Method for creating modeling data, modeling data generation device, and modeling system

Abstract

To properly mold a molded product having various textures.SOLUTION: Disclosed is a preparation method of molding data for preparing molding data showing a molded product 50 and includes: a shape determination step of determining a shape of the molded product 50; a shade data acquisition step of acquiring shade data showing a shade formed on a surface of the molded product 50 corresponding to a shape of the molded product 50; and a surface color decision step of determining a color for coloration of each position of the surface of the molded product 50 based on the shade data.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for creating modeling data, a modeling data generation device, and a modeling system.

Background Art

[0002] Conventionally, a modeling device (3D printer) that creates a modeled object using an inkjet head has been known (see, for example, Patent Document 1). In such a modeling device, for example, a modeled object is modeled by the layer stacking method by stacking a plurality of layers of ink formed by an inkjet head.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When modeling a modeled object with a modeling device, usually, modeling is performed using a modeling material prepared in advance according to the configuration of the modeling device. For example, when performing modeling using an inkjet head, ink for the inkjet head is used as the modeling material. And in this case, it is considered that the texture of the modeled object will be the texture determined according to the modeling material. On the other hand, in recent years, due to the expansion of the uses of modeling devices, etc., it may be desired to create modeled objects with higher design quality. Also, in this case, for example, it may be desired to perform modeling with a more diverse range of textures. Therefore, an object of the present invention is to provide a method for creating modeling data, a modeling data generation device, and a modeling system that can solve the above problems.

Means for Solving the Problems

[0005] The inventor of the present application has conducted intensive research on a three-dimensional object to be formed by a forming apparatus and a method for forming objects with various textures. By conducting various experiments and the like on the perceptual system by which humans perceive texture, it has been found that even when the physical characteristics corresponding to the texture are not changed, by changing the way of coloring the surface of the object, the observer can be made to perceive the desired texture. More specifically, when observing an object, usually, due to the ambient light, a shadow is formed on the surface of the object according to its shape and the like. Also, in this case, it can be considered that the way the shadow is formed reflects physical characteristics such as the scattering phenomenon occurring near the surface of the object and the state of light transport. On the other hand, the inventor of the present application has considered changing the texture perceived by the observer in an illusory manner by performing coloring on the surface of the object according to the shadow formed on the surface of the object so that the observer visually recognizes that a shadow is formed in a state different from the original shadow.

[0006] Further, the inventor of the present application has found the features necessary to obtain such an effect through further intensive research and has reached the present invention. In order to solve the above problems, the present invention is a method for creating modeling data that is data indicating an object to be modeled by a modeling apparatus, the method including a shape determination step of determining the shape of the object, a shadow data acquisition step of acquiring shadow data that is data indicating a shadow formed on the surface of the object according to the shape of the object, and a surface color determination step of determining a color for coloring each position on the surface of the object based on the shadow data.

[0007] When configured in this way, by determining the color for coloring each position on the surface of the object based on the shadow data, the state of the object can be visually recognized by the observer as if a shadow is formed in a state different from the original shadow, for example. Also, thereby, for example, the texture perceived by the observer can be changed. Therefore, if configured in this way, for example, an object expressing various textures can be appropriately formed. Also, thereby, for example, forming with a desired texture or forming a highly designed object can be more appropriately performed.

[0008] In this configuration, the color used for coloring each position on the surface of the shaped object may be, for example, only one color. In this case, regarding the determination of the color for coloring each position on the surface of the shaped object, it can be considered, for example, to determine the color density, etc. Regarding the determination of the color density, it can be considered, for example, to determine the gradation of the color at each position, etc. Also, regarding the determination of the color density, it can also be considered, for example, to determine the brightness of the color, etc. For each position on the surface of the shaped object, color coloring (for example, full-color coloring) may be performed. In this case, the determination of the color for coloring each position on the surface of the shaped object may be, for example, to determine the color density for each of a plurality of colors that are the basic colors of the color expression.

[0009] In this configuration, in the shadow data acquisition stage, as shadow data, for example, a shadow image that is an image showing the shadow generated on the surface of the shaped object is acquired. In the surface color determination stage, for example, an inverted image that is an image obtained by performing gradation inversion on the shadow image may be generated. In this case, for example, based on the inverted image, the color for coloring each position on the surface of the shaped object is determined. With this configuration, for example, the impression received by the observer due to the shadow generated on the shaped object can be appropriately changed. Also, thereby, for example, the texture perceived by the observer for the shaped object can be appropriately changed. Also, in this case, in the surface color determination stage, for example, based on the inverted image, the color for coloring each position on the surface of the shaped object is determined so that the influence of the shadow generated on the surface of the shaped object according to the shape of the shaped object is reduced and perceived by the observer. With this configuration, for example, the texture perceived by the observer for the shaped object can be appropriately changed. Also, for the shadow image, for example, it is also conceivable to perform processing other than gradation inversion. In this case, for example, in addition to gradation inversion, it is conceivable to further perform processing such as limiting the number of gradations and gamma correction processing. With this configuration, for example, the influence of the shadow can be varied in various ways.

[0010] Also, the texture perceived by an observer due to the influence of the shadow generated on the surface of the modeled object by the light irradiated onto the modeled object is defined as the perceived texture, and when the perceived texture perceived in the modeled object with the color of each position on the surface being made uniform is defined as the uniform color texture, in the surface color determination stage, for example, the color to be applied to each position on the surface of the modeled object is determined so that a perceived texture different from the uniform color texture is perceived by the observer. With such a configuration, for example, the texture perceived by the observer for the modeled object can be appropriately changed. Also, as the perceived texture, for example, a texture related to translucency (translucent feeling) can be considered. In this case, in the surface color determination stage, for example, the color to be applied to each position on the surface of the modeled object is determined so that at least a part of the translucency in the modeled object is perceived to be higher due to the perceived texture being different from the uniform color texture. With such a configuration, for example, a high translucency can be appropriately expressed as the texture of the modeled object.

[0011] Also, in the shape determination stage, for example, the shape of the modeled object is determined based on the shape data which is the data indicating the shape of the modeled object. And in the surface color determination stage, for example, a texture to be attached to the surface of the three-dimensional shape indicated by the shape data is generated. In this case, as this texture, for example, it is conceivable to generate a texture indicating the color to be applied to each position on the surface of the modeled object. With such a configuration, for example, the color to be applied to each position on the surface of the modeled object can be appropriately specified. Also, in this case, the method for creating the modeling data further includes, for example, a modeling data generation stage for generating the modeling data based on the shape data and the texture. With such a configuration, for example, the modeling data can be appropriately created.

[0012] Also, in the modeling data generation stage, for example, modeling data indicating a modeled object having a configuration including a region for changing the texture of the modeled object may be generated. Further, as such modeling data, for example, it is conceivable to generate modeling data indicating a modeled object including a scattering region containing a scatterer that is an inclusion having the property of scattering light. In this case, the scattering region is, for example, a region that includes a scatterer and varies the amount of scatterers included per unit volume depending on the position. With such a configuration, for example, the actual texture of the modeled object can also be varied in various ways. Also, in this case, by combining determining the color for coloring each position on the surface of the modeled object based on the shadow data and varying the actual texture of the modeled object by the scattering region, the texture perceived by the observer for the modeled object can be varied in a more diverse manner. Also, in this case, it is conceivable to determine the manner of forming the scattering region based on the shadow data. More specifically, in this case, in the modeling data generation stage, for example, by determining the amount of scatterers included per unit volume at each position in the scattering region based on the shadow data, modeling data indicating a modeled object including the scattering region is generated. With such a configuration, for example, the impression received by the observer due to the shadow generated on the modeled object can be changed more appropriately.

[0013] Also, in the shadow data acquisition stage, for example, shadow data is acquired by computer simulation using the AO method (Ambient Occlusion method). With this configuration, for example, shadow data can be easily and appropriately acquired. In the shadow data acquisition stage, shadow data may be acquired by computer simulation using a method other than the AO method. Also, instead of computer simulation, for example, shadow data may be acquired by actually performing measurement. In this case, in the shadow data acquisition stage, for example, a three-dimensional object having the same shape as the shape determined in the shape determination stage is created, and shadow data is acquired based on the shadow generated on the surface of the three-dimensional object by irradiating the three-dimensional object with light. With this configuration, for example, shadow data can be appropriately acquired with high accuracy. In this case, for the three-dimensional object to be measured, for example, it is conceivable to perform shaping using a shaping device. Also, for this three-dimensional object, it may be created by a method other than shaping by a shaping device. Also, as the shaping data, for example, it is also conceivable to create data indicating an existing three-dimensional object that has existed since before the start of creating the shaping data. And in such a case, for example, it is also conceivable to acquire shadow data using the existing three-dimensional object. More specifically, in this case, in the shadow data acquisition stage, for example, shadow data is acquired based on the shadow generated on the surface of the existing three-dimensional object. Even in the case configured in this way, for example, shadow data can be appropriately acquired with high accuracy.

[0014] Also, as a configuration of the present invention, it is also conceivable to use a shaping data generation device, a shaping system, etc. having the same features as described above. Also in these cases, for example, the same effects as described above can be obtained.

Advantages of the Invention

[0015] According to the present invention, for example, a shaped object expressing various textures can be appropriately shaped.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

MODE FOR CARRYING OUT THE INVENTION

[0017] Hereinafter, embodiments according to the present invention will be described with reference to the drawings. Fig. 1 shows an example of a modeling system 10 according to an embodiment of the present invention. Fig. 1(a) shows an example of a configuration of the modeling system 10. In this example, the modeling system 10 is a modeling system that models a three-dimensional object, and includes a modeling apparatus 12 and a control PC 14. Regarding the object to be modeled in the modeling system 10, for example, it can be considered as a three-dimensional three-dimensional structure or the like.

[0018] The shaping device 12 is a device that executes the shaping of a shaped object, and shapes the shaped object according to the control of the control PC 14. Also, in this example, the shaping device 12 is a full-color shaping device capable of shaping a shaped object colored in full color, receives shaping data, which is data indicating the shaped object to be shaped, from the control PC 14, and shapes the shaped object based on the shaping data. The control PC 14 is a computer (host PC) that controls the operation of the shaping device 12, and controls the shaping operation by the shaping device 12 by supplying the shaping data to the shaping device 12. Also, in this example, the control PC 14 is an example of a shaping data generation device, generates shaping data indicating a shaped object with at least a part of the surface where color can be visually recognized from the outside colored, and supplies it to the shaping device 12. The operation of generating the shaping data in the control PC 14 will be described in more detail later.

[0019] Note that, in this example, the shaping system 10 is composed of the shaping device 12 and the control PC 14, which are a plurality of devices. In a modified example of the shaping system 10, the shaping system 10 may be composed of a single device. In this case, for example, it is conceivable to configure the shaping system 10 with a single shaping device 12 including the functions of the control PC 14. Also, the shaping system 10 may further include a device other than the shaping device 12 and the control PC 14.

[0020] Next, the configuration of the shaping device 12 will be described. FIG. 1(b) shows an example of the configuration of the main part of the shaping device 12. In this example, the shaping device 12 is a 3D printer that shapes a shaped object 50 by a layer stacking method, and includes a head unit 102, a shaping table 104, a scanning drive unit 106, and a control unit 110. In this case, for the layer stacking method, for example, it can be considered as a method of shaping the shaped object 50 by stacking layers formed of a shaping material. Also, except for the points described below, the shaping device 12 may have the same or similar configuration as a known shaping device. More specifically, except for the points described below, the shaping device 12 may have the same or similar features as a known shaping device that performs shaping by discharging droplets that become the material of the shaped object 50 using an inkjet head. Also, in addition to the illustrated configuration, the shaping device 12 may further include various configurations necessary for shaping the shaped object 50, for example.

[0021] The head unit 102 is configured to discharge the material of the shaped object 50. In this example, ink is used as the material of the shaped object 50. The ink can be considered as, for example, a functional liquid or the like. Also, the ink can be considered as, for example, a liquid discharged from an inkjet head. Also, in this example, the head unit 102 discharges ink that cures according to predetermined conditions from a plurality of inkjet heads as the material of the shaped object 50. Then, by curing the ink after landing, each layer constituting the shaped object 50 is stacked to form the shaped object by the layer stacking method. Also, in this example, as such ink, an ultraviolet curable ink (UV ink) that cures from a liquid state by irradiation with ultraviolet rays is used. Also, in addition to the material of the shaped object 50, the head unit 102 further discharges the material of the support layer 52. Thereby, the head unit 102 forms the support layer 52 around the shaped object 50 or the like as necessary. The support layer 52 can be considered as, for example, a laminated structure that supports at least a part of the shaped object 50 during shaping. The support layer 52 is formed as necessary during the shaping of the shaped object 50 and removed after the completion of the shaping.

[0022] The shaping table 104 is a pedestal member that supports the object 50 being shaped, is disposed at a position facing the inkjet head in the head unit 102, and places the object 50 and the support layer 52 being shaped on the upper surface. Also, in this example, the shaping table 104 has a configuration that can move in the stacking direction (Z direction in the figure), and is driven by the scanning drive unit 106 to move in the stacking direction in accordance with the progress of the shaping of the object 50. In this case, for the stacking direction, for example, it can be considered as the direction in which the shaping material is stacked in the layer-by-layer shaping method or the like. Also, in this example, the stacking direction is a direction orthogonal to the main scanning direction (Y direction in the figure) and the sub-scanning direction (X direction in the figure) preset in the shaping apparatus 12.

[0023] The scanning drive unit 106 is a drive unit that causes the head unit 102 to perform a scanning operation that relatively moves with respect to the object 50 being formed. In this example, regarding the relative movement with respect to the object 50 being formed, for example, it can be considered as moving relatively with respect to the building platform 104. Also, regarding causing the head unit 102 to perform a scanning operation, for example, it can be considered as causing the inkjet head included in the head unit 102 to perform a scanning operation. In this example, the scanning drive unit 106 causes the head unit 102 to perform a main scanning operation (Y scanning), a sub-scanning operation (X scanning), and a lamination direction scanning operation (Z scanning) as the scanning operations. In this case, regarding the main scanning operation, for example, it can be considered as an operation of discharging ink while relatively moving in the main scanning direction with respect to the object 50 being formed. Regarding the sub-scanning operation, for example, it can be considered as an operation of relatively moving with respect to the object 50 being formed in the sub-scanning direction orthogonal to the main scanning direction. Also, regarding the sub-scanning operation, for example, it can also be considered as an operation of relatively moving with respect to the building platform 104 in the sub-scanning direction by a preset feed amount. In this example, the scanning drive unit 106 causes the head unit 102 to form an ink layer by performing the main scanning operation and the sub-scanning operation on the head unit 102. Also, regarding the lamination direction scanning operation, for example, it can be considered as an operation of relatively moving in the lamination direction with respect to the object 50 being formed. The scanning drive unit 106 adjusts the relative position of the inkjet head with respect to the object 50 being formed in the lamination direction by causing the head unit 102 to perform the lamination direction scanning operation in accordance with the progress of the forming operation.

[0024] The control unit 110 is configured to include, for example, the CPU of the modeling device 12, and controls the operation of forming the modeled object 50 by controlling each part of the modeling device 12. Also, in this example, the control unit 110 generates slice data, which is data indicating the cross section of the modeled object 50 to be modeled, based on the modeling data received from the control PC 14. Then, in the operation of forming each ink layer that constitutes the modeled object 50, by controlling the operation of each inkjet head in the head unit 102 based on the slice data, the ink used for forming the modeled object is ejected from each inkjet head. According to this example, for example, the formation of the modeled object 50 can be appropriately executed.

[0025] Subsequently, the configuration of the head unit 102 in the modeling device 12 will be described in more detail. FIG. 1(c) shows an example of the configuration of the head unit 102. In this example, the head unit 102 includes a plurality of inkjet heads 202, a plurality of ultraviolet light sources 204, and a flattening roller 206. Also, as the plurality of inkjet heads 202, as shown by distinguishing them with letters s to t in the figure, there are an inkjet head 202s, an inkjet head 202w, an inkjet head 202y, an inkjet head 202m, an inkjet head 202c, an inkjet head 202k, and an inkjet head 202t. These plurality of inkjet heads 202 are arranged side by side in the main scanning direction with their positions in the sub-scanning direction aligned. Also, each inkjet head 202 has a nozzle row in which a plurality of nozzles are arranged in a predetermined nozzle row direction on the surface facing the modeling table 104. In this example, the nozzle row direction is a direction parallel to the sub-scanning direction.

[0026] Among these inkjet heads 202, the inkjet head 202s is an inkjet head that discharges the material of the support layer 52. As the material of the support layer 52, for example, a known material for the support layer can be preferably used. The inkjet head 202w is an inkjet head that discharges white (W color) ink. In this example, the white ink is an example of a light-reflective ink, and is used, for example, when forming a region (light-reflective region) having the property of reflecting light in the shaped object 50. This light-reflective region reflects light incident from the outside of the shaped object 50 when performing color coloring on the surface of the shaped object 50 in full-color expression or the like. Regarding full-color expression, for example, it can be considered as a color expression performed by a possible combination of the subtractive color mixing method using process color inks.

[0027] The inkjet heads 202y, 202m, 202c, and 202k (hereinafter referred to as inkjet heads 202y to k) are inkjet heads for coloring used when forming the colored shaped object 50. More specifically, the inkjet head 202y discharges yellow (Y color) ink. The inkjet head 202m discharges magenta (M color) ink. The inkjet head 202c discharges cyan (C color) ink. The inkjet head 202k discharges black (K color) ink. Also, in this example, each color of YMCK is an example of a process color. The inkjet head 202t is an inkjet head that discharges clear ink. Regarding the clear ink, for example, it can be considered as an ink that is colorless and transparent (T) to visible light. Also, regarding the clear ink, for example, it can be considered as an ink in which a coloring material is not intentionally added.

[0028] The plurality of ultraviolet light sources 204 are light sources (UV light sources) for curing the ink and generate ultraviolet rays for curing the ultraviolet-curable ink. In this example, each of the plurality of ultraviolet light sources 204 is disposed at one end side and the other end side in the main scanning direction in the head portion 102 so as to sandwich the arrangement of the inkjet heads 202 therebetween. As the ultraviolet light source 204, for example, a UVLED (ultraviolet LED) or the like can be preferably used. Also, as the ultraviolet light source 204, it is also conceivable to use a metal halide lamp, a mercury lamp, or the like. The flattening roller 206 is a flattening means for flattening the ink layer formed during the shaping of the shaped object 50. The flattening roller 206 flattens the ink layer, for example, by contacting the surface of the ink layer during the main scanning operation and removing a part of the uncured ink. By using the head portion 102 configured as described above, for example, the ink layer constituting the shaped object 50 can be appropriately formed. Also, by forming a plurality of ink layers stacked on each other, for example, the shaped object 50 can be appropriately shaped.

[0029] Note that the specific configuration of the head portion 102 is not limited to the configuration described above and can be variously modified. For example, the head portion 102 may further have an inkjet head for a color other than the above as an inkjet head for coloring. Also, the arrangement of the plurality of inkjet heads in the head portion 102 can be variously modified. For example, for some of the inkjet heads, the position in the sub-scanning direction may be shifted from that of the other inkjet heads.

[0030] Next, the configuration of the modeled object 50 modeled by the modeling apparatus 12 in this example will be described in more detail. FIG. 2 is a diagram for explaining the configuration of the modeled object 50 modeled by the modeling apparatus 12. FIG. 2(a) is a diagram showing an example of the configuration of the modeled object 50, and shows an example of the configuration of the X-Y cross section, which is a cross section of the modeled object 50 perpendicular to the stacking direction (Z direction). In this case, the configurations of the Y-Z cross section and the X-Z cross section of the modeled object 50 perpendicular to the X direction and the Y direction are also the same. Also, in FIG. 2, for the sake of illustration, an example of the configuration of the modeled object 50 having a simple shape is shown. During actual modeling, the modeling apparatus 12 can also model a modeled object 50 having a more complex shape. More specifically, in the modeling apparatus 12, for example, it is conceivable to model a modeled object 50 showing natural objects such as humans and animals.

[0031] In this example, the modeling apparatus 12 uses an inkjet head 202y~k (see FIG. 1) or the like to model a modeled object 50 with a colored surface. Regarding the coloring of the surface of the modeled object 50, for example, it can be considered that at least a part of the region where the color can be visually recognized from the outside in the modeled object 50 is colored. Also, in this case, the modeling apparatus 12 models a modeled object 50 having a light reflection region 152 and a coloring region 154, as shown in the figure, for example. In this case, the control PC 14 (see FIG. 1) generates modeling data indicating the modeled object 50 having these regions and supplies it to the modeling apparatus 12, causing the modeling apparatus 12 to model the modeled object 50. Also, the modeling apparatus 12 forms a support layer 52 (see FIG. 1) around the modeled object 50 or the like as necessary.

[0032] The light reflection region 152 is a light - reflective region for reflecting light incident from the outside of the shaped object 50 through the colored region 154. In this example, the shaping device 12 forms the light reflection region 152 inside the shaped object 50 using white ink ejected from an inkjet head 202w (see FIG. 1). Also, in this example, the shaping device 12 forms a light reflection region 152 that also serves as an internal region. In this case, the internal region can be considered, for example, as a region constituting the inside of the shaped object 50. In a modification of the configuration of the shaped object 50, the internal region may be formed as a region separate from the light reflection region 152. In this case, the shaping device 12 forms the internal region using, for example, any ink other than the material of the support layer 52. Also, a light reflection region 152 is formed around the internal region.

[0033] The colored region 154 is a region colored by colored ink ejected from inkjet heads 202y - k. In this example, the shaping device 12 forms the colored region 154 around (outside) the light reflection region 152 using colored ink ejected from inkjet heads 202y - k and clear ink ejected from an inkjet head 202t (see FIG. 1). Also, in this case, in the shaping device 12, various colors are expressed, for example, by adjusting the ejection amount of the colored ink of each color to each position. With such a configuration, for example, color coloring (e.g., full - color coloring) with various colors can be performed for each position on the surface of the shaped object 50. Also, in this case, by varying the color to be colored depending on the position, various patterns, characters, etc. can be drawn on the surface of the shaped object 50. Also, in this example, clear ink is used to compensate for the change in the amount of colored ink caused by the difference in color. With such a configuration, for example, each position of the colored region 154 can be appropriately colored with a desired color.

[0034] Depending on the use of the shaped object 50 and the like, it may also be considered to use only one color for the color to be applied to each position on the surface of the shaped object 50. In this case, for example, it is conceivable to form the colored region 154 using an ink for single-color application (for example, an ink of K color) and a clear ink. Further, for example, it is conceivable to vary the color density of the color applied with the ink for single-color application depending on the position in the colored region 154. In this case, for example, the color density can be changed by changing the amount of the coloring ink discharged per unit volume. Also, for the clear ink, for example, it can be considered to be used to compensate for the change in the amount of the coloring ink that causes a difference in color density.

[0035] In a modified example of the configuration of the shaped object 50, for example, as shown in FIG. 2(b), another region may be further formed between the light reflection region 152 and the colored region 154. FIG. 2(b) is a diagram showing a modified example of the configuration of the shaped object 50. In this modified example, the shaped object 50 includes a light reflection region 152, a scattering region 156, and a colored region 154. In this case, the light reflection region 152 and the colored region 154 are, for example, the same or similar regions as the light reflection region 152 and the colored region 154 in FIG. 2(a). Also, the scattering region 156 is formed between the light reflection region 152 and the colored region 154. In this case, the control PC 14 generates shaping data indicating the shaped object 50 including these regions and supplies it to the shaping device 12, causing the shaping device 12 to shape the shaped object 50.

[0036] Also, in this modified example, the scattering region 156 is a region formed using white ink and clear ink. In this case, for the coloring material (e.g., pigment, etc.) contained in the white ink, it can be considered, for example, as an example of a scatterer that is an inclusion having the property of scattering light. Also, for the scattering region 156, it can be considered, for example, as a region having the property of scattering light by containing scatterers at a ratio determined according to the usage ratio of the clear ink and the white ink. When configured in this way, by forming the scattering region 156 inside the coloring region 154, for example, the actual texture of the shaped object 50 can be varied in various ways. Also, thereby, for example, compared with the case where the scattering region 156 is not formed, the texture of the shaped object 50 perceived by an observer with respect to the shaped object 50 can be varied more diversely. Therefore, the scattering region 156 can also be considered, for example, as a region for varying the texture of the apparent shaped object 50 more diversely. In a further modified example of the configuration of the shaped object 50, it is also conceivable to omit the light reflection region 152, etc. In this case, the scattering region 156 can be considered as a region also serving as the light reflection region 152. Also, in this case, the shaped object 50 includes, for example, an internal region, the scattering region 156, and the coloring region 154. The modified example using the scattering region 156 will be described in more detail later.

[0037] Subsequently, the characteristics of the shaped object 50 formed based on the shaping data in the shaping apparatus 12 of this example and the operation of generating the shaping data in the control PC 14 will be described in more detail. As described above, in the shaping apparatus 12 of this example, ink ejected from an inkjet head is used as the material of the shaped object 50. And in this case, it can be considered that the texture of the shaped object 50 to be shaped becomes a texture reflecting the characteristics of the ink. However, depending on the use of the shaped object 50, etc., there may be cases where it is desired to express more diverse textures in the shaped object 50.

[0038] In this regard, the inventor of the present application has found that, even when the physical properties corresponding to the texture are not changed, by changing the way of coloring the surface of the shaped object, it is possible to make an observer perceive a desired texture by conducting various experiments and the like regarding the human perception system for perceiving texture. More specifically, for example, when observing a three-dimensional object such as the shaped object 50 shaped by the shaping device 12, due to the ambient light, shadows will be generated on the surface of the object according to its shape and the like. Also, in this case, it can be considered that the way the shadow is formed reflects physical properties such as the scattering phenomenon and the state of light transport occurring near the surface of the object. Therefore, for example, if the appearance of the shadow changes, it is conceivable that the texture perceived by the observer also changes. Thus, the inventor of the present application considered making the observer visually recognize that a shadow is occurring in a state different from the original shadow by performing coloring on the surface of the shaped object 50 according to the shadow actually occurring on the surface of the shaped object, and changing, so to speak, in an illusory way, the texture perceived by the observer. In this case, the coloring according to the shadow occurring on the surface of the shaped object 50 can be considered, for example, as coloring that changes the appearance of the actually occurring shadow. Also, the inventor of the present application considered using a method (texture control method) of using a texture indicating the color to be colored on the surface of the shaped object 50 as a method of changing the apparent texture in this way. Such a method can also be considered, for example, as a method of pseudo-reproducing a desired texture using a texture for texture adjustment and the like.

[0039] Also, in this case, for example, it is conceivable to generate shaping data by the operation shown in FIG. 3. FIG. 3 is a diagram for explaining the operation of generating shaping data in the control PC 14. FIG. 3(a) is a flowchart showing an example of the operation of generating shaping data. As described above, in this example, the control PC 14 generates shaping data indicating a shaped object with at least a part of the surface where color can be visually recognized from the outside colored, and supplies it to the shaping device 12. Also, in this case, a texture for texture adjustment is used to change the apparent texture of the shaped object 50.

[0040] More specifically, in this case, the control PC 14 acquires 3D model data by receiving, from the outside, data created in advance by, for example, a user or the like (S102). Further, thereby, the control PC 14 determines the shape of the object 50 to be formed in the forming apparatus 12. The 3D model data can be considered, for example, as data that at least shows a three-dimensional shape. Also, in this example, the operation in step S102 is an example of the operation in the shape determination stage (shape determination process). The control PC 14 acquires 3D model data that at least includes shape data, which is data showing the shape of the object 50. Then, based on this shape data, the control PC 14 determines the shape of the object 50 to be the target of processing in subsequent operations.

[0041] Also, in this example, the 3D model data acquired by the control PC 14 can be considered, for example, as 3D data showing the object 50 to be formed in a state where the texture has not been adjusted. As such 3D model data, for example, general-purpose 3D data that does not depend on the model type, specifications, etc. of the forming apparatus 12 can be preferably used. Also, as such 3D model data, for example, data that is the same as or similar to the 3D model data used as input data in a known forming method can be preferably used. Also, the control PC 14 receives 3D model data from another computer via, for example, a network. The control PC 14 may receive 3D model data via a recording medium or the like. Also, it is conceivable that, instead of receiving the 3D model data from outside the control PC 14, the control PC 14 generates the 3D model data according to a user operation or the like. In this case, the operation of generating 3D model data in the control PC 14 can be considered as the operation of acquiring 3D model data.

[0042] Also, as described above, in the shaping device 12, for example, a shaped object 50 with a colored surface is shaped. In this case, in step S102, the control PC 14 acquires, for example, 3D model data indicating the shape and color of the shaped object 50. More specifically, in this case, the 3D model data includes, for example, shape data indicating the shape of the shaped object 50 and a texture for surface color, which is a texture indicating the color of each position on the surface of the shaped object 50. In this case, the texture for surface color is a different texture from the texture for texture adjustment described above, and indicates the color of each position on the surface of the shaped object 50 in a state where no texture adjustment is performed. As such a texture for surface color, for example, it is conceivable to use a texture indicating an image pasted on the three-dimensional shape indicated by the shape data.

[0043] Also, after acquiring the 3D model data in step S102, the control PC 14 generates a texture for texture adjustment based on the shape of the shaped object 50 (S104). In this example, the operation in step S104 is an example of the operation in the shadow data acquisition stage (shadow data acquisition process). In step S104, the control PC 14 acquires shadow data, which is data indicating the shadow generated on the surface of the shaped object 50, based on the shape data included in the 3D model data. Then, based on the shadow data, a texture for texture adjustment is generated. In this case, regarding the shadow generated on the surface of the shaped object 50, for example, it can be considered as the shadow generated on the surface of the shaped object 50 according to the shape of the shaped object 50. Regarding the shadow generated on the surface of the shaped object 50 according to the shape of the shaped object 50, for example, it can be considered as the shadow generated on the surface of the shaped object 50 according to the shape of the shaped object 50 under a predetermined ambient light. The features of the texture for texture adjustment used in this example and the operation of generating the texture for texture adjustment in step S104 will be described in more detail later.

[0044] Also, after generating the texture for texture adjustment in step S104, the control PC 14 generates the modeling data based on the 3D model data acquired in step S102 and the texture for texture adjustment generated in step S104 (S106). In this example, the operation in step S106 is an example of the operations in the surface color determination stage (surface color determination process) and the modeling data generation stage (modeling data generation process). Regarding the modeling data generated by the control PC 14 in step S106, for example, it can be considered as data indicating the shape and color of the modeled object 50 in a state where the texture has been adjusted. Also, in this example, during the operation of generating the modeling data, the control PC 14 determines the color to be used for coloring each position on the surface of the modeled object 50. In this case, the operation of determining the color to be used for coloring each position on the surface of the modeled object 50 can be considered to correspond to the operation in the surface color determination stage. Also, as described above, in step S104, the control PC 14 generates the texture for texture adjustment based on the shadow data. Therefore, regarding the operation of the control PC 14 in step S106, for example, it can be considered that the color to be used for coloring each position on the surface of the modeled object 50 is determined based on the shadow data.

[0045] Also, in this case, determining the color to be used for coloring each position on the surface of the modeled object 50 can be considered, for example, as determining the color density. Determining the color density can be considered, for example, as determining the color tone at each position. Regarding the color tone, for example, it can be considered as a grayscale tone indicating the color density of that color. Also, determining the color density can also be considered, for example, as determining the brightness of that color. Also, when performing color coloring on the surface of the modeled object 50, determining the color to be used for coloring each position on the surface of the modeled object 50 can be, for example, determining the color density for each of a plurality of colors that are the basic colors of the color representation.

[0046] Also, in this example, the control PC 14 generates modeling data indicating the shape and color of the modeled object 50 in a format that does not depend on, for example, the model type, specifications, etc. of the modeling device 12. More specifically, as described above, in this example, the control unit 110 (see FIG. 1) of the modeling device 12 generates slice data based on the modeling data. In this case, the operation of generating slice data can be considered as, for example, an operation of generating data in a format that matches the model type, specifications, etc. of the modeling device 12. Also, in this case, since the conversion to data in a format that matches the model type, specifications, etc. of the modeling device 12 is performed at the time of generating the slice data, as the modeling data generated by the control PC 14, data in a format that does not depend on the model type, specifications, etc. of the modeling device 12 can be used.

[0047] Note that in a modification of the operation of generating the modeling data, the control PC 14 may generate modeling data in a format that depends on the model type, specifications, etc. of the modeling device 12. Also, depending on the configuration, etc. of the modeling system 10 (see FIG. 1), it is also conceivable that the control PC 14 generates slice data, etc. In this case, the data used as the input data for the process of generating the slice data can also be considered as the modeling data generated in step S106, etc. Also, the slice data can also be considered as data indicating the shape and color of the modeled object 50. Therefore, it is also possible to consider the operation of generating the slice data as the operation of generating the modeling data, etc.

[0048] Also, in step S106, the control PC 14 determines the color to be used for coloring each position on the surface of the modeled object 50, for example, by generating a texture that matches the shape of the modeled object 50 indicated by the shape data included in the 3D model data acquired in step S102. In this case, it can be considered that the modeled object 50's shape and color are indicated by including this shape data and the texture in the modeling data. Regarding this texture, for example, it can be considered as a texture indicating the color to be applied to each position on the surface of the modeled object 50. Further, this texture is, for example, a texture generated separately from the texture for surface color and the texture for texture adjustment described above (hereinafter referred to as a modeling texture).

[0049] More specifically, in this example, the control PC 14 generates a texture for shaping based on the texture for texture adjustment generated in step S104. In this case, regarding the texture for shaping, for example, it can be considered that it indicates the color to be applied to each position on the surface of the shaped object 50 in the state after the texture for texture adjustment is used to adjust the texture. Further, when the 3D model data acquired in step S102 includes a texture for surface color, the control PC 14 generates a texture for shaping based on the texture for texture adjustment and the texture for surface color. Also, thereby, the control PC 14 generates a texture for shaping that reflects the color specified in the 3D model data, for example, and shows the adjusted texture. Regarding the operation of generating a texture for shaping based on the texture for texture adjustment and the texture for surface color, for example, it can also be considered as an operation of generating a texture for shaping by adjusting the texture for surface color based on the texture for texture adjustment. Also, in this example, the texture for shaping is a texture that shows an image to be pasted on the surface of the three-dimensional shape indicated by the shape data. Also, in this case, the control PC 14 generates a texture for shaping to be associated with the shape data, and based on the shape data and the texture for shaping, generates shaping data. According to this example, for example, while adjusting the texture perceived by the observer of the shaped object 50, the color to be applied to each position on the surface of the shaped object 50 can be appropriately specified. Also, thereby, for example, the shaping data can be appropriately created.

[0050] Subsequently, the characteristics of the texture for texture adjustment used in this example and the operation of generating the texture for texture adjustment in step S104 will be described in more detail. As described above, in this example, the control PC 14 acquires shadow data, which is data indicating the shadow generated on the surface of the shaped object 50, based on the shape data included in the 3D model data. Then, based on the shadow data, a texture for texture adjustment is generated. Also, in this example, the control PC 14 generates a texture for texture adjustment for adjusting translucency (translucent feeling), which is an example of texture.

[0051] Here, translucency is a texture that exists in large numbers in nature and is also an important texture related to, for example, human skin. Therefore, it is desirable to reproduce it with high quality when shaping the shaped object 50. Also, in this regard, when a human perceives translucency, for example, it can be considered that it is affected by factors such as non-specular contrast, luminance gradient in edges and thin regions, and covariance of the normal direction and shadow. Regarding non-specular contrast, for example, the high-frequency contrast in the non-specular region on the surface of an object (hereinafter referred to as the observation object) observed by a human becomes important. In this case, the high-frequency contrast in the non-specular region can be considered to be affected by, for example, the way light penetrates into detailed parts. Therefore, when the state of the high-frequency contrast in the non-specular region changes, it is considered that a change occurs in the perceived translucency (perceptual translucency). Also, in the observation object, when the light transmittance becomes high, it is considered that the contrast may be reversed or become random due to the influence of the background or the like. Similarly, the luminance gradient in edges and thin regions can also be considered to be affected by the way light penetrates. Therefore, when the luminance gradient in edges and thin regions changes, it is considered that a change occurs in the perceived translucency. Regarding the covariance of the normal direction and shadow, the normal direction can be considered to be, for example, a direction orthogonal to the surface of the observation object such as the shaped object 50. And regarding the covariance of the normal direction and shadow, for example, when the observation object is opaque, generally, it can be considered that the normal direction and shadow are covariant. Also, when this covariance is lost, it is considered that a human perceives translucency. Therefore, for example, by intentionally losing this covariance, it is considered that an observer can be made to feel translucency.

[0052] Also, as described above, in this example, a texture for texture adjustment is used to pseudo-reproduce a desired texture. And in this case, for example, by using a texture for texture adjustment that increases translucency from the above perspective, the translucency perceived by the observer can be enhanced. More specifically, in this case, for example, regarding the high-frequency contrast in the non-specular region, it is conceivable to use a texture for texture adjustment that at least partially reverses or becomes more random. Also, regarding the covariance between the normal direction and the shadow, for example, it is conceivable to use a texture for texture adjustment that causes the covariance to be lost. In this case, regarding causing the covariance between the normal direction and the shadow to be lost, for example, it can be considered that the consistency between the shape and the shadow distribution is lost. Also, as such a texture for texture adjustment, for example, it is conceivable to use a texture that makes the occluded part extremely bright and conversely makes the non-occluded part extremely dark. Also, when using such textures for texture adjustment, for example, the luminance gradient in edges, thin regions, etc. can also be made to approach a state affected by the way light enters. And in this example, considering these perspectives, for example, a texture for texture adjustment is used that determines a brightness distribution taking into account the difficulty of light reaching due to the shape of the object 50 to be modeled. Also, thereby, for example, the relative contrast generated on the surface of the object 50 is controlled to change the apparent translucency. Also, in this case, the control PC 14 generates a texture for texture adjustment by the operation shown in FIG. 3(b), for example.

[0053] FIG. 3(b) is a flowchart showing an example of an operation for generating a texture for texture adjustment. As also described above, in this example, the control PC 14 acquires shadow data, which is data indicating the shadow generated on the surface of the object 50, based on the shape data included in the 3D model data acquired in step S102. And based on the shadow data, a texture for texture adjustment is generated. More specifically, in this example, the control PC 14 generates an AO texture by computer simulation using the AO method (Ambient Occlusion method) as an example of the shadow data (S202).

[0054] In this case, for the AO texture, for example, it can be considered as a texture or the like that takes into account the shape information of the modeled object 50. Also, for the AO texture, for example, it can also be considered as data or the like that includes information regarding the shape and the degree of occlusion of the modeled object 50. For the AO texture, for example, it can also be considered as data or the like that indicates a component (ambient light component) that reflects the ambient light in a form that can be attached to the three-dimensional shape indicated by the shape data. Also, in this example, the AO texture indicates an image that is attached to the surface of the three-dimensional shape indicated by the shape data. In this case, for the image indicated by the AO texture, for example, it can be considered as an image or the like that indicates the shadow generated on the surface of the modeled object by the ambient light. Also, for the AO method, for example, it can be considered as a method or the like for calculating the influence of the ambient light from the degree of occlusion in CG technology (computer graphics technology). Regarding the generation of the AO texture, for example, it can be performed in the same or similar manner as a known method used in CG technology based on the shape data included in the 3D model data acquired in step S102. With such a configuration, for example, data used as shadow data can be automatically, easily, and appropriately acquired. Also, in this example, the AO texture is also an example of a shadow image. For the shadow image, for example, it can be considered as an image or the like that indicates the shadow generated on the surface of the modeled object 50. Also, by using such an AO texture, for example, it becomes possible to perform a luminance operation or the like that conforms to the shape in a form that can be attached to the three-dimensional shape indicated by the shape data. Also, in this example, the control PC 14 generates a grayscale image with a predetermined number of gradations (for example, about 255 gradations) as the AO texture.

[0055] Also, in this example, instead of using the AO texture as it is, as shown in the figure, processing such as tone inversion (S204), tone number limitation (S206), and gamma correction (S208) is performed on the AO texture to generate a texture for texture adjustment. In this case, regarding the tone inversion process performed in step S204, for example, it can be considered as an operation of generating an inverted image which is an image with inverted tones with respect to the AO texture. By performing tone inversion on the AO texture, for example, parts that are in the shaded portions in the AO texture can be brightened to pseudo-create the intrusion of light. Also, in this case, by generating a texture for texture adjustment based on the inverted image, for example, it becomes possible to reduce the apparent contrast of the shadow generated on the surface of the modeled object 50. Also, in this case, for example, it can be considered that the color to be colored for each position on the surface of the modeled object 50 is determined based on the inverted image.

[0056] Also, in step S206, the control PC 14 generates a tone number-limited image, which is the processed image, by limiting the tone number of the inverted image. In this case, the process of limiting the tone number can be performed in the same or similar manner as, for example, a known tone number conversion process. Also, in this example, the control PC 14 generates a tone number-limited image by performing a process of changing the inverted image to a preset tone number equal to or less than the tone number of the inverted image. In this case, regarding the tone number of the tone number-limited image, for example, it can be set to about 0.4 to 1.0 times (preferably about 0.5 to 0.9 times) the tone number of the inverted image. More specifically, regarding the tone number of the inverted image, for example, it can be made the same as the tone number of the AO texture. And, for example, when the tone number of the inverted image is 255, the tone number of the tone number-limited image can be set to about 127 to 255 tones. By generating such a tone number-limited image and generating a texture for texture adjustment based on the tone number-limited image, for example, the magnitude of the influence on the non-shaded portion can be adjusted. Also, in step S208, the control PC 14 generates a texture for texture adjustment by performing gamma correction on the tone number-limited image. In this case, the texture for texture adjustment can be considered to be, for example, an image obtained by performing gamma correction on the tone number-limited image. Also, in this case, by performing gamma correction, for the texture for texture adjustment, for example, the effect of the texture on the detailed area important for human perception can be increased.

[0057] According to this example, for example, based on the shadow generated according to the shape of the modeled object 50, a texture for texture adjustment can be appropriately generated. Further, by generating the modeling data based on the texture for texture adjustment, for example, the impression received by the observer can be appropriately changed by the shadow generated on the modeled object 50 modeled based on the modeling data. Further, thereby, for example, the texture perceived by the observer for the modeled object 50 can be appropriately changed. More specifically, in this case, by generating the texture for texture adjustment based on the inverted image, for example, the influence of the shadow generated on the surface of the modeled object 50 according to the shape of the modeled object 50 is reduced so as to be perceived by the observer, and the color for coloring each position on the surface of the modeled object 50 can be determined. Further, thereby, for example, the texture perceived by the observer for the modeled object 50 can be appropriately changed. Furthermore, by performing tone number limitation and gamma correction processing to generate the texture for texture adjustment, for example, the influence of the shadow can be changed in various ways.

[0058] Still, as described above, in this example, after generating the texture for texture adjustment based on the AO texture, a texture for modeling is further generated based on the texture for texture adjustment. Also, for the AO texture and the texture for modeling, for example, it can be considered as a texture showing an image to be pasted on the surface of the three-dimensional shape indicated by the shape data. And in this case, for the texture for texture adjustment as well, for example, it can be considered as a texture showing an image to be pasted on the surface of the three-dimensional shape indicated by the shape data. Also, in the above, for the sake of convenience of explanation, an example of the operation in the case where the tone number limit and the gamma correction are performed as separate processes has been described. However, in the operation of generating the texture for texture adjustment, for example, the tone number limit and the gamma correction may be simultaneously performed in one process. In this case, for example, by changing the pixel value in each pixel of the inverted image by a function using a parameter indicating the tone number to be limited by the tone number limit and a parameter indicating the correction amount of the gamma correction, the texture for texture adjustment is generated. Also, in this case, for example, in the flowchart shown in FIG. 3(b), it can be considered that the operation in step S206 and the operation in step S208 are executed simultaneously.

[0059] Also, in this example, as the AO texture and the texture for texture adjustment, for example, it is conceivable to generate a texture as shown in FIG. 4. FIG. 4 is a diagram for further explaining the AO texture and the texture for texture adjustment in more detail. FIG. 4(a) is a diagram showing an example of the AO texture to be generated in this example, and shows an example of the AO texture to be generated when modeling a shaped object in the shape of a dragon. In FIG. 4(a), the upper left diagram shows the shaped object without pasting the AO texture together with a predetermined background by CG. The lower left diagram shows the state where the AO texture is pasted on the shaped object in the upper left diagram. The right diagram shows the AO texture developed in a planar shape.

[0060] Also, as described above, in this example, for such an AO texture, by performing each process of tone inversion, tone number limitation, and gamma correction, a texture for texture adjustment is generated. Also, in this case, depending on the tone number limited in the tone number limitation process and the correction amount in the gamma correction, for example, as shown in FIG. 4(b), the state of the texture for texture adjustment changes. FIG. 4(b) is a diagram showing an example of the texture for texture adjustment generated in this example, and shows the shaped object with the texture for texture adjustment pasted and the developed texture for texture adjustment when the tone number limited in the tone number limitation process and the correction amount in the gamma correction are varied in various ways. More specifically, the upper left diagram in FIG. 4(b) shows an example when the tone number (R) is limited to 127 in the tone number limitation and the gamma value (γ), which is the correction amount in the gamma correction, is 1.5. The lower left diagram shows an example when the tone number (R) is limited to 127 and the gamma value (γ) is 3. The upper right diagram shows an example when the tone number (R) is limited to 255 and the gamma value (γ) is 1.5. The lower right diagram shows an example when the tone number (R) is limited to 255 and the gamma value (γ) is 3. As can be understood from these diagrams, by varying the tone number and the gamma value, the texture of the shaped object such as translucency can be varied in various ways.

[0061] Here, as described above, in this example, the control PC 14 generates modeling data in which the color of the surface is specified by a texture for modeling. Therefore, regarding the color of the surface of the object actually modeled by the modeling device 12 (see FIG. 1), it can be considered that the color is directly specified not by the texture for texture adjustment but by the texture for modeling. However, also in this case, by using the texture for modeling generated based on the texture for texture adjustment, it is possible to generate modeling data that reflects a texture as shown in FIG. 4(b), for example. More specifically, for example, when performing color coloring on the object to be modeled, in step S102 in FIG. 3(a), 3D model data including a texture for surface color and shape data is acquired. And in this case, the control PC 14 generates a texture for modeling based on the texture for texture adjustment and the texture for surface color. Further, thereby, the control PC 14 generates a texture for modeling that reflects the color specified in the 3D model data and shows the adjusted texture. Also, when not performing color coloring and making the color for coloring each position on the surface of the object to be a single color, in step S102, for example, it is conceivable to acquire 3D model data that does not include a texture for surface color and includes shape data. And in this case, for example, regarding the texture for texture adjustment, it can be considered to be used as it is as the texture for modeling. With such a configuration, for example, it is possible to appropriately generate a texture for modeling that shows the adjusted texture.

[0062] Also, when generating a texture for actual texture adjustment, regarding the number of gradations restricted by the gradation number limit and the correction amount in gamma correction, for example, it is conceivable to use values selected according to the desired texture. More specifically, for example, when attempting to represent a texture with a higher perceived translucency, it is conceivable to select the value that maximally increases the translucency regarding the number of gradations in the gradation number limit and the correction amount in gamma correction. However, it is considered that the optimal values for such the number of gradations and correction amount change depending on the shape of the modeled object and the like. Therefore, when generating a texture for texture adjustment, for example, the number of gradations restricted by the gradation number limit and the correction amount in gamma correction are used as parameters, and a plurality of types of textures may be created (generated) by making the conditions specified by these parameters different from each other. In this case, for example, a rendering image showing a state where each texture is applied to the three-dimensional shape indicated by the shape data is generated. Then, for these rendering images, an index pre-selected on an image basis is calculated, and based on the result, the texture to be used as the texture for texture adjustment is selected. With such a configuration, for example, it is conceivable to select a texture based on an index selected according to the desired texture.

[0063] More specifically, for example, when considering translucency as a texture, as described above, the texture perceived by the observer changes due to the contrast in the non-specular region and the covariance between the normal direction and the shadow. Therefore, in this case, for example, it is conceivable to select a texture using an index related to the contrast in the non-specular region (hereinafter referred to as Index 1) and an index related to the covariance between the normal direction and the shadow (hereinafter referred to as Index 2). Also, in this case, regarding Index 1, for an object with high translucency, for example, it is conceivable that the shadow is weakened and the contrast is reduced by transport under the surface. Therefore, when trying to enhance the translucency in the apparent texture, for example, it is conceivable to use a texture for texture adjustment with low contrast. And in this case, it is conceivable to calculate the contrast for the region corresponding to the modeled object (object region) in the rendering image corresponding to each of the plurality of textures to be selected, and select the texture with the lowest contrast. By doing so, for example, the translucency perceived by the observer can be appropriately enhanced. Also, in this case, for the contrast, for example, it is conceivable to calculate it by a known method such as the Michelson contrast. In this case, for example, each texture is used as the original image for which the contrast is to be calculated, and the results calculated for the luminance values (pixel values) of the original image and various spatial frequency sub-bands (for example, about 9 sub-bands) are averaged. And, for example, the texture with the minimum average value is selected.

[0064] Also, regarding Index 2, in the case of an object with high translucency, for example, it is conceivable that the consistency between the shape and the shadow distribution is lost. Therefore, when attempting to enhance the translucency in the apparent texture, it is conceivable to use a texture for texture adjustment that reduces the consistency between the shape and the shadow distribution. And in this case, for example, for the object region in the rendering image corresponding to each of the plurality of textures to be selected, it is conceivable to calculate how much the surface luminance pattern has changed compared to the opaque case, and select the texture with the largest change. By doing so, for example, the translucency perceived by the observer can be appropriately enhanced. More specifically, in this case, for example, in addition to the rendering images corresponding to each of the plurality of textures to be selected, it is conceivable to use the rendering image corresponding to the opaque case. As the rendering image corresponding to the opaque case, for example, it is conceivable to generate a rendering image showing a state where no texture is applied to the three-dimensional shape indicated by the shape data. Also, in this case, for the object region in each rendering image, for example, by dividing it into a bright part and a dark part based on the median value of the pixel values in the image, the pattern of the surface luminance is encoded. Then, for the rendering images corresponding to each of the plurality of textures to be selected, count the number of pixels with different signs compared to the rendering image corresponding to the opaque case, and select the texture with the largest number of pixels with different signs. By doing so, for example, based on a plurality of pre-selected indices, the texture to be used as the texture for texture adjustment can be appropriately selected. Also, depending on the shape of the modeled object, etc., for example, it is also conceivable that the optimal texture differs depending on the index. In this case, for example, based on a preset criterion, it is conceivable to give priority to the result of one of the indices and select the texture, etc.

[0065] Thus, in this example, for instance, based on the AO texture indicating the shadow generated on the surface of the modeled object by ambient light, a texture for texture adjustment can be appropriately generated. Also, by determining the color for coloring each position on the surface of the modeled object based on the texture for texture adjustment, the state of the modeled object can be made visible to the observer as if, for example, a shadow is being generated in a state different from the original shadow. Further, thereby, for instance, with respect to a texture such as translucency, the texture perceived by the observer can be changed. Therefore, according to this example, for instance, a modeled object expressing various textures can be appropriately modeled. Also, thereby, for instance, modeling with a desired texture or modeling a highly designed modeled object can be performed more appropriately.

[0066] Here, in this example, regarding the operation of determining the color to be used for coloring each position on the surface of the shaped object based on the texture for texture adjustment, for example, it can be considered as an operation of generating a texture different from the texture perceived in a shaped object with a uniform color at each position on the surface. More specifically, for example, the texture perceived by the observer due to the influence of the shadow generated on the surface of the shaped object by the light (e.g., ambient light) irradiated on the shaped object is defined as the perceived texture, and when the perceived texture perceived in a shaped object with a uniform color at each position on the surface is defined as the uniform color texture, regarding the operation of determining the color to be used for coloring each position on the surface of the shaped object based on the texture for texture adjustment, for example, it can be considered as an operation of determining the color to be used for coloring each position on the surface of the shaped object so that a perceived texture different from the uniform color texture is perceived by the observer. With such a configuration, for example, the texture perceived by the observer for the shaped object can be appropriately changed. Also, as can be understood from the above description and the like, as the perceived texture, for example, a texture related to translucency can be considered. In this case, in the operation of determining the color to be used for coloring each position on the surface of the shaped object based on the texture for texture adjustment, for example, the color to be used for coloring each position on the surface of the shaped object is determined so that at least a part of the translucency of the shaped object is perceived as being higher due to the perceived texture being different from the uniform color texture. With such a configuration, for example, a high translucency can be appropriately expressed as the texture of the shaped object.

[0067] Regarding the operation of generating modeling data on the control PC 14, not only the operations described above but also various modifications are possible. For example, in the above, regarding the operation of generating a texture for texture adjustment, mainly the method of using the AO texture as shadow data was described. In this case, for example, since the occlusion information can be automatically obtained, the creation of the texture for texture adjustment can be easily and appropriately automated. On the other hand, in a modified example of the operation of generating a texture for texture adjustment, for example, shadow data may be obtained by computer simulation using a method other than the AO method. In this case, for example, it is conceivable to generate a rendering image showing a state where light is irradiated under desired light source conditions on the shape indicated by the shape data included in the 3D model data, and obtain shadow data based on the rendering image. Also, depending on the quality required for the modeling, etc., for example, it is also conceivable to generate shadow data by a method of manually determining the necessary luminance for each part in the CG data and designing. In these cases as well, it is conceivable to generate, as shadow data, for example, a texture to be attached to the surface of the three-dimensional shape indicated by the shape data. Also, in this case, by appropriately performing the same or similar processing as in the case of using the AO texture using this texture instead of the AO texture, it is conceivable to generate a texture for texture adjustment. Further, in a further modified example of the operation of generating a texture for texture adjustment, shadow data may be obtained, for example, by actually measuring without relying on computer simulation. In this case, for example, it is conceivable to generate a texture for texture adjustment by the operation shown in FIG. 5.

[0068] FIG. 5 is a flowchart showing an operation of a further modification example of an operation for generating a texture for texture adjustment, and shows a modification example of the operation performed in step S104 in the flowchart shown in FIG. 3(a). In this modification example, when generating a texture for texture adjustment, a three-dimensional object for measurement is created and shadow data is acquired. More specifically, in this case, for example, based on the shape data included in the 3D model data acquired in step S102, a three-dimensional object for measurement, which is a three-dimensional object for performing measurement to acquire shadow data, is created (S212). Regarding the creation of the three-dimensional object for measurement, for example, it is conceivable to use a modeling device 12 (see FIG. 1). In this case, regarding the three-dimensional object for measurement, for example, it can be considered as a modeled object that is an intermediate product different from the modeled object to be finally modeled as the final product.

[0069] Also, regarding the three-dimensional object for measurement, for example, it can be considered as a three-dimensional object having the same shape as the modeled object to be finally modeled. And regarding the three-dimensional object for measurement, for example, it can be created with the same size as the modeled object to be finally modeled. With such a configuration, for example, the same shadow as the shadow generated according to the shape of the modeled object can be generated more appropriately. Also, depending on the accuracy required for measurement, etc., the three-dimensional object for measurement may be created with a size different from that of the modeled object to be finally modeled. In this case, for example, it is conceivable to create a three-dimensional object for measurement smaller than the modeled object to be finally modeled. With such a configuration, for example, the time, cost, etc. required for creating the three-dimensional object for measurement can be appropriately reduced. Also, regarding the three-dimensional object for measurement, it may be created by a method other than being modeled by the modeling device 12. In this case, for example, regarding the three-dimensional object for measurement, it can be considered as a three-dimensional object having the same shape as the modeled object to be finally modeled and made of a different material.

[0070] Also, in this modified example, after creating the three-dimensional object for measurement, light is irradiated onto the three-dimensional object for measurement to cause a shadow on the surface of the three-dimensional object for measurement, and the result is measured (S214). Further, based on this measurement result, shadow data is acquired. With such a configuration, for example, shadow data can be appropriately acquired with high accuracy by actual measurement. More specifically, in this case, for example, an image showing a shadow is acquired by photographing the three-dimensional object for measurement in a state where light is irradiated. Then, based on this image, shadow data is acquired. After acquiring the shadow data, for example, in a computer such as the control PC 14 (see FIG. 1), a texture for texture adjustment is generated based on the shadow data (S216). In this case, the process of generating the texture for texture adjustment based on the shadow data can be performed in the same or similar manner as when using, for example, an AO texture. More specifically, in this case, in step S214, it is conceivable to generate a texture that is attached to the surface of the three-dimensional shape indicated by the shape data as shadow data. With such a configuration, the shadow data in this modified example can be handled in the same or similar manner as, for example, an AO texture. Further, thereby, the operation of generating the texture for texture adjustment in step S216 can be performed in the same or similar manner as when using an AO texture.

[0071] Also in this modified example, for example, a texture for texture adjustment can be appropriately generated. Further, thereby, for example, the texture of the modeled object in appearance can be appropriately changed. In this case, by changing the light source conditions for irradiating the three-dimensional object for measurement in step S214, shadow data can be appropriately acquired with high accuracy according to various light source conditions. In a further modified example of the operation of generating the texture for texture adjustment, the shadow data may be acquired in a form other than a texture. In this case, in step S216, a texture for texture adjustment is generated based on the shadow data in a form other than a texture.

[0072] In a further modification of the operation of generating the texture for texture adjustment, for example, without creating a three-dimensional object for measurement, it is also conceivable to obtain shadow data based on the results of measurements performed using an existing three-dimensional object. More specifically, as the modeling data, it is also conceivable to create data indicating an existing three-dimensional object, such as a building or an object that has existed since before the start of creating the modeling data. And in such a case, even without separately creating a three-dimensional object for measurement, shadow data can be obtained by using the existing three-dimensional object. In this case, in the operation of obtaining shadow data, for example, shadow data is obtained based on the shadows generated on the surface of the existing three-dimensional object. Also, in this case, for example, the operation of step S212 in the flowchart shown in FIG. 5 is omitted, and an existing three-dimensional object is used instead of the three-dimensional object for measurement, and the same or similar operations as the operations after step S214 are performed to obtain shadow data. Also, based on the shadow data obtained in this way, a texture for texture adjustment is generated. Even in such a configuration, for example, shadow data can be appropriately obtained with high accuracy. Also, thereby, for example, a texture for texture adjustment can be appropriately generated.

[0073] Also, as the modeling data, it is also conceivable to create data indicating a modeled object that is smaller in size than an existing three-dimensional object, such as a miniature. In this case, regarding the operation of obtaining shadow data using an existing three-dimensional object, for example, it can also be considered as an operation of obtaining shadow data using a three-dimensional object that is larger in size than the modeled object to be modeled. Also, as the existing three-dimensional object, as described above, it is also conceivable to use a three-dimensional object that is particularly large in size, such as a building. And in this case, for example, when trying to irradiate light on the three-dimensional object using a lighting device or the like, it may cost a large amount. Therefore, in such a case, for example, shadow data may be obtained based on the shadows generated on the surface of the three-dimensional object by natural light such as sunlight. If configured in this way, for example, shadow data indicating the shadows generated on the surface of the three-dimensional object under the light source conditions corresponding to natural light can be appropriately obtained.

[0074] In addition, in the above description, mainly the point of changing the appearance texture of the modeled object using a texture for texture adjustment was explained. However, depending on the configuration of the modeled object, it is also possible to change the actual texture of the modeled object using a part of the modeled object. In this case, by changing the actual texture of the modeled object while changing the appearance texture of the modeled object using a texture for texture adjustment, the texture perceived by the observer can be changed more appropriately. Also, in this case, for example, it is conceivable to model a modeled object having a scattering region 156 (see FIG. 2) as in the modification example described above using FIG. 2(b). More specifically, in this case, for example, it is conceivable to use the scattering region 156 having the configuration shown in FIG. 6.

[0075] FIG. 6 is a diagram for explaining in more detail a modification example of the modeled object 50, and shows an example of the configuration of the scattering region 156 in the case of modeling the modeled object 50 having the scattering region 156. FIG. 6(a) is a diagram showing an example of the configuration of the modeled object 50 having the scattering region 156, and shows an example of the detailed configuration of the scattering region 156 in the modeled object 50 shown in FIG. 2(b) together with the light reflection region 152 and the coloring region 154. Also, in FIG. 6(a), for the sake of illustration, the overlapping manner of the regions in the normal direction orthogonal to the surface of the modeled object 50 is shown in a simplified manner for a part of the modeled object 50. In this modification example, the modeled object 50 includes a light reflection region 152, a scattering region 156, and a coloring region 154. The scattering region 156 is a region formed using white ink and clear ink, and is formed between the light reflection region 152 and the coloring region 154. In this case, as also explained above, the coloring material contained in the white ink can be considered as an example of a scattering body. Also, in this modification example, the scattering region 156 is a region in which the amount of the scattering body contained per unit volume is made different depending on the position by varying the usage ratio of the white ink. In this case, the usage ratio of the white ink can be considered, for example, as the ratio of the amount of white ink used per unit volume when forming the scattering region 156. Also, for this ratio, for example, it can be considered as the ratio of the amount of white ink used to the total amount of the amount of white ink used and the amount of clear ink used.

[0076] More specifically, in this modified example, the scattering region 156 has a plurality of regions 162a to 162e with different usage ratios of white ink. Each of the plurality of regions 162a to 162e is a region with different positions in a plane parallel to the surface of the shaped object 50, and is formed using white ink and clear ink. In this case, a part of the plurality of regions 162a to 162e may be formed using only white ink or only clear ink. When configured in this way, by forming the scattering region 156 using white ink and clear ink, for example, in the scattering region 156 under the colored region 154, light can be scattered to exhibit translucency. Also, thereby, for example, the actual texture of the shaped object 50 can be appropriately changed. Therefore, according to this modified example, for example, appropriately combining changing the apparent texture of the shaped object using a texture for texture adjustment and varying the actual texture of the shaped object 50 by the scattering region 156 can be achieved. Also, in this case, in each of the plurality of regions 162a to 162e, by making the usage ratios of white ink different from each other, a difference will occur in the way of scattering with respect to light incident from the outside through the colored region 154. Also, as a result, a difference in texture will occur at positions where each of the plurality of regions 162a to 162e overlaps in the colored region 154. Therefore, according to this modified example, for example, the texture perceived by an observer for the shaped object 50 can be changed in a more diverse manner.

[0077] Also, in this modified example, regarding the texture perceived by the observer, it can be considered that it is caused by, for example, combining the effect of using the texture for texture adjustment and the effect of using the scattering region 156 having the regions 162a to e. And in this case, in order to change the texture more appropriately, for example, it can be considered to form each of the plurality of regions 162a to e at positions according to the image shown by the texture for texture adjustment. Further, as a method therefor, regarding the way of forming the scattering region 156, for example, it can be considered to determine it based on shadow data such as AO texture. More specifically, in this case, in the operation of generating the modeling data in the control PC 14 or the like, for example, based on the shadow data, the usage ratio of white ink for each position of the scattering region 156 is determined. With such a configuration, for example, the modeling data showing the modeled object 50 including the scattering region 156 as described above can be appropriately generated. Also, in this case, regarding the determination of the usage ratio of white ink for each position of the scattering region 156, for example, it can be considered to determine the amount of scatterers included per unit volume at each position of the scattering region 156 and the like.

[0078] Also, in the case of the shaped object 50 of this modification example, the light reflection region 152 formed using white ink can also be considered as a region that scatters light. In this regard, in this modification example, for the light reflection region 152, for example, unlike the scattering region 156, it can be considered that the usage ratio of white ink at each position is constant. Also, as a result, for the light reflection region 152, for example, unlike the scattering region 156, it can be considered as a region that scatters light uniformly. More specifically, for the light reflection region 152, for example, it can be considered to be formed only with white ink. Also, for the light reflection region 152, for example, it can also be considered as a region formed using an amount of white ink that makes the region opaque. In a further modification example of the configuration of the shaped object 50, the light reflection region 152 may be formed using white ink and clear ink. Also in this case, in the light reflection region 152, for example, it is conceivable to make the usage ratio of white ink at each position constant. Also, in a further modification example of the configuration of the shaped object 50, for the scattering region 156 as well, it is conceivable to make the usage ratio of white ink at each position constant. In this case, for the scattering region 156, for example, it can be considered as a region using white ink at a usage ratio less than that of the light reflection region 152.

[0079] Also, in a further modification example of the configuration of the shaped object 50, for example, as shown in FIG. 6(b), it is also conceivable to form a scattering region 156 having a plurality of layers 172. FIG. 6(b) is a diagram showing another example of the configuration of the shaped object 50 including the scattering region 156, and shows a simplified view of the overlapping manner of regions in the normal direction orthogonal to the surface of the shaped object 50 for a part of the shaped object 50. In this modification example, the scattering region 156 has a plurality of layers 172 that overlap in the normal direction of the shaped object 50. In this case, for each layer 172, for example, it can be considered as a layer-like region that spreads along the surface shape of the shaped object 50. Also, in this modification example, each layer 172 is formed using white ink and clear ink. In this case, for each layer 172, for example, it can also be considered as a translucent region formed by making the usage amount of white ink per unit volume less than that of the light reflection region 152.

[0080] Also, for each of the plurality of layers 172 in the scattering region 156, for example, it is conceivable to form them by varying the usage ratio of white ink from one another. In this case, for the scattering region 156, for example, it can be considered that a plurality of layers 172 with different light scattering manners overlap in the normal direction of the shaped object 50. By forming the scattering region 156 with such a configuration, for example, the light scattering manner in the scattering region 156 can be varied in various ways. Also, thereby, for example, the texture of the shaped object 50 can be varied in a more diverse manner. Also, in this case, for the plurality of layers 172, it is also conceivable to form them by gradually changing the usage ratio of white ink according to the order of overlapping in the normal direction. In this case, for the scattering region 156, for example, it can be considered that it becomes a region where the characteristics change in a gradation manner with the layer 172 as a unit. If configured in this way, for example, in the shaped object 50, more diverse textures can be expressed. More specifically, in this case, for example, the usage ratio of white ink in the layer 172 closest to the light reflection region 152 is made the largest, and the usage ratio of white ink is gradually decreased as the distance from the light reflection region 152 increases. Conversely, for example, the usage ratio of white ink in the layer 172 closest to the light reflection region 152 is made the smallest, and the usage ratio of white ink is gradually increased as the distance from the light reflection region 152 increases, etc. are also conceivable. Also, among the plurality of layers 172 included in the scattering region 156, at least some of the layers 172 may be formed in a configuration having a plurality of regions 162, such as the scattering region 156 having the configuration shown in FIG. 6(a). If configured in this way, for example, in the shaped object 50, more diverse textures can be expressed.

[0081] Next, supplementary explanations and the like regarding each configuration described above will be given. In the following, for convenience of explanation, including the modification examples and the like described above, this will be referred to as this example. In the field of 3D modeling (3D printing), for example, in a configuration using the scattering region 156 described above, if a configuration that actually changes physical properties such as the scattering phenomenon is used, a texture such as translucency can be expressed. However, in this case, depending on the properties of the modeling material and the like, the range of textures that can be expressed may be narrowed. On the other hand, the inventor of the present application focused on the fact that the factors by which humans perceive textures such as translucency do not necessarily depend on physical phenomena (such as the scattering phenomenon). Also, based on this viewpoint, it was considered to change the apparent texture of the modeled object by using a texture for texture adjustment in which the pixel value (luminance value) is controlled in accordance with the clue for perceiving the texture. In this case, regarding the texture for texture adjustment, for example, it can be considered that it is created based on the concept of reproducing the clue by which humans perceive textures such as translucency.

[0082] Also, in this case, regarding the method used in this example, for example, by reproducing the features related to the texture in the texture, it can be considered that the texture perceived by the observer is changed in an illusory way. More specifically, in this case, for example, for a modeled object modeled in a configuration where scattering indicating translucency does not actually occur, by reproducing the features related to the perception of translucency in the texture for texture adjustment, apparent translucency is expressed. With such a configuration, for example, even when a region (scattering region 156) for changing the physical scattering state is not formed, as in the modeled object having the configuration shown in FIG. 2(a), translucency can be appropriately expressed. Also, in this case, for example, as in the modeled object having the configuration shown in FIG. 2(b), if the scattering region 156 is further used, the translucency can be enhanced. Also, in this case, for example, by using the scattering region 156 in which the scattering method varies depending on the position, it is also possible to perform special appearance expressions and the like.

[0083] In addition, the inventor of the present application confirmed, through an evaluation experiment, that the texture perceived by an observer changes by the method described above. More specifically, the inventor of the present application formed shaped objects under various conditions by combining a plurality of different types of shapes with a plurality of different textures for texture adjustment. Then, by evaluating the state of each shaped object using a subjective evaluation method in which a plurality of subjects participate, it was confirmed that there are significant changes in texture such as translucency due to the influence of the texture for texture adjustment, etc.

Industrial Applicability

[0084] The present invention can be suitably used, for example, in a method for creating modeling data, etc.

Explanation of Reference Numerals

[0085] 10... Modeling system, 102... Head part, 104... Modeling table, 106... Scanning drive part, 110... Control part, 12... Modeling device, 14... Control PC, 152... Light reflection area, 154... Coloring area, 156... Scattering area, 162... Area, 172... Layer, 202... Inkjet head, 204... Ultraviolet light source, 206... Flattening roller, 50... Shaped object, 52... Support layer

Claims

1. A method for creating modeling data that creates modeling data which is data indicating an object to be modeled by a modeling apparatus, the method comprising: a shape determination step of determining the shape of the object; a shadow data acquisition step of acquiring shadow data which is data indicating a shadow generated on the surface of the object according to the shape of the object; and a surface color determination step of determining a color for coloring each position on the surface of the object based on the shadow data. The method for creating modeling data according to claim 1, characterized by comprising the above steps.

2. In the shadow data acquisition step, a shadow image which is an image indicating a shadow generated on the surface of the object is acquired as the shadow data; The method for creating modeling data according to claim 1, characterized in that, in the surface color determination step, a color for coloring each position on the surface of the object is determined based on an inverted image which is an image obtained by performing tone inversion on the shadow image.

3. The method for creating modeling data according to claim 2, characterized in that, in the surface color determination step, based on the inverted image, a color for coloring each position on the surface of the object is determined such that the influence of a shadow generated on the surface of the object according to the shape of the object is reduced and perceived by an observer.

4. When a perceived texture which is perceived by an observer due to the influence of a shadow generated on the surface of the object by light irradiated on the object is defined as a perceived texture, and a uniform color texture which is the perceived texture perceived in the object in which the color of each position on the surface is made uniform is defined, The method for creating modeling data according to claim 1, characterized in that, in the surface color determination step, a color for coloring each position on the surface of the object is determined such that a perceived texture different from the uniform color texture is perceived by an observer.

5. The perceived texture is a texture related to translucency; The method for creating modeling data according to claim 4, characterized in that, in the surface color determination step, a color for coloring each position on the surface of the object is determined such that at least a part of the translucency in the object is perceived to be higher due to the fact that the perceived texture is different from the uniform color texture.

6. In the shape determination step, the shape of the object is determined based on shape data which is data indicating the shape of the object; The method for creating modeling data according to claim 1, characterized in that, in the surface color determination step, a texture to be pasted on the surface of the three-dimensional shape indicated by the shape data is generated.

7. Further comprising a modeling data generation step of generating the modeling data based on the shape data and the texture, In the modeling data generation step, the modeling data showing the modeled object is generated, the modeled object including a scatterer which is an inclusion having a property of scattering light, and including a scattering region in which the amount of the scatterer included per unit volume varies depending on the position. The method for creating modeling data according to claim 6, characterized in that

8. In the modeling data generation step, the modeling data showing the modeled object including the scattering region is generated by determining the amount of the scatterer included per unit volume at each position in the scattering region based on the shadow data. The method for creating modeling data according to claim 7, characterized in that

9. In the shadow data acquisition step, the shadow data is acquired by computer simulation using the AO method (Ambient Occlusion method). The method for creating modeling data according to any one of claims 1 to 8, characterized in that

10. In the shadow data acquisition step, a three-dimensional object having the same shape as the shape determined in the shape determination step is created, and the shadow data is acquired based on the shadow generated on the surface of the three-dimensional object by irradiating the three-dimensional object with light. The method for creating modeling data according to any one of claims 1 to 8, characterized in that

11. The modeling data is data showing an existing three-dimensional object, In the shadow data acquisition step, the shadow data is acquired based on the shadow generated on the surface of the existing three-dimensional object. The method for creating modeling data according to any one of claims 1 to 8, characterized in that

12. A modeling data generation device for generating modeling data which is data showing a modeled object to be modeled by a modeling device, A shape determination process for determining the shape of the modeled object, A shadow data acquisition process for acquiring shadow data which is data showing a shadow generated on the surface of the modeled object according to the shape of the modeled object, And a surface color determination process for determining a color for coloring each position on the surface of the modeled object based on the shadow data And performing to generate the modeling data. A modeling data generation device characterized in that

13. A modeling device for modeling a modeled object, The modeling data generation device according to claim 12, And a modeling device for modeling the modeled object based on the modeling data generated by the modeling data generation device A modeling system characterized by comprising

Images