JPH0863620A - Method and device for processing graphic - Google Patents

Abstract

PURPOSE: To allow a graphic processor to automatically recognize a specified face by setting up a face having the maximum inclusion rate of the coordinate position of a cursor moving on the surface of a three-dimensional graphic in a closed graphic projected into a virtual plane of the three-dimensional graphic surface as a specified face. CONSTITUTION: When an operator indicates a face to be specified by moving a cursor on the face, the inclusion rate of a three-dimensional graphic face specified by the coordinate position of the indicated cursor in a closed graphic projected into a virtual plane is detected and a face having the largest inclusion ratio is determined as the specified face. Namely a cursor position detecting means 12 sequentially detects the coordinate position of the cursor in accordance with the movement of the cursor, a coordinate converting means 13 projects a point or an element on three-dimensional space into optional two-dimensional space and an inclusion relation judging means 13 judges whether a certain point on the two-dimensional plane exists on the inside or outside of a certain closed two-dimensional graphic on the same plane. Consequently a face to be specified can be selected only by moving the cursor on the face to be specified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a computer aided design.
sign, hereinafter abbreviated as CAD. The present invention relates to a graphic processing method and a graphic processing apparatus used for design work utilizing a computer.

[0002]

2. Description of the Related Art In recent years, mechanical CAD devices, computer graphic devices, etc. have been evolving from the conventional two-dimensional display to a more realistic three-dimensional display, and the demand for them has greatly increased. There is. However, the unique new concept of 3D display complicates the operation required by the user, making the transition from 2D to 3D difficult.

A conventional graphic processing device will be described below. FIG. 10 is a functional block diagram showing the configuration of a conventional graphic processing device.

In FIG. 10, 1 is an input unit for inputting character data and numbers, 2 is a display unit for displaying characters or figures input by the input unit 1, and 3 is coordinates displayed on the display unit 2. Coordinate designation section for selecting graphic elements, 4 is input section 1
Alternatively, a storage unit 5 for storing figures, characters, numbers, etc. input from the coordinate display unit 3 is a data acquisition means for fetching the data of the graphic elements stored in the storage unit 4 into the control unit 7, 6
Is a designated surface determining means for determining a designated surface from a point or a ridge line input from the coordinate designating section 3, and 7 is a control section for performing overall control.

The operation of the graphic processing apparatus configured as described above will be described below with reference to the drawings. 11,
12 and 13 are flowcharts showing the determination of the designated surface of the conventional graphic processing apparatus. FIG. 14A is a diagram showing points selected for determining the designated surface. here,
Reference numeral 8 is a three-dimensional figure which is a target of the designated surface selection, and 9 is a point selected for determining the designated surface. FIG. 14B is a diagram showing the ridge line selected to determine the designated surface.
Here, 8 is a three-dimensional figure that is the target of the designated surface selection,
Reference numeral 10 is a ridge line selected to determine the designated surface. FIG. 14C is a diagram showing the ridge line selected to determine the designated surface. Here, 8 is a three-dimensional figure which is the target of the designated surface selection, and 11 is a ridge line selected to determine the designated surface. In FIG. 11, first, as shown in FIG. 14A, the coordinate designating section 3 selects three points located at the end of the designated surface (S1). Next, the coordinates of the three points selected in S1 are acquired by the control unit 7 (S
2). Next, the data of the target three-dimensional figure 8 is acquired from the storage unit 4 by the control unit 7 (S3). Next, the surface to be calculated is set (S4). Next, it is determined whether the calculation is completed (S5). If YES, error processing is performed (S6), and the operation ends. If NO, it is determined whether the three points belong to the calculation target surface (S7). If NO, the next surface is set as the calculation target surface (S8) and S5 is executed. If YES, it is determined that the surface to which the three points belong is the designated surface (S9), and the process ends.

Next, the operation of determining the designated surface of another conventional graphic processing apparatus will be described with reference to the drawings. In FIG. 12, first, as shown in FIG. 14B, two ridge lines 10 located at the end of the designated surface are selected (S101).
Next, the coordinates of the two ridgelines 10 selected in S101 are acquired by the control unit 7 (S102). Next, the data of the target three-dimensional figure 8 stored in the storage unit 4 is acquired by the control unit 7 (S103). Next, the surface of the three-dimensional figure 8 to be calculated is set (S104). Next, it is determined whether the calculation is completed (S105). If YES, error processing is performed (S106), and then the processing ends. N
If it is O, it is determined whether or not the two ridge lines 10 belong to the calculation target surface (S107). If NO, then the surface is set as the calculation target surface (S108), and then S105 is executed. If YES, it is determined that the surface to which the two ridge lines 10 belong is designated (S109), and then the processing ends.

The operation of determining the designated surface of another conventional graphic processing apparatus will be described with reference to the drawings. In FIG. 13, first, as shown in FIG. 14C, one ridge line 11 located at the end of the designated surface is selected (S201).
Next, the control unit 7 acquires the coordinates of the ridgeline selected in S201 (S202). Next, the data of the target three-dimensional figure 8 stored in the storage unit 4 is acquired by the control unit 7 (S203). Next, the surface of the three-dimensional figure 8 to be calculated is set (S204). Next, it is determined whether the calculation is completed (S205). If YES, error processing is performed (S206), and then the processing ends. If NO, it is determined whether the ridgeline 11 belongs to the calculation target surface (S207). If NO, the next surface is set as the calculation target surface (S209) and then S205 is executed. YE
If it is S, it is determined whether two candidate surfaces have been found (S208). If NO, the next surface is set as the calculation target surface (S209) and then S205 is executed.
If YES, the operator selects the designated surface from the two candidate surfaces (S210). Next, after it is determined that the surface designated by the worker is the designated surface (S211), the process ends.

[0008]

However, in the above-mentioned conventional graphic processing apparatus, when a surface of a three-dimensional graphic is designated, it is necessary to perform a plurality of selection operations, and the surface itself is not selected as the target surface selecting means. However, there is a problem that it is difficult to intuitively understand because the operator selects a plurality of ridge lines representing the surface and a plurality of points on the surface.

Further, the above-described conventional graphic processing method has a problem in that it requires a large number of operations, resulting in poor work efficiency. In addition, since the designated surface is not directly designated, it is difficult to intuitively understand.

The present invention solves the above-mentioned conventional problems, and an excellent graphic processing method and graphic in which the device can automatically recognize the specified surface by allowing the user to directly specify the surface in the three-dimensional graphic. An object is to provide a processing device.

[0011]

In order to achieve this object, a graphic processing method according to claim 1 of the present invention is a cursor for sequentially detecting the coordinate position of a cursor to be moved on the surface of a three-dimensional graphic to be designated. The position detection step, the inclusion rate detection step of detecting the rate at which the coordinate position detected in the cursor position detection step is included in the projection closed figure on the virtual plane of the surface of the three-dimensional figure, and the inclusion rate detection step. And a designated surface determining step of determining the surface having the largest inclusion rate as the designated surface.

According to a second aspect of the present invention, there is provided a graphic processing method, wherein a cursor position detecting step of sequentially detecting a coordinate position of a cursor moving on a surface of a desired three-dimensional figure and a coordinate position detected by the cursor position detecting step. A closed figure creating step for creating an inscribed closed figure; and an overlapping area rate detecting step for detecting an area rate where the closed figure created in the closed figure creating step overlaps with a projected closed figure on a virtual plane of a three-dimensional surface. The designated surface determining step of determining the surface having the largest area ratio detected by the overlapping area ratio detecting step as the specified surface.

According to a third aspect of the present invention, there is provided a graphic processing method, wherein a cursor position detecting step of sequentially detecting a coordinate position of a cursor moving on a surface of a desired three-dimensional graphic, and a center of gravity of each surface of the three-dimensional graphic are calculated. Center-of-gravity detection step, point-to-point distance calculation step for calculating the sum of distances between the coordinate position detected by the cursor position detection step on the projection plane onto the virtual plane and the center of gravity detected by the center-of-gravity detection step, and point-to-point distance calculation The designated surface determining step of determining the surface having the smallest sum of the distances calculated by the step as the designated surface.

According to a fourth aspect of the present invention, there is provided a graphic processing device in which a cursor position detecting means for sequentially detecting a coordinate position of a cursor to be moved on a surface of a desired three-dimensional graphic and a coordinate position detected by the cursor position detecting means. Projection of a surface of a three-dimensional figure onto a virtual plane. A coverage rate detecting means for detecting a rate included in a closed figure, and a designated surface determination for determining a surface having the highest coverage rate detected by the coverage rate detecting means as a designated surface. And means.

According to a fifth aspect of the present invention, there is provided a graphic processing apparatus, wherein cursor position detecting means for sequentially detecting a coordinate position of a cursor to be moved on the surface of a desired three-dimensional figure, and coordinate position detected by the cursor position detecting means. A closed figure creating means for creating an inscribed closed figure; and an overlapping area rate detecting means for detecting an area rate in which the closed figure created by the closed figure creating means overlaps with a projected closed figure on a virtual plane of a three-dimensional surface. The designated area determining means determines the surface having the largest area rate detected by the overlapping area rate detecting means as the designated surface.

According to a sixth aspect of the present invention, there is provided a graphic processing apparatus for calculating cursor position detecting means for sequentially detecting coordinate positions of a cursor for moving on a surface of a three-dimensional graphic to be designated, and a center of gravity of each surface of the three-dimensional graphic. Center-of-gravity detection means, point-to-point distance calculation means for calculating the sum of distances between the coordinate position detected by the cursor position detection means on the projection plane onto the virtual plane and the center of gravity detected by the center-of-gravity detection means, and point-to-point distance calculation And a designated surface determining means for determining the surface having the smallest sum of distances calculated by the means as the designated surface.

[0017]

With this configuration, the operator designates the designated surface by moving the cursor on the designated surface. The coordinate position of the designated cursor detects the ratio of the surface of the target three-dimensional figure included in the projected closed plane to the virtual plane, and designates the surface with the largest inclusion rate. You can decide.

With this configuration, the operator designates a designated surface by moving the cursor on the designated surface. The overlapping area ratio between the closed figure that inscribes the coordinate position of the designated cursor and the projected closed figure of the surface of the target 3D figure on the virtual plane was detected, and the surface with the largest overlapping area rate was specified. Can be determined to be a face.

Further, with this structure, the operator designates a designated surface by moving the cursor on the designated surface. On the projection plane onto the virtual plane, calculate the sum of the distance between the coordinate position of the specified cursor and the center of gravity of each surface of the target 3D figure, and specify the surface with the smallest total distance as the specified surface. You can decide.

[0020]

An embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a functional block diagram showing the configuration of a graphic processing apparatus in a first embodiment of the present invention.

In FIG. 1, 1 is an input unit, 2 is a display unit,
Reference numeral 3 is a coordinate designation unit, 4 is a storage unit, and 5 is a data acquisition means. These are the same as in the conventional example, and the same reference numerals are given and the description thereof is omitted.

Reference numeral 12 is a cursor position detecting means for successively detecting the coordinate position of the cursor as the cursor is the coordinate designating portion 3, and 13 is a coordinate converting means for projecting points or elements in the three-dimensional space onto an arbitrary two-dimensional space. Reference numeral 14 is an inclusive relation judging means for judging whether a certain point on the two-dimensional plane is inside or outside a closed two-dimensional figure on the same plane, and 15 is a control section for controlling the entire apparatus.

A keyboard or the like is used as the input unit 1. As the display unit 2, a CRT, a liquid crystal display, a plasma display or the like is used. A mouse, a pointer, a trackball, or the like is used as the coordinate designation unit 3. As the storage unit 4, a floppy disk, a hard disk, a magneto-optical disk, a silicon disk or the like is used. As the control unit 15, a one-chip microcomputer device having a built-in peripheral control circuit is inexpensive, and the device can be made compact, so that it is preferably used.

A graphic processing method of the graphic processing apparatus configured as described above will be described below with reference to the drawings.
FIG. 2 is a flow chart showing the determination of the designated surface of the graphic processing apparatus in the first embodiment of the present invention. FIG. 3A is a diagram showing a state in which the designated surface of the present invention is designated by a cursor. Here, 8 is a three-dimensional figure that is the target of the designated surface selection, and 17 is the trajectory of the cursor. FIG. 3B is a diagram showing a projection closed figure of a three-dimensional figure whose designated surface is designated by a cursor on a virtual plane according to the present invention. Here, 8 is a three-dimensional figure that is the target of the designated surface selection, 16 is a virtual plane, and 17 is the trajectory of the cursor. FIG. 4A is a diagram showing coordinate positions on the trajectory of the cursor of the present invention. Here, 8 is a three-dimensional figure which is the target of the designated surface selection, and 18 is a sample point which is the coordinate position of the trajectory of the cursor. FIG. 4B is a diagram showing a closed figure projected onto the virtual plane at the coordinate position of the trajectory of the cursor of the present invention. Here, 8 is a three-dimensional figure which is the target of the designated surface selection, 16 is a virtual plane, and 18 is a sample point which is the coordinate position of the trajectory of the cursor. First, as shown in FIGS. 3 (a), 3 (b), 4 (a), and 4 (b), the coordinate position of the cursor moved on the designated surface is sequentially detected, and sample points are sampled. It is acquired as 18 by the control unit 15 (S301). Next, the data of the target three-dimensional figure 8 stored in the storage unit 4 is acquired by the control unit 15 (S302). Next, the three-dimensional figure 8 to be calculated
Plane is set (S303). Next, it is determined whether the calculation is completed (S304). If NO, the coordinate conversion means 13 projects the calculation target surface onto the virtual plane 16 (S305). Next, the inclusion relation determining unit 14 calculates the inclusion rate of the calculation target surface projected on the virtual plane 16 of the sample points 18 (S306). Next, the coverage data is written in the control unit 15 (S307). Next, after setting the next surface as the calculation target surface (S308), S304 is executed. If S304 is YES, the designated surface is prioritized from the surface having the largest coverage data (S30).
9) End later.

As described above, according to the present embodiment, the cursor position detecting means 12 sequentially detects the coordinate position of the cursor as the cursor, which is the coordinate designating section 3, moves, and the coordinate converting means 13 detects points in the three-dimensional space. The element is projected onto an arbitrary two-dimensional space, and the inclusion relation judging means 14 judges whether a certain point on the two-dimensional plane is inside or outside a closed two-dimensional figure on the same plane. The specified surface can be selected simply by moving the cursor on the surface to be specified.

(Embodiment 2) FIG. 5 is a functional block diagram showing the configuration of a graphic processing apparatus according to the second embodiment of the present invention.

In FIG. 5, 1 is an input unit, 2 is a display unit,
Reference numeral 3 is a coordinate designation unit, 4 is a storage unit, and 5 is a data acquisition means. These are the same as in the conventional example, and the same reference numerals are given and the description thereof is omitted.

Reference numeral 12 is a cursor position detecting means for sequentially detecting the coordinate position of the cursor as the cursor is the coordinate designating portion 3, and 13 is a coordinate converting means for projecting points or elements in the three-dimensional space onto an arbitrary two-dimensional space. Reference numeral 19 is a closed figure generation means for generating an enclosed closed figure of the sample points 18 detected by the cursor position detection means 12, and 20 is a closed figure generation means 19
An overlapping area detecting means for detecting an overlapping area of the inclusion closed figure generated by the above and the projection surface of the surface of the three-dimensional figure 8 onto the virtual plane 16, and 21 is a control section for controlling the entire apparatus.

A graphic processing method of the graphic processing apparatus configured as described above will be described below with reference to the drawings.
FIG. 6 is a flow chart showing the determination of the designated surface of the graphic processing apparatus in the second embodiment of the present invention. FIG. 7A is a diagram showing an inclusion closed figure of sample points according to the present invention. Here, 8 is a three-dimensional figure which is the target of the designated surface selection, 22
Is an enclosed closed figure of the sample point 18. FIG. 7B is a diagram showing a projected closed figure of the inclusion closed figure of the sample points on the virtual plane. Here, 8 is a three-dimensional figure which is the target of the designated surface selection, 16 is a virtual plane, and 22 is an enclosed closed figure of the sample points 18 projected on the virtual plane 16.

First, the coordinate position of the cursor moved on the designated surface is sequentially detected, and the control unit 2 sets it as a sample point 18.
1 is acquired (S401). Next, as shown in FIG. 7A, the closed figure generating means 19 creates the inclusion closed figure 22 of the sample point 18 (S402). Next, the data of the target three-dimensional figure 8 stored in the storage unit 4 is acquired by the control unit 21 (S403). Next, the surface of the three-dimensional figure 8 to be calculated is set (S404). next,
It is determined whether the calculation is completed (S405). NO
If so, the coordinate conversion means 13 projects the calculation target surface onto the virtual plane 16 (S406). Next, the overlapping area detecting means 20 calculates the overlapping area between the inclusion closed figure 22 and the calculation target surface projected on the virtual plane 16 (S407). Next, the overlapping area ratio is written in the control unit 21 (S408).
Next, S405 is executed after the next surface is set as the calculation target surface (S409). When S405 is YES, the priority is given to the surface specified by the surface having a large overlapping area ratio (S410), and the process is ended.

As described above, according to the present embodiment, the cursor position detecting means 12 successively detects the coordinate position of the cursor as the cursor, which is the coordinate designating section 3, moves, and the coordinate converting means 13 detects points in the three-dimensional space. The element is projected onto an arbitrary two-dimensional space, the closed figure generation means 19 generates the inclusion closed figure 22 of the sample point 18 detected by the cursor position detection means 12, and the overlapping area detection means 20 is caused by the closed figure generation means 19. Since the overlapping area of the generated enclosed closed figure 22 and the plane of the plane of the three-dimensional figure 8 projected onto the virtual plane 16 is detected, the designated plane can be selected only by moving the designated plane with the cursor. You can

(Third Embodiment) FIG. 8 is a functional block diagram showing the configuration of a graphic processing apparatus according to the third embodiment of the present invention.

In FIG. 8, 1 is an input section, 2 is a display section,
Reference numeral 3 is a coordinate designation unit, 4 is a storage unit, and 5 is a data acquisition means. These are the same as in the conventional example, and the same reference numerals are given and the description thereof is omitted.

Reference numeral 12 is a cursor position detecting means for sequentially detecting the coordinate position of the cursor as the cursor is the coordinate designating portion 3, and 13 is a coordinate converting means for projecting points or elements in the three-dimensional space onto an arbitrary two-dimensional space. 23 is a center of gravity detecting means for detecting the center of gravity of the surface of the three-dimensional figure 8, and 24 is a sample point 18
Point-to-point distance calculation means for calculating the sum of the distances in the virtual plane 16 between the center of gravity detected by the center of gravity detection means 23 and
Is a control unit that controls the entire apparatus.

A graphic processing method of the graphic processing apparatus configured as described above will be described below with reference to the drawings.
FIG. 9 is a flow chart showing the determination of the designated surface of the graphic processing apparatus in the third embodiment of the present invention.

First, the coordinate position of the cursor moved on the designated surface is sequentially detected, and the control unit 2 sets it as a sample point 18.
5 is acquired (S501). Next, the data of the target three-dimensional figure 8 stored in the storage unit 4 is stored in the control unit 25.
To obtain (S502). Next, the surface of the three-dimensional figure 8 to be calculated is set (S503). Next, it is determined whether the calculation is completed (S504). If NO, the center of gravity of the calculation target surface is calculated by the center of gravity detecting means 23 (S505). Next, the coordinate conversion means 13 projects the center of gravity of the calculation target surface onto the virtual plane 16 (S506). Next, the point-to-point distance calculating means 24 calculates the sum of the distances between the sample points 18 and the barycentric projection points on the virtual plane 16 (S5).
07). Next, the sum total data of the distances is written in the control unit 25 (S508). Next, after the next surface is set as the calculation target surface (S509), S504 is executed. S504 is Y
In the case of ES, the priority is given to the surface specified by the surface having the smallest total distance data (S510), and the process is ended.

As described above, according to the present embodiment, the cursor position detecting means 12 successively detects the coordinate position of the cursor as the cursor which is the coordinate designating section 3 moves, and the coordinate converting means 13 detects the point in the three-dimensional space. The element is projected onto an arbitrary two-dimensional space, the center of gravity detection means 23 detects the center of gravity of the surface of the three-dimensional figure 8, and the point-to-point distance calculation means 24 detects the sample point 18 and the center of gravity detected by the center of gravity detection means 23. Since the sum total of the distances on the virtual plane 16 is calculated, the designated surface can be selected by simply moving the designated surface with the cursor.

[0039]

As described above, according to the present invention, the designated surface can be selected only by moving the designated surface with the cursor, so that the number of operations for editing the three-dimensional figure can be reduced. Work efficiency can be significantly improved. Further, since the designated surface is directly designated, it is possible to realize an excellent graphic processing method and graphic processing apparatus that allow an operator to intuitively understand the designated surface.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing a configuration of a graphic processing device according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing determination of a designated surface of the graphic processing device according to the first embodiment of the present invention.

FIG. 3A is a diagram showing a state where a designated surface of the present invention is designated with a cursor. FIG. 3B is a diagram showing a projection closed figure of a three-dimensional figure where the designated surface of the present invention is designated with a cursor on a virtual plane.

4A is a diagram showing coordinate positions on a trajectory of a cursor of the present invention; FIG. 4B is a diagram showing a projected closed figure of a coordinate position of a trajectory of a cursor of the present invention on a virtual plane.

FIG. 5 is a functional block diagram showing the configuration of a graphic processing device according to a second embodiment of the present invention.

FIG. 6 is a flowchart showing determination of a designated surface of the graphic processing apparatus according to the second embodiment of the present invention.

FIG. 7 (a) is a diagram showing an enclosed closed figure of sample points of the present invention. (B) is a diagram showing a projected closed figure of an enclosed closed figure of sample points of the present invention on a virtual plane.

FIG. 8 is a functional block diagram showing the configuration of a graphic processing device according to a third embodiment of the present invention.

FIG. 9 is a flowchart showing determination of a designated surface of the graphic processing apparatus according to the third embodiment of the present invention.

FIG. 10 is a functional block diagram showing the configuration of a conventional graphic processing device.

FIG. 11 is a flowchart showing determination of a designated surface of a conventional graphic processing apparatus.

FIG. 12 is a flowchart showing determination of a designated surface of a conventional graphic processing device.

FIG. 13 is a flowchart showing determination of a designated surface of a conventional graphic processing apparatus.

FIG. 14 (a) is a diagram showing points selected to determine a designated surface. (B) is a diagram showing ridge lines selected to determine a designated surface. (C) shows ridge lines selected to determine a designated surface. Figure

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Input part 2 Display part 3 Coordinate designation part 4 Storage part 5 Data acquisition means 6 Designated surface determination means 7 Control part 8 Three-dimensional figure 9 Points 10 Ridge line 11 Ridge line 12 Cursor position detection means 13 Coordinate conversion means 14 Inclusive relation judgment means 15 Control unit 16 Virtual plane 17 Cursor locus 18 Sample points 19 Closed figure generation means 20 Overlapping area detection means 21 Control section 22 Enclosed closed figure 23 Center of gravity detection means 24 Point distance calculation means 25 Control section

Claims (6)

[Claims] 1. A cursor position detecting step of sequentially detecting a coordinate position of a cursor to be moved on a surface of a three-dimensional figure to be designated, and a coordinate plane detected in the cursor position detecting step is a virtual plane of a surface of the three-dimensional figure. And a designated surface determination step of determining the surface having the largest coverage detected by the coverage rate detection step as a designated surface. Figure processing method. 2. A cursor position detecting step of sequentially detecting a coordinate position of a cursor to be moved on the surface of a three-dimensional figure to be designated, and a closed figure forming a closed figure inscribed at the coordinate position detected by the cursor position detecting step. A figure creating step, an overlapping area rate detecting step of detecting an area rate in which the closed figure created in the closed figure creating step overlaps a projected closed figure onto a virtual plane of a three-dimensional surface, and the overlapping area rate detection A designated surface determining step of determining a surface having the largest area ratio detected by the step as a designated surface. 3. A cursor position detecting step of sequentially detecting coordinate positions of a cursor to be moved on a surface of a three-dimensional figure to be designated, a center of gravity detecting step of calculating a center of gravity of each surface of the three-dimensional figure, and a virtual plane. An inter-point distance calculation step of calculating a sum of distances between the coordinate position detected by the cursor position detection step on the projection plane and the center of gravity detected by the center of gravity detection step, and a distance calculated by the inter-point distance calculation step And a designated surface determining step of determining a surface having the smallest sum of the designated surfaces as a designated surface. 4. A cursor position detecting means for sequentially detecting coordinate positions of a cursor to be moved on the surface of a three-dimensional figure to be designated, and a coordinate plane detected by the cursor position detecting means is a virtual plane of the surface of the three-dimensional figure. And a designated surface determination means for determining the surface having the largest coverage detected by the coverage detection means as the designated surface. Figure processing device. 5. A cursor position detecting means for sequentially detecting coordinate positions of a cursor to be moved on the surface of a three-dimensional figure to be designated, and a closed figure for creating a closed figure inscribed at the coordinate position detected by the cursor position detecting means. Figure creating means, overlapping area rate detecting means for detecting an area rate in which the closed figure created by the closed figure creating means overlaps a projected closed figure on a virtual plane of a three-dimensional surface, and the overlapping area rate detection A graphic processing apparatus comprising: a designated surface determining means for determining a surface having the largest area ratio detected by the means as a designated surface. 6. A cursor position detecting means for sequentially detecting a coordinate position of a cursor moving on a surface of a three-dimensional figure to be designated, a center of gravity detecting means for calculating a center of gravity of each surface of the three-dimensional figure, and a virtual plane. Point-to-point distance calculation means for calculating the sum of distances between the coordinate position detected by the cursor position detection means on the projection plane and the center of gravity detected by the center-of-gravity detection means, and the distance calculated by the point-to-point distance calculation means And a designated surface determining means for determining the surface having the smallest sum of the designated surfaces as the designated surface.