JPS60196836A - Vector drawing control system - Google Patents

Abstract

PURPOSE:To form ruled lines easily on the basis of hand-written input by correcting a drawn segment to a segment parallel to a coodinate axis when an inclined angle to the drawn segment designated by a coordinate input pen from the coordinate axis is included in a previously set angle range. CONSTITUTION:A coordinate input part 1 generates moving magnetic fields having different frequencies along rectangular coordinate axes and also detects the moving magnetic fields through an input pen 2. The coordinate position designated by the input pen 2 is detected on the basis of the relation between an excited phase and a detected phase which are transferred from coordinate detecting parts 3, 4 to a microprocessor. When a vector drawing mode is set, the coordinate values (X1, Y1) and (X2, Y2) of the 1st and 2nd pen-down operations through the input pen 2 are stored in a memory 7 and ¦(Y2-Y1)/(X2-X1)¦=alpha and ¦(X2-X1)/(Y2-Y1)¦=beta are calculated. When it is defined that a set angle is theta and the values of alpha and beta are smaller than tan theta, the segments are the ones parallel to X and Y axes respectively.

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to a vector drawing control method in which a line segment parallel to a coordinate axis can be drawn by handwritten input in a coordinate input device of an orthogonal coordinate system. .

Prior Art and Problems In the conventional vector drawing method, the coordinate input surface of a coordinate input device in a rectangular coordinate system is indicated with an input pen, and the first pen-down point of the input pen is the starting point, and the next pen-down point is the ending point. This draws a line segment that connects the two. Therefore, when drawing a line segment parallel to the X-axis or Y-axis, even a slight inclination is input as is, so that the inclined line segment is displayed on the display device. Particularly in a normal rusk scan type display device, since there are differences in the displayed line segments, it is necessary to use a ruler or the like to draw ruled lines for tabulation.

Purpose of the Invention The present invention aims to correct line segments that are inclined within a preset angle range by regarding them as parallel to the coordinate axes, thereby making it possible to easily draw line segments parallel to the coordinate axes by handwriting input. This is the purpose.

Structure of the Invention The present invention provides a coordinate input device using an orthogonal coordinate system in which coordinates are input by pointing a coordinate input surface with a coordinate input pen, and in which the inclination angle of a drawn line segment specified by the coordinate input pen with respect to the coordinate axis is determined. means for determining whether or not the angle is within a preset angle range; and when the means determines that the angle is within the set angle range, the drawn line segment is drawn as a line segment parallel to the coordinate axis by correcting the inclination angle of the drawn line segment. It is equipped with a means that allows parallel lines to be easily drawn using handwriting skills.

Examples will be described in detail below.

Embodiment of the Invention FIG. 1 is a block diagram of an embodiment of the present invention, in which 1 is a coordinate input section, 2 is an input pen, 3 is a coordinate detection section, 4 is a detection section for detecting pen down, pen up, etc. 5 is a microprocessor (MPU5.6 is a memory such as a read-only memory (ROM) that stores processing programs, etc., and 7 is a random access memory that writes and reads various data.
8 is a display control unit (DSC) that processes display data; 9 is a display device such as a cathode ray tube (CRT); and 10 is a display memory (DM) that stores display data for one screen. be.

The coordinate input section 1 and the input pen 2 can adopt various already known configurations. For example, by generating moving magnetic fields of different frequencies along the orthogonal coordinate axes, the input pen 2 to detect this moving magnetic field and detect the coordinate position indicated by the input pen 2 based on the relationship between the excitation phase and the detection phase, the input pen 2
A coil for detecting a magnetic field and a contact point for detecting pen down are provided in the detecting section 4 to which the input pen 2 is connected.
A configuration is provided in which a contact ON/OFF identification signal and a coil output signal are respectively transferred to the microprocessor 5 via a common bus.

Further, the coordinate input section 1 is provided with a plurality of coils in the X and Y axis directions, each of which is excited at a different phase, thereby generating a single moving magnetic field. In the coordinate input device of the orthogonal coordinate system having such a configuration, the coordinate detecting section 3 performs excitation control, and the input coordinate values can be detected using the detection signal from the input pen 2. Of course, it is also possible to adopt a configuration in which the microprocessor 5 performs the process of calculating the coordinate values.

The microprocessor 5 temporarily stores the detected coordinate values in the memory 7 according to the program stored in the memory 6, performs predetermined data processing, and then transfers them to the display memory IO via the display control unit 8. The contents of this display memory 10 are added to the display device M9 and displayed under the control of the display control section 8.In addition, in the vector drawing mode, the inclination angle of the line segment is within a predetermined angle range. In order to determine whether or not the set angle θ is the same, data on the set angle θ is stored in the memory 6 or 7.

Enter the vector drawing mode by inputting from a keyboard (not shown), etc., and input the coordinate values of the first pen down by the input pen 2 to the coordinate input section 1 (XI, yl> Then, this coordinate value is detected by the coordinate detection unit 3 and temporarily stored in the memory 7. If the coordinate value of the next pen down is (xz,)'2), this coordinate value is also detected by the coordinate detection unit 3. and stored in the memory 7. Since the microprocessor 5 is in vector drawing mode, it calculates a straight line between the first paydown coordinate value and the next pendown coordinate value, and calculates the inclination angle of the line segment. In the conventional example, the process was simply to draw a straight line.

As with the front fence, if the set angle is θ, if the straight line between the coordinate values is within the set angle range as shown in the figure, it is determined that this is a straight line drawn parallel to the coordinate axis, and ( X2
．． Correct yr) to (X2. yl) to obtain (b) in Figure 2.
As shown in the figure, line segments parallel to the X axis are displayed. That is, in the case of , it is regarded as a line segment parallel to the X axis, and in the case of
Correction processing is performed by regarding it as a line segment parallel to the axis.

FIG. 3 is a flowchart of an embodiment of the present invention;
At the start of vector drawing, input the coordinate value (XI,)'I) when the pen down is detected, then judge whether it is a pen amplifier or not, and after pen up, input the coordinate value (XI,)'I) when the next pen down is detected. Input X z, )' 2). Next, it is determined whether the condition of formula +1) is satisfied, and if the condition is satisfied, that is, if the inclination angle of the line segment is within the set angle range, the line segment is considered to be parallel to the X axis. Therefore, we set y2 = 3'I, and if it does not hold, it is determined whether the condition of equation (2) holds, and if it holds, it is regarded as a line segment parallel to the Y axis. Let x2=xl, take (X+, yI) as the starting point,
A vector is drawn with (x2.'I2) as the end point, and (X2.)'z) as the next starting point. Such inclined line segments within the set angle range are corrected to line segments parallel to the coordinate axes and displayed on the display device 9.

In the above-mentioned embodiment, when an instruction is given with a felt-tip pen on a whiteboard, the coordinate input section 1 is formed on the whiteboard, and a contact point for pen-down detection is provided on the felt-tip pen, an instruction is given on the whiteboard. , only the starting point and ending point of the line segment are entered, and the line segment is displayed on the display device 9 by vector drawing. Therefore, when a plurality of line segments are drawn on the whiteboard, it is unclear which line segment was drawn. Therefore,
Even when a predetermined line segment is drawn in the coordinate manual section 1 so that the display content is almost the same as that of the display device 9, if the inclination angle of the line segment is within the set angle range, the coordinate axes and It is possible to draw a vector by determining it as a parallel line segment.

For example, as shown in Figure 4 (Ta), draw a line segment from the initial pen-down coordinates (X+, )'+), set the pen-up coordinates (xz, yz), and draw a vector. To show this, if we move the pen down to a coordinate close to the pen up coordinate value and let the coordinate value be (x3, y3), then the first pen down coordinate value (xI, yI) and the next pen up coordinate value (xz.

yz), the above-mentioned Equation 11 and Equation (2) are judged, and it is judged whether the slope angle of the line segment is within the set angle θ range. If the conditions are satisfied, for example, Figure 4 (
As shown in b), a line segment parallel to the X axis is drawn manually with y3=yI.

FIG. 5 is a flowchart of the above-mentioned embodiment, and shows the coordinate values (X
+, yI), then enter the coordinate value (
Input X2.3'2), input the coordinate value (Xs,)'s) at the time of the next pen-down detection, and determine that the input of the start and end points of vector drawing is complete at the second pen-down detection.
Based on the coordinate values (X+, )'l) and (X21 yz), it is determined whether the inclination angle of the line segment is within the set angle θ range.

That is, it is determined whether the conditions of (11) and (2) are satisfied. (If the condition of (11) is satisfied, x3
=xl, and if the condition of equation (2) is satisfied, then y3=
yI, the coordinate value (xI, yI) is the starting point, the coordinate value (Xa
+y3) as the end point, and the coordinate value (x
a, y3) as the next starting point.

As a means for determining whether or not the angle is within the set angle range, the first
In addition to being realized by the microprocessor 5 as shown in the figure, it is also possible to realize it by a comparison circuit or the like that compares the upper and lower limits of the set angle range and the calculated inclination angle of the line segment. Further, the slope of the input line segment can be easily corrected by rewriting the coordinate values.

DETAILED DESCRIPTION OF THE INVENTION As described in detail, the present invention provides a coordinate input device using an orthogonal coordinate system in which coordinates are input by pointing a coordinate input surface of a coordinate input unit 1 with a coordinate input pen such as the input pen 2. , means for determining whether or not the inclination angle of the drawn line segment with respect to the coordinate axis indicated by the coordinate input pen is within a preset angle θ range; It is equipped with a means to draw a line segment parallel to the coordinate axes by correcting the inclination angle of the line segment, and it is possible to easily draw a line segment parallel to the coordinate axes even in the case of handwritten input, so ruled lines It has the advantage of being easy to create.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2(a),
(b) is an explanatory diagram of input coordinates and display line segments according to an embodiment of the present invention, FIG. 3 is a flowchart of an embodiment of the present invention,
FIG. 4 (al, (bl) is an explanatory diagram of input coordinates and display line segments in another embodiment of the present invention, and FIG. 5 is a flowchart of another embodiment of the present invention. 1 is a coordinate input section; 2 is an input pen, 3 is a coordinate detection unit, 4 is a detection unit that detects pen down, pen up, etc., 5 is a microprocessor (MPU), 6 is a memory such as a read only memory (ROM) that stores processing programs, etc. 7
8 is a memory such as a random access memory (RAM) that writes and reads various data, 8 is a display control unit (DSC) that processes display data, and 9 is a cathode ray tube (CRT).
10 is a display memory (DM) that stores display data for one screen, for example. Patent Applicant Fujitsu Ltd. Representative Patent Attorney Shoji Aitani Representative Patent Attorney Hiroshi Watanabe - Figure 1 Figure 2 (a) (b) Figure 4 (a) (b) Figure 3

Claims (1)

[Claims] In a coordinate input device using an orthogonal coordinate system in which coordinates are input by pointing a coordinate input plane with a coordinate input pen, the inclination angle of the drawn line segment with respect to the coordinate axis specified by the coordinate input pen is within a preset angle range. and a means for drawing the drawn line segment as a line segment parallel to the coordinate axis by correcting the inclination angle of the drawn line segment when it is determined by the means that the angle is within a set angle range. A vector drawing control method featuring: