map data 430 in FIG. 12) representing the distribution of a given object arranged on the set terrain area and / or in the sky. Reflecting means (for example, cloud shadow reflecting unit 321 in FIG. 12) for reflecting the shadow of the given object in the topographic area is provided.

According to the first or ninth aspect of the invention , the plane information represents the distribution of objects arranged on the topographic area and / or the sky, and based on this, the shadow of the object is displayed on the topographic area. Reflected. For this reason, the shadow of the object can be easily reflected in any terrain area.

That is, regardless of the shape of the topography, whether it is raised, depressed, or inclined,
A distribution of objects arranged on the topographic area and / or in the sky is generated as information relating to a two-dimensional plane. For this reason, by projecting the plane information in parallel, for example, it becomes possible to easily express the shadow of the object regardless of the terrain shape.

In addition, each object can be shaded at one time based on plane information, rather than being shaded on the terrain area. That is, by reflecting the shadow of each object, it is possible to avoid a contradiction such that the shadow overlap portion becomes dark.

In addition to the particle system, the given object may be a model of a character or the like, but the given object is specified as in the second or tenth invention. It is good as well.

That is, according to a second aspect of the present invention, in the game information of the first aspect, the given object is a cloud-like object, and the cloud-like object is arranged above the terrain area based on the plane information. Placement means (e.g.,
12 includes information for causing the system to function the cloud placement unit 314) of FIG.

The tenth invention is the game system according to the ninth invention , wherein the given object is a cloud-like object, and the cloud-like object is arranged above the topographic area based on the plane information. arranging means (e.g., cloud arrangement section 314 of FIG. 12), der which comprises
The

Here, the cloud object is, for example, “cloud”.
An object that represents a particle system expressed in a certain range, such as “smoke” or “smoke”.

According to the second or tenth invention , a given object can be a cloud-like object, and the following effects can be obtained. That is, based on the plane information, a cloud-like object can be arranged above the terrain area, and the shadow of the cloud-like object can be reflected in the terrain area. In other words, a shadow conforming to the shape of the cloud-like object placed in the sky is represented on the terrain area. Therefore, for example, when a cloud floating in clear weather is viewed from above in the virtual space, the shape of the cloud and the shape of the shadow of the cloud on the terrain area are expressed in the same way. The shadow on the system can be expressed more realistically and easily.

Also, the third invention is the first or second invention.
In the clear game information, a given two-dimensional plane (for example, a horizontal plane in the virtual space) of the terrain area is defined as a unit area (for example, 10 m × 10 m in the horizontal direction of the virtual space).
Information for causing the system to function, and the generation means includes, in the plane information, at least the topography area corresponding to each unit area and / or the sky. Information indicating the presence or absence of an object (for example, information indicating whether or not it exists as a digital value of 1/0, or information indicating the presence as an analog value of 1 to 0 (for example, transparency)) Information for generation including the information, and the reflection means includes information for reflecting the shadow of the given object on the terrain area corresponding to the unit area for each unit area.
It is.

Also, the fourth invention is the first or second invention.
In light of the game information, said given two-dimensional plane of the terrain area (e.g., a horizontal plane in the virtual space), the height information of each grid point (e.g., elevation in the virtual space) allocation means for allocating a two-dimensional lattice with By connecting the information for causing the system to function and the coordinates of each grid point assigned to the topographical area of the two-dimensional grid,
Information for causing the system to function terrain forming means for forming terrain in the terrain area, and the generating means include, on the plane information, at least on the terrain area corresponding to each grid of the two-dimensional grid and Information indicating the presence / absence of the given object in the sky (for example, expressing whether it exists or not as a digital value of 1/0,
Information for generating including the degree of existence as an analog numerical value of 1 to 0 (for example, information expressed as transparency), and the reflection means correspond to the lattice for each lattice of the two-dimensional lattice Information for reflecting the shadow of the given object on the terrain area to be performed .

According to the third or fourth invention , the shadow of a given object can be expressed more easily. That is, for each unit area ( third invention ) or lattice (fourth invention), information relating to the presence or absence of a given object is included in the plane information. Therefore, when reflecting the shadow of a given object on the terrain area, it is possible to determine whether to reflect the shadow for each unit area or grid. Moreover, in addition to whether or not to reflect a shadow, in the case of reflecting, it is also possible to perform processing such as giving a given color on the terrain area corresponding to the unit area or grid, making the object's shadow even easier. Can be expressed.

According to the third aspect of the present invention , the plane information can be generated after the terrain area is divided into unit areas, so that the shape of the terrain area is not considered. In addition, the shadow of the object can be generated.
Further, according to the fourth invention , since the unit area of the third invention corresponds to a grid, the effect of the third invention is provided, and the topography of the topographic area is also formed by a two-dimensional grid. The processing related to the entire generation can be performed rationally and efficiently.

The fifth aspect of the invention is that of the first to fourth aspects.
Including in any of the game information, wherein the reflecting means, the position on the terrain area to reflect the shadow of the given object, the information for determining on the basis of a given light source
It is a waste.

According to the fifth aspect, the shadow of a given object can be reflected at an appropriate position in accordance with the light source set in the virtual space. For example, when the shadow of a cloud that floats above the virtual space is reflected on the terrain area, the position of the cloud shadow changes depending on the position of the sun. In the plane information, although the presence or absence of a cloud (a given object) existing in the sky over the terrain region is expressed, only the existence position thereof is represented.
The shadow of a given object can be reflected at an appropriate position according to the light source.

According to a sixth aspect of the present invention , there is provided game information for causing a system to generate a virtual space image based on a given viewpoint and to execute a given game by calculation and control by a processor. Generating means for generating plane information representing at least a shadow of a given object arranged in the terrain area and / or sky set in the virtual space in association with the arrangement position of the object; Based on the information, the reflecting means for reflecting the shadow of the given object in the terrain area includes information for causing the system to function .

An eleventh aspect of the present invention is a game system for executing a given game by generating an image of a virtual space based on a given viewpoint, and at least on a terrain area set in the virtual space and / or Generating means for generating a plane information representing a shadow of a given object placed in the sky in association with a placement position of the object; and a shadow of the given object based on the plane information And reflecting means for reflecting in the above .

According to the sixth or eleventh invention , the shadow of the object arranged on the topographic area and / or the sky is represented in the plane information in association with the arrangement position of the object. Object shadows are reflected in the terrain area. For this reason, the shadow of the object can be easily reflected in any terrain area.

That is, regardless of the shape of the terrain, whether it is raised, depressed, or inclined,
The shadow of the object arranged on the topographic area and / or the sky is generated as information related to a two-dimensional plane associated with the arrangement position. Therefore, by projecting this plane information in parallel, for example, it is possible to easily express the shadow of the object regardless of the topographic shape.

Further, each object can be shaded once based on plane information, instead of being shaded on the terrain area. That is, by reflecting the shadow of each object, it is possible to avoid a contradiction such that the shadow overlap portion becomes dark.

According to a seventh aspect of the present invention, in the game information of the sixth aspect, the generating means generates plane information representing the shadow of the given object based on the given light source. It contains information .

According to the seventh aspect, the shadow of the object represented by the plane information is based on the light source set in the virtual space. Therefore, for example, when the object is a model related to a soccer player, the terrain area is a soccer field, and an image of a night game is generated, a plurality of light sources can be set. In this case, by expressing the shadows from a plurality of light sources in the plane information, the shadows of the light sources with respect to the light beam direction can be expressed without contradiction. Further, the difference between shadows such as a main shadow and a penumbra generated by a surface light source or the like can be expressed without contradiction.

Further, the eighth invention, the information storage medium der for storing any of the game information of the seventh invention of the first
The

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. In the following description, an airplane game will be described as an example, but the application of the present invention is not limited to this. In addition, the method of expressing the shadow of “clouds” will be described. Of course, the same can be applied to objects that have the same shape as clouds, such as “smoke” and “haze”. .

FIG. 1 is a diagram showing an example in which the present invention is applied to a home game machine. While the game is running, a state (game screen) in the game space based on the viewpoint set at the cockpit of the airplane is displayed on the display 1200. In the figure, the player plays a display 1200.
While watching the game image displayed on the screen, the user can enjoy the airplane game by operating the airplane using the game controllers 1202 and 1204. In this case, the information necessary for playing the game such as the game program 410 is a CD-ROM which is an information storage medium that can be attached to and detached from the main unit.
(Or DVD-ROM) 1206, an IC card, or memory cards 1208, 1209, etc.

Here, operating the airplane means instructing the direction, speed, etc. of the airplane that is virtually arranged in the game space. The game space is a virtual three-dimensional space expressed by a world coordinate system, that is, an XYZ orthogonal coordinate system. In the following description, unless otherwise specified, coordinate values are expressed in the world coordinate system. For the sake of simplicity, the game screen does not take into account objects related to the aircraft, such as the state of the cockpit or window glass.
Only the state seen from the cockpit (topography seen from the viewpoint) is displayed.

First, the principle of this embodiment will be described. FIG. 2 is a schematic diagram showing the relationship between the terrain and the clouds in the game space. As shown in the figure, Terrain Map 2
In the sky above 0, an object representing a cloud (cloud object 31) is arranged.

The terrain map 20 will be described in detail later, but a two-dimensional grid is assigned to the ground plane, and the elevation values obtained for each grid point are connected to form a polygon to form the terrain three-dimensionally. To express. FIG.
In FIG. 2, the terrain map 20 shows a state in which a two-dimensional lattice is assigned at a density of 256 × 256 lattices.

The cloud object 31 is constituted by mapping a texture representing a cloud (hereinafter referred to as a cloud distribution map 30) onto a single plate-like object having the same size as the topographic map 20. . And
The cloud object 31 is arranged at a predetermined altitude above the ground plane so as to be parallel to the ground plane.

The cloud distribution map 30 mapped to the cloud object 31 does not have an RGB value, but has a texture having only an α value (in this embodiment, it represents opacity) (hereinafter referred to as an α texture). ). For each texel, the cloud distribution is expressed by an α value set according to the presence / absence of the cloud. Specifically, for each texel, a value greater than “0” and less than or equal to “1” is set as the α value for a portion with a cloud, and “0” is set for a portion without a cloud. At the time of drawing, an RGB value representing the cloud, that is, (255, 255, 255) representing “white” is given to represent the cloud.

In FIG. 2, in order to make it easy to visually grasp the cloud distribution, the texel in which the α value is set to “1” or “0” and the α value is set to “1”. (The part with the cloud) is indicated by “black”, and the texel (the part without the cloud) in which the α value is set to “0” is indicated by “white”. The cloud distribution map 30 has a resolution equal to the density of the two-dimensional grid assigned to the topographic map 20, that is, a resolution of 256 × 256 texels.

Incidentally, the topographic map 20 and the cloud distribution map 30 are composed of equal density (resolution), that is, 256 × 256 (lattice or texel). For this reason, the grids constituting the topographic map 20 and the texels constituting the cloud distribution map 30 correspond one-to-one.

More specifically, the grid of the terrain map 20 existing vertically below the texels constituting the cloud distribution map 30 is a grid corresponding to the texels. Conversely,
It can also be said that the texel of the cloud distribution map 30 existing in the vertical upward direction of the grid constituting the topographic map 20 is the texel corresponding to the grid.

As described above, the texels constituting the cloud distribution map 30 and the grids constituting the topographic map 20 have a one-to-one correspondence. Therefore, when a certain grid or texel is specified, the texel is immediately Corresponding texels or grids can be identified.

Next, regarding cloud shadows expressed on the terrain,
explain. In the present invention, based on the cloud distribution map 30, the state of cloud distribution, that is, the presence / absence of clouds is reflected in the terrain map 20 as it is to express cloud shadows on the terrain. Specifically, whether or not to express a cloud shadow in the corresponding grid is determined according to the presence / absence of each texel, that is, the α value. Conversely, whether or not a cloud shadow is expressed in each grid is the presence or absence of the corresponding texel cloud,
In other words, it can be determined by the α value.

As described above, the texels constituting the cloud distribution map 30 and the grid constituting the topographic map 20 have a one-to-one relationship.
Therefore, cloud shadows generated by parallel projection of cloud objects are represented on the terrain.

The expression of cloud shadows in each grid is specifically performed as follows. At the time of drawing, in each grid of the terrain map 20, the RGB values that the grid has,
RGB value representing the color of the cloud, ie 'black' (0,0,
0) based on the α value set in the texel of the cloud distribution map 30 corresponding to the lattice. Then, this synthesis result is converted into color information (RGB
Value).

That is, for texels (parts with clouds) where the α value is set to “1”, the RG of the corresponding grid
The B value is updated to an RGB value representing the color of the cloud shadow, that is, (0, 0, 0) representing “black”. Further, for texels (parts where there is no cloud) for which the α value is set to “0”, the RGB values of the corresponding grid are not particularly changed. in this way,
Only for the texel with α value set to “1”, that is, the part with cloud, the RGB value of the corresponding grid is updated to (0,0,0) representing “black”, and the cloud shadow is expressed. Will be. Further, for example, for a texel (a portion having a cloud) in which the α value is set to “0.8”, the RGB value (R, G, B) × (1−
0.8) and the RGB value (0,0,0) × 0.
8 and sum. That is, a cloud shadow having a color that slightly retains the color of the terrain is expressed.

As described above, in order to determine whether or not to express a cloud shadow on the terrain for each texel constituting the cloud distribution map 30, regardless of the shape of the terrain such as a ridge,
The position where the cloud shadow is expressed can be easily specified, and the cloud shadow can be expressed. In addition, since the cloud shadow is expressed based on the α value set in the cloud distribution map 30, a cloud shadow having the same shape as the cloud shape can be expressed on the terrain.

By the way, while the game is being executed, a perspective projection conversion process is performed on each polygon constituting the object and the like to generate a game image. For this reason, by omitting the drawing of an object existing at a certain distance or more from the viewpoint, the processing load related to the drawing may be reduced. In the airplane game according to the present embodiment, since the viewpoint moves freely in the game space, it is important to specify the drawing area because of processing time constraints. Therefore, in the present embodiment, terrain is formed based on the terrain map and drawn for a certain region centered on the viewpoint (hereinafter referred to as a target region).

FIG. 3 is a diagram showing a state where the target area 40 is set in the terrain map 20. This target area 40 is
It is an area of a predetermined size specified based on the position of a virtual camera 41 (hereinafter referred to as viewpoint 41) set in the game space. In the figure, the target area 40 is the viewpoint 4.
1 (specifically, this is the position when the height of the viewpoint 41 is expressed as “0” on the ground plane, and hereinafter referred to as the viewpoint ground plane position). .

Further, a grid constituting the topographic map 20;
There is a one-to-one correspondence with the texels that make up the cloud distribution map 30. Therefore, when the target region 40 is specified, the range of the cloud distribution map 30 corresponding to the target region 40, that is, the range of the cloud distribution map composed of 64 × 64 texels can be specified immediately. Hereinafter, the cloud distribution map in the specified range is referred to as a cloud texture 50. Of course, the cloud texture 50 is a texture formed by texels corresponding to each of the lattices constituting the target region 40. That is, the cloud texture 50 corresponds to the target area 4.
It can be said that the texture is located above 0 and has the same size as the target area 40.

Next, the topographic map 20 and the cloud distribution map 3
Details of 0, the target area 40, and the cloud texture 50 will be described.

First, the expression of the three-dimensional landform in the game space will be described. The three-dimensional landform expression method in this embodiment is known as a technique for expressing a landscape. This technique assigns a grid with a given spacing to the ground plane,
By giving altitude data to each grid point of the 2D grid, the 3D terrain is expressed with less data.

That is, by connecting elevation points (hereinafter referred to as polygon vertices) given to each grid point, a polygon is formed to express a three-dimensional landform. Since this polygon forms a three-dimensionally inclined plane in accordance with the elevation difference between the respective polygon vertices, it is possible to express the terrain three-dimensionally with these polygons. In addition, since the grid points are regularly arranged, the data necessary for expressing the three-dimensional landform is only the elevation data of the polygon vertices.

FIG. 4 is a diagram showing an example of the three-dimensional landform expressed by the above method. In FIG. 4, the ground plane (X
On the -Z plane), a two-dimensional lattice is assigned by dividing each of them along the X-axis and Z-axis directions at a constant interval W. A three-dimensional landform is represented by polygons formed by polygon vertices Q corresponding to the respective lattice points.

FIG. 5 shows an example of the topographic map 20. FIG. 5 shows a state in which the topographic map 20 to which a two-dimensional lattice is assigned at a density of 256 × 256 lattices is viewed from the Y-axis direction. As shown in FIG.
Coordinate points A1 [0,0,0], A on the ground plane (XZ plane)
In a square area having apexes 2 [L, 0,0], A3 [L, 0, L], A4 [0,0, L], the length of one side is W (= L / 25
6) is constituted by a plurality of lattices R.

The origin O is defined as the lattice point P _0,0 , and the lattice point P existing nth in the X-axis direction and mth in the Z-axis direction is denoted as P _nm, and is defined as the lattice point P _nm . The corresponding polygon vertex Q is denoted as Q _nm . Also, the elevation values of the respective lattice points P _nm, denoted as h _nm. However, n, m =
0, 1,..., 256. Further, the grid that is Nth in the X-axis direction and Mth in the Z-axis direction from the coordinate point A1 (origin O) is denoted as _RNM . That is, lattice point P
Lattice R surrounded by _{N-1, M-1} , P _{N-1, M} , P _{N, m} , P _{N-1, M}
Becomes _RNM . However, N, M = 1, 2,..., 25
6.

Next, the structure of the terrain data will be described. FIG. 6 is a diagram illustrating an example of terrain data. In FIG. 6, terrain data for representing the terrain map 20 shown in FIG. 5 is shown. As shown in FIG. 6, the terrain data includes lattice points P formed on the ground plane (XZ plane).
for each _nm, elevation values h _nm of the grid points P _nm are stored.

[0058] That is, this terrain data, the coordinate values of the polygon vertices Q _nm for representing three-dimensional topography [x, y,
z] will be given as: x = nW y = h _nm z = mW

In this way, a polygon is formed by connecting the polygon vertices Q _nm given based on the terrain data, and the terrain in the terrain map 20 is expressed.

FIG. 7 is a diagram showing an example of the cloud distribution map 30. In FIG. 7, a cloud distribution map 30 corresponding to the topographic map 20 shown in FIG. 5 is shown. As shown in FIG. 7, the cloud distribution map 30 has a vertical direction (M direction) in the figure,
And a texture having a resolution of 256 texels in the horizontal direction (N direction), that is, 256 × 256 texels. The texel T at the upper left in the figure is T _1,1 , the Nth in the horizontal direction (N direction), and the vertical direction (M direction)
The texel T existing in the Mth is denoted as _TNM . However, N, M = 1, 2,..., 256. Further, the texels T _NM in the cloud distribution map 30 respectively correspond to the two-dimensional lattice R _NM of the topographic map 20 shown in FIG.

Further, as described above, the cloud distribution map 30 is an α texture having no RGB value and only an α value. The α value set for each texel T represents the density of the distributed cloud (with / without cloud), and any value from “0” to “1” is set. . Specifically, “0” is set to the portion where there is no cloud, and a value closer to “1” is set as the α value as the distributed cloud becomes darker.

That is, the cloud distribution map 30 shows the texels T
Is represented by the cloud distribution (with / without clouds) in the corresponding terrain map 20. Also, when drawing, basically an RG expressing clouds
By giving a B value, ie, (255, 255, 255) representing “white”, a cloud is represented.

Next, the target area 4 in the topographic map 20
The setting of 0 will be described. While the game is running, the viewpoint F is determined for each frame based on the position of the player's own device in the game space (determined based on the player's operation instruction). The coordinate value of this viewpoint F is expressed as [F _X , F _Y , F _Z ].
And Then, as shown in FIG. 8A, the position of the viewpoint when the height F _Y of the viewpoint F is expressed as “0”, that is, the coordinate value of the viewpoint ground plane position F ′ is [F _X , 0, F _Z ].

Next, as shown in FIG. 8B, the grid point P _uv closest to the viewpoint ground plane position F ′ in the terrain map 20 is set as the region center F _P. That is, the coordinate values of the grid points P _uv corresponding to the region around _{F P [x, y, z} ] is as follows. x = uW y = 0 z = vW The target region 40 in the topographic map 20 is set around the region center F _P (grid point P _uv ) determined in this way.

FIG. 9 is a diagram showing an example of the target area 40. 9, the terrain map 20 shown in FIG. 5, the target area 40 set the grid points P _uv as area center F _P is shown. As shown in FIG.
0 is a square region constituted by the lattice R _NM with a density of 64 lattices, that is, 64 × 64 lattices in the vertical direction (Z-axis direction) and the horizontal direction (X-axis direction) in the drawing. However, N = u−31, u−30,..., U + 32, and M = v−31, v−30,.
It is. Also, lattice points _{Pu-32, v-32} , _{Pu + 32, v-32} , P
_{Let u + 32, v + 32} and P _{u-32, v32 be} the vertices B1, B2, B3, and B4 of the target area, respectively.

In this way, the target area 40 based on the viewpoint F
Then, from the topographic data (see FIG. 6), the elevation value h _nm of the grid point P _nm included in the target area 40,
That is, the coordinate value of the polygon vertex Q _nm is given. And
A polygon is formed by connecting these polygon vertices Q _nm, and a three-dimensional landform is formed for the target region 40. That is, during the game, a three-dimensional landform is formed only in the target area 40 set based on the viewpoint F for each frame.

Next, for the formed three-dimensional terrain,
The corresponding terrain texture is mapped. That is, the three-dimensional terrain is colored based on the corresponding terrain texture, and terrain such as “land”, “sea”, and “forest” is expressed.

When the target area 40 is set, the cloud distribution map range corresponding to the target area 40, that is, the cloud texture 50 is specified.

FIG. 10 is a diagram showing an example of the cloud texture 50. 10, the target area 40 shown in FIG.
A cloud texture 50 corresponding to is shown. As shown in FIG. 10, the cloud texture 50 has 64 texels in the vertical direction (M direction) and the horizontal direction (N direction) in the figure,
That is, 64 × 64 texels resolution, a texture composed of texels T _NM. However, N = u−31,
u-30,..., u + 32, and M = v-3
1, v−30,..., V + 32.

The texels T _NM constituting the cloud texture 50 respectively correspond to the grid R _NM of the target area 40 shown in FIG. Moreover, the vertexes C1 to C1 of the cloud texture 50
C4 is the vertex B1 of the target area 40 shown in FIG.
Corresponds to ~ B4.

As described above, when the cloud texture 50 corresponding to the target area 40 is specified, a cloud is arranged on the target area 40 and a cloud shadow is expressed on the terrain.

Specifically, a cloud object 31 to which the cloud texture 50 is mapped is arranged at a predetermined altitude above the target area 40. That is, during the game, clouds (cloud objects 31) are arranged only in the target area 40 set based on the viewpoint F. When drawing the cloud object 31, the RGB representing the cloud
A cloud is represented by giving a value (255, 255, 255) representing 'white'.

In addition, the terrain formed in the target area 40
Then, the cloud texture 50 is mapped. On that occasion
Are the vertices C1 to C4 of the cloud texture 50, respectively.
Vertex B1 to B4 of the target area 40, that is, polygon vertex Q
_u-32,_v-32, Q_{u + 32},_v-32, Q _{u + 32, u + 32}, Q_u-32,_{v + 32}In
By giving, mapping is performed. On this
Thus, cloud shadows are expressed on the terrain formed in the target area 40.
Will be. When drawing terrain, cloud shadows are displayed.
Present RGB value, ie, (0,0,0) representing 'black' is given
As a result, a cloud shadow is expressed.

It should be noted that when the terrain is drawn (cloud shadow expression), the α value set in each texel T _nm constituting the cloud texture 50 may be multiplied by a predetermined coefficient. For example, by multiplying “0.8” as a predetermined coefficient, the α value (opacity) related to the cloud shadow is reduced, and the color of the landform where the cloud shadow is expressed (for example, “blue” of the sea or It is possible to express cloud shadows reflecting the land's 'green'.

As described above, the grid R constituting the topographic map 20 and the texel T constituting the cloud distribution map 30 have a one-to-one correspondence. For this reason, when the target region 40 is set, the cloud distribution map 30 in the range corresponding to the target region 40, that is, the cloud texture 50 can be easily determined. Therefore, the cloud arrangement and cloud shadow expression in the target region 40 can be easily performed from the identified cloud texture 50.

FIG. 11 shows an example of a game image to which the present invention is applied. FIG. 11A is a diagram showing a game image when the cloud texture is not mapped on the three-dimensional landform. FIG. 11B is a diagram showing a game image when a cloud texture is mapped to the three-dimensional landform. That is,
In FIG. 4B, the portion colored with “black” near the horizontal line (near the center of the screen) is a cloud shadow expressed by a cloud texture.

In the mapping of the cloud texture 50 to the terrain, as described above, α composition based on the α value is performed.

For example, when the α composition is α blending, the RGB components (R, G, B) of the terrain are determined as follows. R = α × R _S + (1−α) × R _T G = α × G _S + (1−α) × G _T B = α × B _S + (1−α) × B _T where R _T , G _T and B _T are RGB components (R _T , G _T , B _T ) of the terrain texture mapped to the terrain, and R _S , G _S , B _S are RGB components representing the color of the cloud shadow. (R _S ,
G _S , B _S ), that is, (0, 0, 0) representing 'black'. Α is an α value set in the cloud texture 50.

That is, the density of the cloud shadow expressed on the terrain can be changed according to the density of the cloud. For example, since the α value of the cloud texture 50 is set to be low (a value close to “0”) for the portion where the cloud is thin, the RGB value obtained by the α blending more reflects the RGB value of the terrain texture. Value.

It should be noted that the mapping of the cloud texture to the terrain on which the terrain texture has already been mapped is executed by α synthesis based on the α value set in the cloud texture 50. The cloud texture may be overlaid.
That is, in this case, only the color of the cloud shadow ('black') is given to the portion where the cloud shadow is expressed without reflecting the RGB value of the terrain texture.

As described above, by using the cloud distribution map 30 originally prepared for expressing the cloud distribution, the cloud distribution is expressed and the cloud shadow corresponding to the cloud distribution is expressed. Can be easily realized. In addition, 1
For each frame, the target region 40 is determined based on the position of the viewpoint F, and the cloud texture 50 is specified. For example, even when the cloud distribution changes with time, the cloud shadow can be expressed in accordance with the change. Can be realized.

FIG. 12 is a diagram showing an example of functional blocks of the game apparatus 10 of the present invention. In FIG. 12, functional blocks are an operation unit 100, a display unit 200, and a processing unit 30.
0 and the storage unit 400.

The operation unit 100 is for a player to input operation data, and the function can be realized by hardware such as a lever, a button, and a housing. Also,
When an operation such as pressing the button is performed, the operation signal is output to the processing unit 300. The operation unit 100 is
This corresponds to the game controllers 1202 and 1204 in FIG.

The display unit 200 displays the game image generated by the image generation unit 320. The player inputs operation data (instruction, selection) and the like according to the progress of the game from the operation unit 100 while viewing the game screen displayed on the display unit 200, for example, the game screen shown in FIG. The function of the display unit 200 corresponds to the display 1200 in FIG.

The processing unit 300 performs various processes such as control of the entire game apparatus 10, instructions to each functional unit in the game apparatus 10, game progress processing, image processing, sound processing, and the like. Various processors (CPU, DSP
Etc.) or hardware such as an ASIC (gate array, etc.) or a given program. The processing unit 300 includes a game calculation unit 310 and an image generation unit 3.
20 is included.

The game calculation unit 310 is based on a game space (virtual three-dimensional space) construction process expressed in the world coordinate system, an operation signal from the operation unit 100, a game program 410 read from the storage unit 400, and the like. The process of determining the arrangement position and direction of the enemy aircraft (which is an airplane to be operated by the player) and enemy aircraft, and the hit check of missiles fired by the enemy aircraft and enemy aircraft is executed.

The game calculation unit 310 includes a viewpoint setting unit 311, a target area setting unit 312, and a terrain forming unit 31.
3 and a cloud placement unit 314 are included.

The viewpoint setting unit 311 performs processing for setting the position and orientation of the viewpoint F in the game space based on the arrangement position and orientation of the player. The target area setting unit 312
For each frame, based on the viewpoint F set by the viewpoint setting unit 311, the viewpoint ground plane position F ′ is obtained, and the target region 40 is determined. Based on the terrain data 420, the terrain forming unit 313 performs a process of forming a three-dimensional terrain in the target region 40 set by the target region setting unit 312. The cloud placement unit 314 applies a cloud texture 50 corresponding to the target region 40 set by the target region setting unit 312.
And the cloud object 3 in which the specified cloud texture 50 is mapped above the predetermined altitude of the target region 40.
1 is performed.

The image generating unit 320 performs processing for generating a game image when the game space is viewed from the viewpoint F set by the viewpoint setting unit 311. Specifically, a clipping process for setting a field of view (view volume) by front / rear clipping, a coordinate conversion process for converting the coordinate values of each polygon vertex into a viewpoint coordinate system, a shading process based on the viewpoint F and the position of the light source, A game image is generated by executing rendering processing such as hidden surface (or hidden line) erasing processing. In addition, the image generation unit 320 includes a cloud shadow reflection unit 321.

The cloud shadow reflection unit 321 executes a cloud shadow expression process to be described later according to the cloud shadow expression program 411, and performs a process of coloring the three-dimensional landform formed by the landform forming part 313. Specifically, the cloud texture 50 corresponding to the target region set by the target region setting unit 312 is specified, and the specified cloud texture 50 is mapped to the three-dimensional landform formed by the landform forming unit 313.

The storage unit 400 stores the game program 410.
, Cloud shadow expression program 411 and terrain data 420
And cloud distribution map data 430 are stored.

The terrain data 420 represents the terrain map 20.
For example, as shown in FIG.
Grid point P formed on the ground plane_nmFor each of these grid points
Altitude h _nmIs memorized.

The cloud distribution map data 430 is data relating to the cloud distribution map 30 which is an α texture, and stores α values set in each texel. As described above, the cloud distribution map 30 represents the presence / absence of clouds according to the α value, and indicates the cloud distribution of the entire topographic map 20 as shown in FIG. 11C, for example. FIG.
In (c), a white part represents a part with a cloud, and a black part represents a part without a cloud.

Next, specific processing operations in the game apparatus 10 will be described with reference to the flowchart shown in FIG.

FIG. 13 is a flowchart for explaining an example of processing executed by the processing unit 300 in accordance with the game program 410. Further, this process is performed by the operation unit 1.
This is a process that is executed after the position and direction of its own apparatus are determined by an operation signal from 00, and is a process that is executed for each frame.

In FIG. 13, first, the viewpoint setting unit 311.
Sets a viewpoint F based on the position of the player's own device placed in the game space and its orientation (step S1).

Then, the target area setting unit 312 determines the target area 40 based on the viewpoint F set by the viewpoint setting unit 311 (step S2). Specifically, FIG.
As shown in Fig. 2, the height of the viewpoint F is set to "0" and the ground plane (X
The viewpoint ground plane position F ′ expressed in (−Z plane) is obtained. Then, as shown in FIG. 8 (b), the nearest lattice point P _uv in the viewpoint locations planar position F 'and area center F _P, as shown in FIG. 9, and a density of 64 × 64 grid Target area 40
Set.

Next, the terrain forming unit 313 receives the terrain data.
420, set by the target area setting unit 312
3D terrain is formed in the target area 40 (step S).
3). Specifically, the terrain data 420 is referred to and set.
Grid points P included in the target area 40_nmIs given to
Elevation value h_nmTo get. And the acquired altitude value h _nm
(Polygon vertex Q_nm)
Form a Ligon and shape the 3D terrain in the target area 40
To do.

Also, the cloud placement unit 314 refers to the cloud distribution map data 430, and places a cloud (cloud object 31) at a predetermined altitude above the target area 40 set by the target area setting unit 312 (step S31). S4).

When a three-dimensional landform is formed in the target area 40 and a cloud is arranged, the image generator 320 then selects the viewpoint F based on the set position and orientation of the viewpoint F.
An image in the game space viewed from the viewpoint is generated (step S
5). At this time, the cloud shadow reflection unit 321 executes the cloud shadow expression process according to the cloud shadow reflection program 420. Specifically, the cloud shadow reflection unit 321 specifies the cloud texture 50 in the range corresponding to the target region 40, that is, as shown in FIG. At the same time, the RGB value of the corresponding terrain texture and the RGB value representing the cloud shadow, that is, (0, 0, 0) representing 'black' are expressed based on the α value set in the cloud texture 50. By combining (for example, α blending), the three-dimensional landform formed in the target region 40 is colored. On the other hand, the image generation unit 320 represents an RGB value representing a cloud, that is, “white” in the cloud texture 50 specified by the cloud shadow reflection unit 321 (255, 255, 25).
By giving 5), the cloud object 31 arranged above the target area 40 is colored.

Thereafter, the processing unit 300 performs the image generation unit 32.
The game image generated by 0 is displayed on the display unit 200. When the game image for one frame is displayed by performing the above processing, the processing unit 300 ends this processing.

Next, an example of a hardware configuration capable of realizing the game apparatus will be described with reference to FIG. In the apparatus shown in the figure, CPU 1000, ROM 1002, R
AM 1004, information storage medium 1006, sound generation IC 10
08, image generation IC 1010, I / O port 1012,
1014 are connected to each other via a system bus 1016 so as to be able to input and output data. And image generation IC1
A display device 1018 is connected to 010 and a sound generation IC 1
A speaker 1020 is connected to 008 and a control device 1022 is connected to the I / O port 1012.
A communication device 1024 is connected to the / O port 1014.

The information storage medium 1006 mainly stores a program, image data for representing a display object, sound data, play data, and the like. The storage unit 4 in FIG.
It is equivalent to 00. For example, a home game device
In FIG. 1, a CD-ROM, game cassette, DVD, or the like is used as the information storage medium 1006 for storing the game program 410 or the like, and a memory card or the like is used as the information storage medium 1006 for storing the character DB. In a personal computer, CD-RO
M, DVD, hard disk, etc. are used. Also,
The arcade game device uses a hard disk such as a ROM. In this case, the information storage medium 1006 is a ROM.
1002.

The control device 1022 corresponds to a game controller, an operation panel, and the like, and is a device for inputting the result of determination made by the user in accordance with the progress of the game to the apparatus main body. This control device 1022
Corresponds to the operation unit 100 of FIG.

In accordance with the program and data stored in the information storage medium 1006, the system program stored in the ROM 1002 (initialization information of the apparatus main body, etc.), the signal input by the control device 1022, etc., the CPU
1000 performs control of the entire apparatus and various data processing.
The RAM 1004 is a storage means used as a work area of the CPU 1000, and temporarily stores image data and play data for one frame, given contents of the information storage medium 1006 and ROM 1002, or CP
The calculation result of U1000 is stored.

Furthermore, this type of device includes a sound generation IC 100.
8 and an image generation IC 1010 are provided so that game sounds and game images can be suitably output. The sound generation IC 1008 is an information storage medium 1006 or R
This is an integrated circuit that generates game sounds such as sound effects and background sounds based on information stored in the OM 1002, and the generated game sounds are output by a speaker 1020. Further, the image generation IC 1010 includes a RAM 10
04, an integrated circuit that generates pixel information to be output to the display device 1018 based on image information sent from the ROM 1002, the information storage medium 1006, and the like. The display device 1018 is realized by a CRT, LCD, TV, plasma display, projector, or the like, and corresponds to the display unit 200 in FIG.

The communication device 1024 exchanges various information used inside the game device to the outside. The communication device 1024 is connected to other game devices and connected to the game program 41.
It is used for sending / receiving given information corresponding to 0, sending / receiving information about the game program 410, etc. via a given communication line.

Note that the image generation IC 1010 and the sound generation IC 1
The processing performed in 008 or the like may be performed in software by the CPU 1000 or a general-purpose DSP. In this case, the CPU 1000 corresponds to the processing unit 300.

Further, in the present embodiment, the present invention is
We explained the case where it was applied to a home game device.
Of course, the present invention can also be applied to an arcade game device, a portable game device, a personal computer, a portable terminal (including a mobile phone), a kiosk terminal, and the like.

Note that the present invention is not limited to the contents of the above-described embodiment, and can be appropriately changed without departing from the gist of the present invention.

For example, when mapping the cloud texture 50 to the three-dimensional terrain formed in the target area 40, the resolution of the cloud shadow texture 50 is increased by using the interpolation function of bilinear filtering.
The number of texels constituting the cloud texture 50 can also be increased.

Bilinear filtering will be described. FIG. 15A shows existing pixels (E1, E2, E
3 and E4) and a pixel (D) interpolated by bilinear filtering. FIG.
As shown in (a), the color CD of the pixel (sampling point) D to be interpolated is a color obtained by interpolating the colors of the pixels E1 to E4 around D. Specifically, based on the coordinates of E1 to E4 and the coordinates of D, the coordinate ratio β: 1-β (0 ≦ β in the x-axis direction)
≦ 1) and the coordinate ratio γ in the y-axis direction: 1−γ (0 ≦ γ ≦ 1)
And ask. The D color CD (output color by bilinear filtering) is expressed by the following equation. CD = (1−β) × (1−γ) × CE1 + β × (1−γ) × CE2 + (1−β) × γ × CE3 + β × γ × CE4 (1)

Further, as shown in FIG. 15B, β = γ
== 1/2, the color CD of the pixel D to be interpolated
Is as follows. CD = (CE1 + CE2 + CE3 + CE4) / 4 (2) Therefore, by using the above equation (2), the resolution of the cloud texture 50 mapped to the three-dimensional terrain is increased.
That is, the number of texels is increased.

For example, from a cloud texture 50 (see FIG. 10) composed of 64 × 64 texels, 256 × 25.
A cloud shadow texture composed of 6 texels is generated. That is, the number of texels T arranged in the vertical direction (M direction) and the horizontal direction (N direction) increases by 4 (= 256/64) times, respectively. Therefore, 16 (= 4 × 4) for one lattice R
Each texel T corresponds.

Also, the texel T to be inserted (increased)
Is determined by weighted averaging the colors of the surrounding texels T based on the above equation (2). As a result,
The edge of the cloud shadow can be blurred, and an effect that a more realistic expression of the cloud shadow can be realized can be obtained.

It should be noted that in an image generating apparatus such as a game apparatus, interpolated pixel data calculation processing such as nearest neighbor interpolation, bilinear interpolation (bilinear filtering), and cubic convolution interpolation (trilinear filtering). May be realized as a hardware function. In such a case, the above process can be easily realized by using this function.

In this embodiment, the cloud shadow is expressed by parallelly projecting the cloud distribution map 30 in the vertical direction (Y-axis direction) on the topographic map (projection direction A in FIG. 16). However, the projection direction is not limited to the vertical direction and may be projected from another direction.

Specifically, the cloud distribution map 30 may be projected from the projection direction B shown in FIG. However, as shown in FIG. 16, the cloud texture 50 described above is used.
A cloud shadow of a cloud different from the cloud represented by is represented in the target area 40. Therefore, the projection direction B
And the range (cloud) of the cloud distribution map reflected in the target area 40 in accordance with the angle θ formed by the ground plane (XZ plane) or the height (elevation) Y _h on the topographic map 20 where the clouds are arranged. Change the texture 50). This allows, for example,
More realistic cloud shadows can be expressed in the morning sun and sunset.

Further, the present invention can be applied to, for example, a soccer game to express the shadows of players on the field.

At that time, the field is the topographic map 20.
In addition, a distribution map indicating the positions of players in the field (for example, the positions of a total of 22 players in the case of a soccer game) corresponds to the cloud distribution map 30.

In the distribution chart, the shadow of the player is shown at a position corresponding to the position on the field of each player. This will be described more specifically. Each player is represented by a polygon model in a model coordinate system, as in the conventional method, and is arranged in the world coordinate system, which is a game space, by performing coordinate conversion from this model coordinate system. Then, the shadow model of the player is obtained by projecting the polygon model in the model coordinate system from a given direction. In the past, this shadow texture was α-synthesized in the game space, but here it is mapped onto the distribution map. On this occasion,
α synthesis is not performed. That is, the shadow texture is overwritten on the distribution map.

Then, after mapping the shadow texture of all the players on the distribution map, the distribution map is mapped to the field. As a result, multiple players crossed,
Even when shadows overlap, it is possible to avoid a contradiction such that the overlapped portion is expressed darkly.

When expressing a game of night game, since a plurality of light sources are set, a plurality of shadows corresponding to each light source may be generated and mapped on the distribution map. In addition, this method can be applied not only to the player but also to a ball or the like, and of course, it may be applied to any other object.

[0124]

According to the present invention, a cloud shadow is represented on the terrain by projecting the cloud distribution map 30 indicating the cloud distribution onto the terrain map 20 in parallel. That is, it is possible to easily realize the expression of cloud shadows regardless of whether the terrain is raised, depressed, or inclined. Furthermore, by arranging clouds on the topographic map 20 based on the cloud distribution map 30, it is possible to realize cloud shadow expression that directly reflects the shape of the arranged clouds. Further, unlike a method in which a plurality of cloud objects are arranged on the terrain and each of the cloud objects is shaded, shadowing is performed once based on the cloud distribution map 30 indicating the cloud distribution of the entire terrain map 20. Therefore, it is possible to avoid the contradiction that the shadow overlap portion becomes dark.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a game device to which the present invention is applied.

FIG. 2 is a schematic diagram showing the relationship between topography and clouds.

FIG. 3 is a diagram illustrating a state in which a target area is set in a terrain map.

FIG. 4 is a diagram illustrating an example of topography expressed three-dimensionally.

FIG. 5 is a diagram showing an example of a topographic map.

FIG. 6 is a diagram illustrating an example of topographic data.

FIG. 7 is a diagram showing an example of a cloud distribution map.

FIG. 8 is a diagram illustrating determination of an area center based on a viewpoint.

FIG. 9 is a diagram illustrating an example of a target area.

FIG. 10 is a diagram illustrating an example of a cloud shadow texture.

FIG. 11 is a diagram illustrating an example of a game image.

FIG. 12 is a diagram illustrating an example of functional blocks.

FIG. 13 is a flowchart illustrating an example of cloud shadow expression processing.

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

FIG. 15 is a diagram illustrating bilinear filtering.

FIG. 16 is a diagram for explaining a change in the range of a cloud distribution map to be employed.

[Explanation of symbols]

10 Game device 100 operation unit 200 display section 300 processor 310 Game calculation part 311 Viewpoint setting section 312 Target area setting section 313 Terrain Formation Department 314 Cloud placement part 320 Image generator 321 Cloud shadow reflection part 400 storage unit 410 Game program 411 Cloud Shadow Expression Program 420 Terrain data 430 Cloud distribution map 20 Terrain map 30 Cloud distribution map 31 Cloud object 40 Target area 50 cloud texture

Claims (17)

(57) [Claims] 1. A program for causing a computer to generate a virtual space image based on a given viewpoint and execute a given game, wherein the program is a topographical area and / or a sky above the virtual space. Generating means for generating plane information representing the distribution of a given object placed in the plane, and reflecting the distribution of the given object represented by the plane information on the terrain area; A program for causing the computer to function as reflecting means for reflecting the shadow of the given object in the terrain area according to the distribution of the object. 2. A program for causing a computer to generate a virtual space image based on a given viewpoint and execute a given game, the program being arranged above the terrain area set in the virtual space. Generating means for generating plane information representing the distribution of a given object; and reflecting means for reflecting a shadow according to the distribution of the given object in the terrain area based on the plane information. A program to make it work. 3. The program according to claim 1, wherein the reflecting means projects the distribution of the given object represented by the plane information onto the terrain area in parallel. A program for causing a shadow of a given object to function in the terrain area. 4. The program according to claim 1, wherein the given object is a cloud-like object, and a cloud-like shape is formed above the topographic area based on the plane information. A program for causing the computer to further function as arrangement means for arranging objects. 5. A program for causing a computer to generate a virtual space image based on a given viewpoint and execute a given game, the program being arranged above the terrain area set in the virtual space. Generating means for generating plane information representing a distribution of a given object that is a cloud-like object, reflecting means for reflecting a shadow of the given object in the terrain area based on the plane information, A program for causing the computer to function as arrangement means for arranging a cloud-like object in the sky above the terrain area based on plane information. 6. The program according to claim 2, wherein said computer is further functioned as means for dividing a given two-dimensional plane of said topographic area into unit areas, A generating unit that causes the computer to generate the plane information including at least information indicating whether or not the given object exists above the topographic area corresponding to each unit area; A program for causing the computer to function so that a shadow of the given object is reflected on a terrain area corresponding to the unit area for each unit area. 7. The program according to claim 2, wherein a two-dimensional grid having height information of each grid point is assigned to a given two-dimensional plane of the topographic area. The computer further functions as terrain forming means for forming the terrain in the terrain area by connecting the coordinates of each grid point assigned to the terrain area in the two-dimensional grid, and the generating means The computer functions to generate the plane information including at least information indicating the presence or absence of the given object above the topographic region corresponding to each grid of the two-dimensional grid, For each grid of the two-dimensional grid, a reflecting means for causing the computer to function so as to reflect the shadow of the given object on the terrain area corresponding to the grid. Program. 8. The program according to claim 1, wherein the reflecting means reflects a position on the terrain area where the shadow of the given object is reflected by a given light source. A program for causing the computer to function based on the determination. 9. The program according to any one of claims 1 to 8.
Readable information storage by computer storing ram
Medium. 10. Generate a virtual space image based on a given viewpoint.
A game system for running a given game
There are, on the terrain area is set in the virtual space and / or in the sky
Plane information representing the distribution of the given object being placed
Generating means for generating the given object represented by the plane information
By reflecting the distribution of
The given object according to the distribution of the given object
Reflecting means for reflecting the shadow of the project to the terrain area . 11. Generate a virtual space image based on a given viewpoint.
A game system for running a given game
There is disposed over the terrain area set in the virtual space
Generate plane information representing the distribution of a given object
Based on the generation means and the plane information, the distribution of the given object
Reflecting means for reflecting a shadow according to a cloth on the terrain area . 12. A game system according to claim 10 or 11.
The reflecting means is represented by the plane information.
Parallel projection of the distribution of a given object onto the terrain area
The shadow of the given object
A game system that is reflected in the area. 13. The method according to any one of claims 10 to 12.
In the game system, the given object is a cloud-like object, and a cloud-like object is formed above the terrain area based on the plane information.
Further comprising an arrangement means for arranging the object
A game system. 14. Generate a virtual space image based on a given viewpoint.
A game system for running a given game
There is disposed over the terrain area set in the virtual space
Show the distribution of a given object that is a cloud object
Generating means for generating the plane information, and a shadow of the given object based on the plane information.
Reflecting means for reflecting the terrain area to the topography area, and based on the plane information,
A game system comprising: arrangement means for arranging objects . 15. The method according to any one of claims 11 to 14.
A game system that divides a given two-dimensional plane of the terrain area into unit areas.
And the generating means includes at least each of the plane information in the plane information.
Above the topographic area corresponding to the unit area,
Information including the presence / absence of a given object is generated, and the reflection unit applies the unit area to each unit area.
Reflect the shadow of the given object on the corresponding terrain area
A game system characterized by that. 16. The method according to any one of claims 11 to 14.
A game system, wherein the height information of each grid point is given to a given two-dimensional plane of the terrain area.
Assigning means for assigning a two-dimensional grid having information, and each of the two-dimensional grids assigned to the topographic area
By connecting the coordinates of the grid points,
Terrain forming means for forming the plane information, and the generating means includes at least the second information in the plane information.
In the sky above the terrain area corresponding to each grid of the dimensional grid
Including information indicating the presence or absence of the given object.
And the reflecting means generates the case for each lattice of the two-dimensional lattice.
Shadow of the given object on the terrain area corresponding to the child
A game system characterized by reflecting. 17. The method according to any one of claims 10 to 16.
In the game system, the reflecting means reflects a shadow of the given object.
Position on the terrain area to be determined based on a given light source
A game system characterized by