JP2013084155A - Image processing method, image processing program, image processing device, and image processing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing method, an image processing program, an image processing device, and an image processing system capable of realizing display of a 3D image having excellent appearance.SOLUTION: In an image processing device 1, a projection mapping processing unit 21 of a processing unit 10 performs texture image projection mapping on a background object in plural directions. In the image processing device 1, an environment mapping processing unit 23 performs environment mapping processing on the basis of environment map image data 34 acquired from a secondary storage unit 12 by an environment map image acquisition processing unit 22, to acquire a blend coefficient required for blend processing performed by a blend processing unit 24. The blend processing unit 24 performs blend processing on plural texture images in accordance with the acquired blend coefficient. The environment mapping processing unit 23 calculates a reflection vector indicating the reflection of a ray vector from a light source on the surface of the background object and acquires a pixel value corresponding to the reflection vector as a blend coefficient from an environment map image.

Description

  The present invention relates to an image processing method, an image processing program, an image processing apparatus, and an image processing system for performing image processing related to three-dimensional computer graphics.

  Conventionally, three-dimensional computer graphics (hereinafter referred to as 3DCG) are widely used in, for example, computer games, movies, and CAD (Computer Aided Design) systems. In recent 3DCG, image processing for improving the surface texture of a three-dimensional object by pasting a prepared image (texture) on the surface of a three-dimensional object expressed by a combination of a plurality of polygonal surfaces (polygons). Is done. This image processing is called texture mapping.

  Patent Document 1 describes an image processing apparatus that performs UV mapping as texture mapping. In the image processing apparatus of Patent Document 1, a reference address generation unit receives UV coordinates from a shader, converts them to a reference address for referring to a texture, and refers to a texture map stored in a texture memory based on the reference address. The image processing apparatus supplies the referenced value to the interpolation unit, and the interpolation unit performs texture mapping processing, generates a color value corresponding to the UV coordinate value of the pixel, and supplies the color value to the shader. Further, the image processing apparatus of Patent Document 1 refers to an instruction map based on a reference address, and gives a shader a control signal for executing the referenced instruction, thereby causing the shader to execute a different instruction for each pixel. It is possible.

JP 2006-146721 A

  UV mapping, which is widely used as a method for texture mapping, is a method of pasting by associating the three-dimensional coordinates of a solid object to which a texture is to be pasted with the two-dimensional coordinates (UV coordinates) of a texture image. is there. Since this association is maintained even when the three-dimensional object is deformed, distortion occurs in the pasted texture when the three-dimensional object is deformed. For example, when the size of one polygon constituting the three-dimensional model is enlarged in one direction, the texture pasted on this polygon is stretched in the polygon enlargement direction, resulting in a distorted image.

  As other methods of texture mapping, various algorithms such as projection mapping, lap mapping, solid texture mapping, bump mapping, environment mapping, displacement mapping, and transparency mapping are used.

  An object of the present invention is to provide an image processing method, an image processing program, an image processing apparatus, and an image processing system that realize a texture mapping process that enables an excellent aesthetic 3D image display.

  An image processing method according to the present invention is an image processing method in which a texture image is pasted on a three-dimensional object composed of a plurality of surfaces, which is composed of a plurality of pixels, and is used for synthesizing a plurality of texture images for each pixel. An environment map image acquisition step for acquiring an environment map image in which a synthesis coefficient is set, and an environment mapping process for the three-dimensional object using the environment map image acquired in the environment map image acquisition step. A mapping step for identifying a pixel in the environment map image corresponding to each pixel of the texture image to be pasted, obtaining a synthesis coefficient set for the identified pixel, and pasting for pasting a plurality of texture images to the solid object Step and the composition unit acquired in the mapping step Depending on, characterized in that it comprises a synthesizing step of synthesizing a plurality of texture images attached on the solid object surface.

  The image processing method according to the present invention is characterized in that the pasting of the plurality of texture images in the pasting step is performed by projection mapping in a plurality of different projection directions.

  The image processing method according to the present invention is an image processing method for pasting a texture image onto a three-dimensional object composed of a plurality of surfaces, and is a predetermined direction projection for projecting and mapping a texture image from a predetermined direction on the three-dimensional object. A mapping step, an environment map image acquisition step for acquiring an environment map image that is composed of a plurality of pixels, and in which a combination coefficient used for combining a plurality of texture images is set for each pixel; and the environment map image acquisition step Based on the environment mapping process for the three-dimensional object using the environment map image acquired in this way, the pixel in the environment map image corresponding to each pixel of the texture image attached to the surface of the three-dimensional object is specified and set to the specified pixel. Mapping step to get the combined coefficient A projection mapping step for projecting and mapping a texture image from a direction different from the projection direction of the texture image that has been projected and mapped to the three-dimensional object, and the projection mapping according to the synthesis coefficient acquired in the mapping step A synthesis step of synthesizing the already textured image and the texture image projected and mapped from different directions, and repeatedly performing the mapping step, the different-direction projection mapping step and the synthesis step, A texture image is pasted from the direction.

  In the image processing method according to the present invention, an alpha value is set as the synthesis coefficient in the environment map image, and in the synthesis step, the pixel values of a plurality of texture images are synthesized by alpha blending. It is characterized by.

  In the image processing method according to the present invention, in the environment mapping process, a reflection vector for a light vector from a light source to the surface of the three-dimensional object is calculated, and a pixel of the environment map image corresponding to the calculated reflection vector is specified. The synthesis coefficient set for the specified pixel is obtained from the environment map image.

  The image processing method according to the present invention is characterized in that the three-dimensional object is a three-dimensional object constituting the background of a virtual space including a moving body and a background.

  An image processing program according to the present invention is an image processing program for causing a computer to paste a texture image on a solid object composed of a plurality of surfaces, the computer being composed of a plurality of pixels, and each pixel An environment map image acquisition means for acquiring an environment map image in which a synthesis coefficient used for combining a plurality of texture images is set, and an environment mapping process for the solid object using the environment map image acquired by the environment map image acquisition means A mapping means for identifying a pixel in the environment map image corresponding to each pixel of the texture image to be pasted on the surface of the solid object, and obtaining a synthesis coefficient set for the identified pixel; Pasting means for pasting a plurality of texture images, Mappings means in response to the acquired combination coefficient, characterized in that operate as synthesizing means for synthesizing the plurality of texture images attached to the solid object surface.

  An image processing program according to the present invention is an image processing program for causing a computer to paste a texture image onto a solid object composed of a plurality of surfaces. A predetermined direction projection mapping means for projecting mapping, an environment map image obtaining means for obtaining an environment map image that is composed of a plurality of pixels, and each pixel is set with a synthesis coefficient used to synthesize a plurality of texture images; Based on the environment mapping process for the three-dimensional object using the environment map image acquired by the environment map image acquiring means, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the three-dimensional object is specified. , The composition factor set for the specified pixel A mapping unit to obtain, a different direction projection mapping unit for project mapping a texture image from a direction different from a projection direction of a projection mapped texture image with respect to the solid object, and a synthesis coefficient obtained by the mapping unit. Accordingly, the computer is operated as a synthesis unit that synthesizes the texture image that has been subjected to projection mapping and the texture image that has been projected and mapped from different directions, and the computer acquires a synthesis coefficient by the mapping unit, and the texture image by the different direction projection mapping unit. Projection mapping and texture image synthesis by the synthesis means are repeatedly performed, and texture images are pasted to the solid object from a plurality of directions.

  An image processing apparatus according to the present invention is an image processing apparatus that performs a process of pasting a texture image on a three-dimensional object composed of a plurality of surfaces, and includes a plurality of pixels, and each pixel includes a plurality of textures. Based on environment map image acquisition means for acquiring an environment map image in which a synthesis coefficient used for image synthesis is set, and environment mapping processing for the solid object using the environment map image acquired by the environment map image acquisition means, Mapping means for specifying a pixel in the environment map image corresponding to each pixel of the texture image to be pasted on the surface of the three-dimensional object, and obtaining a synthesis coefficient set for the specified pixel; and a plurality of textures for the three-dimensional object Depending on the pasting means for pasting the image and the synthesis coefficient obtained by the mapping means , Characterized in that it comprises a synthesizing means for synthesizing the plurality of texture images attached to the solid object surface.

  The image processing apparatus according to the present invention is an image processing apparatus that performs a process of pasting a texture image on a three-dimensional object composed of a plurality of surfaces, and projects and maps the texture image on the three-dimensional object from a predetermined direction. A predetermined direction projection mapping unit, an environment map image acquisition unit configured to acquire an environment map image which is configured by a plurality of pixels, and each pixel is set with a synthesis coefficient used to synthesize a plurality of texture images, and the environment map image Based on the environment mapping process for the solid object using the environment map image acquired by the acquisition unit, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the solid object is specified, and the specified pixel Mapping means for obtaining a composite coefficient set to A projection mapping unit that projects and maps a texture image from a direction different from the projection direction of the texture image that has been projected mapped to the object, and the projection mapped image according to the synthesis coefficient acquired by the mapping unit. A synthesis unit that synthesizes a texture image and a texture image that has been projected and mapped from the different directions, acquisition of a synthesis coefficient by the mapping unit, projection mapping of the texture image by the different direction projection mapping unit, and a texture image by the synthesis unit A texture mapping unit that repeatedly performs synthesis and pastes texture images from a plurality of directions on the three-dimensional object.

  An image processing system according to the present invention is an image processing system that performs processing of pasting a texture image on a three-dimensional object composed of a plurality of surfaces, and includes a plurality of pixels, and each pixel includes a plurality of textures. Based on environment map image acquisition means for acquiring an environment map image in which a synthesis coefficient used for image synthesis is set, and environment mapping processing for the solid object using the environment map image acquired by the environment map image acquisition means, Mapping means for specifying a pixel in the environment map image corresponding to each pixel of the texture image to be pasted on the surface of the three-dimensional object, and obtaining a synthesis coefficient set for the specified pixel; and a plurality of textures for the three-dimensional object A pasting unit for pasting an image, and a composition unit acquired by the mapping unit Depending on, characterized in that it comprises a synthesizing means for synthesizing the plurality of texture images attached to the solid object surface.

  The image processing system according to the present invention is an image processing system that performs a process of pasting a texture image on a three-dimensional object composed of a plurality of surfaces, and projects and maps the texture image to the three-dimensional object from a predetermined direction. A predetermined direction projection mapping unit, an environment map image acquisition unit configured to acquire an environment map image which is configured by a plurality of pixels, and each pixel is set with a synthesis coefficient used to synthesize a plurality of texture images, and the environment map image Based on the environment mapping process for the solid object using the environment map image acquired by the acquisition unit, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the solid object is specified, and the specified pixel A mapping means for obtaining the synthesis coefficient set to A projection mapping means for projecting a texture image from a direction different from the projection direction of the texture image that has been projected and mapped to the three-dimensional object, and the projection mapping is performed according to the synthesis coefficient obtained by the mapping means. A texture image and a texture image projected and mapped from different directions, a synthesis coefficient obtained by the mapping means, a texture image projection mapping by the different direction projection mapping means, and a texture image by the synthesis means And a texture mapping unit that repeats the above synthesis and pastes texture images from a plurality of directions on the three-dimensional object.

  In the present invention, instead of setting image data such as the surrounding landscape in the environment map image, a synthesis coefficient (blend coefficient) necessary for synthesizing (blending) a plurality of texture images is set for each pixel of the environment map image. Set to. By performing environment mapping processing using this environment map image, a blend coefficient corresponding to the reflection direction on the surface of the three-dimensional object can be acquired, and a plurality of texture images can be blended using this blend coefficient.

  In the present invention, a plurality of texture images are projected and mapped to a three-dimensional object. Projection mapping is a technique for pasting a texture image by arranging a texture image on a coordinate system in which a three-dimensional object exists and projecting the texture image toward the three-dimensional object. For this reason, in the projection mapping, even when the shape of the three-dimensional object changes, the pasted texture image is not distorted.

  In general, in the environment mapping process, a reflection vector in which a ray from a light source, a line of sight from a viewpoint (camera), or a vector obtained by combining the ray and the line of sight is reflected on the surface of a three-dimensional object is calculated, and this reflection vector The pixel of the environment map image is specified, and the pixel value of the specified pixel is acquired from the environment map image. In the present invention, an environment mapping process based on light rays from a light source is performed to obtain a blend coefficient from an environment map image. This is because the position of the viewpoint may change, and when the viewpoint moves, the blend coefficient acquired by the environment mapping process changes and the result of the blend process changes. On the other hand, the position of the light source is unlikely to change, and the result of the blend process does not change even if the viewpoint moves.

  In the present invention, an alpha value is set as a blending coefficient in the pixel value of the environment map image. By performing environment mapping processing using this environment map image, an alpha value corresponding to the normal direction of the surface of the three-dimensional object can be acquired, and a plurality of texture images can be alpha blended.

  According to the present invention, the blending process can be easily realized by acquiring the blending coefficient based on the environment mapping process and performing the blending process of the plurality of texture images. Moreover, even if the shape of the three-dimensional object changes by projecting and mapping the texture image from a plurality of different directions on the three-dimensional object, the texture image to be pasted is not distorted.

It is a block diagram which shows the structure of the image processing apparatus which concerns on embodiment of this invention. It is a schematic diagram which shows an example of the three-dimensional image which an image processing apparatus displays on a display apparatus. It is a schematic diagram for demonstrating the projection mapping process which an image processing apparatus performs. It is a schematic diagram for demonstrating the environment mapping process which an image processing apparatus performs. It is a schematic diagram which shows an example of an environment map image. It is a flowchart which shows the procedure of the texture mapping process which an image processing apparatus performs. It is a block diagram which shows the example of 1 structure of the image processing system which concerns on a modification.

  Hereinafter, the present invention will be specifically described with reference to the drawings showing embodiments thereof. FIG. 1 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention. In the figure, reference numeral 1 denotes an image processing apparatus, which is realized as, for example, a stationary game machine. The image processing device 1 is connected to a display device 5 such as a liquid crystal display or a PDP (Plasma Display Panel) via a video signal cable, and outputs a digital or analog image signal. The display device 5 performs various image processing including a three-dimensional image based on the image signal given from the image processing device 1.

  The image processing apparatus 1 includes a processing unit 10 configured using an arithmetic processing device such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit). The processing unit 10 reads out and executes a game program (not shown) pre-stored in the secondary storage unit 12 to the primary storage unit 11 to execute various arithmetic processes (for example, function as a game machine) (for example, A process of determining an operation on the operation unit 14 by the user and a process of updating an image displayed on the display device 5 according to the operation content are performed. The image processing apparatus 1 according to the present embodiment has a 3DCG image processing function, and the processing unit 10 executes an image processing program 31 stored in advance in the secondary storage unit 12 to perform image processing related to 3DCG. Then, the processed image is output from the image output unit 13 to display an image on the display device 5.

  The primary storage unit 11 of the image processing apparatus 1 is configured using a memory element such as an SRAM (Static Random Access Memory) or a DRAM (Dynamic Random Access Memory). The primary storage unit 11 reads and stores various programs and data necessary for processing performed by the processing unit 10 from the secondary storage unit 12, and generates various programs and data generated in accordance with the arithmetic processing of the processing unit 10. Data is temporarily stored.

  The secondary storage unit 12 of the image processing apparatus 1 is configured by using a large-capacity nonvolatile storage device (compared to the primary storage unit 11) such as a hard disk or a flash memory. The secondary storage unit 12 stores (installs) programs and data downloaded by the communication unit 15 from an external server device (not shown) and the like, and programs and data read from the recording medium 9 by the disk drive 16 (installation). )

  The image output unit 13 of the image processing apparatus 1 reads the image data processed by the processing unit 10 from the primary storage unit 11 in accordance with an instruction from the processing unit 10, and converts the read image data into an image signal in a predetermined format. And output to the display device 5. The operation unit 14 of the image processing apparatus 1 includes a game controller connected by wire or wireless in addition to a switch provided in the apparatus main body of the image processing apparatus 1, and receives an operation by the user to the processing unit 10. Notice.

  The communication unit 15 of the image processing apparatus 1 transmits / receives data to / from an external apparatus via a wired or wireless local area network (LAN) or a public mobile phone network. By providing the image processing apparatus 1 with a communication function, the user can download a game program (including the image processing program 31 and various data) from an external server device and store it in the secondary storage unit 12. Further, the user can use the communication function of the communication unit 15 to play the same game as another user in a remote place in cooperation or against.

  The disk drive 16 of the image processing apparatus 1 is configured such that an optical disk type recording medium 9 such as a CD (Compact Disc), a DVD (Digital Versatile Disk), or a Blu-ray disc is detachable. The disk drive 16 reads out the game program (including the image processing program 31 and various data) recorded on the attached recording medium 9 and stores it in the secondary storage unit 12. The game program recorded in the disk drive 16 is not stored in the secondary storage unit 12 in advance, but the processing unit 10 directly stores the game program from the recording medium 9 mounted in the disk drive 16. 11 may be read and executed.

  As described above, the image processing apparatus 1 performs various image processing related to 3DCG by executing the image processing program 31 in the processing unit 10. In the block diagram of FIG. 1, four blocks related to 3DCG texture mapping processing are described in the processing unit 10. These four blocks are software functional blocks realized by the processing unit 10 executing the image processing program. The secondary storage unit 12 describes three types of data, that is, three-dimensional object data 32, texture image data 33, and environment map image data 34, as data used for the texture mapping process. These data are installed in the secondary storage unit 12 from the recording medium 9 or the like together with the game program.

  Next, the texture mapping process performed by the image processing apparatus 1 according to the present embodiment will be described. FIG. 2 is a schematic diagram illustrating an example of a three-dimensional image displayed on the display device 5 by the image processing apparatus 1. In the illustrated example, a three-dimensional character object 101 that can be operated (moved) by the user using the operation unit 14 is arranged on a background on which a large number of background objects 102 such as rocks are arranged. It is a virtual space. The image processing apparatus 1 generates a two-dimensional image obtained by visually recognizing the three-dimensional virtual space from a specific viewpoint, and outputs the image to the display apparatus 5 by outputting the image as an image signal from the image output unit 13. Display.

  A solid object such as the character object 101 and the background object 102 arranged in the three-dimensional virtual space is represented by a combination of many polygons, and a texture image is pasted on the surface of the solid object (polygon surface). It has been. The image processing apparatus 1 stores information related to a three-dimensional object (for example, vertex coordinates of polygons) in the secondary storage unit 12 as three-dimensional object data 32. Further, the image processing apparatus 1 stores texture image information to be pasted on the three-dimensional object in the secondary storage unit 12 as texture image data 33.

  The processing unit 10 of the image processing apparatus 1 performs a process of pasting a texture image on the surface of the character object 101 using, for example, a UV mapping algorithm (however, another algorithm may be used). UV mapping is an algorithm that pastes a predetermined range of a texture image onto a predetermined polygon of a three-dimensional object by associating the three-dimensional coordinates (XYZ) of the character object 101 with the two-dimensional coordinates (UV) of the texture image. is there.

  The processing unit 10 pastes the texture image on the background object 102 using a projection mapping algorithm. FIG. 3 is a schematic diagram for explaining the projection mapping process performed by the image processing apparatus 1. Projection mapping is an algorithm for pasting and pasting a two-dimensional texture image onto the surface of a three-dimensional object. Conventionally, with respect to any one of the coordinate axes of the X axis direction, Y axis direction, or Z axis direction in three-dimensional coordinates Projection in parallel. On the other hand, the processing unit 10 of the image processing apparatus 1 according to the present embodiment applies texture images to the background object 102 from the three directions of the X-axis direction, the Y-axis direction, and the Z-axis direction in the three-dimensional coordinates. The projection mapping processing unit 21 performs a projection mapping process.

  For example, the projection mapping processing unit 21 of the processing unit 10 first projects and maps the texture image 105z arranged parallel to the XY plane onto the background object 102 in the Z-axis direction. Next, the projection mapping processor 21 performs projection mapping of the texture image 105x arranged in parallel with the YZ plane onto the background object 102 in the X-axis direction. Further, the projection mapping processing unit 21 projects and maps the texture image 105y arranged in parallel with the ZX plane onto the background object 102 in the Y-axis direction. The plurality of texture images 105x to 105z may be the same image or different images.

  When a plurality of texture images are projected and mapped onto one background object 102 in this way, there are places where a plurality of texture images are projected on the surface of the background object 102. Therefore, the processing unit 10 performs a process of blending a plurality of texture images on the portion where the texture images overlap with each other in the blend processing unit 24. In the present embodiment, the blend processing unit 24 of the processing unit 10 uses an alpha blending algorithm as the blending process (however, the alpha blending is an example, and the blending processing unit 24 performs a blending process using another algorithm. May be good).

Alpha blending is an algorithm that synthesizes two images based on a coefficient (alpha value) representing transmittance, and performs an operation according to the following equation (1) for each pixel of the image. In equation (1), a is the pixel value of the first image, b is the pixel value of the second image, c is the pixel value of the combined image, and α is the alpha value. However, 0 ≦ α ≦ 1.
c = a × (1−α) + b × α (1)

  For example, the blend processing unit 24 of the processing unit 10 sets the texture image 105z as the first image when the projection mapping processing unit 21 projects and maps the texture image 105x to the background object 102 to which the texture image 105z is pasted. The alpha blend process based on the formula (1) is performed using the texture image 105x as the second image. Next, when the projection mapping processing unit 21 further projects and maps the texture image 105y onto the background object 102, the blend processing unit 24 sets the blended texture images 105z and 105x as the first image and the texture image 105y as the second image. Alpha blend processing is performed as an image.

  The blend processing unit 24 acquires an alpha value in order to perform blend processing. In the processing unit 10 of the image processing apparatus 1 according to the present embodiment, the blend processing unit 24 performs alpha blending with an alpha value corresponding to the normal vector of each polygon constituting the background object 102. Therefore, the processing unit 10 acquires the environment map image data 34 stored in the secondary storage unit 12 by the environment map image acquisition processing unit 22, and the environment mapping processing unit 23 uses the environment map image data 34 to perform environment mapping. By performing the processing, an alpha value corresponding to the normal vector of each polygon is acquired.

  FIG. 4 is a schematic diagram for explaining the environment mapping process performed by the image processing apparatus 1. In general, environment mapping is an image processing algorithm that is used to represent the reflection of the surrounding environment on an object. In environment mapping for expressing reflection, an environment surrounding an object is prepared in advance as an environment map image, and the environment map image is pasted on the inner surface of a virtual sphere or cube surrounding the object. Next, the reflection vector at the intersection of the ray vector or line-of-sight vector and the object is calculated, the intersection of the reflection vector and the virtual sphere or cube is specified, and the pixel value of the environment map image at the intersection is reflected on the object surface To express the reflection.

  The environment map image 205 that the image processing apparatus 1 according to the present embodiment stores as the environment map image data 34 in the secondary storage unit 12 is not an image of the surrounding environment, but an alpha value is set for each pixel. . The environment mapping processing unit 23 of the processing unit 10 calculates the intersection of the light vector 202 from the light source 201 and the background object 102. The environment mapping processing unit 23 calculates a reflection vector 204 of the light vector 202 based on the polygon normal vector 203 at the calculated intersection. Next, the environment mapping processing unit 23 specifies the pixel at the intersection of the reflection vector 204 and the environment map image 205, and acquires the pixel value (alpha value) of the specified pixel.

  The environment mapping processing unit 23 acquires the alpha value of the intersection of the reflection vector 204 and the environment map image 205 at each point on the surface of the background object 102 (a point corresponding to each pixel of the pasted texture image), and blend processing To part 24. The blend processing unit 24 performs alpha blending of the texture image based on the formula (1) at each point on the surface of the background object 102 according to the alpha value given from the environment mapping processing unit 23. At this time, the blend processing unit 24 blends one or a plurality of texture images that have already been pasted (blended) as the first image of the above formula (1), and the newly pasted texture image as the second image. Can be done.

  The environment map image 205 used for the environment mapping process is created in advance by a game designer or designer. FIG. 5 is a schematic diagram showing an example of the environment map image 205. The upper part shows an overall view of the environment map image 205, and the lower part shows a partially enlarged view. In the environment map image 205, for example, a pixel value of 256 gradations of 0 to 255 can be set for each pixel, and a value obtained by dividing the pixel value of each pixel by 255 is an alpha value. In FIG. 5, the environment map image 205 is shown as a grayscale image of 256 gradations.

  The environment map image 205 shown as an example in FIG. 5 has a predetermined width portion at the left and right ends in black, and a predetermined width portion at the center is white, and the brightness gradually increases from the left and right black to the central white. This is an image with gradation so that the image becomes higher. (However, FIG. 5 shows an image in which the brightness is changed stepwise from black to white, but it may be an image in which the brightness is continuously changed.)

  Further, the color change in the horizontal direction of the environment map image 205 does not need to be uniform in the vertical direction, and the arrangement of the pixels of each color may vary as shown in the lower part of FIG. This variation may be based on the judgment of a designer or a designer, for example, or may be automatically generated based on, for example, a random number. By varying the color change of the environment map image 205, the alpha value for the reflection vector 204 can be varied. As a result, the blend processing unit 24 can vary the texture image blending process, and can include noise expression in a pattern or the like pasted on the surface of the background object 102.

  FIG. 6 is a flowchart showing the procedure of the texture mapping process performed by the image processing apparatus 1, and is a process performed by the processing unit 10 executing the image processing program 31. First, the processing unit 10 of the image processing apparatus 1 performs processing for reading data necessary for texture mapping processing from the secondary storage unit 12. Specifically, the processing unit 10 reads and acquires the three-dimensional object data 32 including the data related to the background object 102 from the secondary storage unit 12 (step S1). Further, the processing unit 10 reads out and obtains the texture image data 33 including the plurality of texture images 105x to 105z to be pasted on the background object 102 from the secondary storage unit 12 (step S2). Further, the processing unit 10 reads out and acquires the environment map image data 34 including the environment map image 205 in which the alpha value is set as the blend coefficient from the secondary storage unit 12 (step S3).

  Next, the processing unit 10 sets a variable n = 1 (step S4). Note that the variable n is a variable for distinguishing the direction of projection mapping by the projection mapping processing unit 21, and 1 ≦ n ≦ N. For example, in FIG. 3, the variable n = 1 corresponds to the projection mapping from the Z-axis direction, the variable n = 2 corresponds to the projection mapping from the X-axis direction, and the variable n = 3 corresponds to the Y-axis. It can correspond to the projection mapping from the direction. The constant N is the number of directions in which projection mapping is performed, and N = 3 in the example of FIG. The variable n is secured in a storage area such as a register in the processing unit 10 or the primary storage unit 11.

  Next, the processing unit 10 performs a process of projecting and mapping the nth texture image from the nth direction on the background object 102 that is the target of the texture mapping in the projection mapping processing unit 21 (step S5). Note that the nth texture image is an image prepared for performing projection mapping on the background object 102 from the nth direction. However, the processing unit 10 does not need N texture images when the projection mapping processing unit 21 performs the projection mapping processing from all N directions. For example, the i-th texture image and the i + 1-th texture image may be the same texture image.

  Thereafter, the processing unit 10 adds 1 to the value of the variable n (step S6). The processing unit 10 determines one point (pixel) on the surface of the polygon constituting the background object 102 as a processing target point (step S7). Next, the processing unit 10 performs an environment mapping process in the environment mapping processing unit 23 based on the environment map image 105 read in step S3. Thereby, the processing unit 10 acquires the blend coefficient (alpha value) set in the pixel of the environment map image 205 corresponding to the reflection vector 204 of the ray vector 202 from the light source 201 with respect to the processing target point of the background object 102 (step). S8).

  Next, the processing unit 10 performs projection mapping of the nth texture image on the background object 102 from the nth direction in the projection mapping processing unit. Further, the processing unit 10 determines the pixel value of the previous texture image (an image obtained by blending the first texture image to the (n-1) th texture image) in the blend processing unit 24 according to the blend coefficient acquired in step S8, Blending (alpha blending) with the pixel values of the nth texture image subjected to projection mapping is performed (step S9).

  After the blending process, the processing unit 10 determines whether or not the texture mapping process for the nth direction has been completed for all points of the background object 102 (step S10). If the texture mapping process has not been completed for all points (S10: NO), the processing unit 10 returns the process to step S7 and repeats the processes of steps S7 to S9.

  When the texture mapping process is completed for all points (S10: YES), the processing unit 10 determines whether or not the variable n = N is satisfied (that is, whether the texture mapping process is completed for all directions). Determination is made (step S11). When the variable n ≠ N (S11: NO), the processing unit 10 returns the process to step S6 and repeats the processes of steps S6 to S10. When the variable n = N is satisfied (S11: YES), the processing unit 10 ends the texture mapping process.

  In the image processing apparatus 1 having the above configuration, the projection mapping processing unit 21 of the processing unit 10 performs texture image projection mapping on the background object 102 from a plurality of directions. Since the image processing apparatus 1 is configured to perform projection mapping as texture mapping, for example, even when the shape of the background object 102 changes due to an event in the game, the image to be pasted is distorted. There is no. In addition, the image processing apparatus 1 can apply a texture image to the surface of the background object 102 without omission by adopting a configuration in which projection mapping is performed from a plurality of directions.

  Further, in the image processing apparatus 1, the environment mapping processing unit 23 performs the environment mapping process based on the environment map image data 34 acquired by the environment map image acquisition processing unit 22 from the secondary storage unit 12, whereby the blend processing unit 24. The blending coefficient necessary for the blending process performed by is acquired. The image processing apparatus 1 can acquire a blend coefficient corresponding to a normal vector on the surface of the background object 102 by adopting a configuration in which the blend coefficient is acquired by the environment mapping process. In addition, since the image processing apparatus 1 is configured to be able to change the processing result of the blend process by changing the pixel value of each pixel of the environment map image, a programmer or the like does not change the image processing program 31. Designers can easily change the processing result of the blending process by changing the environment map image.

  In the image processing apparatus 1, the environment mapping processing unit 23 calculates the reflection vector 204 in which the light vector 202 from the light source 201 is reflected from the surface of the background object 102, and specifies the pixel of the environment map image 205 corresponding to the reflection vector 204. The blend coefficient (alpha value) set for the identified pixel is acquired. This is because when the environment mapping process is performed from the viewpoint based on the line-of-sight vector, the viewpoint may move during the game. When the viewpoint moves, the result of the environment mapping process changes and the result of the blend process changes. Because. However, when the viewpoint does not move during the game, the environment mapping processing unit 23 may perform environment mapping processing based on the line-of-sight vector. The environment mapping processing unit 23 may be configured to set a fixed point in a three-dimensional virtual space and perform environment mapping processing based on a vector from the fixed point to the background object 102.

  In the present embodiment, the image processing apparatus 1 outputs an image signal from the image output unit 13 to the display apparatus 5 to display an image on the display apparatus 5. However, the present invention is not limited to this. The image processing apparatus 1 may be configured to include a display unit such as a liquid crystal panel or a PDP and display an image on the display unit. The image processing apparatus 1 is a stationary game machine, but is not limited to this. The image processing apparatus 1 may be a portable game device or a general-purpose computer that can execute a game program. The image processing apparatus 1 may be an apparatus other than a game machine, for example, a mobile phone or a smartphone, or may be an apparatus that displays 3DCG such as a CAD or a simulator.

  Further, the projection mapping processing unit 21 to the blend processing unit 24 of the processing unit 10 of the image processing apparatus 1 are realized by software by the processing unit 10 executing the image processing program 31, but the present invention is not limited thereto. is not. A part or all of the projection mapping processing unit 21 to the blend processing unit 24 of the image processing apparatus 1 may be realized in hardware. The image processing apparatus 1 is configured such that the processing unit 10 performs processing such as game determination and image processing, but is not limited thereto. The image processing apparatus 1 may be configured to include an image processing unit such as a GPU (Graphics Processing Unit) that performs image processing separately from the processing unit 10. In this case, the projection mapping processing unit 21 to the blend processing unit 24 include Provided in the image processing unit.

  Further, the projection mapping processing unit 21 of the image processing apparatus 1 is configured to perform the projection mapping process from the three directions of the X-axis direction, the Y-axis direction, and the Z-axis direction, but is not limited thereto. The projection mapping processing unit 21 may be configured to perform projection mapping processing from two directions or four or more directions. In addition, the image processing apparatus 1 performs the above-described image processing for blending a texture image obtained by projection mapping processing from a plurality of directions based on the blend coefficient acquired by the environment mapping processing on the background object 102 in the three-dimensional virtual space. However, the present invention is not limited to this. The image processing apparatus 1 may be configured to perform the above-described image processing on other objects such as the character object 101. The environment map image 205 shown in FIG. 5 is an example, and the present invention is not limited to this. The environment map image 205 can be appropriately created by a game designer or the like so as to suit various factors such as the shape of the background object 102, the type of texture image, and the game content.

  The image processing apparatus 1 according to the above-described embodiment is configured to perform all of the texture mapping processing for the background object 102 by itself, but is not limited thereto. A configuration may be adopted in which image processing such as projection mapping processing, environment mapping processing, and blend processing necessary for texture mapping processing is performed by a plurality of devices. In the following modification, an image processing system that performs texture mapping processing in a distributed manner by a plurality of image processing apparatuses will be described.

(Modification)
FIG. 7 is a block diagram illustrating a configuration example of an image processing system according to a modification. The image processing system according to the modification includes a first image processing device 1a and a second image processing device 1b. The first image processing device 1 a has substantially the same configuration as the image processing device 1 shown in FIG. 1, but the environment map image acquisition processing unit 22 and the environment mapping processing unit 23 are not provided in the processing unit 10. The processing unit 10 of the first image processing apparatus 1a includes a projection mapping processing unit 21 and a blend processing unit 24.

  The second image processing apparatus 1b also has substantially the same configuration as that of the image processing apparatus 1 shown in FIG. 1, but may be configured without the operation unit 14 and the disk drive 16. In the second image processing apparatus 1b, the environment map image acquisition processing unit 22 and the environment mapping processing unit 23 are provided in the processing unit 10, and the projection mapping processing unit 21 and the blend processing unit 24 are not provided. In the first image processing apparatus 1a and the second image processing apparatus 1b, the communication units 15 are connected to each other via a communication line, a LAN (Local Area Network), or the like, and can transmit / receive data to / from each other.

  When texture mapping is performed on the background object 102, the first image processing apparatus 1a performs projection mapping of a texture image from a plurality of directions and blend processing of a plurality of texture images in the projection mapping processing unit 21 and the blend processing unit 24. Do. In the second image processing apparatus 1b, the environment map image acquisition processing unit 22 and the environment mapping processing unit 23 perform a process of acquiring a blend coefficient (alpha value) by performing an environment mapping process. The second image processing apparatus 1b transmits the alpha value acquired by the environment mapping process to the first image processing apparatus 1a via the communication unit 15. The first image processing device 1a receives an alpha value from the second image processing device 1b, and performs a blend process by the blend processing unit 24 using the received alpha value.

  Information such as the image processing program 31, the three-dimensional object data 32, the texture image data 33, and the environment map image data 34 is stored in the secondary storage unit 12 of the first image processing apparatus 1a or the secondary image of the second image processing apparatus 1b. It may be stored in any of the storage units 12. For example, when all of these pieces of information are stored in the secondary storage unit 12 of the first image processing apparatus 1a, the first image processing apparatus 1a transmits necessary information to the second image processing apparatus 1b in the communication unit 15. Send to.

  As described above, by adopting a configuration in which processing related to texture mapping is performed by a plurality of image processing apparatuses 1a and 1b being distributed, for example, projection mapping processing and environment mapping processing can be performed in parallel. The processing time can be shortened. The image processing system shown in FIG. 7 has a configuration in which the first image processing apparatus 1a performs the projection mapping process and the blending process, and the second image processing apparatus 1b performs the environment mapping process. It is not a thing. For example, the first image processing device 1a may perform blending processing, and the second image processing device 1b may perform other types of projection mapping processing and environment mapping processing. In addition, an image processing system including three image processing apparatuses may be used. In this case, the projection mapping process, the environment mapping process, and the blending process may be performed by different image processing apparatuses.

1, 1a, 1b Image processing device 5 Display device 9 Recording medium 10 Processing unit (texture mapping means)
DESCRIPTION OF SYMBOLS 11 Primary storage part 12 Secondary storage part 15 Communication part 21 Projection mapping process part (predetermined direction projection mapping means, different direction projection mapping means)
22 Environment map image acquisition processing unit (environment map image acquisition means)
23 Environment mapping processor (mapping means)
24 Blend processing unit (combining means)
DESCRIPTION OF SYMBOLS 31 Image processing program 32 Three-dimensional object data 33 Texture image data 34 Environment map image data 101 Character object 102 Background object 105x-105z Texture image 201 Light source 202 Ray vector 203 Normal vector 204 Reflection vector 205 Environment map image

Claims (12)

An image processing method for pasting a texture image to a three-dimensional object composed of a plurality of surfaces,
An environment map image acquisition step configured to acquire an environment map image which is configured by a plurality of pixels and in which a synthesis coefficient used for synthesis of a plurality of texture images is set for each pixel;
Based on the environment mapping process for the three-dimensional object using the environment map image acquired in the environment map image acquisition step, the pixel in the environment map image corresponding to each pixel of the texture image attached to the surface of the three-dimensional object is specified. A mapping step for obtaining a synthesis coefficient set for the identified pixel;
A pasting step of pasting a plurality of texture images to the solid object;
An image processing method comprising: a combining step of combining a plurality of texture images attached to the surface of the three-dimensional object according to the combining coefficient acquired in the mapping step. The image processing method according to claim 1, wherein the pasting of the plurality of texture images in the pasting step is performed by projection mapping in a plurality of different projection directions. An image processing method for pasting a texture image to a three-dimensional object composed of a plurality of surfaces,
A predetermined direction projection mapping step of projecting and mapping a texture image from a predetermined direction to the solid object;
An environment map image acquisition step configured to acquire an environment map image which is configured by a plurality of pixels and in which a synthesis coefficient used for synthesis of a plurality of texture images is set for each pixel;
Based on the environment mapping process for the three-dimensional object using the environment map image acquired in the environment map image acquisition step, the pixel in the environment map image corresponding to each pixel of the texture image attached to the surface of the three-dimensional object is specified. A mapping step for obtaining a synthesis coefficient set for the identified pixel;
A different-direction projection mapping step for projecting and mapping a texture image from a direction different from the projection direction of the texture image that has been projected and mapped to the three-dimensional object;
Combining a texture image that has been projected and mapped and a texture image that has been projected and mapped from the different direction according to the synthesis coefficient acquired in the mapping step, and
An image processing method comprising: repeatedly performing the mapping step, the different-direction projection mapping step, and the combining step, and pasting texture images from a plurality of directions on the solid object. In the environment map image, an alpha value is set as the synthesis coefficient,
4. The image processing method according to claim 1, wherein in the synthesis step, the pixel values of the plurality of texture images are synthesized by alpha blending. 5. In the environment mapping process, a reflection vector for a light ray vector from a light source to the surface of the solid object is calculated, a pixel of the environment map image corresponding to the calculated reflection vector is specified, and a synthesis coefficient set for the specified pixel is determined. 5. The image processing method according to claim 1, wherein the image processing method is acquired from the environment map image. The image processing method according to claim 1, wherein the three-dimensional object is a three-dimensional object constituting the background of a virtual space including a moving body and a background. An image processing program for causing a computer to paste a texture image on a three-dimensional object composed of a plurality of surfaces,
Computer
An environment map image acquisition unit configured to acquire an environment map image configured by a plurality of pixels, in which a combination coefficient used for combining a plurality of texture images is set for each pixel;
Based on the environment mapping process for the three-dimensional object using the environment map image acquired by the environment map image acquiring means, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the three-dimensional object is specified. Mapping means for obtaining a synthesis coefficient set for the specified pixel;
Pasting means for pasting a plurality of texture images to the three-dimensional object;
An image processing program that is operated as a synthesis unit that synthesizes a plurality of texture images pasted on the surface of the three-dimensional object according to a synthesis coefficient acquired by the mapping unit. An image processing program for causing a computer to paste a texture image on a three-dimensional object composed of a plurality of surfaces,
Computer
Predetermined direction projection mapping means for projecting and mapping a texture image from a predetermined direction on the three-dimensional object;
An environment map image acquisition unit configured to acquire an environment map image configured by a plurality of pixels, in which a combination coefficient used for combining a plurality of texture images is set for each pixel;
Based on the environment mapping process for the three-dimensional object using the environment map image acquired by the environment map image acquiring means, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the three-dimensional object is specified. Mapping means for obtaining a synthesis coefficient set for the specified pixel;
Different direction projection mapping means for projecting and mapping a texture image from a direction different from the projection direction of the texture image that has been projection mapped to the three-dimensional object;
According to the synthesis coefficient acquired by the mapping unit, the projection mapped texture image and the texture image that has been projected mapped from the different direction are combined as a synthesis unit,
The computer repeatedly performs the acquisition of the synthesis coefficient by the mapping unit, the projection mapping of the texture image by the different direction projection mapping unit, and the synthesis of the texture image by the synthesis unit. An image processing program characterized by causing a texture image to be pasted. An image processing apparatus that performs processing of pasting a texture image on a solid object composed of a plurality of surfaces,
An environment map image acquisition unit configured to acquire an environment map image configured by a plurality of pixels, in which a combination coefficient used for combining a plurality of texture images is set for each pixel;
Based on the environment mapping process for the three-dimensional object using the environment map image acquired by the environment map image acquiring means, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the three-dimensional object is specified. Mapping means for obtaining a synthesis coefficient set for the specified pixel;
Pasting means for pasting a plurality of texture images to the three-dimensional object;
An image processing apparatus comprising: a combining unit configured to combine a plurality of texture images pasted on the surface of the three-dimensional object according to the combining coefficient acquired by the mapping unit. An image processing apparatus that performs processing of pasting a texture image on a solid object composed of a plurality of surfaces,
Predetermined direction projection mapping means for projecting and mapping a texture image from a predetermined direction on the three-dimensional object;
An environment map image acquisition unit configured to acquire an environment map image configured by a plurality of pixels, in which a combination coefficient used for combining a plurality of texture images is set for each pixel;
Based on the environment mapping process for the three-dimensional object using the environment map image acquired by the environment map image acquiring means, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the three-dimensional object is specified. Mapping means for obtaining a synthesis coefficient set for the specified pixel;
Different direction projection mapping means for projecting and mapping a texture image from a direction different from the projection direction of the texture image that has been projection mapped to the three-dimensional object;
In accordance with a synthesis coefficient acquired by the mapping unit, a synthesis unit that synthesizes the texture image that has been projection mapped and the texture image that has been projection mapped from the different direction;
Obtaining a texture coefficient from a plurality of directions with respect to the solid object by repeatedly obtaining a synthesis coefficient by the mapping means, projecting mapping of a texture image by the different direction projection mapping means, and synthesizing a texture image by the synthesis means. An image processing apparatus comprising: a texture mapping unit to be pasted. An image processing system for performing a process of pasting a texture image on a solid object composed of a plurality of surfaces,
An environment map image acquisition unit configured to acquire an environment map image configured by a plurality of pixels, in which a combination coefficient used for combining a plurality of texture images is set for each pixel;
Based on the environment mapping process for the three-dimensional object using the environment map image acquired by the environment map image acquiring means, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the three-dimensional object is specified. Mapping means for obtaining a synthesis coefficient set for the specified pixel;
Pasting means for pasting a plurality of texture images to the three-dimensional object;
An image processing system comprising: a combining unit configured to combine a plurality of texture images pasted on the surface of the three-dimensional object according to the combining coefficient acquired by the mapping unit. An image processing system for performing a process of pasting a texture image on a solid object composed of a plurality of surfaces,
Predetermined direction projection mapping means for projecting and mapping a texture image from a predetermined direction on the three-dimensional object;
An environment map image acquisition unit configured to acquire an environment map image configured by a plurality of pixels, in which a combination coefficient used for combining a plurality of texture images is set for each pixel;
Based on the environment mapping process for the three-dimensional object using the environment map image acquired by the environment map image acquiring means, the pixel in the environment map image corresponding to each pixel of the texture image pasted on the surface of the three-dimensional object is specified. Mapping means for obtaining a synthesis coefficient set for the specified pixel;
Different direction projection mapping means for projecting and mapping a texture image from a direction different from the projection direction of the texture image that has been projection mapped to the three-dimensional object;
In accordance with a synthesis coefficient acquired by the mapping unit, a synthesis unit that synthesizes the texture image that has been projection mapped and the texture image that has been projection mapped from the different direction;
Obtaining a texture coefficient from a plurality of directions with respect to the solid object by repeatedly obtaining a synthesis coefficient by the mapping means, projecting mapping of a texture image by the different direction projection mapping means, and synthesizing a texture image by the synthesis means. An image processing system comprising: a texture mapping unit to be pasted.