JPS61157928A - Plotted picture display device - Google Patents

Abstract

PURPOSE:To erase the desired area of a displayed video by approximating a rectangular set area enclosed by a straight line for circumscribing a plotted locus and that vertical against the former to an erasure area and erasing the video in said area. CONSTITUTION:An inner zone maximum and minimum value memory table in a RAM32 is set to '0', x and y coordinates are read through an A/D converter 2. A zone number (i) can be available from the prescribed arithmetic, and the minimum value ximin and the maximum value ximax with respect to a zone (i) are read out of the inner zone maximum and minimum value memory table in the RAM32, and are compared with the coordinates (x). Where x<ximin or ximin=0, the (x) is substituted for the ximin, and where x>ximax, the (x) is substituted for the ximax. Thus the maximum and minimum values in the zone are updated, and continuously the termination of the input of locus coordinates is decided. Then with respect to all zones, data in a picture memory device 4 corresponding to the area enclosed by the ximin, ximax and the zone boundary is set to '0'.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a drawn image display device. In particular, the present invention relates to a drawing-quality partial erasing means.

〔overview〕

The present invention provides a drawing image display device in which a drawing trajectory caused by contact is displayed as an image. This is a simplified configuration of a device that can erase a desired area of a displayed image by approximating this erasing area with a rectangular collection area and erasing the image within this approximated area. .

[Conventional technology]

A conventional graphic image display device that displays a graphic image corresponding to a contact trajectory on a flat plate must be equipped with correspondingly large-scale software in order to partially erase a graphic image that has already been displayed.

[Problems to be Solved by the Invention] [Problems to be Solved by the Invention] ``With such a conventional device, in order to modify a drawn image that has already been displayed, the device becomes expensive and the processing time becomes long. In particular, software for accurately capturing a drawn image of a designated area has the drawback of becoming complicated.

The present invention aims to eliminate this drawback and aims to simplify the construction of a drawing display device that can be partially erased in order to modify an already displayed drawing.

[Principle of the Invention] The principle of the invention will be explained based on FIGS. 3 and 4.

First, the image storage device 15 stores the locus coordinates of the drawn image input from the contact position detection device 1, and the display device 6 visually displays them.

Now, the trajectory coordinates of the drawn image are input to the contact position coordinate detection device 10, the zone determination means 11 determines the coordinates to which this trajectory coordinate belongs, and the zone maximum and minimum coordinate determination means 12 determines whether this trajectory coordinate is within this zone. If the coordinate is larger or smaller than the previously detected coordinates, it is stored in the in-zone maximum or minimum coordinate storage device 13. After all the coordinates of the locus indicating the erased position have been detected, an image is stored corresponding to a rectangular area surrounded by the zone boundary line and the maximum and minimum coordinates in this zone stored in the zone maximum and minimum coordinate storage device 13. The drawn image of the area in the device 15 is rectangular area erasing device 1
4 is erased.

Next, the principle of the process of erasing an area within the image storage device 15 will be explained based on FIG. As shown in Figure 4, the human power position coordinates (x, y) are plotted on a two-dimensional plane indicated by the X-axis and Y-axis.
is expressed. First, the Y-axis is divided into n zones 100. Next, for the input position coordinates (x, y), Zff
A zone z1 where iLSy<zH is obtained. However, ziLn Z ih are the y-coordinate values of the lower and upper boundaries of zone z8, respectively.

For the obtained zi, the maximum value X ismx and the minimum value x! corresponding to 21 in the zone maximum and minimum value storage device 13 are obtained. ,,1ifi and the input coordinates X are compared, and X〉
When X ismx, X is set to xll, and X < X
When i, i, X is set to Xi*in.

X5tn and X1 after the trajectory surrounding the erased area is completed
Regarding the zone where both 11aK exist, Z iL + Z
The area in the image storage device 15 corresponding to the rectangular portion consisting of the four sides of ih+Xisi* and x118 is erased. In FIG. 4, a closed curve 50 is a figure that provides input position coordinates, and a hatched area surrounded by a concave polygon 75 is an area to be erased.

[Means for solving problems]

The present invention provides a position coordinate detection device that detects a two-dimensional position signal from a contact position coordinate specifying means that specifies two-dimensional coordinates on a flat plate by contact, and a drawing locus of the position signal according to the movement of the position signal. The calculation means includes a calculation means for calculating and a display means for displaying the drawing trajectory, and the calculation means comprises:
As a means for solving the above-mentioned problem, the drawn image display device includes means for erasing a portion surrounded by the drawing locus of the position signal input to the position coordinate detection device when the erase mode is specified. The erasing means includes a region identifying means for identifying a region defined by a straight line perpendicular to one coordinate axis of the two-dimensional coordinates of the position signal, and a region identified by the region identifying means to An area definition means for defining an area defined by a straight line passing through a point indicating the maximum value and minimum value of the other coordinate of the position signal and parallel to one coordinate axis, and defined by this area definition means. and means for erasing the displayed image within the area.

[Effect]

If the area of the drawn image to be erased is given by the trajectory caused by contact, then
This locus is cut by a straight line perpendicular to one of the coordinate axes to generate segmented figures.

Furthermore, a straight line parallel to one of the coordinate axes is determined, passing through a point on the periphery of the divided figure that takes the maximum and minimum values of the other coordinate.

The drawn image on the area within the figure, which is a collection of rectangles surrounded by these four straight lines, is erased by the drawn image erasing means.

Although this erasing means does not have a shape that exactly corresponds to the designated area, by making this approximation, the software is significantly simplified and the execution processing time is shortened. Depending on the intended use of the device, the approximation can be set to a level that poses no problem in practice.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS A device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block configuration diagram showing the configuration of the apparatus of this embodiment. FIG. 2 is a flowchart showing the operation of this embodiment device.

First, the configuration of this embodiment device will be explained based on FIG. This embodiment device includes a contact position coordinate detection device 1 and an analog/digital converter (hereinafter referred to as an A/D converter).
2, a microcomputer 3 including a CPU 31, a RAM 32, and a ROM 33, an image storage device 4, and a display device 5. The output of the contact position coordinate detection device 1 is A-
It is connected to the input of the D converter 2, and the output of the A-D converter 2 is connected to the first power of the CPU 3I. The second output of CPU U31 is connected to the input/output of RAM32, and
The third input/output of U31 is connected to the human output of RAM33, the fourth input/output of CPU31 is connected to the first input/output of image storage device 4, and the output of image storage device 4 is connected to display device 5.
connected to the input of

Next, the operation of this embodiment device will be explained based on FIGS. 1 and 2. A program for controlling the CPU 31 is written in the ROM 33, and the CPU 31 takes in the X and Y coordinates from the A-D converter 2 and transfers data to and from the RAM 32 to execute arithmetic processing according to this program. The data is written to the image storage device 4 as necessary. In addition, a contact position coordinate detection device l
Then, an analog electrical signal having a magnitude corresponding to the contact position coordinates is generated and supplied to the AD converter 2.

Next, the program written in ROM33 is transferred to the second
This will be explained based on the flowchart shown in the figure.

First, rOJ is written into all of the zone maximum and minimum value storage tables on the RAM 32 (step 2).

Next, the x and y coordinates are read from the A-D converter 2 (
Step ■). Continuing, the zone number i is obtained by calculating i=y/Zo (step ■), where zo is the width of the zone and i is an integer value. Next, R
The value X taint X iam+t for zone i is read from the in-zone maximum value and minimum value storage table on the AM 32 (step ■).

In the process from step ■ to step ■, it is compared with
<X1. i, or x! When IIi+s=0, d
=m+n dX is substituted, and when x>X immx, X is substituted into Xis□. This updates the maximum and minimum values within the zone. Continuing on, it is determined that the input of trajectory coordinates has ended (step ■), and in step [phase], X i, i□ R and Xtllll
All data in the image storage device 4 corresponding to the area surrounded by llX are set to O (step @).

〔Effect of the invention〕

According to the present invention, a shape substantially close to the shape surrounded by the drawn image is reproduced within a reasonable execution time, and a portion of the drawn image within the range of this shape is erased. This provides a practically useful device that can partially erase a displayed drawn image, although the portion to be erased is not strictly specified.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of an apparatus according to an embodiment of the present invention. Configuration diagram. FIG. 2 is a flowchart showing the operation of the apparatus according to the embodiment of the present invention. FIG. 3 is a block diagram of a program showing the principle of the present invention. FIG. 4 is a schematic diagram showing an erasing area realized by the present invention. ■, lO...Touch position coordinate detection device, 2...A-D
Converter, 3...Microcomputer, 4.15...
・Image storage device, 5.16...Display device, 11...
Zone determination means, 12... Zone maximum and minimum coordinate determination means, 13... Zone maximum and minimum coordinate storage means, 14
...Rectangular area eraser.

Claims (1)

[Claims] (1) A position coordinate detection device that detects a two-dimensional position signal from a contact position coordinate specifying means that specifies two-dimensional coordinates on a flat plate by contact, and calculates a drawing locus of the position signal according to the movement of the position signal. and a display means for displaying the drawn locus, and the arithmetic means erases a portion surrounded by the drawn locus of the position signal input to the position coordinate detection device when an erase mode is specified. In the drawing image display device, the erasing means includes a region identifying means for identifying a region defined by a straight line perpendicular to one coordinate axis of the two-dimensional coordinates of the position signal; A region definition that approximately defines the region defined by a straight line that passes through a point indicating the maximum and minimum values of the other coordinate of the position signal included in this region and is parallel to one coordinate axis. A drawn image display device comprising: means for erasing a displayed image within an area defined by the area defining means.