JP3777288B2 - GAME SYSTEM AND INFORMATION STORAGE MEDIUM - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a game system and an information storage medium.
[0002]
[Background Art and Problems to be Solved by the Invention]
Conventionally, a game system that generates an image that can be seen from a given viewpoint in an object space that is a virtual three-dimensional space is known, and is popular as a device that can experience so-called virtual reality. Taking a game system that can enjoy a role-playing game as an example, a player operates a character (object) and moves it on a map in the object space to play against enemy characters or interact with other characters. Or enjoy the game by visiting various towns.
[0003]
In such a game system, an object representing a character or the like is usually composed of a plurality of polygons (primitive surfaces). Then, an object (model) composed of the polygons is arranged in the object space, and geometry processing (three-dimensional calculation) is performed to generate an image that can be seen from the virtual camera (viewpoint). Thereby, even when this object is viewed from various directions by the virtual camera, it is possible to generate a consistent game image.
[0004]
However, the game image generated in this way is a mathematically correct image, but there is a problem that it cannot be appealed to the player's feelings.
[0005]
For example, consider a case where a character appearing in an animation or manga is represented by an object. In such a case, shading the object by Gouraud shading or phone shading can obtain a realistic image, but it has a different atmosphere from that familiar to ordinary people in anime and manga. An image is generated.
[0006]
The present invention has been made in view of the problems as described above, and the object of the present invention is to provide a game system and information capable of optimal shading for objects representing characters and the like appearing in anime and manga It is to provide a storage medium.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a game system that performs image generation, and includes mask information for specifying a shadow region in which a shadow expression image is to be drawn based on object information and light source information. Means for generating, and means for drawing a shadow expression image in a shadow area of the object based on the generated mask information. The information storage medium according to the present invention is an information storage medium that can be used by a computer, and includes a program for executing the above means. The program according to the present invention is a program (including a program embodied in a carrier wave) that can be used by a computer, and includes a processing routine for executing the above means.
[0008]
According to the present invention, object information (for example, a normal vector representing the direction of each surface of the object, an object position in the frame, rotation angle data, etc.) and light source information (for example, a light source vector or a light source position) are included. Based on this, mask information (for example, α plane) for specifying the shadow area is generated. Then, a shadow expression image is drawn in the shadow area based on the mask information.
[0009]
Therefore, according to the present invention, it is possible to draw a two-dimensional shadow expression image on a three-dimensional object composed of primitive surfaces, and an object representing a character or the like appearing in an animation or a manga. The most suitable shading is possible.
[0010]
Further, according to the present invention, since the shadow area is specified by the object information and the light source information, when the position or direction of the object or the light source changes, the position or shape of the shadow area also changes in real time accordingly. Become. Therefore, while the position and shape of the shadow area change like a shadow area obtained by a shadow process such as normal Gouraud shading or von shading, only the shadow expression image drawn in the shadow area is two-dimensional. It becomes possible to make a realistic picture.
[0011]
The game system, the information storage medium, and the program according to the present invention also perform a mask composition of an original image of an object and a shadow expression image of the object based on the generated mask information, so that the shadow expression image is generated in the shadow area. An image of a drawn object is generated. The mask composition in this case is, for example, setting an α value for each pixel in the drawing area and determining whether to draw an original image or a shadow expression image on the pixel based on the α value. Can be realized.
[0012]
In addition, the game system, information storage medium, and program according to the present invention draw a primitive surface having a shape including at least the original image of the object drawn in the drawing area in the drawing area while mapping the texture of the shadow expression image. Thus, a shadow expression image is drawn in the shadow area. In this way, the shadow expression image can be drawn in the shadow area with a simple process of mapping the texture of the shadow expression image onto the primitive surface, and the processing load can be reduced. Also, by simply replacing the texture of the shadow expression image, various shadow expression images can be drawn in the shadow area, and the variety of generated images can be increased.
[0013]
The primitive surface in this case may be a screen-sized primitive surface, or may be a primitive surface generated based on the shape data of an object or a simple object that includes the object.
[0014]
The game system, information storage medium, and program according to the present invention obtain texture coordinates for designating a mask generation texture based on object information and light source information, and generate a mask based on the obtained texture coordinates. The mask information is generated by mapping a texture to an object. In this way, mask information can be generated by a simple process of simply mapping a mask generating texture to an object, and the processing load can be reduced.
[0015]
In the game system, information storage medium, and program according to the present invention, the mask generating texture has an α value different from the first texture pattern and an α value set in each texel of the first texture pattern. A second texture pattern set for each texel, and when the texture coordinates for designating the mask generation texture are between a first value and a second value, When a texture pattern is specified and the texture coordinates are between a second value and a third value, the second texture pattern is specified. In this way, it becomes possible to control the range of the shaded area simply by changing the second value, and the variety of the generated image can be increased.
[0016]
In addition, the game system, information storage medium, and program according to the present invention draw the image of the background texture and the mask generation by overlapping the object to which the background texture is mapped and the object to which the mask generation texture is mapped. It is characterized in that the α value of the texture is set for each pixel in the drawing area. In this way, using the α value set for each pixel in the drawing area as mask information, the original image (the image of the object to which the background texture is mapped) and the shadow expression image can be mask-synthesized. .
[0017]
When drawing an object to which the texture for mask generation is mapped in the drawing area, drawing data (for example, polygon data after perspective transformation) obtained by performing geometry processing on the object to which the background texture is mapped is used. It is desirable to reuse. In this way, it is possible to omit the geometry processing for the object to which the mask generating texture is mapped, and the processing load can be reduced.
[0018]
The present invention is also a game system for generating an image, wherein a shadow expression image should be drawn in a drawing area in which a two-dimensional original image of an object is drawn and means for drawing the original image of the object in the drawing area Means for specifying a shadow area based on object information and light source information, and rendering a two-dimensional shadow expression image of the object in the specified shadow area. The information storage medium according to the present invention is an information storage medium that can be used by a computer, and includes a program for executing the above means. The program according to the present invention is a program (including a program embodied in a carrier wave) that can be used by a computer, and includes a processing routine for executing the above means.
[0019]
According to the present invention, a two-dimensional shadow expression image is drawn in a shadow area specified by object information and light source information. Therefore, the object and the background are parsed based on the geometry processing, while the shadow display image drawn in the shadow area is not parsed. Therefore, it is possible to apply a two-dimensional shadow in the screen tone style that ordinary people are accustomed to in anime and manga to objects, and it is possible to optimally shade objects that represent characters appearing in anime and manga. .
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
[0021]
1. Constitution
FIG. 1 shows an example of a block diagram of the game system (image generation system) of this embodiment. In this figure, the present embodiment only needs to include at least the processing unit 100 (or include the processing unit 100 and the storage unit 170), and the other blocks can be optional components.
[0022]
The operation unit 160 is for a player to input operation data, and the function can be realized by hardware such as a lever, a button, a microphone, or a housing.
[0023]
The storage unit 170 serves as a work area such as the processing unit 100 or the communication unit 196, and its function can be realized by hardware such as a RAM.
[0024]
An information storage medium (storage medium usable by a computer) 180 stores information such as programs and data, and functions thereof are an optical disk (CD, DVD), a magneto-optical disk (MO), a magnetic disk, and a hard disk. It can be realized by hardware such as a magnetic tape or a memory (ROM). The processing unit 100 performs various processes of the present invention (this embodiment) based on information stored in the information storage medium 180. That is, the information storage medium 180 stores information (program or data) for executing the means of the present invention (this embodiment) (particularly, the blocks included in the processing unit 100).
[0025]
Part or all of the information stored in the information storage medium 180 is transferred to the storage unit 170 when the system is powered on. The information storage medium 180 also includes a program for performing the processing of the present invention, image data, sound data, shape data of the display object, information for instructing the processing of the present invention, or processing in accordance with the instructions. Information etc. can be included.
[0026]
The display unit 190 outputs an image generated according to the present embodiment, and the function thereof can be realized by hardware such as a CRT, LCD, or HMD (head mounted display).
[0027]
The sound output unit 192 outputs the sound generated by the present embodiment, and its function can be realized by hardware such as a speaker.
[0028]
The portable information storage device 194 stores player personal data, game save data, and the like. As the portable information storage device 194, a memory card, a portable game device, and the like can be considered.
[0029]
The communication unit 196 performs various controls for communicating with the outside (for example, a host device or other game system), and functions thereof are various processors, hardware such as a communication ASIC, It can be realized by a program.
[0030]
The program or data for executing the means of the present invention (this embodiment) may be 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. Good. Use of such an information storage medium of the host device (server) is also included in the scope of the present invention.
[0031]
The processing unit 100 (processor) performs various processes such as a game process, an image generation process, and a sound generation process based on operation data from the operation unit 160, a program, and the like. The functions of the processing unit 100 can be realized by hardware such as various processors (CPU, DSP, etc.) or ASIC (gate array, etc.) and a given program (game program).
[0032]
Here, game processing performed by the processing unit 100 includes coin (price) acceptance processing, various mode setting processing, game progress processing, selection screen setting processing, position of an object (one or more primitive surfaces), Processing for obtaining a rotation angle (rotation angle about X, Y or Z axis), processing for moving an object (motion processing), processing for obtaining a viewpoint position (virtual camera position) and a line-of-sight angle (virtual camera rotation angle), Processing to place objects such as map objects in the object space, hit check processing, processing to calculate game results (results, results), processing for multiple players to play in a common game space, game over processing, etc. Can think.
[0033]
Further, the processing unit 100 generates an image that can be seen from a given viewpoint (virtual camera) in the object space, for example, based on the game processing result, and outputs the image to the display unit 190.
[0034]
Further, the processing unit 100 performs various kinds of sound processing based on the above-described game processing result, generates a sound such as BGM, sound effect, or sound, and outputs the sound to the sound output unit 192.
[0035]
Note that all of the functions of the processing unit 100 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.
[0036]
The processing unit 100 includes a geometry processing unit 110, an original image drawing unit 120, a mask information generation unit 122, and a shadow drawing unit 124.
[0037]
The geometry processing unit 110 performs various types of geometry processing (three-dimensional calculation) such as coordinate transformation, clipping processing, perspective transformation, or light source calculation on an object. The drawing data (position coordinates, texture coordinates, color (luminance) data, normal vector or α value, etc. given to the vertices) obtained by the geometry processing is stored in the main storage unit 172 of the storage unit 170 and saved. Is done.
[0038]
The original image drawing unit 120 performs processing for drawing an original image (background image) of an object in a drawing area 176 (a frame buffer, a temporary frame buffer, etc.). More specifically, the object is drawn in the drawing area 176 while mapping the background texture stored in the texture storage unit 174 to the object.
[0039]
Based on the object information (normal vector representing the direction of each surface of the object, object position, rotation angle data) and light source information (light source vector, light source position, etc.) Mask information for specifying a region to be drawn (screen tone or the like) is generated. More specifically, the texture coordinate calculation unit 112 included in the geometry processing unit 110 determines texture coordinates for designating the mask generation texture stored in the texture storage unit 174 based on the object information and the light source information. Ask. Then, the mask information is generated by mapping the mask generation texture to the object based on the obtained texture coordinates. That is, by drawing an object to which the mask generating texture is mapped in the drawing area 176, an α value plane functioning as mask information is set in each pixel of the drawing area 176.
[0040]
The α value (A value) is information stored in association with each pixel, for example, plus alpha information other than color information. The α value can also be used as transparency (equivalent to opacity and translucency) and bump information, but in the present embodiment, this α value is used as mask information.
[0041]
The shadow drawing unit 124 performs a process of drawing a shadow expression image in the shadow region of the object based on the mask information generated by the mask information generation unit 122. More specifically, the shadow expression image is drawn in the shadow area by performing mask composition on the original image (background image) of the object and the shadow expression image of the object based on the mask information. This makes it possible to generate an image of an object that looks as if a screen tone has been applied.
[0042]
Note that the game system according to the present embodiment may be a system dedicated to the single player mode in which only one player can play, and not only such a single player mode but also a multiplayer mode in which a plurality of players can play. A system may be provided.
[0043]
Further, when a plurality of players play, game images and game sounds to be provided to the plurality of players may be generated using one terminal, or connected via a network (transmission line, communication line) or the like. Alternatively, it may be generated using a plurality of terminals.
[0044]
2. Features of this embodiment
2.1 Drawing shadow expression images
Now, in the world of comics and animation, what is called a screen tone is widely used in order to save the labor of drawing a fine pattern. This screen tone is a transparent vinyl having various patterns printed on the front surface and a glue bonded to the back surface by pressure bonding. For example, when expressing the shadow of a cartoon character, the work of drawing the shadow of the cartoon character can be saved by cutting out and pasting a screen tone representing the shadow in a desired shape.
[0045]
On the other hand, in the world of 3D games, shading processes such as Gouraud shading and phone shading are widely used in order to give realistic shading to objects such as characters.
[0046]
However, by shading objects that express comic characters by using such Gouraud shading or phone shading, an image with a completely different atmosphere from that which ordinary people are accustomed to using comics is generated. End up.
[0047]
Therefore, an important issue is how to apply a comical shading represented by a screen tone to an object composed of primitive surfaces such as polygons and free-form surfaces.
[0048]
In order to solve such a problem, in the present embodiment, as shown in FIG. 2, first, based on the information on the object OB (for example, the vertex normal vector) and the information on the light source LS (for example, the light source vector LSV), Mask information for specifying a shadow area in which a shadow expression image (screen tone) is to be drawn is generated. The light source may be a parallel light source or a point light source.
[0049]
FIG. 3A shows an example of mask information generated on the frame buffer (drawing area in a broad sense). In the present embodiment, an α value is used as mask information. In FIG. 3A, a region where α = 0.0 is a shadow region (non-mask region), and a region where α = 1.0 is a non-shadow region (mask region).
[0050]
Note that the method of setting the α value is arbitrary, and it is sufficient that at least the α value is different between the shadow region and the non-shadow region.
[0051]
In this embodiment, by performing mask composition based on the mask information generated as shown in FIG. 3A, as shown in FIG. 3B, a shadow expression image ( In the figure, an image of the object OB on which a screen stripe of a vertical stripe pattern) is drawn is generated.
[0052]
More specifically, an original image of the object OB shown in FIG. 4A (an OB image on which the background texture is mapped) and a shadow expression image (vertical stripe pattern) shown in FIG. By combining the mask using the mask information (α plane) shown in FIG. 3 (A), the image of the object OB having the screen tone-like shading shown in FIG. 3 (B) was successfully generated. Yes.
[0053]
As described above, according to the present embodiment, an object that appears as if a screen tone has been applied to a shaded area, even though the object is composed of primitive surfaces such as polygons, free-form surfaces, and subdivision surfaces. Images can be generated. Accordingly, it is possible to generate a game image that can express a so-called anime-style image and appeal to the feelings of ordinary people who love anime and manga.
[0054]
In other words, when general Gouraud shading or phone shading is used, the shading is subject to gradation, so the boundary between the shadow area and the non-shadow area is blurred. Therefore, although it is real, an image having an atmosphere different from that of an animation image familiar to ordinary people is generated.
[0055]
On the other hand, according to the present embodiment, as shown in FIG. 3B, the boundary between the shadow area and the non-shadow area is clearly distinguished without blurring, so that it appears as if a shaded screen tone is applied. An anime-like image that looks like this can be generated.
[0056]
According to the present embodiment, since a two-dimensional shadow expression image is drawn in the shadow area, the shadow expression image is not parsed. Taking FIG. 3B as an example, equally-spaced vertical stripe patterns are drawn in the shadow area without distortion. Therefore, it is possible to generate an image that looks as if a two-dimensional screen tone is pasted on an object expressed in three dimensions.
[0057]
In addition, according to the present embodiment, by replacing the shadow expression image to be combined with the mask, it is possible to express an image of an object with a different screen tone. For example, FIG. 5 shows an image generated when the vertical stripe pattern shadow expression image of FIG. 4B is replaced with a dot pattern shadow expression image. As described above, according to the present embodiment, the variety degree of the generated image can be remarkably increased by a simple operation of replacing the shadow expression image to be used.
[0058]
According to the present embodiment, the shadow area is specified by the object information and the light source information. Therefore, as shown in FIG. 6, when the direction of the light source vector (light source position) changes or the position or direction of the object OB changes, the position and shape of the shadow area also change in real time accordingly. Therefore, it is possible to make only the shadow expression image drawn in the shadow area into a two-dimensional picture such as a screen tone while taking advantage of the advantage obtained by using the object of the three-dimensional expression as it is.
[0059]
Note that the drawing of the shadow expression image in the shadow area can be realized by the following method.
[0060]
That is, as shown in FIG. 7, for example, a screen-sized polygon 12 (primitive surface) to which a texture 10 (vertical stripe pattern, dot pattern, etc.) of a shadow expression image is mapped is displayed on a frame buffer ( Draw in the drawing area. In this case, an α value (mask information) as shown in FIG. 3A is written in each pixel of the frame buffer. Accordingly, an image as shown in FIG. 3B can be generated by drawing the screen size polygon 12 to which the texture 10 is mapped in the frame buffer while performing the disnation α test using this α value. For example, the drawing of the screen size polygon 12 (shadow expression image) is permitted for the pixels with α <1.0, and the shading is disabled for the pixels with α = 1.0. A shadow expression image can be drawn only in the area.
[0061]
From the viewpoint of reducing the processing load, the polygon to be mapped with the texture 10 does not necessarily have to be a screen-sized polygon. For example, as shown in FIG. 8, a polygon that contains at least the object OB. 14 (primitive surface) may be used. The smaller the size of the polygon 14 is, the more the burden of drawing processing can be reduced.
[0062]
In this case, the polygon 14 shown in FIG. 8 may be generated based on the maximum and minimum values of the X and Y coordinates after perspective transformation of each vertex of the object OB, or a simple object (including the object OB) ( It may be generated based on the maximum and minimum values of the X and Y coordinates after the perspective transformation of the vertex of the bounding volume.
[0063]
2.2 Generation of mask information by texture mapping
In the present embodiment, mask information as shown in FIG. 3A is generated using texture mapping. More specifically, the mask information is generated by obtaining the texture coordinates of the mask generating texture based on the object information and the light source information, and mapping the mask generating texture to the object based on the obtained texture coordinates. is doing.
[0064]
For example, as shown in FIG. 9, when the object OB is composed of a plurality of polygons, the position coordinates (X, Y, Z), color (luminance) data (R) are included in the vertices VX1 to VX6 of the object OB. , G, B), texture coordinates (U, V), normal vectors (NX, NY, NZ), α values, and the like are set.
[0065]
Here, the position coordinates (X, Y, Z) are data for specifying the shape of the OB, and the color data (R, G, B) are data for determining the color and shading of the OB. The texture coordinates (U, V) are data for designating a texture to be mapped to OB. The normal vector (NX, NY, NZ) is data used for light source calculation using the light source LS (light source vector LSV).
[0066]
In the present embodiment, normal vectors N1 to N6 (object information in a broad sense) set at the respective vertices VX1 to VX6 of the object OB and a vector LSVI (light source in a broad sense) pointing in the opposite direction with respect to the light source vector LSV. Information) and the inner product value IP. Then, based on this IP, a calculation like the following formula (1) is performed to obtain the texture coordinate V.
[0067]
V = (IP + 1) / 2 (1)
Since the range of the inner product value IP is −1.0 ≦ IP ≦ 1.0, the range of the texture coordinate V is normalized to 0.0 ≦ V ≦ 1.0 by the above equation (1). .
[0068]
By obtaining the texture coordinates V as described above, the texture coordinates V of the vertices VX1 to VX6 in FIG. 9 are 0.1, 0.5, 0.75, 1.0, 0.7, 0, respectively. .25. On the other hand, the texture coordinate U is fixed to 0.0.
[0069]
In this embodiment, a texture as shown in FIG. 10 is prepared as a mask generation texture specified by the texture coordinates U and V obtained as described above.
[0070]
The mask generating texture has a first texture pattern in which the texel α value is set to 0.0, and a second texture pattern in which the texel α value is set to 1.0. (It is optional for image data such as color data other than the α value). Note that the α values set in the texels of the first and second texture patterns need only be different from each other, and are not limited to the settings shown in FIG.
[0071]
In the texture for mask generation in FIG. 10, when the texture coordinates V are 0.0 ≦ V ≦ 0.4 (0.0 is the first value and 0.4 is the second value), the texel α The first texture pattern whose value is set to 0.0 is designated. On the other hand, when the texture coordinate V is 0.4 <V ≦ 1.0 (1.0 is the third value), the second texture pattern in which the α value of the texel is set to 1.0 Will be specified.
[0072]
Here, the first texture pattern corresponds to a shadow portion (non-mask portion), and the second texture pattern corresponds to a non-shadow portion (mask portion). Accordingly, in FIG. 9, the thick line portion 20 where the texture coordinate V is 0.0 ≦ V ≦ 0.4 becomes a shaded portion.
[0073]
That is, in the thick line portion 20 in FIG. 9 which is a shadow portion, the α value of the texel is set to 0.0, so that the shadow expression image in FIG. On the other hand, since the α value of the texel is set to 1.0 except for the thick line portion 20, the shadow expression image is masked by the destination α test and is not drawn in the frame buffer. As a result, an image as shown in FIG. 3B can be generated.
[0074]
As described above, if the mask information is generated by mapping the mask generation texture based on the texture coordinates obtained from the object information (normal vector) and the light source information (light source vector), FIG. The range of the shadow area can be controlled simply by changing the shape of the texture pattern. Specifically, the range of the shadow area can be narrowed or widened only by changing the position of the boundary (second value) indicated by C1 in FIG. As a result, the shaded state of the object can be variously changed with a simple process, and the variety of the generated image can be increased.
[0075]
3. Processing of this embodiment
Next, a detailed example of the processing of the present embodiment will be described using the flowchart of FIG.
[0076]
First, a background object drawing process is performed (step S1).
[0077]
That is, the object is drawn in the frame buffer while mapping the background texture to the object (step S2). As a result, an original image as shown in FIG.
[0078]
Next, a mask object drawing process is performed (step S2).
[0079]
That is, as described with reference to FIG. 9, the mask generation texture of FIG. A texture coordinate V for designating is obtained (step S4). The texture coordinate U is fixed at 0.0.
[0080]
Based on the obtained texture coordinates U and V, an object to which the mask generating texture is mapped is drawn in the frame buffer, and an α value serving as mask information is set in each pixel of the frame buffer (step S5). As a result, as shown in FIG. 3A, for example, α = 0.0 is set in the shadow area (non-mask area), and α = 1.0 is set in the non-shadow area (mask area). It becomes like this.
[0081]
As described above, in the present embodiment, the image data of the background texture and the mask generation are generated by drawing the object (background object) to which the background texture is mapped and the object (mask object) to which the texture for mask generation is mapped in an overlapping manner. The α value of the texture is set for each pixel of the frame buffer (drawing area).
[0082]
Next, screen tone / polygon drawing processing is performed (step S6).
[0083]
That is, as described with reference to FIG. 7, a polygon to which a screen tone texture having an arbitrary pattern (for example, a vertical stripe pattern, a dot pattern) is mapped is drawn in the frame buffer (step S7). At this time, the destination α test is performed so that the screen tone polygon is drawn only for the pixels having an α value of less than 1.0 in each pixel of the frame buffer. By doing so, a screen tone polygon (shadow expression image) is drawn only in the shaded area where α = 0.0 in FIG. 3A, as shown in FIG. 3B. It becomes possible to generate an image that looks as if a shadow of a simple screen tone is pasted on the object OB.
[0084]
4). Hardware configuration
Next, an example of a hardware configuration capable of realizing the present embodiment will be described with reference to FIG.
[0085]
The main processor 900 operates based on a program stored in the CD 982 (information storage medium), a program transferred via the communication interface 990, or a program stored in the ROM 950 (one of information storage media). Various processes such as processing, image processing, and sound processing are executed.
[0086]
The coprocessor 902 assists the processing of the main processor 900, has a product-sum calculator and a divider capable of high-speed parallel calculation, and executes matrix calculation (vector calculation) at high speed. For example, if a physical simulation for moving or moving an object requires processing such as matrix operation, a program operating on the main processor 900 instructs (requests) the processing to the coprocessor 902. )
[0087]
The geometry processor 904 performs geometry processing such as coordinate transformation, perspective transformation, light source calculation, and curved surface generation, has a product-sum calculator and a divider capable of high-speed parallel computation, and performs matrix computation (vector computation). Run fast. For example, when processing such as coordinate transformation, perspective transformation, and light source calculation is performed, a program operating on the main processor 900 instructs the geometry processor 904 to perform the processing.
[0088]
The data decompression processor 906 performs a decoding process for decompressing the compressed image data and sound data, and a process for accelerating the decoding process of the main processor 900. As a result, 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. Note that the image data and sound data to be decoded are stored in the ROM 950 and the CD 982 or transferred from the outside via the communication interface 990.
[0089]
The drawing processor 910 executes drawing (rendering) processing of an object composed of primitive surfaces such as polygons and curved surfaces at high speed. When drawing an object, the main processor 900 uses the function of the DMA controller 970 to pass the object data to the drawing processor 910 and transfer the texture to the texture storage unit 924 if necessary. Then, the drawing processor 910 draws an 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 texture. The drawing processor 910 can also perform α blending (translucent processing), depth cueing, mip mapping, fog processing, trilinear filtering, anti-aliasing, shading processing, and the like. When an image for one frame is written in the frame buffer 922, the image is displayed on the display 912.
[0090]
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 sounds. The generated game sound is output from the speaker 932.
[0091]
Operation data from the game controller 942, save data from the memory card 944, and personal data are transferred via the serial interface 940.
[0092]
The ROM 950 stores system programs and the like. In the case of an arcade game system, the ROM 950 functions as an information storage medium, and various programs are stored in the ROM 950. A hard disk may be used instead of the ROM 950.
[0093]
The RAM 960 is used as a work area for various processors.
[0094]
The DMA controller 970 controls DMA transfer between the processor and memory (RAM, VRAM, ROM, etc.).
[0095]
The CD drive 980 drives a CD 982 (information storage medium) in which programs, image data, sound data, and the like are stored, and enables access to these programs and data.
[0096]
The communication interface 990 is an interface for transferring data to and from the outside via a network. In this case, as a network connected to the communication interface 990, a communication line (analog telephone line, ISDN), a high-speed serial bus, or the like can be considered. By using a communication line, data transfer via the Internet becomes possible. Further, by using the high-speed serial bus, data transfer with other game systems becomes possible.
[0097]
All of the means of the present invention may be executed by hardware alone, or may be executed only by a program stored in an information storage medium or a program distributed via a communication interface. Alternatively, it may be executed by both hardware and a program.
[0098]
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. Become. More specifically, the program instructs each processor 902, 904, 906, 910, 930, etc., which is hardware, and passes data if necessary. Each processor 902, 904, 906, 910, 930, etc. executes each means of the present invention based on the instruction and the passed data.
[0099]
FIG. 13A shows an example when 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 viewing the game image displayed on the display 1100. Various processors and various memories are mounted on the built-in system board (circuit board) 1106. Information (program or data) for executing each means 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.
[0100]
FIG. 13B shows an example in which this embodiment is applied to a home game system. The player enjoys the game by operating the game controllers 1202 and 1204 while viewing the game image displayed on the display 1200. In this case, the stored information is stored in the CD 1206, which is an information storage medium that is detachable from the main system, or in the memory cards 1208, 1209, and the like.
[0101]
FIG. 13C shows a host device 1300 and terminals 1304-1 to 1304-n connected to the host device 1300 via a network 1302 (a small-scale network such as a LAN or a wide area network such as the Internet). An example of applying this embodiment to a system including In this case, the stored information is stored in an information storage medium 1306 such as a magnetic disk device, a magnetic tape device, or a memory that can be controlled by the host device 1300, for example. When the terminals 1304-1 to 1304-n can generate game images and game sounds stand-alone, the host device 1300 receives a game program and the like for generating game images and game sounds from the terminal 1304-. 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, which is transmitted to the terminals 1304-1 to 1304-n and output at the terminal.
[0102]
In the case of the configuration shown in FIG. 13C, each unit of the present invention may be executed in a distributed manner between the host device (server) and the terminal. The storage information for executing each means of the present invention may be distributed and stored in the information storage medium of the host device (server) and the information storage medium of the terminal.
[0103]
The terminal connected to the network may be a home game system or an arcade game system. When connecting the arcade game system to a network, a portable information storage device capable of exchanging information with the arcade game system and exchanging information with the home game system. It is desirable to use (memory card, portable game device).
[0104]
The present invention is not limited to that described in the above embodiment, and various modifications can be made.
[0105]
For example, in the invention according to the dependent claim of the present invention, a part of the constituent features of the independent claim as the dependent can be omitted. Moreover, the principal part of the invention according to one independent claim of the present invention can be made dependent on another independent claim.
[0106]
In the present embodiment, the shadow expression image is drawn in the shadow area of the object using the mask information generated based on the object information and the light source information. However, without using such mask information, the shadow area is displayed in the shadow area. A shadow expression image may be drawn.
[0107]
That is, in the drawing area where the two-dimensional original image of the object is drawn, the shadow area where the shadow expression image is to be drawn is specified by some method based on the object information and the light source information, and the object shadow is specified in the specified shadow area. A two-dimensional shadow expression image is drawn.
[0108]
This also makes it possible to generate an animation-like image that looks as if a shaded screen tone has been applied. In addition, since a two-dimensional shadow expression image is drawn in the shadow area, the shadow expression image is not parsed, and an image that looks as if a two-dimensional screen tone is pasted on the three-dimensional object is generated. it can. In addition, if the object information or light source information changes, the position and shape of the shaded area will change in real time accordingly. Only an image can be made into a two-dimensional picture like a screen tone.
[0109]
The mask information generation method is also preferably the method described with reference to FIGS. 9 and 10, but is not limited thereto. For example, an α value may be set for each vertex of the object based on object information or light source information, and mask information may be generated based on the α value.
[0110]
Moreover, the form of the texture for mask generation is not limited to that described with reference to FIG.
[0111]
Further, the image pattern of the shadow expression image is not limited to that described in the present embodiment, and various modifications can be made.
[0112]
The drawing method of the shadow expression image is particularly preferably the method described with reference to FIGS. 7 and 8, but is not limited to this, and various modifications can be made.
[0113]
In the present embodiment, the case where the object is composed of polygons has been mainly described. However, the scope of the present invention includes the case where the object is composed of other forms of primitive surfaces such as a free-form surface and a subdivision surface. It is.
[0114]
The present invention can also be applied to various games (such as fighting games, shooting games, robot battle games, sports games, competition games, role playing games, music playing games, dance games, etc.).
[0115]
The present invention is also applicable to various game systems (image generation systems) such as a business game system, a home game system, a large attraction system in which a large number of players participate, a simulator, a multimedia terminal, and a system board for generating game images. Applicable.
[Brief description of the drawings]
FIG. 1 is an example of a block diagram of a game system according to the present embodiment.
FIG. 2 is a diagram for explaining a method of generating mask information based on object information and light source information.
FIG. 3A is a diagram for explaining mask information, and FIG. 3B is a diagram illustrating an example of an image generated according to the present embodiment.
FIGS. 4A and 4B are diagrams illustrating examples of an original image and a shadow expression image.
FIG. 5 is a diagram illustrating another example of an image generated according to the present embodiment.
FIG. 6 is a diagram illustrating another example of an image generated according to the present embodiment.
FIG. 7 is a diagram for explaining a technique for drawing a screen-sized polygon onto which a texture of a shadow expression image is mapped in a frame buffer;
FIG. 8 is a diagram showing another example of a polygon to which a texture of a shadow expression image is mapped.
FIG. 9 is a diagram for explaining a method for obtaining texture coordinates of a texture for mask generation based on an inner product value of a vertex normal vector and a light source vector.
FIG. 10 is a diagram illustrating an example of a texture for generating a mask.
FIG. 11 is a flowchart illustrating a detailed processing example 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 illustrating examples of various types of systems to which the present embodiment is applied.
[Explanation of symbols]
OB object
LS light source
LSV light source vector
10 Texture of shadow expression image
12 screen size polygon
14 Polygons that contain objects
100 processor
110 Geometry processing unit
112 Texture coordinate calculation unit
120 original image drawing unit
122 Mask information generation unit
124 Shading drawing part
160 Operation unit
170 Storage unit
172 Main memory
174 Texture storage unit
176 Drawing area (frame buffer, etc.)
180 Information storage medium
190 Display
192 sound output section
194 Portable information storage device
196 Communication Department

Claims (10)

A game system for generating images,
Means for generating mask information for identifying a shadow area in which a shadow expression image is to be drawn based on the object information and the light source information;
Based on the generated mask information, means for drawing a shadow expression image in the shadow area of the object;
Only including,
Based on the object information and the light source information, the texture coordinates for designating the mask generation texture are obtained, and the mask information is generated by mapping the mask generation texture to the object based on the obtained texture coordinates. A game system characterized by that. In claim 1,
A game characterized by generating an image of an object in which a shadow expression image is drawn in a shadow area by performing mask composition on the original image of the object and the shadow expression image of the object based on the generated mask information system. In claim 1 or 2,
It is characterized by drawing a shadow expression image in the shadow area by drawing a primitive surface with a shape that at least contains the original image of the object drawn in the drawing area in the drawing area while mapping the texture of the shadow expression image. Game system to play. In any one of Claims 1-3 ,
The mask generation texture includes a first texture pattern and a second texture pattern in which an α value different from an α value set in each texel of the first texture pattern is set in each texel. ,
When the texture coordinates for designating the mask generating texture are between the first value and the second value, the first texture pattern is designated, and the texture coordinates are designated by the second value. When the value is between 3, the game system is characterized in that the second texture pattern is designated. In any one of Claims 1-4 ,
By drawing the object to which the background texture is mapped and the object to which the mask generation texture is mapped, the image data of the background texture and the α value of the mask generation texture are set to each pixel of the drawing area. A game system characterized by An information storage medium storing a program usable by a computer,
The program is
Means for generating mask information for identifying a shadow area in which a shadow expression image is to be drawn based on the object information and the light source information;
Based on the generated mask information, as means for drawing a shadow expression image in the shadow area of the object,
Make the computer work ,
Based on the object information and the light source information, the texture coordinates for designating the mask generation texture are obtained, and the mask information is generated by mapping the mask generation texture to the object based on the obtained texture coordinates. An information storage medium characterized by the above. In claim 6 ,
Information that generates an image of an object in which a shadow expression image is drawn in a shadow area by performing mask composition on the original image of the object and the shadow expression image of the object based on the generated mask information Storage medium. In claim 6 or 7 ,
It is characterized by drawing a shadow expression image in the shadow area by drawing a primitive surface with a shape that at least contains the original image of the object drawn in the drawing area in the drawing area while mapping the texture of the shadow expression image. Information storage medium. In any one of Claims 6-8 ,
The mask generation texture includes a first texture pattern and a second texture pattern in which an α value different from an α value set in each texel of the first texture pattern is set in each texel. ,
When the texture coordinates for designating the mask generating texture are between the first value and the second value, the first texture pattern is designated, and the texture coordinates are designated by the second value. If the value is between 3, the second texture pattern is designated. In any one of Claims 6-9 ,
By drawing the object to which the background texture is mapped and the object to which the mask generation texture is mapped, the image data of the background texture and the α value of the mask generation texture are set to each pixel of the drawing area. An information storage medium characterized by the above.

Images