JPH0384683A - Graphic display system - Google Patents

Abstract

PURPOSE:To shorten plotting time for screen space by directly plotting graphic data which is to be newly plotted in screen space. CONSTITUTION:Graphic data plotted in world space 2 is generated in a world space plotting means 7. The graphic data is converted into the coordinate origin of screen space in a coordinate origin conversion means 8. A screen space plotting means 9 generates graphic data plotted in screen space 3 from graphic data in which the coordinate origin is converted and graphic data is plotted in screen space. Thus, plotting time for screen space is shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a graphic display system that displays graphic data on a screen.

(Prior Art) Graphic display systems display computer output as figures, and use functions to generate characters, dots, lines, arcs, etc. to provide a wide range of displays.

Conventional graphic display systems, for example,
As shown in the figure, drawing is performed in world space based on display commands given from a processor, and a portion of the drawing that is desired to be displayed is copied to screen space and displayed on a display device such as a CRT.

However, in such conventional display methods, each time the world space display content is updated or a specific part is changed, the screen space display content is refreshed and the world space display content is updated. need to be copied.

For example, 640 horizontal dots (40 words) in world space.
When drawing a straight line, the drawing is completed in a processing time of 40 [μS], assuming that one word requires a processing time of 1 [μS]. Then, add this to 640 dots horizontally (40
Word>, when copying to a screen space of 480 dots vertically, 40 words x 480 = 19200 words must be copied, resulting in one 2 [IS]
It takes a lot of processing time.

Therefore, when updating the display content in the world space or changing a specific part, a copy time of 19.2 [ms] is required in addition to the drawing time in the world space.

Furthermore, in the case of 8-color display, three times as many words will be copied, and the processing time will also be three times as long.

(Problem to be Solved by the Invention) As described above, in the conventional display method, it takes a long time to copy from the world space to the screen space, so there is a problem that the required display speed cannot be satisfied. there were.

The present invention has been made to solve these conventional problems, and its purpose is to provide a graphic display system that can significantly improve the display speed of display data.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention draws the entire graphic data in the world space, copies the part of it to be displayed in the screen space, and then displays the data. In a graphic display system for displaying, a world space drawing means for drawing graphic data in world space, a coordinate origin conversion means for converting a world space coordinate origin to a screen space coordinate origin, and a coordinate origin converting means for converting the coordinate origin of the world space to the screen space coordinate origin; A feature of the present invention is that it includes screen space drawing means for drawing graphic data directly in screen space.

(Operation) With the configuration as described above, graphic data to be drawn in the world space is created in the world space drawing means. This graphic data is then converted to the coordinate origin of the screen space by the coordinate origin conversion means.

Thereafter, the screen space drawing means creates graphic data to be drawn in the screen space from the graphic data whose coordinate origin has been converted, and draws it in the screen space.

This significantly reduces the time it takes to draw into screen space.

(Example) FIG. 1 is a block diagram showing an embodiment of the present invention.

The graphic display system shown in the figure includes a processor 1 that outputs display commands, and a CR that draws in a world space 2 and a screen space 3 according to the display commands.
It is composed of a T controller 4 and a CRT display tube 5 that actually displays the display contents of the screen space 3.

The world space 2 stores the entire graphic data drawn according to display commands by the processor 1.

The screen space 3 extracts and stores an arbitrary portion of the graphic data stored in the world space 2, and outputs it to the CRT display tube 5.

The CRT controller 4 includes a command reading section 6 that reads display commands from the processor 1, a world space drawing section 7 that creates graphic data according to the display commands and outputs it to the world space 2, and a screen that displays the coordinate origin of this graphic data. a coordinate origin conversion unit 8 that converts the coordinate origin to the coordinate origin of space 3; a screen space drawing unit 9 that has a clip function and draws graphic data whose coordinate origin has been converted to the screen space 3; It consists of a copy part 10 for extracting graphic data and copying it into the screen space 3.

Next, the operation of this embodiment will be explained with reference to the flowchart shown in FIG.

When a display command is output from processor 1, the CRT
The command reading unit 6 of the controller 4 determines whether this command is a command to change the display position in the world space 2 or a command to newly draw in the world space 2 (step 5Tl).

If the command is to change the display position of world space 2 (YES in step ST1), screen space 3 is once refreshed as before, and then the graphic data of world space 2 whose display position has been changed is copied. (Step 575).

If the command is to draw new display data in the world space 2 (NO in step ST1), the world space drawing unit 7 creates new graphic data and draws it in the world space 2.

At this time, the world space drawing unit 7 determines whether the given command is a command that can be converted into drawing data for the screen space 3 (step 5T3). For example, in the case of a command to fill in a predetermined closed area, the closed area must all fit within the screen space 3 to be filled in. Such a command cannot be converted into drawing data for screen space 3 (No in step ST3), and as before, after drawing in world space 2, the part to be displayed is copied to screen space 3. (Step 5T5).

On the other hand, if the given command is a command that can be converted into drawing data to the screen space 3 (step ST
3: YES), the coordinate origin of the created graphic data is converted into the coordinate origin of the screen space 3 in the coordinate origin conversion unit 8.

Then, the screen space drawing unit 9 creates graphic data to be drawn in the screen space 3 based on the converted coordinate origin and actually draws it (step 5T4).
. At this time, the clipping function of the screen space drawing unit 9 prevents drawing of areas other than those that require drawing.

The graphic data drawn in the screen space is then displayed on the CRT display tube 5.

In this way, in this embodiment, when the command given from the processor 1 is a command that can draw directly on the screen space 3, the coordinate origin of the graphic data created by the world space drawing section 7 is set to the screen space 3.
The graphic data in screen space 3 is converted into the coordinate origin of , and this is directly drawn in screen space 3.

Further, in the screen space drawing section 9, drawing is not performed in areas other than those that require drawing due to the clip function.

Therefore, the time required to draw in the screen space 3 is significantly shortened, and the operability of the system is improved.

[Effects of the Invention] As described above, according to the present invention, newly drawn graphic data is directly drawn in the screen space, so that the copying time from the world space to the screen space can be omitted.

This has the effect of significantly shortening the drawing time in the screen space and improving the operability of the system.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention, FIG. 2 is a flowchart showing the operation of the CRT controller in the embodiment, and FIG. 3 is an explanatory diagram for copying display data from world space to screen space. It is. 2...World space 3...Screen space 4
...CRT controller 6...Command reading section 7...World space drawing section 8...Coordinate origin conversion section 9...Screen space drawing section

Claims (1)

[Claims] In a graphic display system that draws the entire graphic data in a world space and copies a portion of the data to be displayed into a screen space to display the data, there is provided a world space drawing means for drawing the graphic data in the world space. and a coordinate origin conversion means for converting the coordinate origin of the world space to the coordinate origin of the screen space, and a screen space drawing means for directly drawing the graphic data converted to the coordinate origin of the screen space in the screen space. Features a graphic display system.