JPS61262884A - Method for drawing to specified point on element - Google Patents

Abstract

PURPOSE:To simplify drawing of CAD (Computer Aided Design) by finding a contact near a circle element designated point automatically after inputting point coordinate and creating a tangential line to the point coordinate or finding an end point near a segment element designated point automatically and creating a straight line connecting them. CONSTITUTION:When drawing a tangential line to a circle, a point P2 is hit after inputting command 'LINE', and then the circle C is hit. As there are two tangential lines to the circle C, a point P1 on the circumference near a point at which a desired tangential line will come into contact with the circle C is made a hit point to the circle C. A desired tangential line L can be drawn in this way. That is, when there is no command before hitting of the circle C, it is interpreted automatically that a command 'find the point of contact' is omitted, and processing is made after supplementing it. When drawing a straight line to the end point, the point P2 is hit after inputting a command 'LINE', and then a segment L1 is hit. Though the segment L1 has two end points, if the point P1 is a desired end point, a straight line L2 that connects the point P2 and desired end point P1 of the segment L1 is drawn.

Description

[Detailed Description of the Invention] [Field of Application in Industry-1-] The present invention is based on CAD (Computer Aided
This invention relates to a method of drawing a line to a specific point on an element in a design system.

[Conventional technology]

The CAD system draws the design 81 diagram etc. using the keyboard 1 while looking at the CR'r display, and the completed design δ
1 is stored in a storage device, and as necessary (reads out and displays or prints the data). An example of this system is shown in FIG. 2. This is ICA D (Integrated Com-
putter Aided Design and ma
This is a block diagram of the overall structure of the manufacturing system, starting from the top: CAD control section, command 1 section 2 graphic processing section cwss.

Graphic display (GD) and character display (CI)
It consists of ID etc.

The CAD control section is the main section of ICAD, and initializes and controls each module.

Specifically, loading the initialization table row 1, row 1 module, and each CAD component (GwSS,:
Initialize and terminate the J cloak section (business), delete the load module, delete the initialization table, register the error "1", terminate the lightning processing, initialize the FORT RAN library, and Sends and receives the saw conversation part Mainp II Dalam. Initialization is the first process to be performed when using the CAD system, and this prepares the minimum operating environment for CAD. This initialization is performed in the CAD 1Iil+ It is executed every time the control section calls the initialization routine, and the usage idea is that you can freely initialize the business by incorporating the initialization contents into the initialization routine.In a standard initialization routine, 84: I Initial value settings for CAD and initial screen settings (when the input model name exists in the parts library or model mask, data is read from them and displayed on the screen. or when it does not exist in the model mask, set the initial screen).Finalization is performed by calling the finalization routine (1) at the end of CAD use, and the standard finalization routine closes the parts library.

The conversation section Coran 1' analysis section performs syntactical interpretation of the command name and modification parameters of the input command. This interpretation was entered by Yuji from the workstation CD, ClID's -1--ball 1'KB or filet 1'B. :1 Manto will be analyzed based on the syntax definitions registered in the 21 Man1 syntax file. If the syntax of the input command 1 is determined to be correct through this analysis, the conversation section command analysis section calls the communication program corresponding to the command. The operation of the conversation part command analysis part is shown in FIG. 3 using LINE command I'. ■, ■ below.

. . . corresponds to ■, ■, . . . attached to the drawing.

First, (1) requests the command name and modification data to the conversation section data operation section 1, and receives them from the conversation section data operation section.

Next, it is determined whether or not ``L I N IE ) J < near mant'' is correct, and the syntax definition is read from the ``resynx'' file and loaded. ■Performs syntax analysis of qualified data, and ■Creates a parameter list.

■CA L the communication department of LINE Command 1
T-L, ■Paratu Tarisu I- is handed over to the communication department of LINE Mi Command. ■L Executes the communication section of INEN Fuco 1.

If there is an error in the entered 3,771 names and qualifying parameters, the conversation section will display a message on the CHD and prompt you to re-enter. The command syntax is defined using command definition macro 11 instructions. Correlation between Command F and the communication program is performed using the processor 7C command.

The graphic data analysis section extracts the graphic parameters of the input command and performs syntactical interpretation. Specifically, the functions of the graphic data operation section are: 1) Outputting prompting characters such as PO8 and ENT, 2) Retrieving input graphic data, 2) Checking the syntax of graphic data, and 2) GROUP in ENT mote.

WIN] and CIIAIN specified processing, ■pos.

These are: re-input processing to enter the ENT mode, ① error message output, ② graphic data analysis unit service routine board, ② interface with the communication unit. FIG. 4 shows the interface.

The conversation section data operation section includes a command input (reception) data processing section, a graphic input (bone fine) data processing section, a data input/output processing section (coordinate transformation, menu conversion), and a terminal input/output section (VTAM interface and CPU interface). )
It is equipped with a computer to manage character displays and tablets. To enumerate, ■Table resolution, ■Interpretation and digitization of graphic data, ■Management of menus, and ■Management of input sources. The command modifier input is temporarily stored in this conversation section data manipulation section, and when a colon is input, the stored input is sent to the conversation section command analysis section. FIG. 5 illustrates this functionality.

The graphic processing unit cwss performs specific point arithmetic search, system control,
Figure creation, editing, screen [Equipped with construction, readout, mask access, display control, entity management, and work file management functions, creates and edits shapes using data input from GD and CHD terminals, and displays the shapes on GD. It also searches for work files and manages graphic data.

GWSS has KST, and V S A M (Vir
tual Storage Access Method
d) A data storage file and part library for permanently storing graphic data are attached via the data management section, and a work file management system is attached via the data management section.

The virtual area that stores the entities handled by the GWSS (Record 1) is called the graphic storage space, and this space is divided into units called classes, sections, and pages. A class is a unit that implements a cwss exterior finishing class. r;wss can have a maximum of 256 classes. Specify whether to use the liT 111.1 class in initialization ■N. A section is a continuous area with the same attributes in the figure storage space, and includes a virtual screen, 3DW, etc.
Allocate F space etc. In this device, the size of one section is 64K high 1i16 words), and each class has 512 sections. Page
is the minimum Q' that exists in Hypothesis 10-L. At this middle level, data file 1 that cwss calls a work file
− Transfers are carried out between the terminal and the terminal. The size of one page is 4 ha (lilK1 no 1-). FIG. 6 shows an outline of the graphic storage space.

ICAD:J Manto performs graphic input/editing, screen operations, and file operations.) Command 1- consists of the following four parts. ■: 1 communication program l-jgram (lOne command 1 has one communication program. Conversation section Ninomant analysis section semantically analyzes the modification parameters passed.Using the conversation section graphic data analysis section The graphic parameters are retrieved and the corresponding column 1 (processing program is started).

■Command processing program. ■A program that calls the conversation section graphic data analysis section (a program that defines the standard syntax for performing the syntactic analysis of the conversation section graphic data analysis section). ■Attribute management program (sets attribute data, etc. that are commonly handled among multiple commands to C0M0N, and performs a pause).

[Problem that the invention seeks to solve]

In addition to inputting graphic data from the keypad FKB, it is also input from the tablet T[3. It is more convenient to input coordinates of points and designate graphical elements from a tablet keyboard. When you move the stylus (not shown) with 7l-TB-1-, the cursor moves on the graphic display screen Gl) in accordance with the movement, and the cursor on the screen moves. When the cursor is moved to a desired position and the stylus is pushed to the Tazorezo 1, the point coordinates of the desired position are input into the ICAD. In order to input the coordinates of a contact point using the keyboard KB, it is necessary to press keys such as XX for the X coordinate of the contact point and XX for the Y coordinate of the contact point, so it is easier and faster to use a tablet. To indicate a graphical element move the stylus on the tablet and then press G.
Move the cursor on the screen of D, and when the cursor comes over the graphic element, press Star f on the tablet.
That's fine.

In CAD, there are many 19 projects, such as drawing a tangent from a point P to a displayed circle, or drawing a straight line from a point P to the end of a displayed line segment. In such a case, the conventional method is to input the command "LINE", then press the point P on the screen (operate the stylus in this way on the tablet, hereinafter), and then input the command "Find contact point". ”
Or, after inputting the command I' for "Find the end point," click on the entity on the screen, in this case a circle or line segment. The contact point or end point is buried, line segment data connecting the point P and the contact point or end point is created, and it is sent to GD and displayed.

However, in CAD, most of the lines drawn from point P to the circle are tangent lines, and lines drawn from point P to the center of the circle are almost never drawn. Also, the line drawn to the upline segment of point P is a line drawn to the end point of the line segment, and is almost never drawn to the midpoint of the line segment.

In such a situation, it is wasteful to have to input each cloak of ``Find the contact points'' and ``Find the end points'' and make CJs, which impairs operability.

The present invention is a CAD system that improves clutter and improves operability.
The aim is to provide a system.

Means to Solve Problem c] The present invention allows inputting the coordinates of a point of contact by pressing the stylus on a point on the area (-1, etc.), and pressing the stylus on a graphical element in the area (-f +3). In the method of drawing a line at a specific point on an element in a CAD system that has the function of specifying the graphical element by Automatically finds the tangent point that is close to the specified point of the circle element among the points where it touches the circle element, creates a tangent line that connects the tangent point and the point 011, and after inputting the point coordinates, defines one line segment element.) Kotoki is characterized by automatically finding an end point near the specified point of the line segment element and creating a straight line connecting the end point and the point.

[Function and Examples]

To explain using Figure 1, when drawing a tangent to a circle, the first
After inputting the command l “LINE” as shown in the figure (al),
Hit point P2, then hit circle C. Since there are two tangents from the point P2 to the circle C, a point P1 on the circumference near the point where the desired tangent on the other side will touch the circle C is set as the hit point for the circle C. By shifting in this way, the desired tangent line l is drawn as shown in the figure. There is no need to input command 1 of ``Find the tangent point'' before pressing on circle C.

In exceptional cases, a straight line connecting the center point of the circle C and the point P2 may be drawn, but in this case, the line is drawn as usual.
NE" input, point P2 hit, l man F Find the center of the circle" input, circle C hiso 1. In other words, if there is no command before the hit of circle C, it will automatically interpret the command I of ``Find the point of contact'' as being omitted, and complement it.
Process. Note that the calculation method for determining the tangent line is well known, and the specific calculation method will be omitted.

When drawing a straight line to the end point, as shown in Figure 1 (I)): 1 Input "L I N E" (multiple, point 1) 2
, and then press the line segment LI. Line segment L
Since there are two end points of I, the one point P1 of the line segment L, 1 is set near the desired end point. In this way, as shown in the figure, a straight line r7 connecting point P2 and the desired end point of line segment +-1. ! is drawn. Note that the coordinates of the end points of the line segments connecting the lines are known, and the method of pruning straight lines connecting the points is well known.
The specific calculation method tJ will be omitted.

When drawing a line segment connecting the midpoint of line 3L+ and point P2, proceed as usual. That is, command 1 "LINE" is input, point P2 is hit, command "Find the midpoint of the line segment" is input, line segment 1 is hit.

A program that performs such processing is built into the CDS (set it as SDS command 1: above).

Depending on the user, the line drawn from a point to a circle may be mostly a line drawn from a point to the center point of the circle, but in that case, it may be possible to change it in that way.

(Effects of the Invention) As described above, the present invention has the advantage of simplifying and speeding up drawing in a CAD system.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the present invention, FIG. 2 is a block diagram showing an overview of a CAD system, and FIGS. 3 to 6 are explanatory diagrams of each part of the CAD system. In the drawing, C is a circle, L is a tangent, and L2 is a straight line connecting the end point of line segment L+ and point P2. ('i) Circle A tlj 11'Lpr'Z time j11 figure

Claims (1)

[Claims] In a CAD system that has the function of inputting the coordinates of a point using a coordinate input means and specifying a graphical element on an area, when a circular element is specified after inputting the point coordinates, the point Among the points where a straight line extending from the circle touches the circle element, the point of contact close to the designated point of the circle element is automatically found, and a tangent line connecting the point with the point is created, and a line segment element is specified after inputting the point coordinates with the stylus. A method for drawing a line to a specific point on an element, the method comprising: automatically finding an end point close to a designated point of the line segment element and creating a straight line connecting the end point and the point.