JP4616167B2 - Drawing method, image data generation system, CAD system, and viewer system - Google Patents

Description

  The present invention relates to a two-dimensional image output of a three-dimensional object, a method for drawing a contour line, a ridge line, and / or an interphase line for facilitating understanding of the three-dimensional shape, and an image using the drawing method. The present invention relates to a data generation system, a CAD system, and a viewer system.

  The present invention is particularly suitable for use in grasping the shape of a complex, high-density or large-scale arranged three-dimensional object generated by three-dimensional CAD (Computer Aided Design). The present invention relates to a method for drawing an interphase line.

  Conventionally, in the 2D image output of a 3D object, in order to make it easy to grasp the 3D shape, the hidden line that displays only the visible part from the viewpoint of the outline, ridgeline, and / or interphase line of the object is displayed. Line processing and hidden surface processing that displays only the visible part from the viewpoint of the shape surface of an object as an image are widely used.

  Here, the contour line means the boundary line between the visible surface and the invisible surface of the three-dimensional object, and the ridge line means the boundary line of the tangent discontinuity between the visible surface and the visible surface of the three-dimensional object, An interphase line means a boundary line where planes between different three-dimensional objects intersect.

  In the case of GWS (Graphics Work Station) and PC (Personal Computer) equipped with graphic functions, shading is used to display a state in which the color tone changes depending on the high-speed hidden surface processing and the light hitting state using the built-in hardware functions. By processing, it is widely performed to easily grasp the shape of a three-dimensional object.

These hidden surface processing and shading processing are specifically described in “Image Processing Handbook” (Shododo 1986) edited by the Image Processing Handbook Editorial Committee of Non-Patent Document 1.
Furthermore, by combining the line drawing of the above-mentioned hidden line processing and the image of the contour line and ridge line created using the distance information of the image in the hidden surface processing with the result of the shading process, an image with enhanced edges is generated. It has also been made easier to grasp the shape of a three-dimensional object.
This is described in Japanese Patent Laid-Open No. 3-123985 of Patent Document 1.

JP-A-3-123985 Image Processing Handbook Editorial Committee “Image Processing Handbook” (Shododo 1986)

  However, the method of making it easy to grasp the shape of a three-dimensional object using hidden line processing has a problem in that it requires time to calculate the contour line of the three-dimensional object and takes time. In the method using the hidden line processing, it is necessary to determine whether or not the contour line or the ridge line is obstructed from the viewpoint by another surface, and if necessary, it is necessary to divide the single contour line or the ridge line into a plurality of pieces. For this reason, processing time for the order of the square of the number of faces is basically required. For this reason, there is a problem that a very long calculation time is required particularly when drawing the shape of a three-dimensional object having a large number of surfaces.

  Also, the method using hidden line processing is easily affected by calculation errors when generating contour lines and dividing contour lines and ridge lines. There is also a problem that it is easy to happen.

  On the other hand, a method that makes it easy to grasp the shape of a three-dimensional object by combining hidden surface processing and shading processing is to speed up hidden surface processing and shading processing by using hardware functions built in GWS and PC. It can be carried out. However, in this method, since the user recognizes the change in color tone in the output of the two-dimensional image and grasps the shape of the three-dimensional object, particularly in the case of a three-dimensional object having many similar color surfaces. There is a problem that the outline is not clear and it is difficult or impossible to grasp the shape. In addition, printing on paper is usually performed by obtaining a hard copy of the screen of the output device. In particular, the entire shape of a complicated and large-scale high-density or large-scale arranged three-dimensional object is printed. In this case, there is a problem in that the resolution is insufficient with the number of screen pixels of the output device, and it is not possible to draw a fine part.

  Therefore, by combining the hidden surface processing and the shading processing, the interior of the surface is painted with the color of the surface of the object, and the boundary line of the surface is painted with, for example, black, thereby generating an image that emphasizes the edge of the three-dimensional object. It is also possible. However, in this method, for example, when one surface is divided into a plurality of surfaces for display such that a cylinder is divided into N prisms (N is an integer) for display, these are divided. There is a problem that the boundary of the surface is painted black. In addition, in the conventional method of generating an image in which an edge is enhanced by a combination of hidden surface processing and shading processing, the hidden line processing is used to generate the edge, and is described in the explanation of the hidden line processing described above. I have to consider the problem again.

  In addition, when an image of a contour line or a ridge line is generated using the image distance information in the hidden surface processing as described in Patent Document 1, the first-order differential in which the image distance information changes discontinuously. The image (the peak value of the first derivative) and the second derivative image (the peak value of the second derivative) in which the first derivative of the distance information of the image changes discontinuously are extracted, and the contour line is the first derivative image. And a ridge line is created based on this second-order differential image. Further, in the creation, correction is performed using a first-order differential maximum image or a first-order differential minimum image derived by first-order differentiation of an image (pixel) around the image (pixel) of interest, and correcting the problem. It is designed to create.

  However, when the image of the contour line or the ridge line is generated in this way by using the distance information of the image in the hidden surface processing, the peripheral image includes an image of the same or different surface as the image of interest. Therefore, there is a problem that an error is likely to occur. Moreover, although it is necessary to use an appropriate constant for the correction, there is a problem that it is difficult to determine an appropriate value because it depends on a target shape and a drawing purpose.

  Furthermore, since this method is mainly drawn by computer graphics, the edges are visually emphasized by changing the brightness of the image, so it is the same as the so-called hidden line processing that extracts only the contour lines and ridge lines. This image has a problem that it is difficult to generate the image.

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems and to easily understand the shape of a three-dimensional object, and to generate a contour line, a ridge line, and / or an interstitial line, and to generate image data using the drawing method. To provide a system and a viewer system.

In order to solve the above-described problems, the drawing method and the image data generation system of the present invention assign surface IDs (Identification) as different surface identification information to the respective surfaces of the three-dimensional object to be drawn, and then each of them. A hidden surface process is performed on the shape information of a three-dimensional object to which a different surface ID is assigned to generate image information of the three-dimensional object, and the surface ID of the pixel in the image information is used as a determination material. Image information representing a contour line, a ridge line, and / or an interphase line of a three-dimensional object is generated.

For this purpose, the drawing method of the present invention provides a contour line, a ridge line, and / or an interphase line that outputs a visible one of the contour line, ridge line, and / or interphase line of a three-dimensional object as a two-dimensional image. In this drawing method, a surface identification information adding step for assigning different surface identification information to each surface of a three-dimensional object to be drawn, and shape information of the three-dimensional object to which surface identification information is given by the surface identification information giving step A hidden surface processing step of generating image information of a three-dimensional object by performing hidden surface processing on the surface, and for identifying each pixel of the image information of the three-dimensional object generated in the hidden surface processing step, surface identification between adjacent pixels based on the difference information, contour, have a line drawing image generation step of generating image information representing a ridge line, and / or phase transmural lines, the line drawing image generation step, 3-dimensional generated in hidden surface processing step Next to each other image information of the object In the surface identification information for each of the four matching pixels, when the surface identification information of at least one of the pixels is different from the surface identification information of the remaining pixels, the contour line, the edge line, and / or the interphase line are represented. One pixel forming image information is generated so as to correspond to the center position of the four pixels .

In addition, the drawing method of the present invention provides a contour line, ridge line, and / or interphase line that outputs a visible image as a two-dimensional image out of the contour line, ridge line, and / or phase line of the three-dimensional object. A drawing method, a surface identification information adding step for assigning different surface identification information to each surface of a three-dimensional object to be drawn, and shape information of the three-dimensional object to which the surface identification information is given by the surface identification information adding step. A hidden surface process is performed to generate image information of a three-dimensional object, and distance information from the viewpoint of each pixel of the image information is prepared, and the 3D generated in the hidden surface process step For each pixel of the image information of the object, image information representing a contour line, a ridge line, and / or a continuous line is generated based on a difference in surface identification information between adjacent pixels and a difference in distance information from the viewpoint. Line drawing image generator Have a, the line drawing image generation step, contour, ridge, and / or a pixel that forms an image information representing a phase transmural lines, each other image information of a three-dimensional object generated by the hidden surface processing step It generates based on the difference with respect to the surface identification information regarding four adjacent pixels, and the comparison with respect to the reference value regarding the difference of the distance information from the viewpoint between two pixels in the four pixels .

  The image data generation system of the present invention is characterized in that image data is generated using the above-described drawing method for contour lines, ridge lines, and / or interphase lines.

  The CAD system and the viewer system of the present invention are characterized in that drawing image data is generated using the above-described drawing method of contour lines, ridge lines, and / or interphase lines.

  According to the present invention, a line drawing image of a contour line, a ridge line, and / or an interstitial line is generated by using a hidden surface erasure process and a difference in the surface ID of the pixel of the image. , Ridge lines, and / or two-dimensional images of three-dimensional objects having interpenetrating lines.

  Further, according to the present invention, it is possible to generate an image with necessary accuracy (number of pixels) by combining images generated by dividing into a plurality of images.

  In addition, according to the present invention, high-speed and high-precision contour lines, ridge lines, and / or interphase lines can be drawn using a PC or GWS that can display three-dimensional CAD data, and no special hardware is required. It can be realized at high speed with a simple system.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
As a first embodiment of the present invention, a drawing method for generating a black-and-white line drawing image of a three-dimensional object in which contour lines, ridge lines, and / or interphase lines are described will be described with reference to the drawings.

  FIG. 1 is a functional block diagram showing an example of a three-dimensional object image generation system employing the drawing method according to the first embodiment of the present invention.

  The image generation system includes a first data storage unit 11, a second data storage unit 12, a third data storage unit 13, an input / output unit 21, an ID assigning unit 31, a hidden surface processing unit 32, an image generation unit 33, A control means 41 is provided.

  The input / output unit 21 inputs and outputs data between an external device (not shown) and the first data storage unit 11, the second data storage unit 12, and the third data storage unit 13. The external device is, for example, an input device such as a CAD for creating and outputting shape information of a three-dimensional object, an information reading device for reading the shape information of a three-dimensional object, a display for displaying an image, and printing out an image. This corresponds to an output device such as a printer.

  The first data storage unit 11 includes shape information of a three-dimensional object supplied from an external device via the input / output unit 21 and display conditions set by the external device or the like (for example, position information of the viewpoint, light source) Information), etc.

  The second data storage unit 12 stores image information of the three-dimensional object that has been subjected to the hidden surface processing by the hidden surface processing unit 32 described later.

  The third data storage unit 13 stores two-dimensional output image information of a three-dimensional object for display / print output to an external device, and the like.

  The ID assigning unit 31 identifies each component surface (hereinafter simply referred to as a surface) of the three-dimensional object drawn by the shape information of the three-dimensional object stored in the first data storage unit 11. Different surface IDs are assigned as surface identification information. The ID assigning unit 31 assigns the surface ID using surface color information in the shape information of the three-dimensional object.

  Specifically, the shape information of the three-dimensional object includes surface color information for displaying an image of the shape of the three-dimensional object. The color information of the surface for image display represents each of R (red), G (green), and B (blue) color elements as data of 8 bits (that is, 256 levels), and 16.7 million colors. The color of the above surface can be expressed. Therefore, if surface color information in the shape information of the three-dimensional object is used as a surface ID, it is possible to identify more than 16.7 million surfaces of the three-dimensional object. The ID assigning means 31 assigns color information for identifying each surface in place of the original surface color information for displaying each image of the three-dimensional object in the shape information of the three-dimensional object. Thus, each surface of the three-dimensional object can be identified by the color information of the surface of the shape information of the three-dimensional object.

  The hidden surface processing means 32 is a surface different from the viewpoint among the surfaces forming the three-dimensional object based on the shape information of the three-dimensional object and the position information of the viewpoint stored as the display condition. Then, hidden surface removal processing is performed so as not to draw a surface portion that cannot be seen behind the object, and image information of the three-dimensional object is generated. Specifically, the hidden surface processing means 32 performs hidden surface processing on each pixel of the surface of the three-dimensional object drawn based on the shape information of the three-dimensional object, using a Z buffer method, a ray tracing method, or the like. The hidden surface processing performed by the hidden surface processing means 32 will be described by taking the Z buffer method as an example. Distance information (depth) from the viewpoint of each pixel of the surface of the three-dimensional object rendered based on the shape information of the three-dimensional object. Information), the depth information of pixels on different surfaces drawn on the same coordinates are compared, and the pixel information on the surface closest to the viewpoint is stored as image information of the three-dimensional object. It is like that. The image information of the three-dimensional object subjected to the hidden surface processing by the hidden surface processing means 32 is stored in the second data storage means 12.

Based on the image information of the hidden surface processed three-dimensional object stored in the second data storage unit 12, the image generation unit 33 uses the surface ID of each pixel in the image information to generate a contour line,
Image information representing a ridge line and / or an interphase line is generated as described later. The image generation unit 33 stores image information representing the generated contour line, ridge line, and / or phase line of the generated three-dimensional object in the third data storage unit 13.

The control means 41 controls each part of the image generation system such as the input / output means 21, the storage means 11 to 13, and information processing means such as the ID assigning means 31 and the hidden surface processing means 32.
FIG. 2 is a flowchart for explaining a flow of processing for generating a black and white line drawing image of a three-dimensional object in which an outline, a ridgeline, and / or an inset line are described by the three-dimensional object image generation system shown in FIG. It is.

  First, in step S101 of FIG. 2, the control unit 41 uses the input / output unit 21 shown in FIG. 1 to generate, for example, the shape information of the three-dimensional object generated by the CAD system of the external device, or the shape information of the three-dimensional object. When the display conditions set in displaying the image are received, they are stored in the first data storage means 11.

  Next, the control means 41 causes the ID provision means 31 to read the shape information of the three-dimensional object stored in the first data storage means 11 in step S102. The ID assigning means 31 assigns a surface ID composed of different color information for each surface, instead of the original color information of the surface for image display, to each surface rendered based on the shape information of the three-dimensional object. To do.

  In this case, the ID assigning means 31 gives the surface ID to each surface of the three-dimensional object represented by the shape information of the three-dimensional object with consistent serial number data from “1”, and each surface is relative to the other surface. It can be identified. For the consistent serial number data assignment, the color of each surface of the three-dimensional object is set to 8 bits (R (red), G (green), and B (blue) color elements) for image display. That is, the original color information of the surface expressed by 256 levels) is used. Therefore, the surface ID corresponds to the surface color information 1: 1. Accordingly, the ID assigning means 31 uses the color information different for each surface as the surface ID instead of the surface color information for displaying the original image of the shape information of the three-dimensional object, and as described above, consistently from “1”. The serial number data is mechanically assigned regardless of the original color of the surface.

  In addition, when the surface ID is assigned to each surface of the three-dimensional object as described above, one surface is divided into a plurality of surface regions in advance and approximated by a combination of the divided surface regions. The same surface ID is assigned to each of the divided surface regions divided into these regions. For example, when a cylinder is approximated by a polygonal cylinder, the peripheral surface of the cylinder is represented by a region divided by a plurality of outer peripheral flat surfaces of the polygonal column. The means 31 is configured to give the same surface ID to each of the plurality of outer peripheral flat surfaces of the polygonal column.

  Then, the shape information of the three-dimensional object to which the color information indicating the surface ID is assigned instead of the original surface color information by the ID assigning means 31 is stored in the first data storage means 11 by the control means 41. .

  Next, in step S103, the control means 41 is generated by the ID assigning means 31 and stored in the first data storage means 11, and the shape information of the three-dimensional object to which the color information indicating the surface ID is assigned. And the display condition thereof are read by the hidden surface processing means 32. Hidden surface processing (hidden surface erasure processing) is performed so as not to draw a surface that is not visible from the viewpoint or is hidden behind the object among the surfaces forming the three-dimensional object. By means 32. The image information of the three-dimensional object generated by the hidden surface processing unit 32 and subjected to the hidden surface processing and provided with color information indicating the surface ID for each pixel is stored in the second data storage unit 12.

  Next, in step S104, the control unit 41 converts the image information of the three-dimensional object to which the color information indicating the surface ID is assigned for each pixel stored in the second data storage unit 12 into the image generation unit. 33 is read. Then, the image generation means 33 generates image information (line drawing image information) representing the contour line, ridge line, and / or interphase line of the three-dimensional object using the color information indicating the surface ID of the image information. Image information representing the contour line, ridge line, and / or phase line of the three-dimensional object generated by the image generation unit 33 is stored in the third data storage unit 13 as two-dimensional output image information of the three-dimensional object. The

  Here, the details of the generation processing of the image information representing the contour line, the ridge line, and / or the interphase line of the three-dimensional object by the image generation unit 33 shown in step S104 will be described with reference to FIG. In the description, the image information of the three-dimensional object to which the color information indicating the surface ID is assigned for each pixel generated by the hidden surface processing unit 32 in step S103 described above is given. The number of pixels is described as m × n (number).

  FIG. 3 is a PAD (Problem Analysis Diagram) illustrating details of processing for generating image information representing the contour line, edge line, and / or phase line of a three-dimensional object by the image generation means.

  First, in steps S111 and S112, the image generating means 33 uses variables i, i, which specify the pixel P (i, j) in the image information of the three-dimensional object to which color information indicating the surface ID is assigned for each pixel. j is changed in each of the pixel number ranges 1 to m and 1 to n of the image information, and in step S113, all the images displayed with the image information of the three-dimensional object to which the color information indicating the surface ID is assigned Color information indicating the surface ID of the pixel P is captured.

  In parallel with the capturing of the color information indicating the surface IDs of all the pixels P (i, j), the image generating means 33 performs pixel processing for each of the captured pixels P (i, j) in steps S114 and S115. Variables i and j that specify P (i, j) are sequentially changed in the range of 1 to m−1 and 1 to n−1, and are set as determination targets for contour lines, ridge lines, and / or interphase lines. While sequentially changing the target pixel P (i, j), in step S116, for each target pixel P (i, j), four adjacent pixels including the target pixel P (i, j), for example, P (i , j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) are compared with the color information indicating the surface ID.

In addition, the image generation means 33 may use any one of the four pixels P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) adjacent to each other as color information. Are different, in step S117, the image portion of the three-dimensional object represented by the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1). Is determined to have a contour line, a ridge line, and / or an interpenet line, and one of the contour line, the ridge line, and / or the interpenet line is formed corresponding to the target pixel P (i, j). A new pixel Q (i, j) is generated. Specifically, the image generation means 33 corresponds to the target pixel P (i, j), for example, a black color as color information indicating that a contour line, a ridge line, and / or a continuous line is formed. A pixel Q (i, j) that represents the contour line, the edge line, and / or the interphase line to which the information is added is generated.

  On the other hand, the image generating means 33 has the same color information for all four adjacent pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1). If there is, in step S118, the image portion of the three-dimensional object represented by the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1) is added. Determines that there is no contour line, ridge line, and / or interphase line, and newly generates one pixel Q (i, j) for forming a surface corresponding to the target pixel P (i, j) To do. Specifically, the image generation unit 33 associates the target pixel P (i, j) with, for example, a pixel Q representing a surface to which white color information is added as color information indicating that the surface is formed. (i, j) is generated.

  In step S119, the image generation unit 33 stores and accumulates the newly generated pixel Q (i, j) in the third data storage unit 13. Therefore, the image generation means 33 converts all the pixels P (1,1) to P (m−1, n−1) to new pixels Q (1,1) to Q (m−1, n−1). The converted image information of the three-dimensional object is stored in the third data storage unit 13 as image information representing the contour line, the ridge line, and / or the intermittence line of the three-dimensional object.

  Here, the pixels P (1, 1) to P (3) of the image information of the three-dimensional object to which the color information indicating the surface ID generated by the hidden surface processing means 32 is given for each pixel. m, n) and pixels Q (1,1) to Q (m-1, n) of the image information representing the contour line, ridge line, and / or phase line of the three-dimensional object generated by the image generation means 33 -1) will be described with reference to FIGS. 4 and 5. FIG.

  FIG. 4 is an explanatory diagram of the correspondence between the pixels generated by the image generation unit and the pixels generated by the hidden surface processing unit.

  In FIG. 4, pixels P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) are contours when the pixel P (i, j) is the target pixel. It is the example which illustrated four pixels adjacent to each other as a determination target for a line, a ridge line, and / or an interphase line. Note that the mutual arrangement of P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) in FIG. 4 is convenient, and an image of a three-dimensional object. It varies depending on the pixel arrangement of information.

  In this case, the image generation means 33 performs the above-described processing of steps S114 to S118, and the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1) ) A pixel Q (i, j) corresponding to the target pixel P (i, j) is newly generated using the color information indicating each surface ID.

  At that time, the image generating means 33 newly generates a pixel Q (i, j) corresponding to the target pixel P (i, j) as a comparison target of the pixel Q (i, j). The four pixels P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) are generated so as to correspond to the center position.

  Here, the generated pixel Q (i, j) and the comparison original pixel 4 pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1) and The arrangement relationship on the image will be described in detail.

  In the description, the coordinate value of the pixel P (i, j) on the image is represented by [X (i, j), Y (i, j)], which is represented by the center position of the pixel, and X on the image. , Y and Y direction pixel image pitches are Δx and Δy, respectively.

In such a case, P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) among the four pixels that are the basis of comparison are as follows.
P (i, j + 1) = [X (i, j + 1), Y (i, j + 1)]
= [X (i, j) + Δx, Y (i, j)]
P (i + 1, j) = [X (i + 1, j), Y (i + 1, j)]
= [X (i, j), Y (i, j) + Δy]
P (i + 1, j + 1) = [X (i + 1, j + 1), Y (i + 1, j + 1)]
= [X (i, j) + Δx, Y (i, j) + Δy]

  Here, the coordinate values of the pixel Q (i, j) are the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1) that are the basis of comparison. ) Is an average value of coordinate values by each, and such an arrangement position is expressed by “4 pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1)”. It is called “the center position of”.

Thus, the coordinate value of the pixel Q (i, j) is
Q (i, j) = (P (i, j) + P (i, j + 1) + P (i + 1, j) + P (i + 1, j + 1)) / 4
= (X (i, j) + Δx / 2, Y (i, j) + Δy / 2)
Thus, the positional relationship is such that the surrounding four pixels are evaluated equally.

  In this case, the resolution (pixel pitch) of the generated image is the same as the resolution (pixel pitch) of the comparison image.

  Therefore, when the number of pixels of the image information of the three-dimensional object subjected to the hidden surface processing by the hidden surface processing means 32 is m × n (pieces), the contour line, the ridge line of the three-dimensional object generated by the image generating means 33, And / or the number of pixels of the image information representing the intermittence line is (m−1) × (n−1) (number), and before and after the generation of the contour line, the ridgeline, and / or the intermittence line, Each image area has a different size.

  Therefore, the surface ID of the three-dimensional object generated by performing the hidden surface processing by the hidden surface processing means 32 on the image region of the image representing the contour line, the ridge line, and / or the interphase line of the three-dimensional object to be generated. It is necessary to widen the image area of the image to which the color information shown is given. Therefore, in the present embodiment, for example, the horizontal and vertical pixel numbers of the image representing the contour line, ridge line, and / or interphase line of the three-dimensional object to be generated are designated by m × n (pieces) and display conditions. The number of horizontal and vertical pixels of the image to which the color information indicating the surface ID of the three-dimensional object generated by performing the hidden surface processing is added is increased by one pixel (m + 1) × The control means 41 is configured to automatically expand the image area to be subjected to the hidden surface processing by controlling the ID assigning means 31 and the hidden surface processing means 32 so as to be (n + 1) (pieces). ing.

  FIG. 5 shows image information representing contour lines, ridge lines, and / or interphase lines of a three-dimensional object by the three-dimensional object image generation system employing the drawing method according to the present embodiment described in FIGS. It is the figure which showed the example of a production | generation.

  FIG. 5A shows image information 201 of a three-dimensional object that has been subjected to hidden surface processing by the hidden surface processing means 32.

In the figure, a rectangular portion in which a numeric number is entered represents an individual pixel P of the image information 201 that has been subjected to the hidden surface processing by the hidden surface processing means 32 of the three-dimensional object, and the numerical number of the individual pixel P is This corresponds to the color information indicating the surface ID.

  In FIG. 5A, the image information 201 subjected to the hidden surface processing of the three-dimensional object includes a surface 202 in which color information indicating the surface ID appears in a reverse “U” shape of “1”. A rectangular surface 203 in which color information indicating an ID appears to be fitted into a concave portion of a “U” -shaped surface 202 of “2”, and a protrusion of the rectangular surface 203 from the concave portion The color information indicating the surface IDs arranged so as to sandwich the side portion is represented by a surface configuration including rectangular surfaces 204 and 205 of “3” and “4”, respectively.

  FIG. 5B shows color information (1, 2, 2) indicating the surface ID of each pixel P of the image information 201 subjected to the hidden surface processing of the three-dimensional object shown in FIG. ...) represents a state when the corresponding individual pixel Q for generating the contour line, the ridge line, and / or the interphase line is generated.

  In FIG. 5B, all the color information indicating the surface IDs of the four pixels P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) adjacent to each other. Similarly, a pixel Q (i, j) whose color information is white color information representing a surface is indicated by a white circle symbol, and four adjacent pixels P (i, j) and P (i, j + 1). ), P (i + 1, j), and P (i + 1, j + 1) are not all the same color information indicating the surface ID, and the color information is black color information indicating a contour line, a ridgeline, and / or an intermittence line. Each pixel Q (i, j) is represented by a black circle symbol.

  FIG. 5C shows image information representing contour lines, ridge lines, and / or interphase lines of a three-dimensional object stored and stored as two-dimensional output image information in the third data storage means.

  FIG. 5C shows the respective pixels Q described with reference to FIG. 5B, and a contour line, a ridge line, and / or a boundary portion between the surfaces 202 to 205 shown in FIG. The two-dimensional output image information 206 is generated in which a pixel Q having black color information for representing a continuous line is generated and a pixel Q having white color information for representing a surface is generated in the other part. Represents.

  According to the contour line, ridge line, and / or interphase line drawing method of the present embodiment described above, hidden surface erasure processing is performed using the color information from the shape information of the three-dimensional object as the surface ID. Based on the difference in color information indicating the surface ID for each pixel in the image information of the three-dimensional object, a black-and-white line drawing image of the three-dimensional object in which the contour line, the ridge line, and / or the interphase line is described is easily acquired. be able to.

  In addition, in this embodiment, the color information of the surface of the shape information of the three-dimensional object is replaced with the color information of the original surface, and different color information for each surface is assigned as the surface ID. Therefore, by using the hardware for image processing of GWS and PC, no special hardware is required, and the surface ID of each pixel can be obtained by only obtaining the color information of each pixel of the image information subjected to the hidden surface processing. Can be collected.

  Furthermore, image information representing contour lines, ridge lines, and / or interphase lines can be easily generated by simply determining the difference in color information between adjacent pixels for each pixel of image information subjected to hidden surface processing. Since it can be generated, it can be realized at high speed with a simple system.

[Second Embodiment]
As a second embodiment of the present invention, a drawing method for generating a monochrome line drawing image in which a contour line, a ridge line, and / or an interphase line of a three-dimensional object are described will be described based on the drawings.

The contour line, ridge line, and / or phase line drawing method according to the present embodiment overlaps so that a part of the surface is hidden due to a torus surface or a free-form surface. Even a three-dimensional object having a portion that can be seen from the viewpoint can acquire a monochrome line drawing image in which a contour line and a ridge line are written in the overlapped portion.

  The three-dimensional object image generation system employing the contour line, ridge line, and / or phase line drawing method according to the present embodiment is a three-dimensional image employing the drawing method according to the first embodiment shown in FIG. The object image generation system is the same except that the internal configuration of the hidden surface processing means 32 and the image generation means 33 is different. Therefore, the description of the system configuration will be omitted, and the same components will be described using the same names and symbols shown in FIG.

  FIG. 6 shows a method of generating a monochrome line drawing image of a three-dimensional object in which contour lines, ridge lines, and / or interphase lines are described by the three-dimensional object image generation system employing the drawing method according to the present embodiment. It is a flowchart explaining the flow of processing.

  First, in step S121 of FIG. 6, when the control means 41 receives the supply of the shape information and display conditions of the three-dimensional object from the external device by the input / output means 21, in the same manner as in step S101 shown in FIG. And stored in the first data storage means 11.

  Next, in step S122, the control means 41 reads the shape information of the three-dimensional object from the first data storage means 11 into the ID assigning means 31 in the same manner as in step S102 shown in FIG. Instead of the color information for displaying the original image on each surface, color information indicating the surface ID is added to the shape information. The control unit 41 causes the first data storage unit 11 to store the shape information of the three-dimensional object to which the color information indicating each surface ID is added by the ID providing unit 31.

  Next, in step S123, the control means 41 displays the shape information and display of the three-dimensional object to which the color information indicating the surface ID is given from the first data storage means 11 in the same manner as in step S103 shown in FIG. The condition is read by the hidden surface processing means 32 to perform the hidden surface processing. The control unit 41 performs hidden surface processing by the hidden surface processing unit 32 on the shape information of the three-dimensional object to which the color information indicating the surface ID is given, and the generated image information of the three-dimensional object is stored in the second data storage unit 12. To remember. In the case of the present embodiment, the image information of the three-dimensional object stored in the second data storage unit 12 includes, for each pixel of the surface used when the hidden surface processing unit 32 performs the hidden surface processing. Information about depth from the viewpoint (depth information) is also included.

  Next, in step S124, the control means 41 performs the hidden surface processing by the hidden surface processing means 32 and stores the three-dimensional object stored in the second data storage means 12 in the same manner as in step S104 shown in FIG. The image generation unit 33 reads the image information, and the image generation unit 33 uses the color information indicating the surface ID of the image information and the depth information for each pixel of the surface, Image information representing a ridge line and / or an interphase line is generated. Then, the image information representing the contour line, ridge line, and / or interphase line generated by the image generation unit 33 is stored in the third data storage unit 13 as the two-dimensional output image information of the three-dimensional object. Is done.

  Details of the process of generating image information representing the contour line, ridge line, and / or phase line of the three-dimensional object by the image generation means 33 shown in step S124 will be described with reference to FIG. In the description, in step S123 described above, the color information indicating the surface ID, which is generated by performing the hidden surface processing by the hidden surface processing unit 32, is added, and depth information for each pixel of the surface is added. The number of pixels of the image information of the three-dimensional object is described as m × n (pieces).

  FIG. 7 is a PAD showing details of a process of generating image information representing the contour line, ridge line, and / or interphase line of the three-dimensional object by the image generation means described in FIG.

Note that the processing by the image generation means 33 in steps S131 to S135 shown in FIG.
Is substantially the same as the processing by the image generation means 33 in steps S111 to S115 already described. The difference is that the image information of the three-dimensional object generated by performing the hidden surface processing by the hidden surface processing means 32 from the second data storage means 12 shown in step S133 corresponding to step S113 in FIG. In addition to the color information indicating the surface IDs of all the pixels P of the image information of the three-dimensional object, the only difference is that the depth information of all of the pixels P is acquired, and the others are the same.

  Here, from the pixel P (i, j) of the image information of the three-dimensional object captured from the second data storage means 12 after step S136 shown in FIG. A process for generating the pixel Q (i, j) of the image information representing the interphase line will be described in detail.

  In parallel with the capture of color information and depth information indicating the surface IDs of all the pixels P (i, j) in the image information of the three-dimensional object shown in steps S131 to S133, the image generation means 33 performs steps While sequentially changing the target pixel P (i, j) that is the target of the presence determination of the contour line, the ridge line, and / or the interphase line in S134 and S135, in step S136, for each target pixel P (i, j) Each of four adjacent pixels including the target pixel P (i, j), for example, P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) The color information indicating the ID is compared.

  In addition, the image generation means 33 may use any one of the four pixels P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1) adjacent to each other as color information. Are different, in step S137, the image portion of the three-dimensional object represented by the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1). Is determined to have a contour line, a ridge line, and / or an interpenet line, and one pixel Q (i representing the contour line, the ridge line, and / or the interpenet line corresponding to the target pixel P (i, j). , j) is newly generated. Specifically, the image generation means 33 corresponds to the target pixel P (i, j), for example, a black color as color information indicating that a contour line, a ridge line, and / or a continuous line is formed. A pixel Q (i, j) that represents the contour line, the edge line, and / or the interphase line to which the information is added is generated.

  On the other hand, the image generating means 33 has the same color information for all four adjacent pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1). If there is, in step S138, two adjacent pixels among the four adjacent pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1) The maximum depth information difference is compared with a preset reference value. This reference value is set based on a step in the depth on the same plane caused by a torus surface, a free-form surface, or the like.

  Then, the image generation means 33 calculates the depth of two adjacent pixels among the four adjacent pixels P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1). If the maximum value of the information difference is greater than or equal to the reference value, in step S139, the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1, j + 1) It is determined that there is a contour line and a ridge line in the image portion of the three-dimensional object represented by (1), and one pixel Q (i, j) representing the contour line and the ridge line corresponding to the target pixel P (i, j) is obtained. Create a new one. Specifically, in this embodiment, the image generation unit 33 also forms, for example, a contour line, a ridge line, and / or an intermeshing line corresponding to the target pixel P (i, j) in this embodiment. A pixel Q (i, j) representing a contour line, a ridge line, and / or an interstitial line, to which black color information is added as color information indicating this, is generated.

  On the other hand, the image generation means 33 has two adjacent pixels among the four adjacent pixels P (i, j), P (i, j + 1), P (i + 1, j), and P (i + 1, j + 1). If the maximum difference in pixel depth information is smaller than the reference value, the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i + 1) are determined in step S140. , j + 1) is determined to have no contour line, ridge line, and / or interstitial line in the image portion of the three-dimensional object represented by one, and represents one surface corresponding to the target pixel P (i, j). A new pixel Q (i, j) is generated. Specifically, the image generation unit 33 associates the target pixel P (i, j) with, for example, a pixel Q representing a surface to which white color information is added as color information indicating that the surface is formed. (i, j) is generated.

  As described above, the case where the image generation unit 33 newly generates the pixel Q (i, j) corresponding to the target pixel P (i, j) is also described in the first embodiment. As described above, in any case, the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (from which the pixel Q (i, j) is compared are based. It is generated so as to correspond to the center position of i + 1, j + 1).

  In step S140, the image generation unit 33 stores and accumulates the newly generated pixel Q (i, j) in the third data storage unit 13 in the same manner as in step S119 already described with reference to FIG. . Therefore, the image generation means 33 converts all the pixels P (1,1) to P (m−1, n−1) to new pixels Q (1,1) to Q (m−1, n−1). The converted image information of the three-dimensional object is stored in the third data storage unit 13 as image information representing the contour line, the ridge line, and / or the intermittence line of the three-dimensional object.

  At this time, as described above, for all the pixels Q (i, j), the four pixels P (i, j), P (i, j + 1), P (i + 1, j), P (i, j), Since the pixel is generated so as to correspond to the center position of P (i + 1, j + 1), even when the pixels representing the lines generated in steps S137 and S139 are combined, a new special visual effect is generated by the combination. It is possible to generate an accurate drawing image of a three-dimensional object without doing so.

  As described above, according to the drawing method for generating the monochrome line drawing image of the contour line, the ridge line, and / or the interphase line according to the present embodiment described above, the surface of the surface caused by the torus surface, the free-form surface, or the like is generated. Even for a three-dimensional object having a portion that is partially overlapped so as to hide other portions of the same surface and visible from the viewpoint, a black and white image in which a contour line and a ridge line are written in the overlapped portion can be acquired.

  In the present embodiment, the image generating unit 33 superimposes a part of the surface so as to hide the other part of the same surface in the process of step S139, and expresses the pixel Q that represents the contour line and the edge line of the part that can be seen from the viewpoint. The color information of the pixel Q is set to the same black color as the color information of the pixel Q representing the other contour line, ridge line, and / or interphase line of the three-dimensional object in the process of step S137, but the color information of the two is different. Thus, it is possible to distinguish whether or not the surfaces on both sides of the line are the same by the density of the contour line and the edge line in the monochrome line drawing image.

[Third Embodiment]
Next, as a third embodiment of the present invention, a drawing method for generating a color image in which a contour line, a ridge line, and / or an interphase line of a three-dimensional object are emphasized will be described with reference to the drawings.

  The three-dimensional object image generation system employing the contour line, ridge line, and / or phase line drawing method according to the present embodiment is a three-dimensional image employing the drawing method according to the first embodiment shown in FIG. The object image generation system and the hidden surface processing unit 32 perform shading processing in addition to the hidden surface processing, and the third data storage unit 13 stores another image information (one image information ( This is the same except that the image superimposing means 34 for overwriting the image information representing the contour line, the ridge line, and / or the interphase line is further connected. Therefore, detailed description of the system configuration is omitted, and the same components will be described using the same names and symbols shown in FIG.

  FIG. 8 shows the processing of the method of generating a color image of a three-dimensional object with an emphasized outline, ridgeline, and / or interphase line by the three-dimensional object image generation system employing the drawing method according to the present embodiment. It is the flowchart explaining the flow.

  First, in step S151, the control means 41 stores the first data storage means 11 when the input / output means 21 receives the shape information and display conditions of the three-dimensional object from the external device.

  Next, in step S152, the control unit 41 causes the hidden surface processing unit 32 to read the shape information to which the color information of the original surface of the three-dimensional object is added from the first data storage unit 11 and the display conditions. The hidden surface processing means 32 performs hidden surface processing and shading processing. The control means 41 converts the image information reflecting the original surface color information of the three-dimensional object obtained by the hidden surface processing and the shading processing by the hidden surface processing means 32 into contour lines, ridge lines, and / or interphase lines. Is stored in the second data storage unit 12 as two-dimensional color image information that serves as a base image of a color image of a three-dimensional object. That is, the color information of each pixel of the two-dimensional color image information is the color information of the original color of the surface portion of the three-dimensional object represented by the pixel.

  Next, in step S153, the control unit 41 reads the shape information of the three-dimensional object from the first data storage unit 11 into the ID assigning unit 31, and causes each surface of the three-dimensional object to have a surface as a different surface ID. Color information is assigned.

In this case, as described in step S102 of FIG. 2 in the first embodiment, the ID assigning unit 31 replaces the original color information of each surface drawn based on the shape information of the three-dimensional object, for example, A consistent serial number from “1” is given, and a surface ID composed of different color information is assigned to each surface to be drawn based on the shape information of the three-dimensional object so that each surface can be identified. . Therefore, in the shape information of the three-dimensional object to which the color information indicating the surface ID is assigned instead of the color information of the original surface generated by the ID assigning means 31, the color information of the surface is the color of the original surface. It is not a representation but a convenience for representing the identification of the surface. The control means 41 stores in the first data storage means 11 the shape information of the three-dimensional object to which the color information indicating the surface ID obtained by the ID assignment means 31 is assigned.

  Next, in step S154, the control means 41 is the same as step S103 shown in FIG. 2, and the three-dimensional object to which the color information indicating the surface ID is assigned from the first data storage means 11 by the ID assigning means 31. The shape information and the display conditions are read into the hidden surface processing means 32 to perform the hidden surface processing. The hidden surface processing means 32 performs color information indicating the surface ID instead of the original surface color information in the same manner as the generation of the image information reflecting the original surface color information of the three-dimensional object. The hidden surface process and the shading process are also performed on the shape information of the three-dimensional object to which image information is assigned, and image information of the three-dimensional object to which color information indicating the face ID is assigned for each pixel is generated. The control means 41 uses the second data storage means as the image information for surface identification that becomes the base image of the image information of the three-dimensional object to which the color information indicating the surface ID generated by the hidden surface processing means 32 is given. 12 to store.

  Therefore, the second data storage unit 12 stores the image information of the three-dimensional object reflecting the original color information of the three-dimensional object as the above-described two-dimensional color image information and the surface ID for surface identification. The image information of the three-dimensional object to which the color information shown is given is stored.

Next, in step S155, the control unit 41 causes the image generation unit 33 to read the image information of the three-dimensional object to which the color information indicating the surface ID for surface identification is added. Image information representing a contour line, a ridge line, and / or an interphase line of a three-dimensional object is generated. As a method for generating image information representing the contour line, ridge line, and / or interphase line of the three-dimensional object by the image generating means 33, the method of step S104 shown in FIG. 2 or step S124 shown in FIG. 6 is used. In this case, in the details of the generation process shown in FIG . 3 or FIG. 7 , in step S117 of FIG. 3 or step S139 of FIG. , j) is generated, a pixel Q (i, j) to which black color information is added as color information is generated, whereas a pixel representing a surface in step S118 of FIG. 3 or step S140 of FIG. When Q (i, j) is generated, no color information is given, and the color is not colored.

  Image information representing the contour line, ridge line, and / or interphase line of the three-dimensional object generated by the image generation unit 33 is stored in the third data storage unit 13 as line drawing image information.

  Next, in step S156, the control means 41 is a two-dimensional color image which is image information of the three-dimensional object reflecting the original surface color information of the three-dimensional object stored in the second data storage means 12. Information and line drawing image information which is image information representing the contour line, ridge line, and / or interphase line of the three-dimensional object generated by the image generation unit 33 stored in the third data storage unit 13 The image data is read by the superimposing unit 34 and the both image information is superimposed.

  The image superimposing means 34 reads both pieces of image information, overwrites the two-dimensional color image information of the three-dimensional object with the line drawing image information representing the contour line, ridge line, and / or interphase line of the three-dimensional object, and finally Two-dimensional color output image information is generated. The generated two-dimensional color output image information is stored in the third data storage unit 13.

  As a result, the output image based on the two-dimensional color output image information stored in the third data storage unit 13 has an edge of the two-dimensional color image that has been subjected to the hidden surface processing / shading processing of the three-dimensional object. The image is further emphasized by the entry of the intermittence line, and it becomes easier to grasp the three-dimensional object.

  FIG. 9 shows an example of generating two-dimensional color output image information in which a contour line, a ridge line, and / or an interphase line of a three-dimensional object are emphasized by a three-dimensional object image generation system employing the drawing method according to the present embodiment. FIG.

  The image information 211 is generated by performing hidden surface processing and shading processing by the hidden surface processing means 32 on the shape information to which the color information of the original surface of the three-dimensional object is added. This is two-dimensional color image information that is image information of a three-dimensional object in which color information is reflected. In the figure, a rectangular portion in which a numeric number is entered represents an individual pixel P in the two-dimensional color image information 211 of the three-dimensional object, and the numeric number corresponds to the color information of the original surface of the three-dimensional object. Is.

  In the illustrated case, the two-dimensional color image information 211 of the three-dimensional object includes a surface 212 appearing in a reverse “U” shape whose surface ID (color information) is “5”, and a surface ID (color information). The rectangular surface 213 that appears by fitting into the concave portion of the “6” “U” -shaped surface 212 and the protruding side portion of the rectangular surface 203 from the concave portion are arranged to be sandwiched therebetween. A surface configuration is formed of rectangular surfaces 214 and 215 having surface IDs (color information) of “8” and “9”, respectively.

  On the other hand, the image information 216 is obtained by the hidden surface processing unit 32 from the shape information of the three-dimensional object to which the color information indicating the surface ID is added instead of the original surface color information generated by the ID providing unit 31. This is image information representing a contour line, a ridge line, and / or an interphase line of a three-dimensional object generated by performing processing and shading processing. In the drawing, a rectangular portion with a black circle symbol indicates an individual pixel Q corresponding to an individual pixel P that forms a contour line, a ridge line, and / or an interstitial line. On the other hand, a rectangular portion with a white circle symbol indicates an individual pixel Q corresponding to the individual pixel P forming the surface.

  The image information 217 is added to the two-dimensional color image information 211, which is the image information of the three-dimensional object in which the color information of the original surface of the three-dimensional object is reflected, by the image superimposing unit 34. And / or image information (two-dimensional color output image information) of a color image of a three-dimensional object generated by overwriting the line drawing image information 216 representing the interpenet line and emphasizing the contour line, the ridge line, and / or the interpenet line. ).

  Therefore, according to the drawing method of the present embodiment, it is possible to acquire a color image in which the contour line, ridge line, and / or interphase line of a three-dimensional object are emphasized.

[Fourth Embodiment]
Next, as a fourth embodiment of the present invention, a drawing method for enhancing a contour line, a ridge line, and / or an interstitial line of a three-dimensional object and generating a color image including a translucent display will be described. Based on

The three-dimensional object image generation system employing the contour line, ridge line, and / or phase line drawing method according to the present embodiment is a three-dimensional image employing the drawing method according to the first embodiment shown in FIG. The object image generation system and the hidden surface processing unit 32 perform shading processing in addition to the hidden surface processing, and the first data storage unit 11 and the third data storage unit 13 include the hidden surface processing. A semi-transparent image generating means 37 for generating a semi-transparent image by performing blending processing of the image color is connected, and the third data storage means 13 is provided with an image superimposing means 34 connected thereto. The configuration is the same.

  Therefore, the detailed description of the system configuration is also omitted in this embodiment, and the same components will be described using the same names and symbols shown in FIG.

  FIG. 10 is a flowchart illustrating a processing flow of a method for generating an image of a contour line, a ridge line, and / or an interpenetration line by the three-dimensional object image generation system employing the drawing method according to the present embodiment. .

  First, in step S161, the control unit 41 uses the input / output unit 21 to specify the color of the original surface of the three-dimensional object in which the three-dimensional shape of the three-dimensional object that is displayed semi-transparently and the three-dimensional shape that is not displayed semi-transparently are indicated. When the supply of the three-dimensional shape information to which the information is given and the display conditions are received, these are stored in the first data storage means 11.

  Next, in step S162, the control means 41 obtains the shape information to which the color information of the original surface of the three-dimensional shape that is not translucently displayed of the three-dimensional object from the first data storage means 11 and the display conditions. The hidden surface processing means 32 is read. The hidden surface processing means 32 performs hidden surface processing and shading processing on the shape information to which the color information of the original surface of the three-dimensional shape that is not semi-transparently displayed of the three-dimensional object is applied, and does not display the semi-transparent of the three-dimensional object. Two-dimensional color image information about a three-dimensional shape is generated. The control unit 41 stores the two-dimensional color image information of the three-dimensional shape that is not translucently displayed by the hidden surface processing unit 32 in the second data storage unit 12 as the image information 1.

  That is, the color information of each pixel in the three-dimensional shape two-dimensional color image information (image information 1) of the three-dimensional object that is not translucently displayed is the three-dimensional surface of the three-dimensional object that the pixel represents that is not translucently displayed. The color information indicates the original color of the part.

  Next, in step S163, the control unit 41 obtains shape information and display conditions to which the color information of the original surface of the three-dimensional shape that is not translucently displayed of the three-dimensional object is added from the first data storage unit 11. The ID assigning unit 31 reads the information and assigns color information of a surface as a different surface ID to each surface of the three-dimensional object that is not semi-transparently displayed.

  In this case, as described in step S102 of FIG. 2 in the first embodiment, the ID assigning unit 31 performs each surface rendered based on the shape information of the three-dimensional shape that is not translucently displayed on the three-dimensional object. Instead of the original color information, a surface ID composed of different color information is assigned to each surface to be drawn based on the shape information of the three-dimensional shape of the three-dimensional object that is not translucently displayed. Make it identifiable. Therefore, in the shape information of the three-dimensional shape that is not translucently displayed of the three-dimensional object to which the color information indicating the surface ID is assigned instead of the color information of the original surface generated by the ID assigning unit 31, the surface information The color information does not represent the color of the original surface, but is convenient for identifying the surface. The control unit 41 stores, in the first data storage unit 11, the shape information of the three-dimensional shape that is not translucently displayed on the three-dimensional object to which the color information indicating the surface ID obtained by the ID providing unit 31 is added.

Next, in step S164, the control means 41 is the same as step S103 shown in FIG. 2, and the three-dimensional object to which the color information indicating the surface ID is assigned from the first data storage means 11 by the ID assigning means 31. The hidden surface processing means 32 displays the shape information and display conditions of the three-dimensional shape that is not translucently displayed.
To read and apply hidden surface processing.

  The hidden surface processing means 32 performs hidden surface processing and shading processing on the shape information of the three-dimensional shape that is not semi-transparently displayed for the three-dimensional object to which the color information indicating the surface ID is assigned instead of the original surface color information. Then, three-dimensional image information (image information 2) of the three-dimensional object to which color information indicating the surface ID is assigned for each pixel and not translucently displayed is generated. The control means 41 is provided with color information indicating the surface ID generated by the hidden surface processing means 32, in addition to the above-described three-dimensional shape two-dimensional color image information (image information 1) that is not semi-transparently displayed on the three-dimensional object. The image information (image information 2) of the three-dimensional object that is not semi-transparently displayed on the three-dimensional object that is displayed is also used as the second data storage means as image information for identifying the surface of the three-dimensional object that is not semi-transparently displayed. 12 to store.

  Next, in step S165, the control means 41 generates image information (image information 2) for identifying a three-dimensional surface of the three-dimensional object to which the color information indicating the surface ID is not translucently displayed. The image generation means 33 generates image information (image information 3) representing a three-dimensional contour line, ridge line, and / or interphase line that is not translucently displayed on the three-dimensional object.

  A method of generating image information representing a three-dimensional contour line, ridge line, and / or interphase line that is not semi-transparently displayed on the three-dimensional object by the image generation means 33 is shown in step S104 shown in FIG. 2 or FIG. The method of step S124 is used.

  The image information representing the contour line, ridge line, and / or interphase line of the three-dimensional object that is generated by the image generation unit 33 and is not translucently displayed is stored in the third data storage unit 13 as image information 3. Remembered.

  Next, in step S166, the control means 41 changes the three-dimensional shape of the three-dimensional object that is not translucently displayed, reflecting the color information of the original surface of the three-dimensional object stored in the second data storage means 12. Two-dimensional color image information (image information 1) which is image information, and a three-dimensional contour line which is not translucently displayed of the three-dimensional object generated by the image generation unit 33 stored in the third data storage unit 13 , Ridge lines, and / or line drawing image information (image information 3), which is image information representing the interpenetrating line, is read by the image superimposing means 34 to perform the superimposing process of both image information.

  The image superimposing means 34 reads both pieces of image information, and adds a three-dimensional outline of the three-dimensional object not displayed semi-transparently to the two-dimensional color image information (image information 1) of the three-dimensional object not displayed semi-transparently. , Edge line and / or line drawing image information (image information 3) representing a line of intersection is overwritten to generate two-dimensional color output image information (image information 4) of a three-dimensional shape that does not translucently display a three-dimensional object. . The generated two-dimensional color output image information (image information 4) includes a three-dimensional shape of a two-dimensional color image (image information 1) that is not translucently displayed as an edge, an edge, and / or a phase. This is further emphasized by the entry of line drawing image information (image information 3) representing a penetration line, and is stored in the third data storage means 13.

  Next, in step S167, the control unit 41 does not display the three-dimensional object in which the contour line, the ridge line, and / or the interphase line stored in the third data storage unit 13 are translucently displayed. The shape information of the two-dimensional output image (image information 4) is read by the semi-transparent image generation means 37, and the color information of the original surface of the three-dimensional shape to be displayed semi-transparently from the first data storage means 11 is displayed. The semi-transparent image generation means 37 reads the shape information and the display conditions to which the

The translucent image generating means 37 is for 2-dimensional output image information (image information 4) in which contour lines, ridge lines, and / or interphase lines are entered for a three-dimensional shape of a three-dimensional object that is not translucently displayed. Only the 3D object to be displayed semi-transparently for the entire shape of the 3D object by performing the hidden surface processing on the shape information to which the color information of the original surface of the 3D object to be displayed translucently of the 3D object is provided. Two-dimensional color image information (image information 5) in which no contour lines, ridge lines, and / or interphase lines are written is generated.

  In this case, the two-dimensional color image information (image information 5) of the entire three-dimensional shape of the three-dimensional object in which the contour line, the ridge line, and / or the interpenetration line are not entered only for the three-dimensional shape to be translucently displayed is semi-transparent. If the surface of the three-dimensional shape to be transparently displayed is close to the viewpoint (that is, the front) with respect to the surface of the three-dimensional shape not to be semitransparently displayed, that is, the surface of the three-dimensional shape to be semitransparently displayed is not three-dimensionally displayed. It appears without being erased by the surface of the shape. On the other hand, when the surface of the three-dimensional shape that is not semitransparently displayed is closer to the viewpoint (that is, in front) than the surface of the three-dimensional shape that is semitransparently displayed, the surface of the three-dimensional shape that is semitransparently displayed is semitransparent. The hidden surface is erased by the surface of the three-dimensional shape that is not displayed and does not appear.

  Therefore, the semi-transparent image generating means 37 provides two-dimensional color image information of the entire three-dimensional shape of the three-dimensional object in which no contour line, ridge line, and / or interphase line are entered only for the three-dimensional shape to be displayed semi-transparently. When the image information 5) is generated, the following processing is performed on the color of the surface of the three-dimensional shape to be translucently displayed.

  The semi-transparent image generating means 37 has a three-dimensional shape that is not translucently displayed by the image information 4 described above for each surface of the entire shape of the three-dimensional object subjected to the hidden surface processing. If it is closer to the viewpoint than the surface, the original pixel color of the three-dimensional shape surface that is not semi-transparently displayed and the original pixel color of the three-dimensional shape surface that is semi-transparently displayed are displayed 3 By changing and determining the original pixel color of the surface portion (that is, the hidden surface erasure surface portion) that overlaps the surface of the three-dimensional shape that is not translucently displayed among the three-dimensional surfaces, by a predetermined method, Only for this semi-transparent portion of the three-dimensional surface of the three-dimensional object to be displayed semi-transparently, the original pixel color of the surface is changed.

  Here, the predetermined method means, for example, that the original pixel color of the surface of the three-dimensional shape not overlappingly displaying the semi-transparent display and the original pixel color of the surface of the three-dimensional shape displaying semi-transparent are set to be constant. It is determined by using a so-called blending process of mixing at a ratio. The original pixel color of the three-dimensional shape surface to be displayed semi-transparently used in this blending process is the original surface color given to the three-dimensional shape information of the three-dimensional shape to be displayed semi-transparently of the three-dimensional object. Information.

  Then, the control unit 41 3 of the three-dimensional object in which the contour line, the ridge line, and / or the interlace line are not entered only for the three-dimensional shape that is generated by the semi-transparent image generation unit 37 and is not translucently displayed. Two-dimensional color image information (image information 5) of the entire three-dimensional shape is stored in the third data storage means 13.

  Next, in step S168, the control unit 41 adds shape information to which the color information of the original surface of the three-dimensional shape that is not translucently displayed of the three-dimensional object is added from the first data storage unit 11, and the translucent display. The shape information to which the color information of the original surface of the entire three-dimensional object, which is formed from the shape information to which the color information of the original surface of the three-dimensional shape is added, is read by the ID assigning means 31.

As described in step S102 of FIG. 2, the ID assigning means 31 is drawn based on the shape information of the entire three-dimensional object, that is, the three-dimensional shape that is not displayed semi-transparently and the three-dimensional shape that is displayed semi-transparently. Instead of the original color information of each surface, for example, a consistent serial number from “1” is given, and each surface that is drawn based on the shape information of the entire three-dimensional object has a surface ID composed of different color information for each surface. Is added so that each surface can be identified. Control means 41
Stores the shape information of the entire three-dimensional object to which the color information indicating the surface ID obtained by the ID providing unit 31 is added in the first data storage unit 11.

  Next, in step S169, the control means 41 is the same as step S103 shown in FIG. 2, and the three-dimensional object to which the color information indicating the surface ID is assigned from the first data storage means 11 by the ID assigning means 31. The entire shape information and display conditions are read by the hidden surface processing means 32 to perform the hidden surface processing. The hidden surface processing means 32 performs hidden surface processing and shading processing on the shape information of the entire three-dimensional object to which color information indicating the surface ID is given instead of the original surface color information, and for each pixel. Image information of the entire three-dimensional object to which color information indicating the surface ID is assigned is generated. The control means 41 obtains the image information of the entire 3D object to which the color information indicating the surface ID generated by performing the hidden surface processing by the hidden surface processing means 32 is added, and the base image of the image information of the entire 3D object. Is stored in the second data storage means 12 as image information for image identification (image information 6).

  Next, in step S170, the control unit 41 is given color information indicating the surface ID on which the hidden surface processing has been performed on the entire three-dimensional shape of the three-dimensional object stored in the second data storage unit 12. Image information (image information 6) is read by the image generation unit 33, and the image generation unit 33 displays image information representing contour lines, ridge lines, and / or interphase lines for the entire three-dimensional shape of the three-dimensional object. (Image information 7) is generated.

  The method of generating image information representing the contour line, the ridge line, and / or the interpenetration line for the entire three-dimensional shape of the three-dimensional object by the image generating means 33 is the step shown in step S104 shown in FIG. 2 or the step shown in FIG. The method of S124, that is, the method described in step S155 of FIG. 8 is used.

  The image information (image information 7) representing the contour line, the ridge line, and / or the interphase line for the entire three-dimensional shape of the three-dimensional object generated by the image generating means 33 is a line drawing of the entire three-dimensional shape of the three-dimensional object. The image information is stored in the third data storage unit 13.

  Next, in step S171, the control means 41 performs contour lines, ridge lines, and / or inconsistency only for the three-dimensional shape not translucently displayed that is stored in the third data storage means 13 generated in the previous step S167. Two-dimensional color image information (image information 5) of the entire three-dimensional shape of the three-dimensional object in which no line is written, and the three-dimensional object stored in the third data storage means 13 generated in the previous step S170. The image superimposing means 34 reads the line drawing image information (image information 7) representing the contour line, the ridge line, and / or the interpenetration line for the entire three-dimensional shape.

  The image superimposing means 34 performs two-dimensional color image information (image information 5) of the entire three-dimensional shape of a three-dimensional object in which no contour line, ridge line, and / or interphase line are entered only for the three-dimensional shape that is not translucently displayed. In addition, the line drawing image information (image information 7) representing the contour line, the edge line, and / or the interpenetration line for the entire three-dimensional shape of the three-dimensional object is overwritten, and the contour line for the entire three-dimensional shape of the three-dimensional object 2D color output image information (image information 8) including a translucent display while emphasizing the ridge line and / or the interphase line is generated. The generated two-dimensional color output image information is stored in the third data storage unit 13.

  Therefore, according to the drawing method of the present embodiment, it is possible to easily generate a color image including a translucent display while enhancing a contour line, a ridge line, and / or an interphase line of a three-dimensional object.

[Fifth Embodiment]
Next, as a fifth embodiment of the present invention, a drawing method for generating a monochrome line drawing image or a color image of a three-dimensional object in which contour lines, ridge lines, and / or interphase lines are described is desired to be generated. A drawing method in image generation when the number of pixels of an image is larger than the number of pixels of an image that can be processed by a PC or GWS will be described with reference to the drawings.

  The three-dimensional object image generation system employing the contour line, ridge line, and / or phase line drawing method according to the present embodiment is a three-dimensional image employing the drawing method according to the first embodiment shown in FIG. An area dividing unit 35 for dividing an area of an image to be generated with respect to the object image generating system or the three-dimensional object image generating system adopting the drawing method according to any one of the second to fourth embodiments described above. The image integration means 36 for integrating the divided images is further provided. Therefore, since the other configurations are the same in the present embodiment, detailed description of the system configuration is omitted, and the same components are described using the same names and symbols shown in FIG. .

  FIG. 11 shows the processing of the method for generating an image of a three-dimensional object in which contour lines, ridge lines, and / or interpenetrating lines are described by the three-dimensional object image generation system employing the drawing method according to the present embodiment. It is the flowchart explaining the flow.

  First, the control means 41 is supplied with the shape information and display conditions of the three-dimensional object by the input / output means 21 and stores them in the first data storage means 11 in advance. If there is an area division condition consisting of the number of pixels on the screen of PC and GWS, the number of pixels of the image to be generated and the number of pixels of the screen of PC or GWS are supplied via the input / output means 21. Is stored in the first data storage means 11 as an area division condition.

  When the input / output means 21 supplies the shape information and the display conditions of the three-dimensional object, the control means 41 stores them in the first data storage means 11 and the above-described pixel of the image to be generated. If the area division condition consisting of the number of pixels and the number of pixels of the PC or GWS screen is preset, in step S181, the area division condition and the shape of the three-dimensional object supplied from the input / output means 21 are obtained. Information and display conditions are read by the area dividing means 35.

  The area dividing unit 35 appropriately divides the image into a plurality of divided image areas based on the relationship between the number of pixels of the image to be generated as the area dividing condition and the number of pixels of the PC or GWS screen, and viewing from the viewpoint position as the display condition The shape information of the three-dimensional object corresponding to each of the image regions is divided for each of the divided image regions to generate division information of the shape information of the three-dimensional object.

  The control means 41 stores the generated division information in the first data storage means 11 as a display condition.

  Next, in step S182, the control means 41 obtains the shape information of the three-dimensional object and the division information as the display condition from the first data storage means 11 as the hidden surface processing means 32 and, if necessary, the semitransparent image generation means. 37, after which the processing described in the first to fourth embodiments is performed by each unit, and image generation is performed for each of the divided divided image areas according to the division information as the display condition. 2D output image information of each divided image area is stored in the third data storage means 13.

  In step S183, the control unit 41 causes the image integration unit 36 to read the two-dimensional output image information of each of the divided divided image areas stored in the third data storage unit 13. Based on this, the image integration means 36 integrates the two-dimensional output image information of each of the divided image areas to generate one two-dimensional output image information, and uses the generated two-dimensional output image information as the two-dimensional output integrated image information. Is stored in the data storage means 13.

According to the three-dimensional object image generation system according to the present embodiment, for example, when the resolution of the printer is higher than the number of pixels on the screen of the PC or GWS, there is an effect that the resolution of the printer can be maximized. That is, it is possible to generate a high-resolution image without being restricted by the limitation of the PC or GWS screen.

  For example, when printing on A4 size paper, if the resolution of the printer is 200 dpi, the number of pixels of about 2300 × 1600 is required, and if the number of pixels on the PC or GWS screen is 1280 × 1024, the pixels of the image to be generated By setting the area division condition such that the number of pixels is 2300 × 1600 and the number of pixels of the PC or GWS screen is 1280 × 1024, the area division unit 35 can display 3 as viewed from the viewpoint position as the display condition. The image area based on the shape information of the three-dimensional object is divided into four parts to generate two-dimensional output image information for each of the divided image areas having the number of pixels of 1150 × 800. By integrating the two-dimensional output image information for each, an image of the entire three-dimensional object having 2300 × 1600 pixels for output to the printer is generated. Door can be.

  The embodiment of the contour line, ridge line, and / or phase line drawing method and the image data generation system using the drawing method according to the present invention is as described above, but its specific procedure and configuration. Is not limited to the embodiment described above.

  For example, the contour line, ridge line, and / or phase line drawing method according to the present invention, and the image data generation system using the drawing method include a pixel to be compared and generates a contour image therefrom. In contrast to this, for example, on the contrary due to the relationship of resolution, first, after determining the drawing area / resolution of the image to be generated, a comparison image required for image generation is generated, and drawing is performed based on that Even if it is, it is of course applicable. In the latter case, if the user thinks that a low resolution is sufficient, the comparative image is also generated at a low resolution, and the resulting image is also a low resolution, while a high resolution can be realized in the same manner.

  Also, the contour line, ridge line, and / or interphase line drawing method and image data generation system according to the above-described embodiment can be used to generate a three-dimensional object shape information and a three-dimensional object shape information. It is also possible to configure a 3D CAD system or a 3D object viewer system by applying to a viewer system to be confirmed.

According to the present invention, it is possible to construct a higher-speed image generation system by implementing a part of functions necessary for image generation as hardware.
Further, by adding an image editing function based on the generated image data, it can be applied to a high-precision CG (Computer Graphics) and animation creation system.

It is a functional block diagram which shows one Example of the image generation system of the three-dimensional object which employ | adopted the drawing method by the 1st Embodiment of this invention. 2 is a flowchart illustrating a flow of processing for generating a black and white line drawing image of a three-dimensional object in which contour lines, ridge lines, and / or interphase lines are described by the three-dimensional object image generation system illustrated in FIG. 1. FIG. 3 is a PAD showing details of processing for generating image information representing the contour line, ridge line, and / or interphase line of a three-dimensional object by the image generation means described in FIG. 2. FIG. It is explanatory drawing of the positional relationship of the pixel produced | generated by the image production | generation means demonstrated in FIG. 3, and the pixel produced | generated by the hidden surface process means. It is the figure which showed the example of a production | generation of the image information showing the outline of a three-dimensional object, the ridgeline, and / or an interpenetration line by the three-dimensional object image generation system which employ | adopted the drawing method by this Embodiment. A method for generating a monochrome line drawing image of a three-dimensional object in which a contour line, a ridgeline, and / or an interphase line are described by an image generation system of the three-dimensional object employing the drawing method according to the second embodiment of the present invention It is the flowchart explaining the flow of the process of. FIG. 7 is a PAD showing details of processing for generating image information representing the contour line, ridge line, and / or interphase line of a three-dimensional object by the image generation means described in FIG. 6. FIG. Processing of a method for generating a color image of a three-dimensional object in which a contour line, a ridge line, and / or an interphase line are emphasized by an image generation system of the three-dimensional object employing a drawing method according to the third embodiment of the present invention It is the flowchart explaining the flow. It is the figure which showed the example of a production | generation of the two-dimensional color output image information by the image production | generation system of the three-dimensional object which employ | adopted the drawing method by this Embodiment. The flowchart explaining the flow of the process of the method of producing | generating the image of a contour line, a ridgeline, and / or an incoherent line by the image generation system of the three-dimensional object which employ | adopted the drawing method by the 4th Embodiment of this invention. is there. Processing of a method for generating an image of a three-dimensional object in which a contour line, a ridge line, and / or an interphase line are described by an image generation system of a three-dimensional object employing a drawing method according to a fifth embodiment of the present invention It is the flowchart explaining the flow.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 1st data storage means 12 2nd data storage means 13 3rd data storage means 21 Input / output means 31 ID provision means 32 Hidden surface processing means 33 Image generation means 34 Image superimposition means 35 Area division means 36 Image integration means 37 Translucent image generating means

Claims (11)

A method for drawing a contour line, a ridge line, and / or an interpenet line that outputs a visible one of a contour line, a ridge line, and / or an interpenet line of a three-dimensional object as a two-dimensional image,
A surface identification information providing step of giving different surface identification information to each surface of the three-dimensional object to be drawn;
A hidden surface processing step of generating image information of the three-dimensional object by performing a hidden surface process on the shape information of the three-dimensional object to which the surface identification information is added in the surface identification information adding step;
For each pixel of the image information of the three-dimensional object generated in the hidden surface processing step, image information representing a contour line, a ridge line, and / or an interstitial line is obtained based on a difference in surface identification information between adjacent pixels. have a resulting line drawing image generation step,
The line drawing image generation step includes:
Among the surface identification information for each of the four adjacent pixels of the image information of the three-dimensional object generated in the hidden surface processing step, the surface identification information of at least one pixel is the surface identification information of the remaining pixels. If different, one pixel forming image information representing a contour line, a ridge line, and / or a continuous line is generated so as to correspond to the center position of the four pixels. How to draw. A method for drawing a contour line, a ridge line, and / or an interpenet line that outputs a visible one of a contour line, a ridge line, and / or an interpenet line of a three-dimensional object as a two-dimensional image,
A surface identification information providing step of giving different surface identification information to each surface of the three-dimensional object to be drawn;
The hidden surface processing is performed on the shape information of the three-dimensional object to which the surface identification information is added in the surface identification information adding step to generate image information of the three-dimensional object, and the image information from the viewpoint of each pixel is generated. Hidden surface process to prepare distance information,
For each pixel of the image information of the three-dimensional object generated in the hidden surface processing step, a contour line, a ridge line, and / or a difference based on a difference in surface identification information between adjacent pixels and a difference in distance information from the viewpoint. Alternatively, a line drawing image generation step for generating image information representing an interphase line,
I have a,
The line drawing image generation step includes:
Surface identification information regarding four pixels adjacent to each other in the image information of the three-dimensional object generated in the hidden surface processing step is defined as one pixel forming image information representing a contour line, a ridge line, and / or an interstitial line. And a comparison with respect to a reference value regarding a difference in distance information from the viewpoint between the two pixels in the four pixels . The surface identification information providing step includes
When expressed in combination with one face a plurality of approximate surface in the three-dimensional object drawing according to claim 1, wherein applying the same surface identification information to the plurality of approximate surface respectively Method. The surface identification information providing step includes
Surface identification information is given as surface color information,
The line drawing image generation step includes:
Drawing method according to any one of claims 1 to 3, characterized in that to obtain the surface identification information as the color information of the pixel. Generates image information representing contour lines, ridge lines, and / or interphase lines generated by the line drawing image generation process by performing hidden surface processing on the shape information of the three-dimensional object to which the original color information is added. 5. The drawing method according to claim 1, further comprising an image superimposing step of overwriting the original image information of the three-dimensional object. A division step of dividing an image area to be generated into a plurality of image areas;
The hidden surface processing step and the line drawing image generation step are executed for each of the plurality of image regions divided by the division step,
An image integration step of integrating image information representing contour lines, ridge lines, and / or interphase lines generated by the line drawing image generation step for each of the plurality of image regions. Item 6. The drawing method according to any one of Items 1 to 5 . Image data generation system and generating an image data of a three-dimensional object using the preceding claims outline according to any ridgeline, and / or interpenetrating wire drawing process. Means for performing hidden surface processing on shape information of a three-dimensional shape not translucently displayed among the three-dimensional objects, and generating image information about a three-dimensional shape not translucently displayed among the three-dimensional objects;
Using the drawing method according to claim 1 for the shape information of a three-dimensional shape that is not semi-transparently displayed among three-dimensional objects, the contour line, ridge line, and / or phase of the three-dimensional shape that is not semi-transparently displayed. Means for generating image information representing a penetration line;
The image information about the three-dimensional shape that is not translucently displayed among the three-dimensional objects is superimposed on the image information that represents the contour line, the ridge line, and / or the interphase line of the three-dimensional shape that is not translucently displayed.
Means for generating superimposed image information about a three-dimensional shape of a three-dimensional object that is not semi-transparently displayed;
The three-dimensional shape of the three-dimensional object to be displayed semi-transparently is subjected to hidden surface processing on the superimposed image information of the three-dimensional shape of the three-dimensional object not to be displayed semi-transparently. Of the three-dimensional surface to be displayed semi-transparently among the three-dimensional objects closer to the viewpoint with respect to the superimposed image information about the three-dimensional shape not to be overlapped, the surface overlapping the superimposed image information about the three-dimensional shape not to be semi-transparently displayed The original color of the pixel of the part is changed based on the color based on the superimposed image information for the three-dimensional shape that is not translucently displayed, and only the three-dimensional shape that is semitransparently displayed is a contour line, a ridgeline, and / or an interphase line Means for generating image information of the entire three-dimensional shape of a three-dimensional object not filled with
Using the drawing method according to claim 1, image information representing contour lines, ridge lines, and / or interphase lines for the entire three-dimensional shape of the three-dimensional object is used for the entire three-dimensional shape of the three-dimensional object. Means for generating;
Only for the three-dimensional shape to be displayed semi-transparently, the image information of the entire three-dimensional shape of the three-dimensional object in which no contour line, ridge line, and / or interphase line is entered is added to the three-dimensional shape of the three-dimensional object. Means for superimposing image information representing contour lines, ridge lines, and / or interphase lines, and generating superimposed image information about the entire three-dimensional shape of the three-dimensional object;
An image data generation system comprising: Means for performing hidden surface processing on shape information of a three-dimensional shape not translucently displayed among the three-dimensional objects, and generating image information about a three-dimensional shape not translucently displayed among the three-dimensional objects;
Using the drawing method according to claim 2 for the shape information of a three-dimensional shape that is not semi-transparently displayed among three-dimensional objects, the contour line, ridge line, and / or phase of the three-dimensional shape that is not semi-transparently displayed. Means for generating image information representing a penetration line;
Superimposing image information representing a contour line, a ridge line, and / or an interphase line of the three-dimensional shape not displayed semi-transparently on the image information about the three-dimensional shape not displayed semi-transparently of the three-dimensional object,
Means for generating superimposed image information for a three-dimensional shape of a three-dimensional object that is not semi-transparently displayed;
The three-dimensional shape of the three-dimensional object to be displayed semi-transparently is subjected to hidden surface processing on the superimposed image information of the three-dimensional shape of the three-dimensional object not to be displayed semi-transparently. Of the three-dimensional surface to be displayed semi-transparently among the three-dimensional objects closer to the viewpoint with respect to the superimposed image information about the three-dimensional shape not to be overlapped, the surface overlapping the superimposed image information about the three-dimensional shape not to be semi-transparently displayed The original color of the pixel of the part is changed based on the color based on the superimposed image information for the three-dimensional shape that is not translucently displayed, and only the three-dimensional shape that is semitransparently displayed is a contour line, a ridge line, and / or an interphase line. Means for generating image information of the entire three-dimensional shape of a three-dimensional object not filled with
Using the drawing method according to claim 2, image information representing contour lines, ridge lines, and / or interphase lines for the entire three-dimensional shape of the three-dimensional object is applied to the entire three-dimensional shape of the three-dimensional object. Means for generating;
Only for the three-dimensional shape to be displayed semi-transparently, the image information of the entire three-dimensional shape of the three-dimensional object in which no contour line, ridge line, and / or interphase line are entered is added to the three-dimensional shape of the three-dimensional object. Means for superimposing image information representing contour lines, ridge lines, and / or interphase lines, and generating superimposed image information about the entire three-dimensional shape of the three-dimensional object;
An image data generation system comprising: Using the method of drawing according to any one of claims 1 to 6, the three-dimensional CAD system and generates a drawing image data. Using the method of drawing according to any one of claims 1 to 6, viewer system and generates a drawing image data.

Images