JPH05242255A - Graphic display device - Google Patents

Abstract

PURPOSE:To accelerate plotting speed and display erasing speed by shortening the processing time of a color setting command. CONSTITUTION:Graphic information generated by a user is converted from a logical coordinate system to a physical coordinate system, and is developed on a frame buffer 14, and is displayed on the screen of a CRT display in a color set on a color register 20. A background color register 22 is provided in parallel with the color register 20. The color set on the frame buffet 14 as a display color is the content of either the color register 20 or the background color register 22, and it is set by switching by a register switch 24 under the control of a graphic processor 12. When re-plotting is performed, the register switch 24 is switched to a color register 20 side in advance. Adversely, when display erasure is performed, the switch 24 is switched to a background color register 22 side.

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 capable of displaying graphics in multiple colors, and more particularly to improving the drawing speed thereof.

[0002]

2. Description of the Related Art In recent years, a graphic display device has been used as an output device of a computer. As a graphic display device,
For example, a structure as shown in FIG. 4 is known, and an improvement in drawing speed is required for this type of device.

The device shown in this figure includes a segment buffer 10, a graphic processor 12, a frame buffer 14, a video generator 16, and a CRT display device 18.
And a color register 20. Segment data, which is graphic information created by a user, is registered in the segment buffer 10, and the graphic processor 12 converts the segment data from a logical coordinate system called a work coordinate system to a physical coordinate system and stores it on the frame buffer 14. Expand to. The video generator 16 generates a video signal based on the data expanded on the frame buffer 14, and causes the CRT display 18 to display a screen.

Further, this conventional device is a device capable of displaying graphics on the screen of the CRT display 18 in color. The segments registered in the segment buffer 10 are a set of graphic information called graphic primitives. A graphic primitive is a basic element such as a straight line, a circle, or a character, and various attributes are given to these graphic primitives.

The attributes given to the graphic primitives include, for example, attributes such as color, line type, and character size.
The graphic processor 12 issues a color setting command using the attribute relating to color among these, and sets the display color in the color register 20. The frame buffer 14 is
The CRT display 18 according to the color set in the color register 20
It is a frame buffer that can display graphics on the screen. That is, the frame buffer 14 has planes for each color, and which plane to write to is selected according to the value of the color register 20.

FIG. 5 shows the contents of the color setting command in this conventional example. Graphic processor 1
2 is a color setting command when drawing (redrawing) a graphic already registered in the segment buffer 10 or when deleting a graphic displayed on the screen of the CRT display 18 (display deletion). Issue. When the color setting command is issued, the graphic processor 12 determines the mode (100) and determines whether it is redrawing or display erasing. The graphic processor 12 executes step 102 when it is determined to be redrawing, and executes step 104 when it is determined to be display erase.

In the case of redrawing, the graphic processor 1
2 sets the color designated by the color setting command in the color register 20. In this case, on the screen of the CRT display device 18, color display is executed according to the color attribute of the graphic primitive related to the segment registered in the segment buffer 10.

In the case of display erasure (including segment deletion), the graphic processor 12 sets the background color in the color register 20. That is, the same figure is again drawn in the background color on the figure displayed on the screen of the CRT display 18. Therefore, the graphic is erased from the screen of the CRT display 18.

[0009]

As described above, the conventional display erasing is performed by the color setting command. That is, it is necessary to determine whether to perform redrawing or display erasing according to the color setting command. Therefore, for example, it takes a very long time to process a segment that frequently uses color commands.

The present invention has been made to solve the above problems, and an object thereof is to improve the speed of drawing and erasing by shortening the processing time of the color setting command. ..

[0011]

In order to achieve such an object, the graphic display device of the present invention comprises:
A segment buffer in which graphic information having attributes relating to display colors is registered, a frame buffer for storing graphic information in a coordinate system corresponding to the screen and displaying a graphic related to the graphic information in the set color on the screen, and a segment buffer Redrawing means for reading the graphic information from the frame to a coordinate system corresponding to the screen and writing it in the frame buffer, a color setting command issuing means for issuing a color setting command based on the attribute, and a display by a frame buffer according to the color setting command In a graphic display device including a color setting unit for setting a color, a background color setting unit for setting a background color as a display color of a figure by a frame buffer, and a color setting by the color setting unit for re-drawing in advance. When deleting the display, the color setting by the background color setting means is set to be valid in advance. Characterized in that it comprises switching means for placing the.

[0012]

In the present invention, the color setting by the color setting means is validated beforehand when redrawing, and the color setting by the background color setting means is validated beforehand when the display is erased. Therefore, when a color setting command is issued, the color specified by this command may be set by the color setting means regardless of whether it is redrawing or display erasing. When the display is erased, the background color setting means is enabled prior to this, and the background color is set in the frame buffer. Therefore, it is not necessary to determine the mode selection according to the color setting command,
The drawing speed and the display erasing speed are improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. The same components as those in the conventional example shown in FIGS. 4 to 5 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 shows a main configuration of a graphic display device according to an embodiment of the present invention. In this figure, only the parts different from the conventional example shown in FIG. 4 are shown, and the segment buffer 10, the video generator 16, the CRT display 18, etc. are omitted.

A feature of this embodiment is that, as clearly shown in FIG. 1, a background color register 22 is provided in parallel with the color register 20, and a register switch is provided at the subsequent stage of the color register 20 and the background color register 22. 24 is provided.
That is, what is set as the display color in the frame buffer 14 is either the content of the color register 20 or the background color register 22, which is set under register control under the control of the graphic processor 12. Bowl 2
It is switched and set by 4.

FIG. 2 shows the operation flow of this embodiment. As shown in this figure, in this embodiment, the register switching unit 24 is switched to the color register 20 side in advance when redrawing (106). On the contrary,
When the display is erased, the register switch 24 is switched to the background color register 22 side (108). Step 106
After executing, the process shifts to the redrawing process (110) using the color setting command as in the conventional method, and after step 108, the background color is set in the background color register 22 (112) and then the redrawing process ( 110).

FIG. 3 shows the color setting operation in the redrawing process (110). As shown in this figure,
In this embodiment, when the color setting command is issued, the graphic processor 12 does not execute the conventional mode determination (100), but immediately executes step 102. That is, even when the display is to be erased, the color corresponding to the color attribute value of the primitive is set in the color register 20.

In this embodiment, the operation in accordance with the color setting command is simplified because the background color register 22 is used as shown in FIG. That is, when the display is erased, the color register 20 is invalid, the background color register 22 is valid, and the display color is set (background color setting) based on the background color register 22. It is not necessary to change the color set in the color register 20 according to the command. As a result, the operation according to the color setting command is simplified, and the redrawing of the figure and the display erasing operation become faster.

In the above description, the attribute value of the graphic primitive related to the segment registered in the segment buffer 10 and the numerical values set in the color register 20, the background color register 22, etc. are not mentioned. The present invention is not limited to such contents.

[0020]

As described above, according to the present invention,
Since the background color setting means for setting the background color as the display color of the figure by the frame buffer is provided and the color setting by the background color setting means is enabled in advance when the display is erased, the operation according to the color setting command is simple. The redrawing speed and the display erasing speed are increased. As a result, a graphic display device with improved performance can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main configuration of a graphic display device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of this embodiment.

FIG. 3 is a flowchart showing a flow of operations corresponding to a color setting command in this embodiment.

FIG. 4 is a block diagram showing a configuration of a graphic display device according to a conventional example.

FIG. 5 is a flowchart showing a flow of operations corresponding to a color setting command in a conventional example.

[Explanation of symbols]

 10 segment buffer 12 graphic processor 14 frame buffer 16 video generator 18 CRT display 20 color register 22 background color register 24 register switch

Claims (1)

[Claims] 1. A segment buffer in which graphic information having an attribute relating to a display color is registered, and a frame for storing graphic information by a coordinate system corresponding to the screen and displaying a graphic related to the graphic information on the screen in a set color. The buffer, the redrawing means for reading the graphic information from the segment buffer into the coordinate system corresponding to the screen and writing it in the frame buffer, the color setting command issuing means for issuing the color setting command based on the attribute, and the color setting command In a graphic display device including a color setting means for setting a display color according to a frame buffer, a background color setting means for setting a background color as a display color of a figure by the frame buffer, and a color setting means for redrawing. The color setting is made valid in advance, and when the display is erased, the background color setting means sets the color. Graphic display device, characterized in that it comprises a switching unit to keep the previously enabled, the.