JP3867071B2 - Image processing apparatus and image processing method - Google Patents

Description

  The present invention relates to an image processing technique for generating a reflection image of an object on a plane.

  When a three-dimensional virtual space is used as a game space, various optical expressions have been conventionally performed in the game space.

  For example, there is an optical expression in which an object in a game space is blurred on a plane existing in the same space. Conventionally, such an expression has been realized by a method having a relatively large amount of calculation such as ray tracing. However, the ray tracing process generally has a huge amount of processing, and when real-time (game screen) rendering such as a game is required, there is a problem that the process is not in time for the rendering time.

  The present invention has been made in consideration of such points, and an object thereof is to realize an optical expression such that an object in a game space is blurred on a plane existing in the same space by a relatively simple process. And

  In order to achieve the object of the present invention, for example, an image processing apparatus of the present invention comprises the following arrangement.

That is, when the object in the virtual space and the viewpoint are located on the same side with respect to a predetermined plane, and the viewing direction of the viewpoint is directed to the plane, the object that is visible on the plane and is reflected on the plane An image processing apparatus for generating an image of
When the object is arranged at a position and orientation that is in contrast to the position and orientation of the object with respect to the plane, a straight line passing through the pixel and the viewpoint position intersects the pixel constituting the object with the plane. First projecting means for generating a first projected image by projecting the object onto the plane by projecting to a position to be
First shift means for shifting the position of the image generated by the first projection means by a predetermined amount to one side of the plane and in the normal direction of the surface of the one side of the plane;
By projecting the pixels constituting the image after the shift by the first shift means to a position where a straight line passing through the pixel and the position of the viewpoint intersects the plane, and lowering the α value of the projected pixel Second projecting means for generating an image obtained by projecting the image shifted by the first shifting means onto the plane;
Second shift means for further shifting the position of the previously shifted image after the processing by the second projection means by a predetermined amount in the previous shift direction;
The pixels constituting the image after the shift by the second shift means are projected to a position where a straight line passing through the pixel and the position of the viewpoint intersects the plane, and the α value of the pixel to be projected is shifted before the shift. a third projection unit that generates an image obtained by projecting the image after the shift by the second shift unit onto the plane by lowering the α value.
Further, the first shifting means shifts the position of the image generated by the first projecting means to the other side of the plane and a predetermined amount in the normal direction of the surface on the other side of the plane. In some cases, the second projection unit, the second shift unit, and the third projection unit perform processing.
The respective images projected on the plane by the first projecting unit, the second projecting unit, and the third projecting unit are respectively superimposed and drawn.

  In order to achieve the object of the present invention, for example, an image processing method of the present invention comprises the following arrangement.

That is, when the object in the virtual space and the viewpoint are located on the same side with respect to a predetermined plane, and the viewing direction of the viewpoint is directed to the plane, the object that is visible on the plane and is reflected on the plane An image processing method for generating an image of
When the object is arranged at a position and orientation that is in contrast to the position and orientation of the object with respect to the plane, a straight line passing through the pixel and the viewpoint position intersects the pixel constituting the object with the plane. A first projection step of generating a first projection image by projecting the object onto the plane by projecting to a position to be
A first shift step of shifting the position of the image generated in the first projection step by a predetermined amount to one side of the plane and in the normal direction of the surface of the one side of the plane;
By projecting the pixels constituting the image after the shift in the first shift step to a position where a straight line passing through the pixel and the position of the viewpoint intersects the plane, and lowering the α value of the projected pixel A second projecting step for generating an image obtained by projecting the image after the shifting by the first shifting step onto the plane;
A second shift step of further shifting the position of the previously shifted image after the processing by the second projection step by a predetermined amount in the previous shift direction;
The pixels constituting the image after the shift in the second shift step are projected at a position where a straight line passing through the pixel and the position of the viewpoint intersects the plane, and the α value of the pixel to be projected is shifted before the shift. a third projecting step for generating an image obtained by projecting the image after the shifting by the second shifting step onto the plane by lowering the α value,
Further, in the first shifting step, the position of the image generated in the first projecting step is shifted by a predetermined amount to the other side of the plane and in the normal direction of the other side of the plane. In some cases, the second projection process, the second shift process, and the third projection process are performed.
The respective images projected on the plane in the first projecting step, the second projecting step, and the third projecting step are respectively superimposed and drawn.

  With the configuration of the present invention, an optical expression in which an object in the game space is blurred on a plane existing in the space can be realized by a relatively simple process.

  Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  In this embodiment, when a three-dimensional virtual space is used as a game space, an object having a three-dimensional shape and a viewpoint in the game space are provided in the same space (the term “plane” used here). Is located on the same side with respect to the plane), and when the viewing direction of the viewpoint is directed to this plane, it appears blurred on this plane. Image processing for generating an object image is performed. Hereinafter, the image processing according to the present embodiment will be described in more detail.

  FIG. 1 is a block diagram illustrating a basic configuration of a computer that functions as an image processing apparatus that executes image processing according to the present embodiment.

  A CPU 101 controls the entire apparatus using programs and data stored in the RAM 102 and the ROM 103 and executes the image processing according to the present embodiment.

  Reference numeral 102 denotes a RAM which has an area for temporarily storing programs and data loaded from the external storage device 107 and the storage medium drive device 108 and a work area used by the CPU 101 for executing various processes. .

  Reference numeral 103 denotes a ROM which stores a boot program, data related to the setting of the apparatus, and the like.

  Reference numerals 104 and 105 denote a keyboard and a mouse, which are used for inputting various instructions to the CPU 101. In addition, as a device that can input various instructions to the CPU 101, other devices such as a joystick and a game pad can be used.

  A display unit 106 includes a CRT, a liquid crystal screen, and the like, and can display processing results by the CPU 101 by information such as images and characters.

  Reference numeral 107 denotes an external storage device which functions as a large-capacity information storage device such as a hard disk drive device. Here, an OS (operating system) or a program for causing the CPU 101 to execute image processing according to this embodiment to be described later. Data, object data in the virtual space (if the object is represented by a polygon, each vertex coordinate position of each polygon constituting the object, data indicating the normal vector of each polygon, and When mapping a texture, this texture data, etc., or the above plane data (if the plane is represented by a polygon, each vertex coordinate position of each polygon constituting this plane, each polygon Data indicating the normal vector of and the plane When mapping a texture, the texture data, etc.) and the like are stored, it is under the control of the CPU 101, are read out to the RAM102, if necessary.

  Reference numeral 108 denotes a storage medium drive device that reads out programs and data recorded on a storage medium such as a CD-ROM or DVD-ROM and outputs them to the RAM 102 or the external storage device 107. Note that a program or data for causing the CPU 101 to execute image processing according to the present embodiment, which will be described later, data of an object in the virtual space, or data of the plane may be recorded in this storage medium. These programs and data are read from the storage medium by the storage medium drive device 108 under the control of the CPU 101 and output to the RAM 102. If the storage medium is a writable medium such as a CD-R or a DVD-RAM, the storage medium drive device 108 performs a process of writing a program and data to the storage medium under the control of the CPU 101.

  Reference numeral 109 denotes a bus connecting the above-described units.

  Next, image processing according to this embodiment performed by a computer having the above configuration will be described. FIG. 2A is a diagram for explaining the image processing according to the present embodiment, that is, an image in which the object 202 is reflected on the plane 203 that is visible according to the position from the viewpoint 201 is generated on the plane 203. It is a figure for demonstrating a process.

  In the figure, 201 is a viewpoint of a player or the like, and in the following, generation of “an image of the object 202 reflected on the plane 203” that can be seen from the viewpoint 201 according to its position will be described. Faces the plane 203.

  Reference numeral 202 denotes an object having a three-dimensional shape in the game space, and is composed of a set of pixels having a three-dimensional coordinate position. The expression method of the object 202 is not particularly limited. For example, a combination of a plurality of polygons to express the shape of the object 202 and a texture image mapped on the polygons may be used.

  The arrangement position of the object 202 is provided on the same side as the position of the viewpoint 201 with respect to the plane 203. In this embodiment, in order to simplify the description, the shape of the object 202 is a spherical shape, but it will be apparent from the following description that it may be an arbitrary shape.

203 is a plane provided in the game space, and as described above, the term “plane” includes those with irregularities on each part of the plane. 204 is a mirror image of the plane 202 of the object 202 described later. It is an object.

  Based on the above settings, a process for generating an image of the object 202 reflected on the plane 203 that can be seen from the viewpoint 201 according to the position (hereinafter, a reflected image) will be described. The reflected image has a brightest part area and a part where the brightness gradually disappears thereafter. In the following, the creation process of the brightest part and the part where the brightness gradually disappears will be described.

  First, generation processing of an image of the brightest part in the reflected image will be described.

  First, the same object (mirror image object 204) as the object 202 is placed on the plane 203 at a position and orientation that is in contrast to the position and orientation of the object 202. The mirror image object 204 is provided for the sake of convenience for the following processing, and is not displayed on the display unit 106.

  In the present embodiment, since the object 202 has a spherical shape, the object 202 and the mirror image object 204 appear to have the same posture in the drawing, but for example, an object 210 as shown in FIG. , The mirror image object has a posture that is in contrast to the object 210 with respect to the plane 203 as indicated by 211.

  Returning to FIG. 2A, the brightest part of the reflected image is the point on the mirror image object 204 (as described above, the object 202 is composed of a set of pixels having a three-dimensional coordinate position. The mirror image object 204 that is the mirror image is also composed of a set of pixels having a three-dimensional coordinate position, and thus “each point” on the mirror image object 204 means “each pixel” constituting the mirror image object 204. ) And the position of the viewpoint 201 is constituted by a set of points intersecting the plane 203.

  FIG. 3 is a diagram for explaining a method for generating an image of the brightest part of the reflected image. For example, a point A on the mirror image object 204 has a plane 203 connecting a straight line connecting the position of the point A and the position of the viewpoint 201. And a point B on the mirror image object 204 is projected onto a point B ′ at a position where a straight line connecting the position of the point B and the position of the viewpoint 201 intersects the plane 203. Therefore, since the pixel at the position of the point A is projected at the position of A ′ and the pixel at the position of the point B is projected at the position of B ′, this processing is performed for each point on the mirror image object 204. A projected image of the mirror image object 204 on the plane 203 that can be seen from the position of the viewpoint 201 can be drawn on the plane 203. In FIG. 2A, the range of this projection image drawn on the plane 203 is one-dimensionally represented by R.

  Even if each point on the mirror image object 204 is projected onto the plane 203, there is a blank portion where no pixel exists between the projected pixels. Therefore, this blank part is interpolated by calculating the average value of the pixels adjacent to the blank part, or the internal value of the value of the pixel adjacent to the blank part depending on the position of the pixel in the blank. The pixel value is filled by some interpolation method, such as calculating and interpolating.

  In this way, a projection image can be obtained, and this projection image is referred to as “the image of the brightest part of the reflected image” (hereinafter referred to as the first projection image). In addition, although it is about the process which projects each point on the mirror image object 204 on the plane 203, generally such a process is performed by matrix transformation, Comprising: Each pixel which comprises the mirror image object 204 is planar. This is performed using a matrix for projecting onto 203.

  FIG. 4 is a diagram showing how the mirror image object 204 seen when an arbitrary position on the plane 203 is viewed from the position of the viewpoint 201 and the first projection image, and 402 is a first view for the mirror image object 204. It is a projection image. By the above projection processing, the first projection image 402 extends in the line-of-sight direction of the viewpoint 201 in the plane 203 rather than the appearance of the mirror image object 204 shown in FIG.

  Next, a method for generating an image of a portion of the reflected image that is slightly less bright than the first projected image will be described. The first projection image generated by the above process is generated on the plane 203. Therefore, a process of shifting the position of this image by a predetermined amount in the normal direction of the surface of the plane 203 on the position of the viewpoint 201 is performed. FIG. 5 is a diagram for explaining this shift process. By performing the shift process, the first projection image is given a predetermined amount in the normal direction of the surface of the plane 203 on the position of the viewpoint 201 (d in FIG. 5). ) A shifted image 501 (hereinafter referred to as a second image) can be obtained.

  Then, the second image 501 is projected onto the plane 203 in the same manner as when generating the first projection image. FIG. 6 is a diagram for explaining the process of projecting the second image onto the plane 203. Reference numeral 601 denotes a second image, and a pixel C on the second image 601 is projected onto a position C ′ where a straight line connecting the position of the pixel C and the position of the viewpoint 201 intersects the plane 203, The pixel D on the image 601 projects to a position C ′ where a straight line connecting the position of the pixel D and the position of the viewpoint 201 intersects the plane 203.

  By performing such processing for each pixel constituting the second image 601, the position is shifted in the forward direction of the line of sight indicated by the arrow in the figure relative to the first projection image and extended in that direction (the first projection The relationship between the region R of the image and the second projection image R ′ described below) image (hereinafter referred to as the second projection image) can be obtained.

  Note that the second projection image has a blank portion where no pixels exist between the pixels constituting the second projection image only by the above processing. Therefore, this blank part is interpolated by calculating the average value of the pixels adjacent to the blank part, or the internal value of the value of the pixel adjacent to the blank part depending on the position of the pixel in the blank. The pixel value is filled by some interpolation method, such as calculating and interpolating.

  Furthermore, a process of slightly lowering the α value for each pixel constituting the second projection image than that of the first projection image is performed. Thereby, since the transparency of the second projection image is slightly higher than that of the first projection image, the brightness of the image is also smaller than that of the first projection image.

  The second projection image created by the above processing is drawn in the area on the projected plane 203, and as a result, it is superimposed on the first projection image drawn on the plane 203 previously. Become.

  Next, an image of a part of the reflected image that is slightly less bright than the second projection image is generated. The generation process is basically the same as the generation process of the second projection image. is there. That is, the position of the second image is shifted by a predetermined amount in the previous shift direction (the normal direction of the surface of the plane 203 on the position of the viewpoint 201) to obtain the third image. This shift amount may be the same as the previous one or may be different.

  Then, a process of projecting the third image onto the plane 203 is performed in the same manner as when generating the second projection image. FIG. 7 is a diagram for explaining the process of projecting the third image onto the plane 203 to obtain the third projection image.

  Reference numeral 701 denotes a third image, and a pixel E on the third image 701 is projected to a position E ′ where a straight line connecting the position of the pixel E and the position of the viewpoint 201 intersects the plane 203. The pixel F on the image 701 projects a straight line connecting the position of the pixel F and the position of the viewpoint 201 to a position F ′ where the plane 203 intersects.

  By performing such processing for each pixel constituting the third image 701, the position is shifted in the forward direction of the line of sight indicated by the arrow in the figure relative to the second projected image, and the image (third Projection image) can be obtained.

  Note that the third projection image has a blank portion where no pixel exists between the pixels constituting the third projection image only by the above processing. Therefore, this blank part is interpolated by calculating the average value of the pixels adjacent to the blank part, or the internal value of the value of the pixel adjacent to the blank part depending on the position of the pixel in the blank. The pixel value is filled by some interpolation method, such as calculating and interpolating.

  Further, a process of slightly lowering the α value for each pixel constituting the third projection image as compared with the second projection image is performed. As a result, the third projected image is slightly more transparent than the second projected image, so the brightness of the image is also smaller than that of the second projected image.

  The third projection image created by the above processing is drawn in the area on the projected plane 203, and as a result, on the first projection image and the second projection image drawn on the plane 203 previously. It will be superimposed on.

  In this way, the position of the previously shifted image is further shifted in the previously shifted direction, the shifted image is projected onto the plane 203, and the projected image is superimposed on the previously created image. Is repeated a limited number of times (number of times within the range in which the vertical height of the image after the shift from the plane 203 is equal to or less than the vertical height of the viewpoint 201 from the plane 203). An image whose brightness gradually disappears toward the front can be drawn on the plane 203.

  Such an image is shown in FIG. This figure shows a superimposed image of the first projection image, the second projection image, and the third projection image, where 801 is the first projection image, 802 is the second projection image, and 803 is the third projection image. The projection image of is shown. As described above, the center position of the second projection image is shifted in the forward direction of the line of sight relative to the first projection image (the center position when the first and second projection images are regarded as an ellipse). The center position of the third projection image is shifted in the forward direction of the line of sight relative to the second projection image (the center position when the second and third projection images are regarded as an ellipse). In addition, it becomes something that extends in that direction. Thereby, the brightness gradually decreases in the forward direction of the line of sight, and an image extending in that direction can be generated. In addition, the amount of deviation and extension of the center becomes larger as the position of the viewpoint 201 is closer to the plane 203, and it is an expression that does not give a phenomenon unnaturalness compared to the case of viewing an actual reflected image. It becomes.

  In addition, when the processing speed of the computer is faster, by reducing the shift amount and increasing the number of shifts, it is possible to more smoothly express how the brightness fades. A suitable expression can be realized.

  Note that the same processing as the above processing is performed by shifting the first projection image by a predetermined amount in the normal direction of the plane 203 opposite to the position of the viewpoint 201 (hereinafter, this shift is referred to as “negative shift”). (Referred to as the case). That is, the image 203 is shifted in the normal direction of the surface opposite to the position of the viewpoint 201 with respect to the plane 203, the shifted image is projected onto the plane 203, and the image after projection is created so far. A process of repeating the process of superimposing on a finite number of times is performed. This is the same as the processing described above except that the shift direction is opposite to the plane 203. FIG. 9 is a diagram for explaining a negative shift.

  Note that the shift amount and the number of shifts may be the same or different on each side with respect to the plane 203. Each projection image generated by performing the shift, projection, and superimposing processes on both sides of the plane 203 is superimposed and recorded on the plane 203. As a result, FIG. As shown, in addition to the parts 801 to 803, a part 1002 (the part of the image projected on the plane 203 by shifting the first projection image by a negative shift), and then the bright part 1003 (by the negative shift) The first projection image is shifted twice, and an image in which the portion of the image projected on the plane 203 is superimposed is obtained. FIG. 10 is a diagram illustrating a superimposed image in which projection images are generated on both sides of the plane 203.

  Note that the image shown in the figure is for the case where the number of shifts is 3 on each side of the plane 203, and the number of levels of brightness gradation is different only in cases where the number of shifts is other than this. The rest is basically the same.

  FIG. 11 is a flowchart of the image processing according to the present embodiment described above. Note that the program according to the flowchart of FIG. 10 is loaded from the external storage device 107 into the RAM 102 or from the storage medium by the storage medium drive device 108, and the CPU 101 executes this so that the computer according to the present embodiment The image processing according to the present embodiment described above is executed. Naturally, it is assumed that data relating to objects, viewpoints, and planes used for image processing are loaded in the RAM 102 in the same manner.

  First, a variable n to be used below is initialized to 2 (step S1101). Next, the mirror image object 204, which is the same object as the object 202, is placed on the plane 203 at a position and orientation that is in contrast to the position and orientation of the object 202 (step S1102). Then, the mirror image object 204 is projected onto the plane 203 by the above-described processing, and a first projection image, which is an image obtained by performing a blank portion interpolation process on the projected image, is generated (step S1103). In other words, the generation of the first projection image here means that the first projection image is drawn in a region where the mirror image object 204 is projected on the plane 203.

  Next, a process of shifting the position of the first projection image by a predetermined amount in the normal direction of one surface of the plane 203 is performed (step S1104). Here, although the position of the first projection image is shifted, the first projection image drawn on the plane 203 remains as it is. The image after the shift becomes the nth image. Then, a process of projecting the n-th image onto the plane 203 is performed (step S1105), and further, a blank portion interpolation process and a process of lowering the α value are performed on the projected image, and the projected image on the plane 203 is projected. The nth projection image is drawn (step S1106). In addition, it superimposes on the said 1st projection image by this drawing.

  Then, a process of shifting the position of the nth image by a predetermined amount in the conventional shift direction is performed (step S1107). The image after the shift is the (n + 1) th image. Then, 1 is added to the value held by the variable n (step S1108), and it is determined whether or not the value held by the variable n after the addition has reached a predetermined value N (step S1109). If n <N, the process returns to step S1105, and the process is repeated thereafter.

  On the other hand, if n = N, the process advances to step S1110 to determine whether or not the shift process has been performed on the other side of the plane 203 (step S1110). If not, the process proceeds to step S1111, the shift direction is reversed (step S1111), the variable n is initialized to 2 (step S1112), and the processes after step S1104 are performed on the other side with respect to the plane 203. The process is assumed to shift in the normal direction.

  With the above processing, an image in which an object appears blurred on a plane that can be seen from the viewpoint in the game space according to the position by a method that is relatively easy for a computer, such as projection calculation processing, shift processing, and superimposition processing. Can be generated and drawn on this plane.

  In particular, when generating an image of an object that appears on a water surface that is a wave, if a wave texture is pasted on the plane 203 so as to have a transparent region, the above processing is performed on the transparent portion. Thus, a blurred reflection image of the object can be seen and a suitable expression can be made. Therefore, the image processing according to the present embodiment is a suitable method for generating an image of an object that appears on the water surface that is a wave.

  In the present embodiment, the object has a three-dimensional shape, but may have a two-dimensional shape, that is, a single image. That is, the image processing according to the present embodiment described above can be applied by arranging a single image in the game space and giving three-dimensional coordinates to each pixel constituting the single image.

  Further, the above processing (for example, processing according to part or all of the flowchart shown in FIG. 11) is stored as a program in a storage medium such as a CD-R, ROM, DVD-ROM, MO, game cartridge, etc. The program stored in the storage medium is read (installed or copied) into the computer, and the computer or the CPU of the computer executes the program, whereby the computer can realize the above processing. Therefore, since the storage medium storing this program also enables the present invention, it is obvious that this storage medium is also within the scope of the present invention.

  In addition, the server apparatus holds a program for the above processing (for example, processing in accordance with part or all of the flowchart shown in FIG. 11), and supplies these to the computer via a network by a well-known technique. Can do. Since the CPU or MPU of the computer supplied with these programs and data can be used to realize the above processing, this server device can also be interpreted as the storage medium. Obviously, it is within the scope of the present invention.

  The storage medium may be other than a program or data provided to the computer from the outside, may be a memory chip incorporated in the computer, and the definition of the storage medium should be interpreted more widely. It is.

1 is a block diagram illustrating a basic configuration of a computer that functions as an image processing apparatus that executes image processing according to an embodiment of the present invention. (A) is a figure for demonstrating the image processing which concerns on this embodiment, (b) is a figure for demonstrating the mirror image object in case an object is not spherical. It is a figure explaining the production | generation method of the image of the brightest part among reflected images. It is a figure showing how the mirror image object 204 seen when seeing the arbitrary positions on the plane 203 from the position of the viewpoint 201, and the 1st projection image. It is a figure explaining a shift process. It is a figure explaining the process which projects a 2nd image on the plane 203. FIG. It is a figure explaining the process which projects a 3rd image on the plane 203, and obtains a 3rd projection image. It is a figure which shows the superimposed image of a 1st projection image, a 2nd projection image, and a 3rd projection image. It is a figure explaining a negative shift. It is a figure which shows the image which produced | generated the projection image on both sides of the plane 203, and was superimposed. 3 is a flowchart of image processing according to an embodiment of the present invention.

Claims (8)

An image of the object on the plane that is visible on the plane when the object and the viewpoint in the virtual space are located on the same side with respect to a predetermined plane and the viewing direction of the viewpoint is directed to the plane An image processing device for generating
When the object is arranged at a position and orientation that is in contrast to the position and orientation of the object with respect to the plane, a straight line passing through the pixel and the viewpoint position intersects the pixel constituting the object with the plane. First projecting means for generating a first projected image by projecting the object onto the plane by projecting to a position to be
First shift means for shifting the position of the image generated by the first projection means by a predetermined amount to one side of the plane and in the normal direction of the surface of the one side of the plane;
By projecting the pixels constituting the image after the shift by the first shift means to a position where a straight line passing through the pixel and the position of the viewpoint intersects the plane, and lowering the α value of the projected pixel Second projecting means for generating an image obtained by projecting the image shifted by the first shifting means onto the plane;
Second shift means for further shifting the position of the previously shifted image after the processing by the second projection means by a predetermined amount in the previous shift direction;
The pixels constituting the image after the shift by the second shift means are projected to a position where a straight line passing through the pixel and the position of the viewpoint intersects the plane, and the α value of the pixel to be projected is shifted before the shift. a third projection unit that generates an image obtained by projecting the image after the shift by the second shift unit onto the plane by lowering the α value.
Further, the first shifting means shifts the position of the image generated by the first projecting means to the other side of the plane and a predetermined amount in the normal direction of the surface on the other side of the plane. In some cases, the second projection unit, the second shift unit, and the third projection unit perform processing.
An image processing apparatus, wherein each image projected on the plane by the first projecting unit, the second projecting unit, and the third projecting unit is superimposed and drawn. An image of the object on the plane that is visible on the plane when the object and the viewpoint in the virtual space are located on the same side with respect to a predetermined plane and the viewing direction of the viewpoint is directed to the plane An image processing method for generating
When the object is arranged at a position and orientation that is in contrast to the position and orientation of the object with respect to the plane, a straight line passing through the pixel and the viewpoint position intersects the pixel constituting the object with the plane. A first projection step of generating a first projection image by projecting the object onto the plane by projecting to a position to be
A first shift step of shifting the position of the image generated in the first projection step by a predetermined amount to one side of the plane and in the normal direction of the surface of the one side of the plane;
By projecting the pixels constituting the image after the shift in the first shift step to a position where a straight line passing through the pixel and the position of the viewpoint intersects the plane, and lowering the α value of the projected pixel A second projecting step for generating an image obtained by projecting the image after the shifting by the first shifting step onto the plane;
A second shift step of further shifting the position of the previously shifted image after the processing by the second projection step by a predetermined amount in the previous shift direction;
The pixels constituting the image after the shift in the second shift step are projected at a position where a straight line passing through the pixel and the position of the viewpoint intersects the plane, and the α value of the pixel to be projected is shifted before the shift. a third projecting step for generating an image obtained by projecting the image after the shifting by the second shifting step onto the plane by lowering the α value,
Further, in the first shifting step, the position of the image generated in the first projecting step is shifted by a predetermined amount to the other side of the plane and in the normal direction of the other side of the plane. In some cases, the second projection process, the second shift process, and the third projection process are performed.
An image processing method, wherein each image projected on the plane in the first projecting step, the second projecting step, and the third projecting step is drawn in a superimposed manner. 3. The method according to claim 2, further comprising an interpolation step of interpolating between pixels constituting an image projected on the plane by the first projection step, the second projection step, and the third projection step. The image processing method as described. In the first shift step, when shifting the position of the image generated in the first projection step to the same side as the position of the viewpoint with respect to the plane,
The shift process is performed in the second shift step so that a vertical height of the image after the shift from the plane does not exceed a vertical height from the plane to the position of the viewpoint. 3. The image processing method according to 2. The image processing method according to claim 2, wherein the processing by the second shift step and the third projection step is repeated a predetermined number of times. The image processing method according to claim 2, wherein the object is an object having a three-dimensional shape in the virtual space. The image processing method according to claim 2, wherein the object is a single image drawn on a two-dimensional plane in the virtual space. A program that causes a computer to execute the image processing method according to any one of claims 2 to 7.

Images