JP4254543B2 - Design development support apparatus and support method - Google Patents

Description

  The present invention relates to a technique for supporting a process until a painted surface intended by a designer is actually obtained, and obtaining the intended painted surface in a short period of time.

  The painting is roughly classified into a solid paint mainly composed of a color pigment and a metallic paint mainly composed of a color pigment and a glittering material. The painted surface with solid paint appears to have a nearly constant color regardless of changes in the light source position and the viewpoint position.

  On the other hand, the visible color of the painted surface to which the metallic paint is applied varies depending on the light source position and the viewpoint position.

  For example, an object whose outer surface is curved, such as an automobile, changes the angle with respect to the light source and the angle with respect to the viewpoint depending on the position of the outer surface. For this reason, even if one kind of metallic paint is applied to the entire surface, the color that appears on the object surface is not uniform, the color varies depending on the position, and a color distribution appears on the object surface. The designer assumes the color distribution that appears on the surface of the object, and determines the color distribution to be displayed.

  The color distribution that appears on the object surface is determined by the paint. The color distribution that appears on the surface of the object changes by changing the type and composition of the color pigment and the glittering material. Therefore, it is necessary to design a paint that gives the color distribution that the designer wants to appear.

  For example, Japanese Patent Laid-Open No. 2003-281565 measures the tendency of a human to perceive glossiness by subjective evaluation experiments, changes the surface reflection component based on the iso-glossiness curve obtained from the subjective evaluation experiments, and gloss Disclose that the feeling can be reproduced.

JP 2003-281565 A

  At present, the designer tells the paint designer the color distribution he wants to appear, and the paint designer designs the paint based on that information. A prototype paint designed by the paint designer is applied to the specimen and provided to the designer. The designer observes the test painted surface and feeds back the difference from the desired painted surface to the paint designer. In order to repeat this cycle, the period until the painted surface intended by the designer is actually obtained becomes longer.

  In particular, there is no tool to accurately describe the paint surface intended by the designer, including the glitter due to the reflection characteristics of the glitter material, and the feedback frequency is often used to provide feedback with words that indicate sensations such as “more glare”. Tend to be more. As a result, product shipment may begin before the painted surface intended by the designer is obtained. In addition, the design intended by the designer may not be sufficiently transmitted, and the intended design may not be obtained.

  Therefore, in the present invention, the period of time until the intended painted surface is obtained is shortened by changing the instruction information transmitted to the paint designer from the expression belonging to the sensibility to the objective expression. In addition, the design intended by the designer will be realized with high accuracy, and colors with higher added value will be created.

  The present invention relates to a reflectance storage means for storing an initial value of a variable angle spectral reflectance of a painted surface, a glitter particle data storage means for storing an initial value of the glitter particle data of the painted surface, and an object. Illuminated with the light source from the angle distribution storage means storing the angle distribution of the surface, the assumed light source position, the assumed viewpoint position, and the angle distribution stored in the angle distribution storage means. The variable angle distribution calculating means for calculating the variable angle distribution on the object surface when observing the object from the viewpoint, the variable angle distribution calculated by the variable angle distribution calculating means, and the reflectance storage means Color distribution of the object surface obtained when observing the object illuminated by the light source from the viewpoint based on the variable spectral reflectance and the glitter particle data stored in the glitter particle data storage means Color distribution calculator to calculate Display of the color distribution calculated by the color distribution calculation means and display means for displaying the glitter particle property data used in the color distribution calculation means; correction means for correcting the glitter particle property data; and the display Means for changing the color distribution display displayed on the apparatus to a color distribution calculated from the corrected glitter particle data.

  The glitter particle property data of the present invention includes a plurality of light luminance levels representing light luminance in a predetermined area and a ratio of the number of unit areas of each light luminance level in the predetermined area.

  The correcting means of the present invention is characterized in that the light luminance level or / and the ratio are corrected.

  According to the present invention, the display unit further displays a graph of the variable angle spectral reflectance corresponding to the color distribution display, and the correcting unit corrects the variable angle spectral reflectance displayed in the graph on the display device, Means for updating the storage contents of the reflectance storage means to the corrected variable angle spectral reflectance, and the color distribution display displayed on the display device, the corrected variable spectral reflectance and the initial or corrected And means for changing to a color distribution calculated from the glitter particle data.

In addition, the present invention provides a light source based on a process of assuming a variable spectral reflectance of the painted surface, a process of assuming glitter particle data of the painted surface, an angle distribution of the object surface, a position of the light source, and a position of the viewpoint. From the process of calculating the angle distribution of the object surface obtained when observing the illuminated object from the viewpoint, the calculated angle distribution, the assumed angle difference spectral reflectance, and the glitter particle data, A step of calculating a color distribution of an object surface obtained when observing an illuminated object from a viewpoint, a step of displaying the calculated color distribution on a display device , a step of correcting glitter particle data, and a display device And a step of changing the color distribution display displayed in (1) to a color distribution calculated from the modified glitter particle data.

  The glitter particle property data of the present invention includes a plurality of light luminance levels representing light luminance in a predetermined area and a ratio of the number of unit areas of each light luminance level in the predetermined area.

  The step of correcting the glitter particle property data of the present invention is characterized by correcting the light luminance level or / and the ratio.

  According to the present invention, design development support including glitter particles that cannot be specified only by a spectral reflectance curve is possible, so that it is possible to provide advanced development support for a paint color containing a glitter material.

  FIG. 1 shows a design development support apparatus 10 according to this embodiment. The design development support device 10 includes a computer 20, a display 40 (display device), a keyboard 50 for inputting data, a mouse 52, and an optical disk drive 54.

  The computer 20 includes a CPU 22, a data storage unit 24, a program storage unit 26, an input / output port 28, a display driver 30, and the like.

  The display 40 is connected to the display driver 30 of the computer 20. The display driver 30 converts a signal input from the input / output port 28 into an image display signal and outputs the image display signal to the display 40. The display 40 displays a color image according to the input image display signal.

  The keyboard 50, mouse 52, and optical disk drive 54 are connected to the input / output port 28 of the computer 20. Data input and design to the design development support apparatus 10, operation of the design development support apparatus 10, and the like are performed by these input devices.

  The data storage unit 24 stores variable-angle spectral reflectance data 60 describing the variable-angle spectral reflectance of the painted surface, bright particle property data 62, and CAD data 64 describing the shape of the automobile body.

  Next, the variable angle spectral reflectance data 60 describes the variable angle spectral reflectance of the paint. The variable angle spectral reflectance is a spectral reflectance obtained by changing the angle with respect to the regular reflection direction in colorimetry of the object surface. The angle formed by the observation direction with respect to the regular reflection direction is called a variable angle. That is, the variable spectral reflectance reflects the spectral reflectance measured for each variable angle. Here, the variable angle will be described with reference to FIG. FIG. 2 shows a state in which light is incident on the painted surface 12 from the light source 14. The incident direction is indicated by an arrow 16. At this time, the regular reflection direction on the coating surface 12 is indicated by an arrow 18 in FIG. When the reflected light of the painted surface is observed in the direction indicated by the arrow 19 in FIG. 2, the angle θ formed by the regular reflection direction indicated by the arrow 18 and the observation direction indicated by the arrow 19 is a variable angle.

  The variable angle spectral reflectance of the painted surface is obtained by measuring the painted surface to which an existing paint is applied with a variable angle spectral reflectance measuring device or the like. As the variable angle spectral reflectance measuring apparatus, for example, a variable angle spectral reflectance system manufactured and marketed by the generally known “Murakami Color Research Laboratory Co., Ltd.” can be used.

  3 and 4 show the configuration of the variable angle spectral reflectance measuring apparatus 100 as a specific example. As shown in FIGS. 3 and 4, the variable angle spectral reflectance measuring apparatus 100 mainly includes a light source 102 and a light receiving element 104. The variable angle spectral reflectance measurement apparatus 100 irradiates the sample 106 with illumination light emitted from the light source 102, changes the observation direction of the light receiving element 104, and reflects each reflected light received from a plurality of observation directions. Spectral reflectance is measured to obtain variable angle spectral reflectance. Here, the sample 106 is made of a metallic bright material (for example, aluminum flake pigment, metal-plated glass flake pigment, plate-like iron oxide pigment, graphite, etc.) and / or mica-based bright material (for example, white mica, interference mica, It is a plate-like painted surface (for example, metal plate, plastic plate) having a predetermined area to which a paint color including colored mica is applied.

  3 and 4 show that the illumination light emitted from the light source 102 of the variable angle spectral reflectance measurement apparatus 100 is incident from the incident direction 103 at an angle θ1. The specular reflection direction at the sample 106 at this time is indicated by an arrow 110 having the same angle as θ1 across the sample normal 108. When the reflected light of the sample 106 is observed from the direction indicated by the broken line 112, the angle θ2 formed by the sample normal 108 and the observation direction indicated by the broken line 112 is the light reception angle. Further, the angle θ3 formed by the observation direction indicated by the broken line 112 and the regular reflection direction indicated by the arrow 110 is a variable angle. The light receiving angle θ <b> 2 and the variable angle θ <b> 3 change by moving the observation direction of the light receiving element 104.

  3 shows the case where the variable angle θ3 is 30 degrees (incident angle θ1 is 60 degrees and the light receiving angle θ2 is 30 degrees), and FIG. 4 shows the case where the variable angle θ3 is 120 degrees (incident angle θ1 is 60 degrees). , When the light receiving angle θ2 is −60 degrees). In the present embodiment, the spectral reflectance of the variable angle θ3 for each degree is acquired using the light receiving element 104 while changing the variable angle θ3 by 1 degree from 30 degrees to 120 degrees.

  FIG. 5 shows an example of the variable angle spectral reflectance obtained as described above. The measurement conditions here are a wavelength of 410 to 730 nm, a light receiving angle θ2 of 30 to −60 degrees (a variable angle θ3 of 30 degrees to 120 degrees). The variable spectral reflectance is obtained by an existing predetermined function of the variable angle and the wavelength. As shown in FIG. 3, the largest spectral reflectance is obtained when the light receiving angle θ2 is the maximum 30 degrees (when the variable angle θ3 is the minimum 30 degrees), and as shown in FIG. It can be seen that the smallest spectral reflectance is obtained when θ2 is the minimum −60 degrees (when the variable angle θ3 is the maximum 120 degrees).

  The glitter particle data 62 describes the brightness information of the glitter material-containing paint. The light luminance information is information relating to the light luminance in a predetermined region on the painted surface at a predetermined incident angle and variable angle.

  Here, the light luminance information and the acquisition method thereof will be specifically described. The light luminance information can be acquired using the light luminance measuring apparatus 200 shown in FIG. The light luminance measuring apparatus 200 measures the light luminance of the sample coated with the paint color of the glittering material-containing paint with a camera, acquires image data, and calculates the light luminance.

  More specifically, as shown in FIG. 6, the light luminance measuring apparatus 200 mainly includes a light source 202, a CCD (Charge Coupled Device) camera 204, a computer 206 connected to the CCD camera, and the like. The light intensity measuring device 200 irradiates the same sample 106 whose angle-change spectral reflectance is measured by the angle-change spectral reflectance measurement device 100 with illumination light emitted from the light source 202 in the incident direction 203. The sample 106 is photographed by the CCD camera 204 from the observation direction 210 that is not the specularly reflected light indicated by the arrow 208, and image data is acquired. In the present embodiment, photographing is performed with the incident angle θ4 fixed at 25 degrees, the light receiving angle θ5 fixed at 10 degrees, and the variable angle θ6 fixed at 15 degrees.

  The acquired image data is transmitted to the computer 206, and the light intensity is calculated by the computer 206. The image data acquired as described above is illustrated in FIGS. An example in which image data of two 9 mm × 9 mm samples is decomposed into 512 × 512 pixels is shown. FIG. 7 is an example of image data of a silver metallic sample that is sensory-evaluated as “glaring”, and FIG. 8 is an example of image data of a silver metallic sample that is sensory-evaluated as “dense”.

  The light luminance for each pixel is calculated from such image data, and the variance of the light luminance is calculated for each pixel. The variance of the light intensity is calculated by performing histogram processing on the acquired light intensity for each pixel. Examples of histograms are shown in FIGS. 9 and 10. FIG. 9 is a histogram of light intensity for each pixel based on the image data of FIG. In FIG. 7, since the portions where the light luminance is extremely high are scattered, the dispersion is uneven in FIG. On the other hand, FIG. 10 shows a histogram of the light intensity for each pixel based on the image data of FIG. In FIG. 8, since the light luminance is uniform, it can be seen that in FIG. 10, the dispersion is narrow and symmetrical with respect to the average.

  Based on the calculated distribution of light luminance, the ratio of the number of pixels for each light luminance level is calculated. First, the classification of the light luminance level in the present embodiment will be described. For example, when a histogram as shown in FIG. 11 is obtained for a certain sample, the average of the light luminances totaled by the total number of pixels is calculated as A. B is a point for classifying pixels having a high light luminance level equal to or higher than the average light luminance A into two, and is represented by A + α. Here, the value of α can be arbitrarily set, and may be set to a predetermined fixed value or a coefficient that varies with the value of A. In this embodiment, α is set to a fixed value of A + 1500. Is set. These light intensities A and B are key values for determining the light intensity ratio for each light intensity level described below, and in particular, the determination method of B is important for accurately expressing the glitter particle property. With the light intensities A and B calculated in this way as thresholds, X below A is a color material main part, Y above A and B is a bright material main part, and Z above B is a high bright material main part. Sort by brightness level. The ratio of the number of pixels is the ratio of the number of pixels belonging to the color material main portion X to the sample area in the portion surrounded by the histogram curve and the horizontal axis in FIG. It is obtained by calculating the ratio of the number of pixels in the sample area belonging to Y and the ratio of the number of pixels in the sample area belonging to the high glitter material main body Z. In the present embodiment, as shown on the right side of FIG. 12, the ratio of X is calculated to be 60%, the ratio of Y to 35%, and the ratio of Z to 5%.

  Subsequently, the ratio of the light intensity for each light intensity level is calculated. This light luminance ratio is for correcting the variable angle spectral reflectance of each pixel classified by the ratio of the number of pixels for the color display of the automobile body described by the CAD data 64, and based on the values of A and B. Calculated as First, as shown in FIG. 11, an average light luminance c of pixels belonging to a color material main part X of A or less is calculated, and an average of light intensity of pixels belonging to a bright material main part Y of A or more and B or less is calculated. The light intensity d is calculated, and the average light intensity e of the light intensity of the pixels belonging to the high glitter material main body Z equal to or greater than B is calculated. Then, as shown on the left side of FIG. 12, the light luminance ratio with respect to the average light luminance A of all the pixels can be calculated. In this embodiment, the light luminance ratio of c / A is calculated as 0.8, the light luminance ratio of d / A is 1.2, and the light luminance ratio of e / A is calculated as 2.0.

  Next, the ratio of the light luminance for each light luminance level is calculated. This light luminance ratio is obtained by correcting the variable angle spectral reflectance of each pixel classified by the pixel number ratio for CG, and is calculated based on the values of A and B. First, as shown in FIG. 11, an average light luminance c of pixels belonging to a color material main part X of A or less is calculated, and an average of light intensity of pixels belonging to a bright material main part Y of A or more and B or less is calculated. The light intensity d is calculated, and the average light intensity e of the light intensity of the pixels belonging to the high glitter material main body Z equal to or greater than B is calculated. Then, as shown on the left side of FIG. 12, the light luminance ratio with respect to the average light luminance A of all the pixels can be calculated. In this embodiment, the light luminance ratio of c / A is calculated as 0.8, the light luminance ratio of d / A is 1.2, and the light luminance ratio of e / A is calculated as 2.0.

  As described above, the light luminance information is calculated and stored in the data storage unit 24 as the glitter particle data 62.

  Returning to the description of FIG. 1, the CAD data 64 describes the shape of the automobile body in three dimensions. By processing the CAD data 64, it is possible to know the angular distribution of the automobile body surface. If the vehicle is designed by 3D CAD or the like, the CAD data may be used. Alternatively, shape data obtained by measuring an existing automobile body shape with a three-dimensional measuring device or the like may be created as CAD data.

  The variable spectral reflectance data 60, the glitter particle data 62, and the CAD data 64 are taught to the computer 20 using the keyboard 50, mouse 52, or optical disk drive 54. The computer 20 stores the taught data in the data storage unit 24.

  The program storage unit 26 stores a CAD program 70, a variable angle distribution calculation program 72, a color distribution calculation program 74, an image display program 76, a variable angle spectral reflectance calculation program 78, and a bright particle property correction program 80. These programs 70 to 80 are used for arithmetic processing of the CPU 22.

  The CAD program 70 processes the CAD data 64 describing the vehicle body shape, calculates the angle indicating the normal direction at each position on the surface of the vehicle body, and generates angle distribution data describing the angle distribution of the vehicle body surface. create.

  The variable angle distribution calculation program 72 calculates the variable angle at each position on the surface of the vehicle body when observing the vehicle body illuminated with the light source from the generated angle distribution data and the position of the light source and the viewpoint. calculate. The position of the light source and the viewpoint can be specified by the designer. Then, the angle distribution data describing the angle distribution on the surface of the automobile body is created.

  The color distribution calculation program 74 creates color distribution data describing the color distribution on the surface of the automobile body from the created variable angle distribution data, variable angle spectral reflectance data 60, and glitter particle data 62. This color distribution data is a color distribution obtained when an object illuminated with a previously specified light source is observed from a previously specified viewpoint.

  The image display program 76 processes the color distribution data to display the color distribution of the car body surface on the display 40. Further, the image display program 76 performs a process of gradation-displaying a change in color corresponding to a change in the angle of change of the painted surface described by the angle-change spectral reflectance data 60.

  The variable angle spectral reflectance calculation program 78 allows the designer to modify the variable angle spectral reflectance data 60. Further, the variable spectral reflectance data 60 is complementarily corrected based on the designer's correction. Then, the variable angle spectral reflectance data 60 stored in the data storage unit 24 is updated to the variable angle spectral reflectance data 60 that has been complementarily corrected.

  The glitter particle property modification program 80 allows the designer to modify the glitter particle property data 62.

  Hereinafter, the operation procedure of the design development support apparatus 10 will be described with reference to the flowchart of FIG.

  First, the distorted spectral reflectance data 60 of the painted surface is read from the data storage unit 24 as an initial value (S10). At this time, as the variable spectral reflectance data 60 read as the initial value, it is preferable to select data having a color close to that of the painted surface that the designer intends to develop from the existing modified spectral reflectance data of the painted surface.

  In this embodiment, the description using the CIE 1976 (L * a * b *) color system is used to describe the variable angle spectral reflectance data of the painted surface. In the CIE 1976 (L * a * b *) color system, colors are represented by L * values, a * values, and b * values. The L * value describes the lightness of the color. That is, the larger the L * value, the brighter the color. The a * value describes the hue of the color and its intensity, in particular the intensity for the red and green hues. The higher the a * value is, the greater the positive value is, and the more the hue is red, and the smaller the a * value is, the smaller the color is green. The b * value describes the hue of the color and its intensity, and in particular describes the intensity for the yellow and blue hues. The larger the b * value is, the larger the positive hue is, and the yellow hue becomes. The smaller the b * value is, the smaller the blue hue is. The c * value calculated from the a * value and the b * value describes the saturation of the color. Note that c * = (a * ^ 2 + b * ^ 2 +) ^ 1/2.

  Subsequently, the glitter particle data 62 of the painted surface is read from the data storage unit 24 as an initial value (S20). At this time, if the variable spectral reflectance data 60 read as the initial value is selected from the existing glittering material data 62 of the glittering material-containing paint, the one having a glittering property close to the painted surface that the designer intends to develop is selected. Good.

  Subsequently, CAD data 64 describing the shape of the automobile body is read from the data storage unit 24 to the design development support apparatus 10 (S30).

  Subsequently, the angular distribution of the automobile body surface is calculated from the CAD data 64 (S40). The CPU 22 processes the CAD data 64 by the CAD program 70. The CAD program 70 draws the automobile body 300 described by the CAD data 64 in the XYZ space as shown in FIG. FIG. 14 shows only the door portion of the automobile body 300. In the following description, only the door portion will be described. By drawing the vehicle body 300 in the XYZ space using the CAD data 64, coordinate data describing the surface of the vehicle body in (xyz) coordinates can be obtained. Then, at each position on the surface of the automobile body 300 described by (xyz) coordinates, an angle (αβγ) formed by the normal line with the three orthogonal axes is obtained. In this way, the angle distribution data in which the coordinate data describing the position of the surface of the automobile body 300 and (αβγ) indicating the normal direction in the coordinates (xyz) are associated with each other is obtained.

  Subsequently, the position of the light source that illuminates the automobile body 300 and the position of the viewpoint that observes the automobile body 300 are designated (S50). The position of the light source may be specified by coordinates (x1, y1, z1) representing the position of the light source in the previous XYZ space. At this time, it is inconvenient to specify the coordinates (x1, y1, z1) directly because it is necessary to calculate the coordinates (x1, y1, z1) indicating the specified light source. Therefore, data describing the coordinates (x1, y1, z1) of the light source may be prepared in advance. For example, when the sun is used as the light source, the position of the sun is set at infinity, and the data describes only the sun direction. At this time, if it is data that takes into account calculations related to the orbit of the sun, the coordinates (x1, y1, z1) of the light source are set by designating, for example, “Sun on January 10 at 3 pm”. Regarding the position of the viewpoint to be observed, the position of the viewpoint may be specified by coordinates (x2, y2, z2) in the previous XYZ space. However, in this case as well, it is inconvenient because it is necessary to calculate the coordinates indicating the designated viewpoint position each time. Therefore, data describing the viewpoint position to be observed may be prepared in advance. For example, when a person standing at the same height as the car observes, by inputting the positional relationship between the height of the person to be observed and the car body 300, the coordinates of the position of the viewpoint to be observed (x2, y2, z2) can be set. The specification of the position of the light source and the viewpoint is performed using the keyboard 50 and the mouse 52. In this way, the light source position (x1, y1, z1) and the viewpoint position (x2, y2, z2) are set in the XYZ space shown in FIG.

  Subsequently, the CPU 22 uses the variable angle distribution calculation program 72 to calculate the distribution of the variable angle on the surface of the automobile body 300, and generates variable angle distribution data (S60). An example of calculation of the deflection at the position P (x, y, z) on the surface of the automobile body 300 shown in FIG. 14 will be described. The surface of the automobile body 300 is composed of a planar mesh, and the position P is a representative coordinate of each planar mesh. The incident direction from the designated light source position to the position P is obtained from the coordinates (x, y, z) of the position P and the coordinates (x1, y1, z1) of the light source position. Then, the regular reflection direction at the position P is obtained from the obtained incident direction and the normal direction of the position P described by the angle distribution data. On the other hand, the direction in which the position P is observed, that is, the direction from the position P to the viewpoint position is obtained from the coordinates (x, y, z) of the position P and the coordinates (x2, y2, z2) of the viewpoint position. When the regular reflection direction and the observation direction are obtained, the angle formed by the regular reflection direction and the observation direction is obtained as a variable angle. In this manner, the position (x, y, z) and the angle change at the position are calculated in all plane meshes on the surface of the automobile body 300, and the position (x, y, z) and the angle difference at the position are calculated. Deflection distribution data described in association is obtained.

  Subsequently, the CPU 22 uses the color distribution calculation program 74 to create color distribution data from the variable angle distribution data 34, the variable spectral reflectance data 60, and the glitter particle data 62 (S70). The color distribution calculation program 74 extracts the spectral reflectance corresponding to the variation in the position (x, y, z) of the surface of the automobile body 300 from the modified spectral reflectance data 60 and takes the glitter particle data 62 into account. To create color distribution data.

  Here, a procedure for creating color distribution data in which the irradiance spectral reflectance data 60 and the glitter particle data 62 are added will be described.

  The variable angle spectral reflectance data 60 of X, Y, and Z classified into three is calculated by multiplying the variable angle spectral reflectance data 60 by the light luminance ratio determined in the glitter particle property data 62. That is, the variable angle spectral reflectance of X is calculated by multiplying the variable angle spectral reflectance W at the position of each plane mesh on the surface of the automobile body 300 by the X light luminance ratio (c / A = 0.8), The variable angle spectral reflectivity W is multiplied by the Y light luminance ratio (d / A = 1.2) to calculate the variable angle spectral reflectivity of Y. The variable angle spectral reflectance of Z is calculated by multiplying the light intensity ratio of Z (e / A = 2.0).

  The results are shown in FIG. 15. For example, when the variable spectral reflectance of W is W1, the variable spectral reflectance of X is X1, the variable spectral reflectance of Y is Y1, and the variable spectral of Y is Z. The reflectance is calculated as Z1. Further, when the variable angle spectral reflectance of W is W2, the variable spectral reflectance of X is calculated as X2, the variable spectral reflectance of Y is Y2, and the variable spectral reflectance of Z is calculated as Z2.

  In FIG. 15, the light reception angle θ <b> 2 is 10 degrees at W <b> 1, which coincides with the light reception angle θ <b> 5 of the light luminance acquired by the light luminance measuring apparatus 200 (see FIG. 6). For this reason, there is no objection to applying the light luminance ratio based on the light luminance acquired by the light luminance measuring apparatus 200 to W1. On the other hand, at W2, the light receiving angle θ2 of the spectral reflectance is set to 25 degrees and does not coincide with 10 degrees of the light receiving angle θ5 of the light intensity. However, since it is considered that the dispersion of light luminance shows a similar shape at any light receiving angle, it is considered that the light luminance ratio based on the light luminance at one light receiving angle θ5 can be applied to each W at each light receiving angle θ2. . In this manner, the variable angle spectral reflectances of X, Y, and Z are calculated for each light receiving angle θ2 acquired every 30 to −60 degrees.

  Next, the planar mesh is divided into pixels, and each pixel is classified by light intensity level. For example, FIG. 17 enlarges the plane mesh 310 of the automobile body shown in FIG. 16, and the plane mesh 310 is shown divided into a plurality of pixels. By dividing each planar mesh into pixels, the entire painted surface is classified into pixels. Then, the divided pixels are classified for each light luminance level. With regard to the classification, for example, as illustrated in FIG. 12, for the pixels classified into the glitter material main part Y and the glitter material main part Z, random numbers obtained by randomly gathering the number of pixels according to the probability proportional to the pixel number ratio. It is expressed by a pattern (indicated by p) so that the realistic graininess of the glitter material can be displayed.

  Finally, the display paint color for each pixel is calculated. In this case, according to the light luminance level of each classified pixel, the already calculated variable spectral reflectance of the light luminance pixel is applied. That is, the X-angled spectral reflectance is applied to the pixels classified as the color material main portion X, and the Y-angled spectral reflectance is applied to the pixels classified as the bright material main portion Y. For the pixels classified into the material main part Z, the variable angle spectral reflectance of Z is applied. At this time, the paint color for CG display for each pixel is calculated by taking into account the deflection angle of the pixel in the object paint obtained from the object shape. For example, as shown in FIG. 18, when the deflection angle of one pixel included in the plane mesh 310 of the automobile body is θ31 and the pixel is classified as X, the pixel has the deflection angle θ31. When the variable angle spectral reflectivity of X is applied to the variable angle spectral reflectivity, and the variable angle of one pixel included in the planar mesh 312 is θ32 and the pixel is classified as Y, the pixel Applies the variable spectral reflectance of Y to the variable spectral reflectance of the variable angle θ32. In this way, the variable spectral reflectance is calculated for all the pixels on the entire painted surface, and the color distribution data describing the color of all the pixels on the entire painted surface with brightness, hue, and saturation is calculated.

  Returning to the description of the flowchart of FIG. 13, as shown in FIG. 19, the computer 20 processes the hue distribution data by the image display program 76 and displays the color distribution display 400 of the automobile body 300 on the display 40 ( S80). Corresponding to the variation in angle from the viewpoint depending on the position of the surface, the observed hue is also distributed. Further, the computer 20 processes the variable angle spectral reflectance data 60 by the image display program 76 and displays the graph display 410 to 440 of the variable angle spectral reflectance. Here, the graph display 410 is a graph display of L * values. The graph display 420 is a graph display of c * values. The graph display 430 is a graph display of a * values. The graph display 440 is a graph display of b * values. Note that the L * value, c * value, a * value, and b * value displayed in the graph here are calculated from the variable-angle spectral reflectance data 60 that is the base of the color distribution that does not take on the glitter. .

  Further, the computer 20 processes the variable angle spectral reflectance data 60 by the image display program 76, and displays a gradation display 450 indicating the change in color corresponding to the change in the change in the angle of the painted surface. Further, the glitter particle property parameter 460 used for calculating the color distribution data is displayed. Here, the displayed glitter particle parameter 460 is a light luminance ratio and a pixel number ratio included in the glitter particle data 62.

  That is, a color distribution display 400 on the surface of the object, a graph display 410 to 440 of the angle-change spectral reflectance of the painted surface that realizes the color distribution, a gradation display 450 that shows the color change corresponding to the change in angle change, The bright particle property parameter 460 is displayed so that it can be compared and observed. At this time, when a position is specified in the color distribution display 400, it is preferable that the portion displaying the variable angle at the specified position is highlighted in the graph display 410 to 440 or the gradation display 450. . For example, as shown in FIG. 19, when the position on the color distribution display 400 is designated, in the graphs 410 to 440, a straight line 470 is displayed at a position corresponding to the angle change at the position Q. Further, in the gradation display 450, the portion displaying the variable angle at the position Q is displayed with an arrow mark 480 or the like. Furthermore, the spectral reflectance with respect to the angle change at the designated position may be displayed numerically. As a result, the designer can accurately compare and observe the color displayed in the color distribution display 400 and the variable spectral reflectance of the color.

  When this contrast display is obtained, the designer can visually confirm the relationship between the color distribution display and the variable spectral reflectance. For example, when there is dissatisfaction with the color appearing in a specific variable angle area on the object surface, the spectral reflectance corresponding to the variable angle can be known.

  The designer determines whether or not it is necessary to change the brightness of the color distribution display displayed on the display 40 (S90).

  If the designer is not satisfied with the glitter, the glitter particle parameter 460 can be changed (S100). For example, when it is desired to enhance the “glare feeling”, the desired glitter is realized by changing the bright material main part Z to 8% and the bright material main part Y to 30%.

  In changing the glitter property, the designer may directly change the glitter particle parameter 460, or the glitter property and the glitter particle parameter 460 are associated with each other in advance, and the “glare feeling” as described above is obtained. The glitter particle property parameter 460 may be changed based on an instruction to increase the brightness.

  Using the changed glitter particle parameter 460, the color distribution data of the painted surface is created again in the same procedure as S70 (S110).

  The color distribution display 400 of the automobile body 300 displayed on the display 40 is changed by the recreated color distribution data (S120). In addition, the graph display 410 to 440 of the variable angle spectral reflectance displayed on the display 40 is changed. In addition, the gradation display 450 of the painted surface displayed on the display 40 is changed.

  Returning to S90, the designer observes the changed color distribution display 400 and determines whether or not it is necessary to change the glitter (S90).

  If it is not necessary to change the glitter in S90, it is determined whether or not the variable angle spectral reflectance data 60 that is the base of the color distribution needs to be corrected (S130).

  The designer can specify an area in which the color is dissatisfied in the color distribution display 400 displayed on the display 40, and can correct the spectral reflectance at the variable angle (S140).

  The designer designates a position for correcting the color in the displayed color distribution display 400. When the position is designated in the color distribution display 400, as shown in FIG. 19, in the graph displays 410 to 440, the portion displaying the variable spectral reflectance at the designated position is highlighted by a straight line 470. . As a result, the designer can know the angle change of the position where the color is corrected. The designer may correct the data associated with the angle change of the angle change spectral reflectance data 60. That is, the designer can easily change the color of an area where the color is unsatisfactory. For example, the L * value may be increased in order to increase the brightness of the color at the designated position. For example, the c * value may be increased in order to increase the saturation of the color at the designated position. For example, to add redness to the color, the a * value may be increased. At this time, it is easy to correct the spectral reflectance of the variable angle displayed in the graph on the display 40 directly in the form of correction on the graph display.

  Further, in the above correction, the designer may correct the spectral reflectance directly, or may cause the variable angle spectral reflectance calculation program 78 to calculate. For this purpose, the instruction content by the designer and the spectral reflectance correction calculation pattern may be taught in association with each other. For example, when the designer instructs to change the brightness, the variable spectral reflectance calculation program 78 changes the L * value. In such a correction form, the designer can correct the difference between the color distribution intended by the designer and the displayed color distribution in an expression based on sensitivity, for example, by inputting an instruction “brighter”. it can.

  The variable angle spectral reflectance data corrected by the designer is complementarily corrected by the variable angle spectral reflectance calculation program 78 (S150). An example of complementary correction when the designer corrects the L * value, for example, will be described with reference to FIG. In the color distribution display 400, the angle of change at the position specified by the designer is θ. Then, it is assumed that the L * value at the variable angle θ is corrected from L1 to L2. In the graph display 500 of FIG. 20, a curve (dotted line) 510 indicates L * value data corresponding to the inflection before correction. Since the L * value at the variable angle θ is corrected from L1 to L2, the relationship between the variable angle and the L * value is represented by a curve 520 instead of the curve 510. However, when the data is corrected only in the correction part of the designer, as shown by the curve 520, there is a range in which the rate of change rapidly changes in the relationship between the angle change and the L * value. It is difficult to obtain a painted surface that realizes such a relationship between the angle change and the L * value, even with a paint using any glittering material.

  Therefore, the variable spectral reflectance calculation program 78 complements and corrects the correction of data by the designer. This complementary correction is performed so that the change rate of the change rate of the L * value with respect to the angle change (that is, the curvature in the graph display 410) is equal to or less than a predetermined value. At this time, in the range of the variable angle smaller than the variable angle θ corrected by the designer, the correction is performed so that the corrected data range becomes the minimum range. Further, in the data range of the variable angle larger than the variable angle θ corrected by the designer, correction is performed so that the rate of change is the same as the data before correction. In this manner, the data describing the relationship between the angle change and the L * value in the angle difference spectral reflectance data 60 is complementarily corrected to the relationship indicated by the curve 530 in FIG.

  The corrected spectral reflectance data of the variable angle is updated to the variable spectral reflectance data 60 stored in the data storage unit 24 (S160).

  Using the updated variable-angle spectral reflectance data 60 and glitter particle data 62, color distribution data is created in the same manner as in S70. Then, the color distribution display 400 of the automobile body 300 displayed on the display 40 is changed by the updated color distribution data (S170). In addition, the graph display 410 to 440 of the variable angle spectral reflectance displayed on the display 40 is changed. In addition, the gradation display 450 of the painted surface displayed on the display 40 is changed.

  When the design development support device 10 according to the present invention is used in the process of determining the variable spectral reflectance of the painted surface for a car body by a designer, the change in which the desired glitter is added by correcting the glitter particle data is used. The color distribution display on the surface of the automobile body when the angular spectral reflectance is used is obtained.

  The determined variable spectral reflectance is a clear guide to paint designers, who can accurately understand the paint surface required by the designer, and the paint development process is streamlined and shortened. The

1 is a diagram illustrating a configuration of a design development support device 10. FIG. It is a figure explaining a variable angle. It is a figure which illustrates the measuring method of the variable angle spectral reflectance by the variable angle spectral reflectance measuring apparatus. It is a figure which illustrates the measuring method of the variable angle spectral reflectance by the variable angle spectral reflectance measuring apparatus. It is a figure which illustrates the measurement result of a variable angle spectral reflectance. It is a figure which illustrates the measuring method of the light luminance by the light luminance measuring apparatus 200. It is a figure which illustrates measurement image data of light intensity. It is a figure which illustrates measurement image data of light intensity. It is a figure which illustrates the histogram of light luminance dispersion. It is a figure which illustrates the histogram of light luminance dispersion. It is a figure explaining the classification | category of a light-luminance level. It is a figure explaining a pixel number ratio and a light-luminance ratio. 4 is a flowchart showing an operation procedure of the design development support apparatus 10. It is a figure explaining the data preparation regarding the vehicle body. It is a figure which illustrates the variable angle spectral reflectance for every light-luminance level. It is a figure which shows the plane mesh 310 on a motor vehicle body. 3 is an enlarged view of a planar mesh 310. FIG. It is a figure which shows the deflection angle for every surface mesh. It is a figure which shows the example of a screen display of the design development assistance apparatus. It is a figure explaining the complementary calculation of variable angle spectral reflectance data.

Explanation of symbols

  10 Design Development Support Device, 20 Computer, 22 CPU, 24 Data Storage Unit, 40 Display, 50 Keyboard, 52 Mouse, 60 Variable Angle Spectral Reflectance Data, 64 CAD Data, 70 CAD Program, 72 Variable Angle Distribution Calculation Program, 74 Color distribution calculation program, 76 image display program, 78 variable angle spectral reflectance calculation program, 80 glitter particle property correction program.

Claims (7)

A reflectance storage means for storing an initial value of the variable angle spectral reflectance of the painted surface;
Glitter particle data storage means for storing the initial value of the glitter particle data of the painted surface;
Angle distribution storage means for storing the angle distribution of the object surface;
Based on the assumed light source position, the assumed viewpoint position, and the angular distribution stored in the angular distribution storage means, the object illuminated by the light source is observed on the object surface at the viewpoint. A variable angle distribution calculating means for calculating the variable angle distribution;
Based on the variable angle distribution calculated by the variable angle distribution calculating means, the variable spectral reflectance stored in the reflectance storage means, and the glitter particle data stored in the glitter particle data storage means, Color distribution calculation means for calculating the color distribution of the object surface obtained when observing the object illuminated by a light source from the viewpoint;
Display means for displaying the color distribution calculated by the color distribution calculating means and the luminous particle property data used for the color distribution calculating means;
Correction means for correcting the glitter particle data,
Means for changing the color distribution display displayed on the display device to a color distribution calculated from the modified glitter particle data;
A design development support device characterized by comprising: The glitter particle property data includes a plurality of light brightness levels representing light brightness in a predetermined area, and a ratio of the number of unit areas of each light brightness level in the predetermined area,
The design development support apparatus according to claim 1, comprising:   The design development support apparatus according to claim 2, wherein the correction unit corrects the light luminance level or / and the ratio. The display means further displays a graph of variable angle spectral reflectance corresponding to the color distribution display,
Correction means for correcting the variable angle spectral reflectance displayed in a graph on the display device;
Means for updating the storage content of the reflectance storage means to the modified variable angle spectral reflectance;
Means for changing the color distribution display displayed on the display device to a color distribution calculated from the corrected spectral change reflectance and the initial or corrected glitter particle data;
The design development support apparatus according to claim 1, comprising: A process for assuming the variable spectral reflectance of the painted surface;
Assuming glitter particle data on the painted surface,
Calculating an angle distribution of the object surface obtained when observing the object illuminated by the light source from the viewpoint from the angle distribution of the object surface, the position of the light source, and the position of the viewpoint;
Calculating the color distribution of the object surface obtained when the object illuminated by the light source is observed from the viewpoint from the calculated variable angle distribution and the assumed variable angle spectral reflectance and glitter particle data;
Displaying the calculated color distribution on a display device ;
Correcting the glitter particle data; and
Changing the color distribution display displayed on the display device to a color distribution calculated from the modified glitter particle data;
A design development support method characterized by comprising: 6. The glitter particle property data includes a plurality of light luminance levels representing light luminance in a predetermined area and a ratio of the number of unit areas of each light luminance level in the predetermined area. The design development support method described.   The design development support method according to claim 6, wherein the step of correcting the glitter particle property data corrects the light brightness level or / and the ratio.

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