JP3383710B2 - 3D CAD system - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional CAD system for designing an object while displaying it three-dimensionally, and more particularly to a three-dimensional CAD system which enables efficient use of the system.

Three-dimensional CAD systems are used in various fields.
It is being used for three-dimensional design, and the construction of a structure that can realize more efficient use is being called for. For example, three-dimensional CA
As one usage form of the D system, there is a route determination of a cable in an electric device and a route determination of a pipe in a plant facility. Such route determination is designed even by using a three-dimensional CAD system. It will be hard work. Against this background, a new three-dimensional CAD
There is a call for system construction.

[0003]

2. Description of the Related Art A control unit, an operation panel and the like are provided with a large number of bundled wires and cables. Until now, routes for these connecting wiring materials have been manually determined. That is, the designer manually determines the route of the connecting wiring material while maintaining the necessary extra length while searching for the optimal route by assuming a pseudo three-dimensional space from the drawing at the stage of mounting and designing the device. I was doing it. At this time, the connecting wiring materials may overlap with each other in a double route depending on the route, and in such a case, the diameters of these connecting wiring materials rarely become constant.

From now on, if the route of the connecting wiring material is manually determined as in the past, even if the individual examination can be made, finally the connecting wiring material is wired in a three-dimensional shape. Then, the maximum outer diameter of the connecting wiring material swells more than expected at the overlapping portion of the connecting wiring material, which often causes a problem in mounting.

In order to solve such a problem, recently, a three-dimensional CAD system is used to prepare the same environment as the actual product assembly, in which the route of each connecting wiring material is determined. By arranging these connecting wiring materials in the same form as the actual products, we have come to adopt a method of reconsidering if a defect is found. If this method is adopted, problems will be discovered at the stage of actually assembling the product, and it will be possible to avoid the problem of the manual method that wastes time and money due to a drastic design change. .

In the three-dimensional CAD system, two modes, a sketch mode and an extrusion mode, are prepared.
First, in sketch mode, display the work surface specified by the user so that its normal line is perpendicular to the display screen, and let the user create an additional part on the work surface using the cursor. Then, The configuration is such that an object is designed by entering the push-out mode and allowing the user to key in the amount of protrusion of the added portion. That is, the actual design is performed on a two-dimensional work surface.

At the time of adopting such a structure, the conventional three-dimensional CAD system does not adopt the structure of giving the three-dimensional coordinate position to the cursor displayed on the display screen. Therefore, it is only on the work surface where the normal line is orthogonal to the display screen that the cursor position displays the accurate coordinate position.

Therefore, in the conventional three-dimensional CAD system, when the processed object is displayed in an arbitrary direction, the user can input the coordinate value of the object by key input regardless of the cursor. A configuration is adopted in which the processing pointed by the user is executed using the point indicated by the coordinate values as the working point.

[0009]

However, according to such a conventional technique, there is a problem that an efficient design cannot be realized because the work points have to be keyed in one by one. there were.

For example, in the case of determining the route of the connecting wiring material, there is a problem that it takes time to determine the route because the refraction point of the connecting wiring material has to be entered by key input. It was

Since the conventional three-dimensional CAD system does not adopt a configuration of giving a three-dimensional coordinate position to the cursor, the cursor has only a meaning as a point, which is why the cursor does not appear. There was a problem that we could not obtain any information necessary for the work.

For example, in the case of route determination of connecting wiring materials, it is necessary to obtain any information necessary for route determination such as how far the cursor position is from a nearby object plane. There was a problem that I could not do it.

From the above, the conventional three-dimensional CAD
I was using the system, while looking at the object in three dimensions,
There is a problem that it is not possible to determine the route of the connecting wiring material while verifying the degree of swelling due to the overlap.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a new three-dimensional CAD system that enables efficient use of the system.

[0015]

FIG. 1 shows the principle configuration of a three-dimensional CAD system equipped with the present invention. 1 in the figure
Is a main body device, which is designed while stereoscopically displaying an object according to a set three-dimensional coordinate axis, 2 is a terminal included in the main body device 1, and has a display screen and functions as an interactive device with a user An input device 3 of the terminal 2 is provided with, for example, three buttons 4, and is used to specify a cursor position on a display screen by freely moving on a plane.

The main unit 1 includes an input / output control unit 10 and
The object information storage unit 11, the object display unit 12, the cursor display unit 13, the correspondence table unit 14, the switching unit 15, the specifying unit 16, the interference frame display unit 17, and the measuring unit 18 are provided.

The input / output control unit 10 controls input / output processing with the terminal 2. The object information storage unit 11 manages shape information of designed objects. The object display unit 12 uses the data stored in the object information storage unit 11 to stereoscopically display the object to be processed on the display screen according to the set three-dimensional coordinate axes. The cursor display unit 13 displays a cursor at the position indicated by the input device 3.

The correspondence table 14, for example, associating one to x Direction three buttons 4 with the input device 3, the association of one another in the y Direction, z direction remaining one corresponding <br/> with Rutotomoni in, for example, buttons associated with the x-direction
Button 4 and button 4 associated with the y direction are operated simultaneously
When it is done, the xy direction is associated and the x direction is associated.
Button 4 and the button 4 associated with the z direction are the same.
When operated, it corresponds to the xz direction and corresponds to the y direction.
Button 4 to be associated with and button to be associated with the z direction
When 4 and 4 are operated at the same time,
Also, when the three buttons 4 are operated simultaneously, the xyz direction
As referred to associate the direction, manages the operation state of the three <br/> buttons 4 with the input device 3, the correspondence between the direction represented by three-dimensional coordinate axes. The switching unit 15 switches the input mode of the button 4 of the input device 3 from the normal mode to the three-dimensional movement direction instruction mode. The identifying unit 16 refers to the management data of the correspondence table unit 14 to determine the moving direction of the cursor movement and identify the cursor position. The interference frame display unit 17 displays an interference frame having an axis in the direction of the set three-dimensional coordinate axis in association with the cursor. Measuring unit 1
8 measures and displays the distance between the cursor and an object located in the vicinity thereof.

[0019]

In the present invention, when the object display section 12 stereoscopically displays the object to be processed according to the set three-dimensional coordinate axes, the switching section 15 inputs the input data by monitoring the user's key operation, for example. When it is detected that there is a mode change instruction, the input mode of the button 4 of the input device 3 is switched from the normal mode to the three-dimensional movement direction instruction mode.

The input mode of the button 4 is the three-dimensional movement direction finger.
When switched to the display mode, the identifying unit 16 causes the input device to
Operation of button 4 for the direction of cursor movement specified by 3
Determine the cursor position by determining according to the coordinate axis indicated by the state
To do. For example, according to the management data of the correspondence table unit 14,
Ix directionButton 4 associated with the direction is operated
When detecting andx directionMoved to
It is judged as a thing and the cursor position after movement is specified,
y directionCheck that the button 4 associated with the
When you go out, the cursory directionThat was moved to
To determine the cursor position after movement,z directionDirection
Detects that button 4 associated with is operated
Sometimes the cursorIs zDetermined to have been moved in the direction
The cursor position after the disconnection and the movement is specified.That
For example, the button 4 and the y direction that are associated with the x direction
Button 4 associated with the direction is operated at the same time
Is detected, the cursor was moved in the xy direction.
It is judged as a thing and the cursor position after movement is specified,
The button 4 associated with the x direction and the button 4 associated with the z direction are
When it is detected that button 4 and
, It is determined that the cursor has been moved in the xz direction.
To specify the cursor position after movement and associate it with the y direction
And a button 4 associated with the z direction.
Cursors are detected when
Is determined to have been moved in the yz direction, and the
-Sol position is specified. And, for example, x
Button 4 associated with the direction and associated with the y direction
Button 4 and button 4 associated with the z direction are simultaneously
When it is detected that the
Direction of cursor movement in xyz direction set to rate
To determine the cursor position after the move
Of.

According to this processing, for example, as shown in FIG. 2, when the cursor moves from the point A to the point B on the display screen and the button 4 associated with the xy directions is operated, As indicated by the broken line of the X mark in the figure, it is determined that the cursor has moved "x ₁ " in the x-axis direction and "y ₂ " in the y-axis direction, and the cursor position after the move is specified. , Yz directions are operated, the cursor is moved in the y-axis direction by "y" as indicated by the broken line of the circle in the figure.
₁ ", in the z-axis direction" cursor position after the movement is determined to have moved z ₁ "is specified, when the button 4 associated with the xz direction is operated," dashed with the △ mark "in FIG. represented as in, "x _2" cursor in the x-axis direction, the z-axis direction "z _2" is determined to have moved the cursor position after the movement is to be identified.

In this way, according to the present invention, no matter which direction the three-dimensional coordinate axes of the object to be stereoscopically displayed face,
Since it becomes possible to specify an arbitrary point in the three-dimensional space with the cursor, it is possible to significantly improve the utilization efficiency of the three-dimensional CAD system.

[0023]

[0024]

[0025]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to an embodiment applied to route determination of a connecting wiring material in an electric device.

In the electric device, as shown in FIG. 3, the units of the device are connected to each other by using bundled wires or cables. Specifically, such bundled lines are three-dimensionally mounted as shown in FIG. That is, as shown in FIG. 5, those that pass through the same route are bundled and bent at a plurality of bending points to connect the units. 6 to 8 show a two-dimensional model of the wiring form of FIG.

In this wiring form, when bundles or the like are bundled by passing through the same route, as shown in FIG. 9, the cumulative area naturally increases at that portion. Here, FIG. 9A shows an example of a round cable, and FIG. 9B shows an example of a flat cable.

Due to such overlapping of bundles and cables (hereinafter referred to as bundles), there is a problem that the route of the bundles cannot be easily determined if the conventional three-dimensional CAD system is used. It was That is, as described above, in the conventional three-dimensional CAD system, the cursor position displays the accurate coordinate position only on the plane where the display screen and the normal line are orthogonal to each other. The cursor only has a meaning as a dot. From this, in the conventional three-dimensional CAD system, it is not possible to determine the route of the bundle line while observing the object three-dimensionally and verifying the degree of bulging due to the overlap.

In order to solve such a problem, the present invention employs a three-dimensional CAD system in which an accurate three-dimensional coordinate position is given to a cursor displayed on a display screen. That is, when there is an object that is stereoscopically displayed as shown in FIG.
When the cursor is positioned at the lower left corner of the P2 plane which is the front surface of the object as shown in (b), the cursor is moved to an arbitrary position in the three-dimensional space, for example, as shown in FIG. It realizes a configuration that enables the user to move to a specified position on the internal P3 plane.

Further, according to the present invention, the axis is set in the direction of the three-dimensional coordinate axis (set by the user's key operation) corresponding to the configuration of giving the accurate three-dimensional coordinate position to the cursor. By defining an interference piece as shown in FIG. 11 and displaying the interference piece in association with the cursor, a configuration is made that enables grasping the distance relationship between the cursor and an object in the vicinity thereof. That is, as shown in FIG. 12, by displaying an interference frame having a three-dimensional axis line in the direction of the set three-dimensional coordinate axis in association with the cursor,
This makes it possible to understand the distance relationship between the cursor and its nearby objects.

At this time, when there is an object that interferes with the three-dimensional axis, it is possible to adopt a configuration in which the three-dimensional axis ahead of the point of interference is not displayed, as shown in FIG. It is also possible to adopt a configuration in which the origin of the interference frame where the cursor is located and the distance to the interference point are measured and displayed on the display screen. Also,
At this time, when the three-dimensional axis line is hidden by the object, as shown in FIG. 14, the hidden portion (broken line portion in the figure) is displayed in a different color, or the like. It is also possible to collect. In addition, the distance display to the interference point is prepared to inform the user whether or not it is possible to wire the bundle of wires, and the distance can be calculated while considering the diameter of the bundle of wires that has been wired up to that point. By performing the measurement, if the measured distance cannot realize the preset gap, processing such as issuing a warning is performed.

FIG. 15 shows a system configuration of a three-dimensional CAD system of the present invention which realizes such a configuration.
In the figure, 20 is a CPU, 21 is a main memory, 22 is an auxiliary storage device, 23 is a display, 24 is a keyboard, 25 is a mouse, 26 is an external interface, 27 is a bus line, 2
Reference numeral 8 is a three-dimensional CAD basic function unit, and 29 is a three-dimensional CAD application function unit.

This mouse 25 corresponds to the input device 3 shown in FIG. 1 and has three buttons A, B and C as shown in FIG. 16, and these buttons A, B and C are provided.
, When it is set to the normal input mode, ing to exert button functions of conventional three-dimensional CAD system. Before going into the detailed description of the present invention, the present invention will be described.
To facilitate the solution, the three dimensions associated with the present invention
The processing of the CAD system will be described. In this invention
In the related three-dimensional CAD system, when the three- dimensional movement direction instruction mode is set, as shown in FIG. 17, the button A outputs that the movement direction of the cursor is the xy direction when operated by the user. Then, the button B outputs that the movement direction of the cursor is the xz direction when operated by the user, and the button C outputs that the movement direction of the cursor is the yz direction when operated by the user. To function.

The three-dimensional CAD basic function unit 28 is the same as the conventional three-dimensional CAD.
The processing for creating a three-dimensional model of the three-dimensional CAD system is executed. On the other hand, the three-dimensional CAD application function unit 29 is prepared to implement the present invention, and includes a cursor function switching unit 30, a cursor signal control unit 31, and a cursor display position control unit 32. , Interference frame generation control unit 33, distance detection unit 34, cursor coordinate value detection unit 35, cursor movement start origin setting unit 36, fixed point generation unit 37, orbit line generation unit 38, hidden line display control It includes a section 39 and a hidden line display color control section 40.

The cursor function switching unit 30 switches the input mode of the button of the mouse 25 from the normal mode to the three-dimensional movement direction instruction mode in response to a specific key operation of the keyboard 24. The cursor signal control unit 31 controls the cursor signal. The cursor display position control unit 32 controls the display position of the cursor. Interference frame generation control unit 33
Generates an interference frame and displays it at the cursor position. As shown in FIG. 18, the distance detecting unit 34 determines the distance from the absolute coordinate origin of the cursor, the distance from the relative coordinate origin, and the distance (x / y /
z distance) and are displayed on the display screen.

The cursor coordinate value detection unit 35 detects the coordinate value of the cursor by measuring the moving distance of the cursor. The cursor movement start origin setting unit 36 responds to a specific key operation of the keyboard 24 (it can also be implemented by operating the button of the mouse 25), so that the position of the displayed cursor becomes the movement start origin of the cursor. Set as the coordinate origin. The fixed point generation unit 37 responds to a specific key operation of the keyboard 24 (which can also be implemented by a button operation of the mouse 25), and determines the position of the displayed cursor as a fixed point that is a bending point of the bundle line. To generate. The trajectory line generation unit 38 generates a trajectory line that connects the set fixed points. The hidden line portion display control unit 39 controls the display of the three-dimensional axis portion of the interference frame hidden by the object. The hidden line display color control unit 40 changes the display color of the three-dimensional axis line portion of the interference frame hidden by the object.

FIG. 19 shows a three- dimensional CAD related to the present invention .
An example of the process flow which a system performs is shown in figure. Then, according to the processing flow will be described in detail the route determination process of wire bundles in an electrical device that runs using three-dimensional CAD system associated with the present onset bright.

The three-dimensional CAD system associated with the present onset Ming, enters the three-dimensional modeling of the electrical device, as shown in the process flow of FIG. 19, first, in step 1, creating a normal three-dimensional model By entering a process and interacting with the user, a three-dimensional model of the electric device is generated.

While continuing this process, in the following step 2,
When it is determined whether or not the user has issued an instruction to switch the input mode of the button of the mouse 25 from the normal mode to the three-dimensional movement direction instruction mode, and when it is determined that the instruction has not been issued, the process returns to step 1 and is continued. Generate a three-dimensional model of an electric device. On the other hand, if it is determined that it has been issued, go to step 3
The input mode of the button of 5 is switched to the three-dimensional movement direction instruction mode, and the display of the interference frame is started. That is, it is set such that the button operation of the mouse 25 enters the three-dimensional movement direction instruction mode in which the movement direction of the cursor is instructed, and the interference frame is displayed in association with the cursor. Then, in step 4, in response to the key operation of the relative coordinate origin setting operated by the user,
Set the position of the displayed cursor as the relative coordinate origin.

Following this, the user operates the mouse 25 to move the cursor to a point that becomes the inflection point of the bundled line. In the following step 5, the cursor 25 is moved by the mouse and the mouse is moved. When it is determined that the button has been operated after waiting for 25 button operations, the process proceeds to step 6 to determine which of the buttons A, B, and C has been operated to determine the moving direction of the cursor. Then, while moving the cursor to the move destination,
Interference pieces also move in line with this. That is, when it is determined that the button A is operated, it is determined that the moving direction of the cursor is the xy direction, and when it is determined that the button B is operated, it is determined that the moving direction of the cursor is the xz direction. Then, when it is determined that the button C has been operated, it is determined that the moving direction of the cursor is the yz direction.

Then, in step 7, according to the moving direction determined in step 6, the distance between the current position of the cursor and the relative coordinate origin set in step 4 is measured, and the measured distance is displayed on the display screen. In addition, the distance between the current position of the cursor and the origin of the absolute coordinates of the cursor is measured, and the measured distance is displayed on the display screen. That is, when the moving direction of the cursor is determined, as shown in FIG. 2, the direction of the three-dimensional coordinate axis set at that time, the cursor position on the display screen before the movement, and the display screen after the movement. It is possible to specify the amount of movement of the cursor in each 3D coordinate axis direction from the above cursor position. Use this to measure the distance between the relative coordinate origin and the absolute coordinate origin, and display it on the display screen. It will be displayed.

Subsequently, in step 8, while referring to the three-dimensional model of the electric device generated in step 1, an object interfering with the three-dimensional axis of the interfering frame is obtained, and between the interfering point and the interfering frame. The measurement of the distance is started and the measured distance is displayed on the display screen. The distance to the interference object displayed at this time (as described above, when another bundle line is already arranged, the gap distance in consideration of it is displayed) and the diameter of the arrangement target bundle line, the user Determines whether or not the bunch line to be placed can be placed at the moved cursor position, and when determining that the bunch line can be placed, requests the setting of a fixed point, which is the inflection point of the bunch line, according to the key operation. Therefore, in the subsequent step 9, it is determined whether or not the instruction to set the inflection point is issued.

When it is determined in step 9 that the instruction to set the refraction point is not issued, the process returns to step 5. That is, since the user moves the cursor to another point, the process returns to step 5 to specify the cursor position. On the other hand, when it is determined that the instruction to set the inflection point is issued, the process proceeds to step 10, where the inflection point is generated and displayed, and the solid of the bunch line is generated between the inflection point generated previously. Display on the display screen. Then, in the following step 11, it is determined whether or not an instruction to switch the input mode of the button of the mouse 25 from the normal mode to the three-dimensional movement direction instruction mode is issued by the user, and when it is determined that the instruction is not issued, Returning to step 5, the bundle route determination process is continued as it is. When it is determined that the bundle has been issued, the process returns to step 1 to generate a three-dimensional model of the electric device.

[0044] Thus, by using the three-dimensional CAD system associated with the present onset bright, the user, as you can move the cursor anywhere in the three-dimensional space the cursor by moving on the display screen In addition, since the distance between the cursor and the object located near it can be grasped numerically, the bulge due to the overlapping of the bundle lines can be evaluated, and the bundle lines in the electric device can be easily operated according to the simple operation. You will be able to determine the route.

The three-dimensional CAD system related to the present invention described above.
On the stem, the cursor movement direction is xy direction, x
z-direction, it has been define three of yz direction, the direction of movement of the cursor, in addition, as shown in FIG. 20, x-direction, y-direction, z-direction, xyz direction there Ru. Third order of the present invention
The original CAD system, a mouse the whole direction of movement of these 25
It realizes to be able to input with the button of
is there. In order to realize this, the three-dimensional CA of the present invention is used.
In the D system, as shown in FIG. 21, buttons A, B,
Correspondences between the operation of C and these moving directions will be assigned. That is, button A is
The cursor moves in the x direction when
When the user operates the button B, the cursor is output.
Output that the moving direction of the cursor is the y direction, and button C
When operated by the user, the moving direction of the cursor is z direction
Function to output that. And button A
When button and button B are operated simultaneously by the user,
Output that the moving direction of the sol is the xy direction, and press button A.
When button and button C are operated simultaneously by the user,
Output that the moving direction of the sol is the xz direction, and press button B.
When button and button C are operated simultaneously by the user,
A device that outputs that the moving direction of the sol is the yz direction
To work. And button A, button B, and button C are
When operated simultaneously by the user, the moving direction of the cursor changes
It functions to output that it is in the xyz direction. However,
Xyz direction of this is a three-dimensional motion, since only a two-dimensional motion on the display screen can not determine the amount of movement of the cursor, when it is set in the moving mode of the xyz direction, for example, , Between the x-direction movement amount, the y-direction movement amount, and the z-direction movement amount, "x:
The configuration is such that the amount of movement of the cursor is determined by imposing a constraint condition such that the relationship of “y: z = 2: 3: 5” is defined. According to this configuration, the present invention
By using the 3D CAD system of
Cursor on the display screen by moving the cursor
If you can move to any position in the three-dimensional space
The distance between the cursor and an object located near it
Since it becomes possible to grasp numerically,
While assessing the bulge due to
You will be able to determine the route of the bundle of wires in the device.

The present invention will be described in detail with reference to the illustrated embodiments.
However, the present invention is not limited to this. example
If, in the real施例, the present invention has been disclosed in accordance with an example of application to route determination process of wire bundles in an electrical apparatus, the present invention is not intended limited to such applications.

[0047]

As described above, according to the present invention,
Even 3-dimensional coordinate axes of the object to be three-dimensional display is not facing any direction, increasing from the benzalkonium such as may be set to any point in 3D space with the cursor, greatly efficiency of the three-dimensional CAD system Will be able to.

[Brief description of drawings]

FIG. 1 is a principle configuration diagram of the present invention.

FIG. 2 is an explanatory diagram of processing of the present invention.

FIG. 3 is an example of a wiring system of an electric device.

FIG. 4 is an explanatory diagram of a wiring form.

FIG. 5 is an explanatory diagram of a wiring form.

FIG. 6 is an explanatory diagram of a two-dimensional model of a wiring form.

FIG. 7 is an explanatory diagram of a two-dimensional model of a wiring form.

FIG. 8 is an explanatory diagram of a two-dimensional model of a wiring form.

FIG. 9 is an explanatory diagram when wirings overlap.

FIG. 10 is an explanatory diagram of processing of the present invention.

FIG. 11 is an explanatory diagram of an interference frame.

FIG. 12 is an explanatory diagram of display processing of a three-dimensional axis line of an interference frame.

FIG. 13 is an explanatory diagram of a display process of a three-dimensional axis line of an interference frame.

FIG. 14 is an explanatory diagram of a display process of a three-dimensional axis line of an interference frame.

FIG. 15 is a system configuration diagram of a three-dimensional CAD system of the present invention.

FIG. 16 is an explanatory diagram of a mouse button configuration.

FIG. 17 is used in a CAD system related to the present invention .
Illustration of correspondence between the mouse button and the cursor movement direction
It is.

FIG. 18 is an explanatory diagram of a displayed distance.

FIG. 19 is a processing flow executed by the CAD system related to the present invention .

FIG. 20 is an explanatory diagram of a moving direction of a cursor.

[Figure 21] Ah <br/> Ru In one embodiment of correspondence between the mouse button and the cursor movement direction to be used in the CAD system of the present invention.

[Explanation of symbols]

1 Main unit 2 terminals 3 input devices 4 buttons 10 I / O controller 11 Object information storage 12 Object display 13 Cursor display 14 Compatible table section 15 Switching unit 16 specific section 17 Interference frame display section 18 Measuring section

Continuation of the front page (56) Reference JP-A-4-182721 (JP, A) JP-A-62-209481 (JP, A) JP-A-6-223154 (JP, A) JP-A-4-335418 (JP , A) JP-A-6-44358 (JP, A) JP-A-62-80694 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G06F 3/00 658 G06F 17/50 G09G 5/08

Claims (2)

(57) [Claims] 1. A three-dimensional CAD system in which a cursor is displayed at a position pointed by an input device that specifies a cursor position by freely moving on a plane, and an object is designed to be stereoscopically displayed according to a set three-dimensional coordinate axis. , The three buttons of the input device are associated with the x, y, z directions of the three-dimensional coordinate axes, and when the three-dimensional movement direction instruction mode is set, the three buttons of the three buttons are Depending on the operating state of one of the buttons, it is determined whether the instruction is a cursor movement instruction in the x direction, a cursor movement instruction in the y direction, or a cursor movement instruction in the z direction, and the above three Within the button
Depending on the operation state of the two buttons, it is determined whether the cursor movement instruction is in the xy direction, the cursor movement instruction in the xz direction, or the cursor movement instruction in the yz direction . The three-dimensional CAD system according to claim 3, further comprising a specifying unit that specifies a cursor position indicated by the input device. 2. The three-dimensional CAD system according to claim 1, wherein the specifying unit moves the cursor in the xyz direction set to a specified moving amount ratio when all of the three buttons are in an operating state. A three-dimensional CAD system characterized by determining that it is a direction instruction and specifying the cursor position pointed by the input device according to the result of the determination.