JPS60118887A - Cursor mark display system for graphic dispaly unit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cursor mark display method for a graphic display gray device used as a man-machine interface for computer systems and the like.

[Prior art]

Graphic display devices that divide a display area into m pixels in the horizontal direction and n pixels in the vertical direction and display an image for each pixel have become indispensable as man-machine interfaces for computer systems.

Conventionally, this type of graphic display device has a structure in which image information to be displayed is stored in an image memory having a storage capacity of the same number of bits as the number of pixels in the display area, and this image information is sequentially read out and displayed as an image. was, but
Recently, the image memory has a storage capacity that can store image information of an image with a display area larger than the actual display area, and the image information of a part of this image memory is extracted for each display area and displayed. A configuration in which a so-called virtual image area is provided and a portion of a large amount of display information or a large area image can be freely extracted and displayed has been put into practical use.

By the way, in a graphic display device having such a virtual image area, when modifying an image at a desired pixel position in the virtual image area, a cross-to-cross crane mark is displayed at the display position of this image, This allows the user to specify a corrected image. That is, as shown in FIG. 1, the pixel coordinates (X.

When modifying the image of Y), the pixel coordinates of this image (Xt
A red crane mark 2 is displayed on the cross in Y), and a corrected image is designated by this. At this time,
There are mxn crosshair cursor marks 2 (m(M,
If it is in the display area 3 consisting of pixels of n < N Pixel dust of red crane mark on Le Cross inside t11. (x, y) is calculated, and this pixel coordinate (
A crosshair cursor mark is displayed on the screen (x, y).

However, in the prior art, the pixel dust i(,) of the red crane mark crosses within the display area 3.

Since y) is calculated by a subtraction circuit, there is a drawback that the scale of the subtraction circuit becomes large when the number of pixels is large. In addition, since it is a dedicated subtraction circuit, there is no flexibility when changing the size of the virtual image area, and the subtraction circuit has to be changed every time the size of the virtual image area is changed. .

[Purpose of the invention]

The present invention has been made in view of these drawbacks, and its purpose is to provide a cursor for a graphic display device that is flexible in changing the size of a virtual image area and that can display a cursor mark with a simple configuration. The purpose of the present invention is to provide a mark display method.

[Structure of the invention]

The present invention stores image information in units of a predetermined number of pixels in an image memory as a set of image information groups, and a storage area for the set of image information groups displays an image corresponding to the image information group of the set. The structure has an additional storage area for 1-bit cursor display control information indicating whether or not there is a cursor mark displayed in the clothing area to be displayed.
) Set the cursor display control information in the image information group storage area corresponding to the cursor mark display position set when setting the cursor mark display position, and use the cursor display control information when performing a single display operation for the display area. Generated as a cursor display timing signal, and retains position information indicating the pixel position of sequentially displayed images at the time this cursor display timing signal is generated, and this retained position information matches subsequent position information. The device is configured to generate a cursor mark display signal at the display timing.

〔Example〕

The present invention will be explained below based on Examples.

FIG. 2 is a block diagram showing an embodiment of the present invention,
The image memory 4 has 1 in the horizontal direction as shown in FIG.
Image information corresponding to 6 pixels]]. ~D□5 are stored as one set in one memory address. Also, this 1
Picture information of the group. A 1-bit storage area 40 is added to the memory address for storing -D□5, and this storage area 40 contains image information. - Cursor display control information CT representing whether or not a cursor mark is displayed in the section in which the image corresponding to 5 is displayed is stored. This cursor display control information CT is set to CT=11# or CT- by the processing device 5 when setting the cursor mark setting position (XIY) in the virtual image area.
Set as '0'.

That is, 16-bit image information stored at each address of the image memory 4. -D15 are read out simultaneously in parallel during display operation, and these 16-bit image information. −
Each address A(0°0), A(1,0
), . . . A(1,,N) are neatly allocated within the virtual image area 1 as shown in FIG. Therefore, for example, if a cursor mark is set at the coordinate position of X=31 Y=15, the cursor mark in this case is A(L,N)=A(2,0).

A (2t i ) t... Image information of the address of A(2,N). ~In the display section of the image corresponding to Dis and A(L,N)=A(0,1), A(1,1),...
- Since it is sufficient that the image is displayed within the display area of the image corresponding to the image information of address A(L, 1), the processing device 5 sets the cursor mark based on the set position coordinates (x, y) of the cursor mark. The address A(L
CT-11N indicating that the cursor mark should be displayed at this address A (L, N).
cursor display control information CT is set.

For example, in the above example, A(L,N)=A(2°0
), A(2,1), A(2,2), ...A(2,N)
address and A(0,1), A(1,1), A(2
,1),...C at the address of A(r-' r t )
The cursor display control information CT of "T-61" is set.

The cursor display control information CT stored in the image memory 4 in this way is set to 1 when the display area 2 is set within the virtual image area that includes the cursor mark setting position.
6-bit image information. -D15 is read simultaneously and output as the cursor display timing signal CTS. This cursor display timing signal CTS is input to the X register 6 and Y register 7 as a data set signal. At this time, current display pixel position information x(t) in the horizontal direction in the display area is input to the X register 6 from the dot counter 8 which counts the dot clock DCKi corresponding to the display cycle of the image of one pixel, and
Current display pixel position information y(t) in the vertical direction in the display area is input to the register 7 from the raster counter 9 that counts the horizontal synchronization signal H8. Therefore, if the origin coordinates (t, j) of the display area are (0, 0), the cursor display control information CT stored at this address at the timing when the memory content of address A (2, 0) is read out Display pixel position information x (t) of x(t)-16 is set in the X register 6. That is, the positional information (t)=16 of the first bit Do of the address A(2,0) based on the origin coordinates (1) of the display area is set in the X register 6. This X register 6 contains addresses A(2°1), A(2,2), . . . A(2,
Similarly, at the timing when the memory contents of N) are read out, the address A based on the origin coordinates (i) of the display area is
(2,1), A(2°2), . . . the first bit D of A(2,N). The position information x(t)-16 is set.

On the other hand, addresses A(0,1) and A(i
ti)--... At the timing when the storage contents of A(L, 1) are read, the origin coordinates of the display area (j
) based on addresses A(0,1), A(1°1),
...The position information y(t) of A(L, 1) is set to 1. The position information y(t) set in the Y register 7 is input to the comparator 10, where it is calculated from the raster counter 9. A match is found with the configured device information y(t). As a result, when the two match, the match signal EQy is sent to the comparator 1.
Output from 0. This coincidence signal EQy is then sent out via the OR gate 11 as a horizontal cursor mark display signal.

On the other hand, the position information x(t) set in the X register 6 is input to the comparator 12, where the dot counter 8
There is a match with the device information x (t) consisting of x (t). As a result, when the two match, the comparator 12 outputs a match signal EQx. Here, the match signal EQx output from the comparator 12 is the address A (2p O), A
(2,1),・A (first pitch at 2°N))Do
There is no direct correspondence with the display position of the cursor mark in the hydraulic direction. Therefore, this coincidence signal EQx is the dot clock DC.
The output information Δ of the hexadecimal counter 13 that counts K, (
1) and addresses A(2,o), A(2,1), -A(2
The bit position information BN indicating the bit position of the cursor mark at 0°N) is given as an enable signal for the comparator 15 for checking the match with the bit position information BN. That is, the comparator 15 has 16
Bit position information Δ廁) corresponding to the bit position of the 16-bit image information is input from the hexadecimal counter 13, and the bit position of the cursor mark in the 16-bit image information is determined. The bit position information BN shown in FIG. Comparison operations are allowed only at specified timings. As a result, the coincidence signal E
When Qx is generated and the information Δx(t) and BN match, the comparator 15 generates a match signal EQΔX. This coincidence signal EQΔX is sent out via the or dart 11 as a vertical cursor mark display signal.

To summarize, the comparator 12 detects the display timing of a set of image information including the display of a cursor mark, and the comparator 14 detects the display timing of the cursor mark in this set of image information. The cursor mark display signal C8R is sent out at the detected display timing.

Here, bit position information B output from the register 14
N is set by the processing device 5 when the cursor mark position coordinates (X, Y) are set. Since the addresses of the image memory 4 are arranged in an orderly manner in the virtual image area 1, this bit position information BN can be taken as the remainder when the position coordinate X is divided until the remainder becomes "16" or less. As a result, even if the display area is set to an arbitrary position, the cursor mark is displayed at the set position.

In this actual km example, the image information stored in one address is 16 bits, but the information is not limited to this.

〔Effect of the invention〕

As is clear from the above description, the present invention provides a method for determining whether or not a cursor mark is displayed within a memory address that stores a set of image information in a section where an image corresponding to this set of image information is displayed. 1-bit control information indicating whether or not the cursor is displayed is added and stored, and this 1-bit control information is generated as a cursor display timing signal during image display operation, and this signal sets the origin coordinates of the virtual image area as a reference. The circuit has a circuit configuration that converts the cursor mark setting position information into position information based on all origin coordinates of the display area.
It is possible to display a cursor mark without using a subtraction circuit, and it is also possible to cope with changes in the size of the virtual image area without changing the circuit.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the relationship between the virtual image area and the display area, FIG. 2 is a block diagram showing an embodiment of the present invention, FIG. 3 is a memory map showing how image information is stored, and FIG. 4 is a diagram showing the relationship between the virtual image area and the display area. FIG. 3 is a diagram showing the relationship between information storage addresses and virtual image areas. DESCRIPTION OF SYMBOLS 1...Virtual image area, 2...Cross crane mark, 3...Display area, 4...Image memory, 5...Processing device, 6...X register, 7... Y
Register, 8... Dot counter, 9... Raster counter, 10°12.15... Comparator, 13... 1
Hexadecimal counter, 14... register. Figure 1 Figure 2 1/1 Figure 4

Claims (1)

[Claims] Image information of an image to be displayed is stored corresponding to each pixel of a display area consisting of a plurality of pixels divided in the horizontal and vertical directions, and the image memory that stores this image information is larger than the display area. A graphic display is configured to have a virtual image area that can store image information of an image of an area, and reads out the image information stored in the virtual image area of the image memory in a display area I and displays a corresponding image. In the apparatus, the image memory stores image information in units of a predetermined number of pixels as a set of image information groups, and the storage area for the set of image information groups displays images corresponding to the image information groups of the set. The configuration includes an additional storage area for 1-bit cursor display control information indicating whether or not there is a cursor mark display in the display section to be displayed, and the cursor mark display set at the time of setting the cursor mark display position in the virtual image area. Cursor display control information in an image information group storage area corresponding to a position is set, and the cursor display control information is generated as a cursor display timing signal during an image display operation for the display area, and the cursor display timing signal is generated. To hold position information indicating pixel positions of images that are sequentially displayed at a time, and to generate and display a cursor mark display signal at a display timing when this held position information and subsequent position information match. A cursor mark display method for a graphic display device characterized by: