JPH09265548A - Method and device for generating pattern simulatively representing wrinkle, and printed matter having the same pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To generate the pattern which simulatively represents wrinkles by using a computer. SOLUTION: Various parameters which are needed for a process are inputted (S41) and a group of regular triangles filling a plane is generated on the XY plane (S42). Coordinate values of a UV coordinate system in which a texture image is taken are assigned to the respective vertexes An of the regular triangle group (S43). The respective vertexes An are displaced in three dimensions at random with random numbers and a wrinkled plane is formed of the deformed triangles (S44 and S45). For the wrinkled plane, luminance calculation is performed in consideration of a given assumed light source to find luminance at each part (S46). The texture image is inputted to the UV coordinate system (S47) and texture mapping considering the luminance is performed (S48) by using the texture coordinate values (u, v) of the respective vertexes An on the wrinkled plane as a clue. The wrinkled plane after the texture is mapped is projected on the XY plane to obtain and print two-dimensional image data (S49).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed material having a pattern in which pseudo wrinkles are expressed, and a generation method and a generation device for generating such a pattern using a computer.

[0002]

2. Description of the Related Art In addition to printing on paper products such as leaflets and catalogs, printing on the surface of building materials such as wallboards and doors, printing on decorative boards that make up the surface of furniture, etc. Printed materials are widely used in all fields. In particular, in the design of building materials and the like, it is becoming an important issue to design a pattern that always gives a novel image, and industrial designers are focusing on creating unique patterns. In recent years, a computer-aided graphic design method has been established, and it has become possible to relatively easily generate a novel pattern using a computer, which was impossible by hand drawing. . In addition, the technique of generating an image with a completely new image by applying various effects to the original digital image has become widespread, and various application software for graphic design is commercially available. Has reached the end.

[0003]

As described above, due to the spread of graphic design utilizing computers,
Patterns with innovative images are being created one after another, but the more these consumers see these patterns, the sooner they become obsolete. Therefore, there is always a demand for a method of generating a strange pattern by a completely new method.

An object of the present invention is to provide a novel pattern generation method which can be generated relatively easily using a computer.

[0005]

The inventor of the present application has established a method for expressing pseudo wrinkles on a flat printed matter. The point of the present invention is that a pseudo pattern of wrinkles is generated by using this method. Up to now, in order to express wrinkles as a flat pattern, there has been no choice but to adopt a method of actually printing a predetermined pattern on a paper or the like and taking a photo with the paper crumpled. On the other hand, in the method according to the present invention, a pseudo wrinkle expression can be given by inputting a normal wrinkle-free pattern to a computer and then digitally processing the pattern.

The basic principle of the present invention is that wrinkles are represented by polygons. That is, a large number of polygons are arranged and defined so that no gaps are formed on the printing surface on which a predetermined picture is represented. Examples of polygons that can fill the plane include triangles, quadrangles, and hexagons. Among them, it is most efficient to use triangles. For example, if equilateral triangles are used, it is possible to easily define an array of equilateral triangles that fills the plane. Of course, a plurality of types of polygons may be mixed, such as a combination of pentagons and hexagons. Here, for each of these polygons, a random brightness value is defined, and if a part of the pattern is represented in each polygon in a manner corresponding to each brightness value, each polygon Three-dimensional shading information is added to each item, making it possible to express wrinkles in a pseudo manner. Alternatively, if a part of the pattern is expressed in each polygon in a unique deformation mode, the deformation mode of the pattern is different between adjacent polygons, and thus the presence of wrinkles is visually recognized. It becomes possible to make them recognize.
Hereinafter, the present invention will be described for each mode.

(1) A first aspect of the present invention is a method of generating a pattern in which pseudo wrinkles are expressed, in which a pattern is expressed by arranging pixels having unique pixel values on an image plane. Prepared image data, define a number of polygons on a predetermined reference plane side by side so that no gaps are created, and move each vertex of the polygon on the reference plane randomly in three-dimensional space. By doing so, each polygon is randomly deformed, and a wrinkled surface is formed as a set of included surfaces of each polygon after deformation, and a light source is assumed at a predetermined position in three-dimensional space, and the wrinkled surface is At each position of, defining a brightness value according to the shadow caused by the light source,
By projecting the wrinkled surface onto a predetermined projection surface, defining the brightness value corresponding to the corresponding portion on the wrinkled surface at each position on this projection surface, and the pixels on the image plane and the projection surface. By associating each pixel on the image plane with a brightness value, and correcting the pixel value of the pixel on the image plane based on the associated brightness value. The step and the step of generating a pattern from a set of pixels having the corrected pixel value are performed.

(2) A second aspect of the present invention is a method for generating a pattern in which pseudo wrinkles are expressed, in which a pattern is expressed by arranging pixels having unique pixel values on an image plane. The step of preparing the image data, the step of defining a number of polygons on a predetermined reference plane side by side so as not to create a gap, and the image plane and the reference plane are associated
The step of defining a reference point corresponding to each vertex of the polygon on the reference plane on the image plane, and defining the reference polygon with this reference point as the vertex, and the three-dimensional calculation of each vertex of the polygon on the reference plane. Randomly moving in space to deform each polygon at random, forming a wrinkled surface as a set of inclusion surfaces of each polygon after deformation, and a deformed polygon forming a wrinkled surface. Correlating the reference polygons on the image plane with each other, and based on this correspondence, associating pixels on the image plane with each position on the wrinkled surface, and projecting the wrinkled surface onto a predetermined projection surface. Thus, the step of associating each pixel on the image plane with each position on the projection surface and the step of generating a pattern by a set of pixels associated with each other on the projection surface are performed.

(3) A third aspect of the present invention is the above-mentioned second aspect.
In the generation method according to the aspect, a light source is assumed at a predetermined position in the three-dimensional space, and at each position of the wrinkled surface, a step of defining a brightness value according to a shadow generated based on the light source, and an image plane The step of associating the brightness value corresponding to each pixel to each pixel and the step of correcting the pixel value of the pixel on the image plane based on the brightness value respectively associated with the pixel are further added, and The pattern is generated by a set of pixels having pixel values.

(4) A fourth aspect of the present invention relates to the above-mentioned first aspect.
In the generation method according to the third aspect, an equilateral triangle having a dimension D on one side is used as the polygon defined on the reference plane, and when the vertices are randomly moved, the maximum value of the movement amount is D / 2.
It is set so that

(5) A fifth aspect of the present invention is the above-mentioned first aspect.
In the generation method according to any one of the above aspects 4 to 4, the pixels having a specific positional relationship on the contour are substantially the same so that a continuous tone can be obtained even when a plurality of the same patterns are prepared and adjacently arranged. When preparing image data having a value and randomly moving the vertices on the reference plane, the vertices on the contour having the above-mentioned specific positional relationship are moved in substantially the same manner, The pattern generated based on the pattern is spatially repeatedly arranged.

(6) A sixth aspect of the present invention is, in an apparatus for generating a pattern in which pseudo wrinkles are expressed, a parameter input means for inputting predetermined parameters, and a random number generation means for generating random numbers. , Image data inputting means for inputting image data showing a predetermined texture image on a predetermined image plane, and a plurality of polygons are arranged side by side on a predetermined reference plane so as not to create a gap based on the input parameters. The polygon defining means to be associated with the image plane and the reference plane,
A reference point corresponding to each vertex of the polygon on the reference plane is defined on the texture image, and texture coordinate assigning means for defining a reference polygon having the reference point as the vertex and each vertex of the polygon on the reference plane. Is randomly moved in a three-dimensional space based on the input parameters to randomly deform each polygon and form a wrinkled surface as a set of inclusion surfaces of each polygon after deformation. And, assuming a light source at a predetermined position in the three-dimensional space, at each position of the wrinkled surface, a shadow calculation means for calculating the brightness according to the shadow generated based on the light source, and a deformed polygon forming the wrinkled surface. And the reference polygon on the texture image are associated with each other, based on this correspondence, the texture image is mapped to each position on the wrinkled surface in consideration of the brightness, and the mapped texture image is projected onto a predetermined projection surface. Is provided with a, a texture mapping means for outputting a two-dimensional image data by.

(7) A seventh aspect of the present invention relates to the above-mentioned first aspect.
The printed matter is obtained by printing the pattern generated by the generating method according to the fifth aspect.

(8) According to an eighth aspect of the present invention, in a printed matter on which a pattern based on a predetermined picture pattern is printed, a large number of polygons arranged so as not to create a gap on the printing surface are defined. Random brightness values are defined for each polygon, and a part of the picture pattern corresponding to the position of the polygon is expressed in each polygon in a manner according to each brightness value.

(9) According to a ninth aspect of the present invention, in a printed matter on which a pattern based on a predetermined picture is printed, a large number of polygons arranged so as not to create a gap on the printing surface are defined, and In the polygon, a part of the picture pattern corresponding to the position of the polygon is expressed in a unique modification.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

<First Embodiment> FIG. 1 shows a first embodiment of the present invention.
6 is a flowchart showing a procedure of a pattern generation method according to the embodiment. In the first embodiment, a random brightness value is defined for each polygon, and a part of the pattern is represented in each polygon in a manner corresponding to each brightness value.

First, in step S11, image data for a pattern that is the basis of a pattern is prepared. The image data prepared in this embodiment is raster image data configured by arranging pixels having unique pixel values on the image plane. Any form of image data such as vector image data may be used as long as the form is such that the value can be specified. here,
As shown in FIG. 2, an image plane is defined on the UV coordinate plane, the position of an arbitrary pixel Pn is represented by the coordinate value (u, v), and a predetermined pixel value G for this pixel Pn.
It is assumed that n is defined. In the case of a monochrome picture, the pixel value Gn shows a predetermined gradation value, and in the case of a color picture, the pixel value Gn shows the density value of each color component of RGB three primary color system or CMY three primary color system.

In step S12, a polygon is defined on a predetermined reference plane. At this time, it is necessary to define a large number of polygons side by side so as not to create a gap. In other words, a large number of polygons are defined so as to fill the reference plane. Polygons that can fill a two-dimensional plane include triangles, quadrangles, and hexagons. In this embodiment, use of triangles that is the easiest to handle and that can reduce the burden of subsequent calculations. To As the triangle, an isosceles triangle, an isosceles triangle, or the like can be used, but the simplest equilateral triangle is used here. FIG. 3 shows a state in which a reference plane is defined on the XY coordinate plane and a large number of equilateral triangles are defined on the reference plane. Defining an array of equilateral triangles that fills the plane in this way is equivalent to defining a group of vertices arranged at a predetermined pitch. In particular,
Coordinate values (x, y) of each vertex An on the XY coordinate plane
, The interconnections of the individual vertices will be defined. The size of the polygon defined in step S12 is preferably set sufficiently larger than the size of the pixel Pn. In the present invention, since one constituent surface of the wrinkle is represented by this one polygon, a minute polygon which cannot be recognized as the constituent surface of the wrinkle when observed with the naked eye is not preferable.

In the next step S13, the vertices of the polygon on the reference plane are randomly moved in the three-dimensional space to randomly deform each polygon.
A process for forming a wrinkled surface as a set of the inclusion surfaces of each polygon after deformation is performed. That is, a process of moving the individual vertices An defined as shown in FIG. 3 at random in the XYZ three-dimensional space is performed. Although the moving direction may be set at random, it is necessary to set a predetermined upper limit value for the moving amount. In this embodiment, an equilateral triangle having a dimension D on one side is used as a polygon, and when the vertex An is randomly moved, the maximum value of the movement amount is set to D / 2. That is, the amount of movement in the X-axis direction is Δx, the amount of movement in the Y-axis direction is Δy, Z
When the amount of movement in the axial direction is Δz, (Δx ² + Δy
² + Δz ² ) ^1/2 <D / 2, each movement amount Δ
x, Δy, and Δz will be randomly set including signs. In this way, by setting the upper limit of the movement amount to D / 2, it is possible to avoid a situation in which the wrinkled surface S is partially turned upside down, and it is possible to form an ideal wrinkled surface.

By this vertex movement, the coordinate value of each vertex An becomes (x, y, z) having the Z coordinate value. As described above, when each vertex An is randomly moved in the three-dimensional space, each triangle defined by each vertex An after the movement is deformed. How the original equilateral triangle is deformed varies depending on the individual triangle, but many triangles are deformed to scalene triangles. Here, the set of the triangular inclusion surfaces (the surfaces surrounded by the three sides) thus deformed will be referred to as wrinkled surfaces. In step S12, since the triangle is defined so as to fill the plane, this wrinkled surface is always a continuous surface.

FIG. 4 shows the wrinkled surface S thus obtained.
It is a conceptual diagram of. Create a model of such wrinkled surface S,
If this is observed with the naked eye, it will be recognized as a so-called "wrinkled surface". An arbitrary point Qn on the wrinkled surface S has coordinate values (x, y, z) in the XYZ three-dimensional coordinate system. In this embodiment, since a triangle is used as the polygon defined on the reference plane, if a plane is adopted as the inclusion surface (surface having each side as a contour) of the deformed polygon, the The only comprehension surface will be uniquely determined. However, when a quadrangle or a hexagon is used as the polygon, the inner surface of the deformed polygon is usually not a flat surface but a twisted surface. Since such twisted inclusion surface will exist infinitely, in order to define the only wrinkled surface S, the condition indicating which of the infinite inclusion surfaces is adopted (for example, the area is the minimum). It is necessary to determine in advance the condition that the inclusion surface that becomes

In the following step S14, the shadow calculation for the wrinkled surface S is performed. That is, as shown in FIG. 4, the light source L is assumed to be at a predetermined position in the three-dimensional space (in this example, the light source L is a point light source, but a line light source or a surface light source may be used. No), the process of defining the brightness value corresponding to the shadow generated based on this light source at each position of the wrinkled surface S may be performed. Specifically, the reflection condition of the surface of the wrinkled surface S is given as a parameter, and the brightness of each minute surface is calculated in consideration of the normal direction of each minute surface and the irradiation direction of light from the light source L. become. Since various methods are already known as computer graphics technology for such shadow calculation processing, detailed description thereof is omitted here. After all, by this shadow calculation, each point Q on the wrinkled surface S
A predetermined brightness value Kn is defined for each n.

Subsequently, in step S15, the wrinkled surface S is projected onto a predetermined projection surface to define a brightness value corresponding to a corresponding portion on the wrinkled surface S at each position on the projection surface. Perform processing to For example, in the model shown in FIG. 4, if projection is performed with the XY plane as the projection surface,
For an arbitrary point Qn on the wrinkled surface S, a projection point QQn is obtained on the XY plane as shown in FIG.
At this time, the projection point QQn has a corresponding point Qn on the wrinkled surface S.
The luminance value Kn of is given as it is. In this way, if the process of associating the luminance value on the wrinkled surface S with the projection surface is performed, the projection points QQn on this projection surface are XY
The point has a coordinate value (x, y) on the plane and a predetermined luminance value Kn, and a predetermined luminance distribution is obtained on the XY plane. Here, the important point is that the wrinkle image is represented by the brightness distribution thus obtained on the XY plane.

In a succeeding step S16, the brightness value is associated with each pixel on the image plane by associating the pixel on the image plane shown in FIG. 2 with each position on the projection plane shown in FIG. I do. For example, if the pixel Pn on the UV plane positionally corresponds to the projection point QQn on the XY plane, the brightness value Kn of the projection point QQn is associated with this pixel Pn. When there are a plurality of projection points corresponding to the position of the pixel Pn, the representative projection point (for example, the projection point corresponding to the center position of the pixel Pn).
And the brightness value of this representative projection point may be used, or the average of the brightness values of all the projection points that correspond positionally may be used. After all,
In addition to the coordinate value (u, v) and the pixel value Gn, the brightness value Kn is associated with each pixel Pn on the UV image plane.

Therefore, in step S17, this U
The pixel value Gn of the pixel Pn on the V image plane is corrected based on the associated luminance value Kn. For example, when the associated brightness value Kn indicates “brightness higher than the reference”, the pixel value Gn is corrected so that this pixel is displayed brighter, and conversely,
When the associated brightness value Kn indicates “brightness lower than the reference”, the pixel value Gn may be corrected so that this pixel is displayed darker. in short,
By the processing in step S17, the shadow information is added to the image data prepared in step S11.

When the correction of the pixel value is completed in this way, finally, in step S18, a process of generating a pattern as a set of pixels having the corrected pixel value may be performed. Specifically, the work of producing an actual printed matter may be performed based on the image data having the corrected pixel value. The pattern indicated by the image data input in step S11 is represented on the printed matter produced in this manner. Here, a large number of polygons are defined on the printing surface, and a part of the pattern corresponding to the position is expressed in each polygon. Moreover, a random brightness value is defined for each polygon, and a pattern is represented in each polygon in a manner according to each brightness value. Such a pattern on the printed matter will have shadow information based on pseudo wrinkles along with the original pattern information,
The wrinkle feel will be perceived when observed with the naked eye.

<Second Embodiment> FIG. 6 shows a second embodiment of the present invention.
6 is a flowchart showing a procedure of a pattern generation method according to the embodiment. In the second embodiment, a part of the design is expressed in each polygon in a unique modification. In this way, if the shapes of deformation of the adjacent polygons are different from each other, the presence of wrinkles can be visually recognized.

First, in step S21, image data for a pattern that is the basis of a pattern is prepared. This is exactly the same processing as step S11 described above.
As shown in, a large number of pixels Pn having coordinate values (u, v) and pixel values Gn are defined on the UV image plane.

In the following step S22, a polygon is defined on a predetermined reference plane. This process is also the above-mentioned step S
The process is exactly the same as 12. Here, as shown in FIG. 3, it is assumed that a reference plane is defined on the XY coordinate plane and a large number of equilateral triangles are defined on the reference plane. Of course, other polygons may be used instead of the equilateral triangle.

In the next step S23, the UV shown in FIG.
A reference polygon is defined on the image plane. That is, FIG.
3 is associated with the XY reference plane shown in FIG. 3, reference points Rn corresponding to the respective vertices An of the polygon on the XY reference plane are defined on the UV image plane, and the reference points Rn
A process of defining a reference polygon having a vertex as a vertex is performed. FIG. 7 is a diagram showing the reference triangle Tr defined in this way.

Then, in step S24, the wrinkled surface S
To form This process is exactly the same as the above-mentioned step S13. That is, if each of the vertices An of the triangle on the XY reference plane is randomly moved in the three-dimensional space to randomly deform each triangle, the wrinkled surface S is obtained as a set of the inclusion surfaces of each triangle after the deformation. Will be obtained. FIG. 8 shows the wrinkled surface S thus obtained.
It is a figure which shows the upper deformation triangle Td.

In the following step S25, pixels are associated with the wrinkled surface S. That is, first, in FIG.
The deformed triangle Td forming the wrinkled surface S as shown in FIG. 3 and the reference triangle Rn on the UV image plane shown in FIG. 7 are associated with each other. One equilateral triangle on the XY reference plane shown in FIG. 3 is a specific reference triangle Tr on the UV image plane shown in FIG.
And the specific deformed triangle Td shown in FIG. 8 as well. Therefore, each deformed triangle Td on the wrinkled surface S always has a one-to-one correspondence with a specific reference triangle Tr on the UV image plane. Therefore, based on this correspondence, a process of associating each position on the wrinkled surface S with a pixel on the UV image plane is performed. This process is known as a so-called texture mapping process for mapping a two-dimensional texture image onto a three-dimensional surface in the field of computer graphics.

A large number of pixels are arranged on the UV image plane shown in FIG. 7, and a large number of pixels are also included in the reference triangle Tr. The process of step S25 can be conceptually referred to as a process of cutting out the reference triangle Tr including this pixel from the UV image plane and pasting it onto the deformed triangle Td shown in FIG. Of course, since the reference triangle Tr and the modified triangle Td have different sizes and shapes,
When pasting the reference triangle Tr on the deformed triangle Td, a process of distorting the reference triangle Tr by a predetermined method is required. Since such a processing method is known as an existing texture mapping process. The detailed description is omitted here. By performing this texture mapping process on all the deformed triangles forming the wrinkled surface S, the individual pixels Pn defined on the UV image plane are arranged on the wrinkled surface S.

Therefore, in a succeeding step S26, the wrinkled surface S is projected onto a predetermined projection surface so that each position on the projection surface corresponds to each pixel Pn defined on the UV image plane. Perform processing to attach. For example,
In the model shown in FIG. 8, when projection is performed with the XY plane as the projection surface, individual pixels are associated with each other on the XY plane.

Finally, in step S27,
It suffices to perform a process of generating a pattern by a set of pixels associated with each other on the XY projection plane. Specifically, based on the image data made up of pixels associated with the XY projection plane,
It suffices to perform the work of producing an actual printed matter. The pattern shown by the image data input in step S21 is expressed on the printed matter produced in this manner. Here, a large number of polygons are defined on the printing surface, and a part of the pattern corresponding to the position is expressed in each polygon. Moreover, each polygon represents a pattern in a unique modification. For example, in the deformed triangle Td shown in FIG. 8, the pattern in the reference triangle Tr shown in FIG. 7 is deformed and assigned by the texture mapping method, and the final printed matter is placed on the deformed triangle Td. Although the projected image of the mapped pattern is represented, the deformation mode in texture mapping and the projection mode on the printed matter are random for each triangle. In this way, by making different deformation modes (distortion modes) of the patterns between adjacent triangles, it is possible to visually recognize the wrinkle feeling.

<Third Embodiment> FIG. 9 shows a third embodiment of the present invention.
6 is a flowchart showing a procedure of a pattern generation method according to the embodiment. The third embodiment can be said to be a form in which the above-described first embodiment and second embodiment are combined. That is, a part of the pattern is expressed in each polygon in a unique deformation mode, and is expressed based on a unique brightness value, and both the distortion information and the shadow information of the pattern based on wrinkles are expressed. Is meant to be expressed.

First, in step S31, image data for a pattern that is the basis of a pattern is prepared. This is exactly the same processing as steps S11 and S21 described above, and as shown in FIG. 2, a large number of pixels Pn having coordinate values (u, v) and pixel values Gn are defined on the UV image plane. Will be done.

In the following step S32, a polygon is defined on a predetermined reference plane. This process is also the above-mentioned step S
12, the process is exactly the same as S22. Here, as also shown in FIG. 3, it is assumed that a reference plane is defined on the XY coordinate plane and a large number of equilateral triangles are defined on this reference plane. Of course, other polygons may be used instead of the equilateral triangle.

In the next step S33, as shown in FIG. 7, a reference triangle Tr is defined on the UV image plane. This process is also the same as that of step S23 described above.

Then, in step S34, the wrinkled surface S
To form This process also applies to steps S13 and S24 described above.
Is exactly the same as. If each vertex An of the triangle on the XY reference plane is randomly moved in the three-dimensional space to randomly deform each triangle, the wrinkled surface S is obtained as a set of the inclusion surfaces of each triangle after the deformation. Therefore, as shown in FIG. 8, the deformation triangle Td is defined on the wrinkled surface S.

In the following step S35, shadow calculation is performed. This process is exactly the same as the above-mentioned step S14, and as shown in FIG. 4, the light source L is assumed at a predetermined position in the three-dimensional space, and each position of the wrinkled surface S is based on the light source L. The brightness value Kn according to the generated shadow is defined.

The next step S36 is the aforementioned step S36.
The process is exactly the same as 25, and the pixels are associated with the wrinkled surface S. That is, the wrinkled surface S as shown in FIG.
The reference triangle Rr on the UV image plane shown in FIG. 7 is texture-mapped to the deformed triangle Td that forms the pixel Pn defined on the UV image plane.
Will be arranged on the wrinkled surface S.

Subsequently, in step S37, the pixel value is corrected. Due to the above step S36, the wrinkled surface S
A pixel Pn having a predetermined pixel value Gn is arranged on the upper side, and further, a predetermined brightness value Kn is defined at each position of the wrinkled surface S in step S35. Therefore, a process of correcting the pixel value Gn of the pixel Pn based on the brightness value Kn is performed. This correction method is the same as step S17 described above.

Next, in step S38, the wrinkled surface S is projected onto a predetermined projection surface, so that the individual pixels Pn (pixels) defined on the UV image plane at the respective positions on the projection surface. The value is modified). For example, in the model shown in FIG.
When projection is performed using the XY plane as a projection plane, individual pixels are associated with each other on the XY plane.

Finally, in step S27,
It suffices to perform a process of generating a pattern by a set of pixels associated with each other on the XY projection plane. Specifically, based on the image data made up of pixels associated with the XY projection plane,
It suffices to perform the work of producing an actual printed matter. The pattern shown by the image data input in step S21 is expressed on the printed matter produced in this manner. Here, a large number of triangles are defined on this printing surface, and a part of the pattern corresponding to the position is expressed in each triangle. Moreover, each triangle has its own variation,
It means that the pattern is expressed according to the unique brightness value. The important point here is that the deformation of the design and the display brightness are
Each triangle is random, but if one triangle is focused on, it is that the deformation pattern of the pattern and the display brightness are consistent with each other. This is because both the deformation mode of the design and the display brightness are matters determined based on the same wrinkled surface S, and therefore have a physical relationship with each other. In other words, since each part of the pattern is displayed with the display brightness adapted to the three-dimensional deformation mode for forming the wrinkled surface, the texture similar to the actual wrinkle can be recognized. is there. By thus combining the first embodiment and the second embodiment, it is possible to more effectively express wrinkles.

<Other Embodiments> The present invention has been described above with reference to the flow charts based on the three basic embodiments, but the present invention is not limited to these basic embodiments. Besides, the present invention can be implemented in various embodiments. In particular, the steps of the flow charts described so far do not necessarily have to be performed in this order, and the order can be changed as necessary. For example, in the procedure shown in FIG. 9, the shadow calculation process of step S35 and the pixel association process of step S36 may be performed in reverse order. Further, in this procedure, the correction of the pixel value based on the brightness value is performed before the projection, but it may be performed after the projection. In short, finally, based on the correspondence relationship between each position on the wrinkled surface and each pixel on the image plane, each pixel on the image plane is made to correspond to each brightness value, and If the process of correcting the pixel value of each pixel based on the corresponding luminance value is performed, any procedure may be taken.

[0048]

Finally, a preferred embodiment of the present invention will be disclosed.

<Apparatus Configuration for Implementing the Present Invention> FIG.
Reference numeral 0 is a block diagram showing a device configuration used in this embodiment. Here, for convenience of description, different block components are shown for each individual function, but in reality, each of these components is realized by an organic combination of computer hardware and software.

The parameter input means 1 is an apparatus for inputting various parameters used in the processing in other means, and is a parameter for defining a polygon and a random vertex for forming a wrinkled surface. Parameters related to movement, parameters for shadow calculation, etc. are input. The random number generation means 2 is, for example, a device that generates a random number of uniform distribution, and the random number generated here is used when performing a random vertex movement process for forming a wrinkled surface. The image data input means 3 is a device for inputting a pattern to be texture-mapped as digital data, and the image data prepared in steps S11, S21 and S31 described above is input by this device. For example, if an image input device such as a scanner is used, the pattern actually drawn on the paper can be captured as image data. Alternatively, a device that directly captures image data created by another graphic image processing system (a drive that accesses a magnetic or optical recording medium, a data transfer device via a network, or the like) may be used.

The polygon defining means 4 performs a process of defining a number of polygons on a predetermined reference plane side by side so as not to create gaps, based on the predetermined parameters input from the parameter inputting means 1. Specifically, a large number of polygonal arrays are defined by the individual vertex coordinate value data and the data indicating the connection order of each point sequence. When defining an array of equilateral triangles as a polygonal array, the parameter input means 1 may input the length D of one side of the equilateral triangle and the number of equilateral triangles arranged vertically and horizontally as parameters. The ratio of the number of vertical and horizontal arrangements of the equilateral triangle is preferably set so as to match the vertical and horizontal dimension ratio of the pattern input by the image data input means 3 in order to perform efficient processing. That is, as shown in FIG. 7, if the aspect ratio of the pattern (texture) captured on the image plane matches the aspect ratio of the reference triangle array, all the defined triangles are effectively used. Become.

On the other hand, the texture coordinate assigning means 5 associates the image plane with the reference plane, and defines the reference points corresponding to the respective vertices of the polygon on the reference plane on the texture image captured on the image plane. Then, a process for defining a reference polygon having this reference point as a vertex is performed (see FIG. 7). By this processing, each vertex An of the equilateral triangle defined on the reference plane
And each part of the pattern (texture) captured on the UV image plane are associated with each other, and each vertex An has a coordinate value (x, y) in the XY two-dimensional coordinate system and a coordinate value (in the UV two-dimensional coordinate system). u, v) will be assigned. In this embodiment, the UV two-dimensional coordinate system is standardized so that the coordinate values are 0 to 1.

Further, the apex displacement means 6 randomly moves each apex of the polygon defined on the reference plane in the three-dimensional space based on the parameters input from the parameter input means 1. A process of randomly deforming each polygon and forming a wrinkled surface as a set of the inclusion surfaces of each polygon after the deformation is performed. Here, the random numbers generated by the random number generating means 2 are used when the vertices are randomly moved. For example, the movement amount Δx in the X-axis direction, the movement amount Δy in the Y-axis direction, the movement amount Δ in the Z-axis direction.
Each z may be randomly generated based on a random number. However, as described above, when a regular triangle whose one side is D is used as the polygon defined on the reference plane, the condition that (Δx ² + Δy ² + Δz ² ) ^1/2 <D / 2 (that is, It is preferable to impose a condition that the movement distance is less than D / 2).

In order to carry out a movement satisfying these conditions,
It is more suitable to use the rθφ polar coordinate system than to use the XYZ three-dimensional coordinate system. That is, r <D / 2, θ <1
Positions indicated by polar coordinates (r, θ, φ) when the values of r, θ, φ are randomly generated so that 80 °, φ <360 °, and the original vertex position is the origin O. By moving the apex to, it is possible to move the condition described above. It should be noted that if the average value or the variance of the movement amount of each vertex is set as a parameter by the parameter input means 1 and the random movement amount is determined according to this parameter, the generated wrinkled surface It is possible to control the morphology to some extent.

The shadow calculation means 7 assumes a light source at a predetermined position in the three-dimensional space, and executes a shadow calculation process for calculating the brightness corresponding to the shadow generated based on this light source at each position of the wrinkled surface. It is a device. Parameters such as the light source position, the light source form (point light source, line light source, surface light source), the diffuse reflectance, the specular reflectance, and the surface color of the wrinkled surface, which are the conditions for this shadow calculation, are parameter input means. The preset value of 1 will be used. Also, in this embodiment,
The viewpoint position is fixed on the Z axis, and the shadow calculation is performed while the origin O is observed from this viewpoint position. As a technique for calculating such a shadow, one using various reflection models is known in the field of computer graphics.

The texture mapping means 8 associates the deformed polygon forming the wrinkled surface with the reference polygon on the texture image captured by the image data input means 3 on the UV image plane, and establishes the correspondence relationship. Based on this, at each position on the wrinkled surface, the texture image is mapped in consideration of the brightness obtained by the shadow calculation, and the mapped texture image is projected onto a predetermined projection surface to output two-dimensional image data. This is a device that performs processing. Various conditions for performing mapping and projection are determined based on the parameters set by the parameter input means 1. In short, the texture in the reference triangle Tr shown in FIG.
Pixels that are mapped within the modified triangle Td shown in FIG. 8 and that form a texture on the wrinkled surface S are allocated. At this time, since the brightness value Kn obtained by the shadow calculation is taken into consideration, the original pixel value Gn of the pixel Pn forming the texture is corrected by this brightness value Kn.

After all, the corrected pixel value is the original pixel value G
It is a value obtained by blending n and the brightness value Kn. Brightness value Kn
The degree to which is reflected can be set by predetermining the blend ratio of the pixel value Gn and the luminance value Kn as a parameter. If the blending ratio of the pixel value Gn is increased, a pattern in which the texture of the texture (original pattern) is emphasized is generated, and if the blending ratio of the brightness value Kn is increased, the texture of the shadow is emphasized. Pattern will be generated. In this way, when a pixel having a predetermined blended pixel value is defined on the wrinkled surface S, two-dimensional image data is obtained by projecting the pixel on the projection surface.

Thus, based on the two-dimensional image data output from the texture mapping means 8, the printing means 9
Printing plate is performed in the
Printing is performed at 0. Thus, a printed matter having a pattern that artificially expresses wrinkles is obtained.

<Specific Pattern Generation Procedure> Next, a specific pattern generation procedure using the above apparatus will be described with reference to the flowchart of FIG. First, in step S41,
Parameters are input by the parameter input means 1. Specifically, parameters indicating the size of the equilateral triangle, the average value and variance of the displacements of the vertices, the surface characteristics of the wrinkled surface, the light source setting, and the like are set.

In the next step S42, the polygon defining means 4 is operated to generate the vertex coordinate values of the equilateral triangle group and the connecting sequence of the point sequences so as to fill the plane without gaps.
Each vertex An defined here has a coordinate value (x, y) in the XY two-dimensional coordinate system. Subsequent step S
At 43, the normalized coordinate values (u, v) are assigned to all the vertices An as texture coordinates. That is,
By the texture coordinate assigning means 5, as described above,
Coordinate values (u, u in the UV two-dimensional coordinate system) at each vertex An
v) will be assigned and each vertex An will be
It will have coordinate values (x, y, u, v). In this embodiment, as described above, since the coordinate values of the UV two-dimensional coordinate system are standardized to be values of 0 to 1,
0 ≦ u and v ≦ 1.

In the following step S44, the random number generating means 2
A process of three-dimensionally displacing the spatial coordinate value of one vertex An is performed by using the random number generated in 1. and the parameter set by the parameter input means 1. This processing is as already described as the processing of the vertex displacement means 6. Such vertex displacement processing is performed for all the vertices through step S45. By this processing, the Z coordinate value is assigned to each vertex An, and the X coordinate value and the Y coordinate value are also corrected by the displacement. That is, the original vertex An defined on the reference plane had the coordinate value (x, y), but the vertex An after the texture coordinate assignment processing and the displacement processing has the coordinate value (x ′, y ′). ，
z, u, v) (x ′, y ′ are X coordinate values and Y coordinate values after displacement). Thus, the wrinkled surface S is formed in the XYZ three-dimensional coordinate space.

In step S46, brightness calculation is performed on the formed wrinkled surface S using the surface characteristics and the light source setting designated by the parameters. This processing is as already described as the processing of the shadow calculation means 7. As a result, a predetermined brightness value Kn is defined in each part of the wrinkled surface S. Subsequently, in step S47, the image data used as the texture is input using the image data input means 3. Then, in step S48, the texture coordinate values (u,
Using v) as a clue, texture mapping is performed in consideration of brightness. This processing is as already described as the processing of the texture mapping means 8. That is,
UV obtained from the texture coordinate value (u, v) as a clue
The pixel value Gn of a specific pixel on the image plane is blended with the luminance value Kn obtained by the luminance calculation, and the pixel having the blended pixel value is defined on the wrinkled surface S, and this is defined on the XY plane. Two-dimensional image data is obtained by projecting. Finally, in step S49, the printing plate / printing process is executed based on the two-dimensional image data output from the texture mapping means 8.

<Application to Endless Design> In printing for building materials such as wallpaper and floor materials, it is common to use endless design. For example, in the example shown in FIG. 12, unit regions W hatched in the drawing are arranged in 4 rows and 4 columns to define a region having a 16 times larger area. In this case, the patterns in the unit area W are spatially repeatedly arranged, but the right side and the left side of the unit area W are continuous as a pattern, and the upper side and the lower side are continuous as a pattern. If a pattern is used, even if such a repetitive arrangement is performed, the entire pattern does not feel uncomfortable. In addition, when designing a design, it is efficient to design only the design corresponding to the unit area W.

To apply the present invention to a printed matter using such an endless pattern, first, image data of the endless pattern is prepared. That is, image data is prepared so that pixels having a specific positional relationship on the contour have substantially the same pixel value so that continuous tones can be obtained even when a plurality of identical patterns are arranged adjacent to each other. In the case of the present invention, it is not enough to use only the image data of such an endless pattern, and it is necessary to use an endless wrinkled surface. That is, the image data of the endless pattern is taken in on the UV image plane shown in FIG. 2, and X shown in FIG.
A polygonal array is defined on the Y reference plane, and each vertex of this polygon is randomly displaced to generate a wrinkled surface S as shown in FIG.
When forming the, it is necessary to consider so that the wrinkled surface S becomes an endless wrinkled surface. Here, the endless wrinkled surface should be referred to as “wrinkled surface such that the contour portion becomes a continuous surface when a large number of wrinkled surfaces are arranged adjacent to each other”.
Since the pattern finally obtained by the present invention is the one in which the design is deformed based on this wrinkled surface and the shadow information is added, by using the endless design and the endless wrinkled surface, , It will be possible to obtain a pattern with continuous tone as a whole.

In order to generate such an endless wrinkled surface, when the vertices on the reference plane are randomly moved, the vertices on the contour which have a specific positional relationship are almost the same mode ( The movement may be performed in the same movement direction and the same movement amount). For example, when a large number of equilateral triangles as shown in FIG. 13 are defined on the reference plane, the vertices a1, a2, a3, and a4 at the four corners are moved in the same manner, and the vertices b along the upper side are moved.
1 to h1 are moved in the same manner as the vertices b2 to h2 along the lower side, and the vertices i1 to i1 along the left side are moved.
With respect to o1, it is possible to generate an endless wrinkled surface by moving in the same manner as the vertices i2 to o2 along the right side.

As shown in FIG. 14, when an endless pattern in which a continuous pattern is formed by spatially repeatedly arranging the unit regions W by shifting by half pitch and shifting them by half pitch. The endless wrinkled surface is obtained so that a continuous surface can be obtained when they are arranged adjacent to each other. That is, as shown in FIG. 15, vertices a1, a2, a3, a4 at the four corners and apex a5 at the center of the upper side.
And the apex a6 in the center of the lower side are all moved in the same manner, and the vertices b1 to d1 in the left half of the upper side are moved in the same manner as the vertices b2 to d2 in the right half of the lower side. The vertices f1 to h1 on the right half are moved in the same manner as the vertices f2 to h2 on the left half of the lower side, and the vertices i1 to o1 along the left side are
By moving in the same manner as the vertices i2 to o2 along the right side, it is possible to generate an endless wrinkled surface with a half pitch shift.

In performing shadow calculation using such an endless wrinkled surface, a parallel light source parallel to the reference plane is used as a light source so that the same brightness value can be obtained at the corresponding boundary portion. Care should be taken to use a projection plane parallel to the plane.

[0068]

As described above, according to the present invention, it is possible to relatively easily generate a pattern in which pseudo wrinkles are expressed by using a computer.

[Brief description of drawings]

FIG. 1 is a flowchart showing a procedure of a first exemplary embodiment of the present invention.

FIG. 2 is a diagram showing image data prepared on a UV image plane in step S11 of the flowchart of FIG.

3 is a diagram showing a state in which a large number of equilateral triangles are defined on an XY reference plane in step S12 of the flowchart of FIG.

FIG. 4 is a diagram showing a wrinkled surface S formed in step S13 of the flowchart of FIG.

5 is a diagram showing projection points QQn obtained on the projection plane by the projection processing in step S15 of the flowchart of FIG.

FIG. 6 is a flowchart showing a procedure of the second exemplary embodiment of the present invention.

7 is a diagram showing a reference polygon Tr defined on the UV image plane in step S23 of the flowchart of FIG. 6;

8 is a diagram showing a pixel associating process on the wrinkled surface in step S25 of the flowchart of FIG.

FIG. 9 is a flowchart showing the procedure of the third embodiment of the present invention.

FIG. 10 is a block diagram showing a basic configuration of a pattern generation device according to the present invention.

11 is a flowchart showing a specific pattern generation procedure using the apparatus shown in FIG.

FIG. 12 is a diagram showing a state in which endless patterns in a unit area W are spatially repeatedly arranged to form a pattern.

13 is a diagram showing a method for generating an endless wrinkled surface for applying the present invention to the pattern shown in FIG.

FIG. 14 is a diagram showing a state in which the endless patterns in the unit area W are spatially repeatedly arranged while being shifted by a half pitch and a pattern is formed.

FIG. 15 is a diagram showing a method for producing an endless wrinkled surface for applying the present invention to the pattern shown in FIG. 14;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Parameter input means 2 ... Random number generation means 3 ... Image data input means 4 ... Polygon definition means 5 ... Texture coordinate allocation means 6 ... Vertex displacement means 7 ... Shade calculation means 8 ... Texture mapping means 9 ... Printing plate means 10 ... Printing means An ... Polygon apex Gn ... Pixel value Kn ... Luminance value L ... Light source Pn ... Pixel Qn ... Arbitrary point on wrinkled surface QQn ... Projection point Rn ... Reference point S ... Wrinkled surface Td Deformation triangle Tr ... Reference triangle U, V ... Coordinate axes of two-dimensional coordinate system in which image plane is defined W ... Unit area X, Y ... Coordinate axes of two-dimensional coordinate system in which reference plane is defined X, Y, Z ... Existence Coordinate axes of the three-dimensional coordinate system in which the wrinkle surface is defined

(72) Inventor Yasuhiro Hayashi 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo Within Dai Nippon Printing Co., Ltd. (72) 1-1-1 Ichigaya-Kagacho, Shinjuku-ku, Tokyo Dai Nippon Printing Co., Ltd. (72) Inventor Yu Okamoto 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo Dai Nippon Printing Co., Ltd. (72) Inventor Yoshio Sukegawa 311 Takemasawa, Miyoshi-cho, Iruma-gun Saitama Dainippon Total Process Building Materials

Claims (9)

[Claims] 1. A method of generating a pattern in which pseudo wrinkles are expressed, and a step of preparing image data expressing a pattern by arranging pixels each having a unique pixel value on an image plane. , A step of defining a number of polygons arranged side by side on a predetermined reference plane so as not to create a gap, and moving each vertex of the polygon on the reference plane randomly in a three-dimensional space Randomly deform, forming a wrinkled surface as a set of the inner surface of each polygon after deformation, and assuming a light source at a predetermined position in three-dimensional space, at each position of the wrinkled surface, The step of defining a brightness value according to the shadow generated based on the light source, and by projecting the wrinkled surface on a predetermined projection surface, according to the corresponding portion on each wrinkled surface at each position on this projection surface. Defined brightness value and before The step of associating each pixel on the image plane with a luminance value by associating the pixel on the image plane with each position on the projection plane, and the pixel value of the pixel on the image plane. , A pattern that expresses pseudo wrinkles, characterized by having a step of correcting based on the brightness values respectively associated with each other, and a step of generating a pattern from a set of pixels having the corrected pixel value. How to generate. 2. A method of generating a pattern in which pseudo wrinkles are expressed, and a step of preparing image data expressing a pattern by arranging pixels each having a unique pixel value on an image plane. , A step of defining a number of polygons on a predetermined reference plane side by side so that no gaps are formed, and associating the image plane with the reference plane, and referring to each vertex of the polygon on the reference plane. Defining a point on the image plane, defining a reference polygon having this reference point as a vertex, and moving each vertex of the polygon on the reference plane randomly in a three-dimensional space Randomly deforming the polygon, forming a wrinkled surface as a set of the inclusion surface of each polygon after the deformation, the deformed polygon forming the wrinkled surface and the reference polygon on the image plane. Correspond to this correspondence Then, the step of associating pixels on the image plane with each position on the wrinkled surface, and by projecting the wrinkled surface onto a predetermined projection surface, the image at each position on this projection surface, respectively. A method of generating a pseudo-wrinkle-expressing pattern, comprising: associating pixels on a plane with each other; and generating a pattern by a set of pixels associated with each other on the projection surface. 3. The method according to claim 2, wherein a light source is assumed at a predetermined position in a three-dimensional space, and at each position of the wrinkled surface, a brightness value is defined according to the shadow generated based on the light source. A step of associating a luminance value corresponding to each position on each pixel on the image plane with each other, and a step of correcting the pixel value of the pixel on the image plane based on the associated luminance value, Is added, and the pattern is generated by the set of pixels having the corrected pixel value. 4. The method according to any one of claims 1 to 3, wherein an equilateral triangle having a dimension D on one side is used as a polygon defined on a reference plane, and the amount of movement is changed when randomly moving the vertices. A method for generating a pattern in which pseudo wrinkles are expressed, wherein the maximum value is set to D / 2. 5. The method according to any one of claims 1 to 4, wherein a specific position is provided on a contour so that continuous tone can be obtained as a whole even when a plurality of identical patterns are prepared and arranged adjacent to each other. When preparing image data such that the related pixels have substantially the same pixel value, and randomly moving the vertices on the reference plane, regarding the vertices on the contour that have the specific positional relationship, A method of generating a pseudo wrinkle-expressing pattern, characterized in that the patterns generated based on the pattern are moved spatially and repeatedly in substantially the same manner. 6. A device for generating a pattern that artificially expresses wrinkles, comprising: parameter input means for inputting a predetermined parameter; random number generation means for generating a random number; and image data showing a predetermined texture image. Image data input means for inputting on a predetermined image plane, polygon defining means for defining a number of polygons arranged side by side on a predetermined reference plane so as not to create a gap based on the parameters, and the image plane Texture coordinate assigning means for associating with the reference plane, defining reference points corresponding to respective vertices of polygons on the reference plane on the texture image, and defining reference polygons having the reference points as vertices; , By randomly moving each vertex of the polygon on the reference plane in a three-dimensional space based on the parameter, thereby deforming each polygon at random, Assuming a light source at a predetermined position in a three-dimensional space and a vertex displacement means that forms a wrinkled surface as a set of each polygonal inclusion surface after deformation, and based on the light source at each position of the wrinkled surface. The shadow calculation means for calculating the brightness according to the generated shadow, the deformed polygon forming the wrinkled surface and the reference polygon on the texture image are associated with each other, and based on this correspondence, on the wrinkled surface A texture mapping unit that maps the texture image in consideration of the brightness at each position and outputs the two-dimensional image data by projecting the mapped texture image on a predetermined projection surface. A device that creates patterns that artificially represent wrinkles. 7. A printed matter having a pattern produced by the method according to claim 1. 8. A printed matter on which a pattern based on a predetermined picture is printed, wherein a large number of polygons arranged so as not to create a gap on a printing surface are defined, and each polygon has a random luminance value. A pattern that expresses a wrinkle in a pseudo manner, characterized in that a part of the pattern corresponding to the position of this polygon is expressed in a manner corresponding to each luminance value in each polygon. Printed matter having. 9. A printed matter on which a pattern based on a predetermined pattern is printed, wherein a large number of polygons arranged so as not to create a gap on a printing surface are defined, and each polygon is formed with this polygon. A printed matter having a pattern in which pseudo wrinkles are expressed, characterized in that a part of the pattern corresponding to the position of the polygon is expressed in a unique modification.