JP2713219B2 - Graphic display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphic display device for displaying a graphic to be edited in real time.

[0002]

2. Description of the Related Art Conventionally, some document creation devices such as a Japanese word processor have a drawing function capable of displaying a figure drawn by a line. When a figure is edited (moved, copied, etc.) in this type of document creation apparatus, the figure to be edited is displayed in real time. In this case, a range to be edited is specified, a line pattern is generated by a target figure (stored in the display memory) within the range, an exclusive OR of the line pattern and display data is calculated, and the calculation result is obtained. It is common to display a graphic based on the. The reason for using the exclusive OR is that, when the exclusive OR is calculated for the target graphic, when the graphic is deleted, the exclusive OR is calculated again for the target graphic.
This is because only the target graphic can be erased without erasing the non-target graphic already written.

[0003]

However, if this method is used, if there are even numbers of lines on the same line, the overlap will disappear. For example, there are a rectangular figure as shown in FIG. 5A and a linear figure as shown in FIG. 5B, and when these figures are displayed in a positional relationship as shown in FIG. When the lines constituting the figure are displayed by calculating the exclusive OR with a line pattern as shown in FIG. 6, as shown in FIG. 5D, the line where the two lines overlap disappears. That is, as shown in FIG. 7, there is a drawback in that graphics on the same line are calculated by exclusive OR, and when the exclusive OR is further calculated, they disappear.

[0004] In addition, a method of not writing a second line on a line already written by exclusive OR can be considered. In this case, it is checked whether or not a line has already been written at a predetermined place. Therefore, there is a disadvantage that the drawing process takes a long time.

An object of the present invention is to calculate an exclusive OR of a line pattern generated based on graphic data of a graphic to be edited and display data stored in a display memory, and obtain a calculation result obtained by the calculation. When the edit target graphic is displayed in real time on the display screen as the display data, even if multiple lines that make up the edit target graphic overlap, the part of the edit target graphic where the multiple lines overlap does not disappear, drawing The object of the present invention is to perform processing in a short time so that a graphic to be edited can be displayed in real time.

[0006]

Means of the present invention include a display storage means for storing at least display data for displaying a graphic on a display screen, and a graphic data for displaying a graphic drawn by a line. A plurality of figure data storage means for storing a plurality of figure data to be edited from a plurality of figure data stored in the figure data storage means, and the plurality of figure data to be edited are displayed on the display screen. In doing so, the graphic data corresponding to the plurality of edit target graphics are read one by one from the graphic data storage means, and a graphic corresponding to the graphic data is drawn based on the read graphic data. A line pattern is generated, and an exclusive OR of the generated line pattern and the display data stored in the display storage means is calculated. Display control means for writing a result to the display storage means as new display data and displaying a graphic based on the written display data, wherein the display control means Each time graphic data corresponding to a graphic is read, a line pattern having a different pattern configuration is generated, and the generated line pattern does not match the display data of the graphic to be edited already stored in the display storage means. It is characterized by the following.

[0007]

The operation of the means of the present invention is as follows. When a plurality of graphics to be edited are designated from among the plurality of graphics data stored in the graphics data storage means, and when the plurality of designated graphics to be edited are displayed on the display screen, the display control means The graphic data corresponding to the plurality of graphics to be edited is read one by one from the storage means, and a line pattern for drawing a graphic corresponding to the graphic data is generated based on the read graphic data. The exclusive OR of the obtained line pattern and the display data stored in the display storage means is calculated, and the calculation result obtained by this calculation is written to the display storage means as new display data, and the written data is written. In addition to displaying a graphic on the basis of the display data, the display control means changes the pattern configuration every time the graphic data corresponding to the graphic to be edited is read from the graphic data storage means. The composed line pattern occurs, already display data edited graphic stored is prevented match the display memory means the generated a line pattern.

Therefore, an exclusive OR of the line pattern generated based on the graphic data of the graphic to be edited and the display data stored in the display memory is calculated, and the calculation result obtained by this calculation is used as the display data. When displaying the graphic to be edited on the display screen in real time, even if multiple lines that make up the graphic to be edited overlap, the graphic to be edited in the area where the multiple lines overlap does not disappear, and the drawing process is shortened. The graphic to be edited can be displayed in real time.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment will be described below with reference to FIGS. The embodiment shows an example in which the present invention is applied to a Japanese word processor capable of displaying graphics. FIG. 1 is a block diagram showing a circuit configuration of a Japanese word processor. The input unit 11 inputs characters and figures. Characters and graphics input from the input unit 11 are input to the CPU 12. The CPU 12 controls each unit based on a control program stored in advance, and in addition to the input unit 11, a RAM 13, a display unit 14,
The printing unit 15 and the external storage unit 16 are connected.
Then, the CPU 12 outputs the character input from the input unit 11,
The figure is stored in the RAM 13. RAM 13 is a CPU
The controller 12 controls writing / reading of character and graphic data, and includes a document data area 13a, a work area 13b, and a display memory 13c. The display memory 13c is a memory for storing display data displayed on the display unit 14. One bit of the display area corresponds to one display dot. If the bit content is "1", the display dot is turned on. .

The display section 14 is composed of, for example, a dot matrix type liquid crystal display device, and displays document data and graphic data. The printing unit 15 is configured by, for example, a thermal printer, and prints document data and graphic data. The external storage unit 16 stores document data and graphic data read from the RAM 13.

Next, the operation of the above embodiment will be described. The graphic input from the input unit 11 is stored in the document data area 13a of the RAM 13. Then, the document data area 13a
The exclusive OR of the figure stored in the display memory 13c is calculated and displayed on the display unit 14. When a graphic is to be edited in real time (moving, copying, etc.), a range is first specified by a cursor or the like, and an exclusive logical OR between the display memory 13c and the line pattern is calculated for the target graphic within the range. Is displayed.

FIGS. 2A to 2D are diagrams showing four line patterns prepared for real-time display. In this case, each line pattern is obtained by shifting the line pattern of FIG. 2A by one dot.

In the drawing process, when drawing a plurality of lines, the first one is a line pattern shown in FIG. 2A, and the second one is a line pattern shown in FIG.
2 is the line pattern of FIG. 2 (2), the fourth is the line pattern of FIG. 2 (4), and the fifth is
Like the line pattern of (1), the line pattern is sequentially changed to calculate an exclusive OR. Then, when one line is displayed, it is displayed as shown in FIG. 3A, and when two lines are overlapped, it is displayed as shown in FIG.
When the lines overlap, they are displayed as shown in FIG. Hereinafter, FIGS. 3 (4), 3 (5), 3 (6), 3 (7),
It is displayed as shown in FIG.

FIG. 4 is a flowchart showing the operation of the drawing process. First, in step S1, binary data "0" is stored in a drawing number register (not shown) built in the CPU 12.
00000000 ”to initialize the storage contents.

In step S2, a line pattern number is determined based on the contents of the drawing number register. That is, in this case, the content of the drawing No. register “00000000”
AND of update data "00000011" (AN
D) is calculated, and a line pattern No. “00000000” is obtained. In this case, the line pattern No. “000000”
"00" designates the line pattern shown in FIG. Similarly, the line pattern No. “00000001” corresponds to the line pattern shown in FIG.
“002” is the line pattern and line pattern No. shown in FIG.
“00000003” corresponds to the line pattern shown in FIG.

In step S3, the range of the graphic data to be edited is specified by the cursor, and the address of the display memory 13c is obtained based on the display position of the cursor. Here, the display position specified by the cursor may be specified by a start point and an end point, or a rectangular range may be specified.

In step S4, the exclusive OR of the graphic data stored in the display memory 13c and the specified line pattern, that is, the line pattern of FIG. 2A is calculated from the address obtained in step S3. The calculation result is stored in the display memory 13c. As a result, the graphic data is displayed in a line pattern as shown in FIG.

Next, in step S5, the content of the drawing No. register "00000000" is incremented by 1, and in this case, it is set to "00000001".

In step S6, it is determined whether or not all line processing has been completed, that is, whether or not drawing processing has been completed for all graphic data to be edited. If YES is determined in the step S6, the process in FIG. 4 ends, and if NO, the process returns to the step S2.

In this case, since there is still graphic data to be processed, NO is determined in step S6 and the process returns to step S2. Hereinafter, similarly to the above, the contents of the drawing No. register “00000001” and the update data “0000”
0011 "and a logical pattern (AND)
No. "00000001" is required. In this case, the line pattern No. “00000001” specifies the line pattern shown in FIG. In step S3, the range of the graphic data to be edited is specified by the cursor, and the address of the display memory 13c is obtained based on the display position of the cursor. In step S4, the exclusive OR of the graphic data stored in the display memory 13c and the line pattern in FIG. 2B is calculated from the address obtained in step S3, and the calculation result is stored in the display memory 13c. It is memorized. As a result, the graphic data is displayed in a line pattern as shown in FIG. Next, in step S5, the content of the drawing No. register “00000001” is incremented by 1 to “00”.
000002 ”. Thereafter, the processes of steps S2 to S6 are repeatedly executed as described above until YES is determined in step S6.

When the graphic to be edited is to be erased, for example, when the graphic to be edited is drawn at a new display position in accordance with the editing processing, the exclusive OR of the graphic to be edited by the drawing processing in FIG. Is calculated again, so that only the graphic to be edited can be erased without erasing other graphics other than the graphic to be edited already written in the display memory 13c.

[0022]

According to the present invention, the exclusive OR of the line pattern generated based on the graphic data of the graphic to be edited and the display data stored in the display memory is calculated and obtained by this calculation. When displaying the graphic to be edited on the display screen in real time with the calculation result as display data,
Even if multiple lines that make up the edit target shape overlap, the edit target shape in the portion where the multiple lines overlap does not disappear,
The graphic to be edited can be displayed in real time by performing drawing processing in a short time.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a circuit configuration.

FIG. 2 is a diagram showing a plurality of line patterns.

FIG. 3 is a diagram showing a display state of a graphic.

FIG. 4 is a flowchart showing an operation.

FIG. 5 is a diagram illustrating a display example of a graphic.

FIG. 6 is a diagram illustrating an example of a line pattern.

FIG. 7 is a diagram illustrating a state in which graphic data is calculated by exclusive OR.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Input part 12 ... CPU 13 ... RAM 14 ... Display part 15 ... Printing part 16 ... External storage part

Claims (1)

(57) [Claims] 1. A display storage means for storing at least display data for displaying a graphic on a display screen; a graphic data storage means for storing a plurality of graphic data for displaying a graphic drawn by a line; A plurality of graphics to be edited are designated from among the plurality of graphics data stored in the graphics data storage means, and when the plurality of designated graphics to be edited are displayed on the display screen, the plurality of graphics to be edited are read from the graphics data storage means. The graphics data corresponding to the plurality of graphics to be edited are read one by one, and a line pattern for drawing a graphics corresponding to the graphics data is generated based on the read graphics data. The exclusive OR of the line pattern and the display data stored in the display storage means is calculated, and the calculation result obtained by this calculation is updated as new display data. Display control means for writing to the display storage means and displaying a graphic based on the written display data, wherein the display control means reads the graphic data corresponding to the graphic to be edited from the graphic data storage means A graphic display device characterized in that a line pattern having a different pattern configuration is generated every time, and the generated line pattern does not match the display data of the graphic to be edited already stored in the display storage means. .