JPS6279576A - Graphic display device - Google Patents

Abstract

PURPOSE:To obtain the required shape of a graphic form at high speed by providing a window management memory that offers information whether a coordinate is hidden or not with other window when a graphic data defined within every window is processed. CONSTITUTION:A window number 2W2 is set against a latch 12 and the area address of the window number 2W2 is given in order to a RAM7 and a data 2D2 is written only by area share of the window number 2W2. At the next, the latch 12 is updated to a window number 6W6, and similarly, a data 6D6 is written at the area of the window number 6W6, and along with this, to a window management memory 6, a coordinate is given as a read out address 10 having a corresponding resolution, a comparison with the window number being performed. A color code or a luminance code is read out at every regulated cycle at a video interface 4, a D/A conversion being applied on it, and it is displayed on a CRT display 5 as a graphic form. Only the part of the graphic form where is not hidden with the other window is displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a graphic display device that displays a plurality of windows in a superimposed manner, and particularly to an improvement in a superimposition control method for multi-window screens.

[Conventional technology]

FIG. 5 shows a conventional graphic display device of this type. In FIG. 5, (1) is a clipping processor that performs clipping processing of point coordinates using a window.

(2) is a linear generator that performs linear interpolation between the point coordinates given by the clipping processor (1), and (3) is a linear generator that stores the color code or brightness code at the position corresponding to the address output from (2). (4) is a video interface that converts digital information read from the frame buffer memory (3) into analog values and controls display.

(5) is the CRT display.

Figures 6 to 8 are diagrams displayed on the CRT display (5) showing the process of overlapping two windows, with the dashed line showing the outline of the window, and Figure 9 showing the process of overlapping two windows. This shows an overlapping state, and the operation will be explained below with reference to these.

The processing order of graphics in each window is such that the windows located at the back, that is, the windows with the lowest priority are processed first. Therefore, the clipping processor 10 first performs clipping processing on window number 2 (W2), and the linear generator (2) performs clipping processing on the frame buffer memory (W2).
3) by writing to the CRT display (
5) Wind number 2 (w2
) will be displayed.

Next, the clipping processor (1) sends to the straight line generator (2) point coordinates and a colorless code or a zero brightness code for filling out the entire area of window number 6 (W6). This allows frame buffer memory (3)
The contents of the screen have been updated, and the part of the figure with window number 2 (W2) hidden by the area with window number 6 (W6) has been erased on the CR,T display (5) as shown in Figure 7. Is displayed. And after that, wind number 6
A graphic writing process is performed for (w6), and as a result, both sides are displayed in a manner corresponding to the overlapping of the two windows as shown in FIG.

In this example, the case of two windows has been described, but even if there are more windows, overlapping is performed by repeating the above process.

[Problem that the invention seeks to solve]

Since the conventional graphic display device is configured as described above, when multiple windows are superimposed, it is necessary to erase the area of the ninth window before writing the graphic of the ninth window. As shown in the figure, when the areas of each window are thick and overlap with each other with slight deviations, there is a problem in that it takes a very long time to update the two windows.

This invention was made in order to solve this problem, and it is possible to create a graphic that can obtain the desired shape at high speed without affecting the update speed of the graphic due to the difference in the way the windows are overlapped. The purpose is to obtain a display device.

[Failure to solve the problem]

The graphic display device according to the present invention defines the area of each window as
The number is stored as data in order from the lowest rank to the 9th display stage, and when the line generator processes the graphic data defined in each window, it is possible to check whether the coordinates are hidden by other windows or not. It is equipped with a wind management memory that provides information.

[Effect]

In this invention, the final overlapping shape of each window area is stored in the window management memory, and at the time of processing in the linear generator, it is checked whether or not it is necessary to write it to the frame buffer, and the portions hidden by other windows are not stored. Performs control that does not involve any interference.

〔Example〕

FIG. 1 is an overall configuration diagram showing an embodiment of a graphic display device according to the present invention. As is clear from FIG. 1, this embodiment includes a clipping processor 11.1 that clips a point coordinate string of a figure using a given window frame;
A linear generator that performs linear interpolation between point coordinates within the window obtained by clipping processing, and the area of each window.
The numbers are stored as data in order of 9 display priority, starting from the lowest display priority, and when the line generator processes the graphic data defined in each window, information is given as to whether or not the coordinates are hidden by other windows. A window management memo (January 6) to provide It is configured to perform the conversion and display it as a graphic on the CRT display (5).

Figure 2 shows the configuration of the above Wind Management Memo (January 6). In Figure 2, (7) is a RAM with a depth of N bits and a capacity corresponding to the resolution of the window.

N is the number of bits that can represent all window numbers in binary.

(8) is an address selection circuit, and the input address (9)
and read address aO) and select RAM (7
) provides the hair address I. a2 is an N-bit latch that stores a window number, and provides input data to RAM (7) and a window value to comparator Q3. (14 is the match/mismatch output of the comparator α, and the linear generator (2)
given to.

Figure 3 shows an example of the window number written in the wind management memo (January 6), and Figure 4 shows an example of the graphics displayed on the CRT display (5) using this method. The operation will be explained with reference to.

In the case of this embodiment as well, as in the case of the conventional apparatus described above, the processing order of graphics in each window is such that the window located at the back is processed first. Therefore, the clipping processor il+ first starts a window mask memory write operation for window number 2 (w2). First, window number 2 (w2) is set for latch α, and then RAM
The area address of window number 2 (w2) is sequentially given to (7), and the area address of window number 2 (w2) is given to RAM (7).
) area division data 2 (D2) is written.

Next, the latch tL2 is updated to window number 6 (w6), and data 6 (D6) is written in the area of window number 6 (W6) using the same procedure, resulting in the state shown in FIG. 3. At this time, other areas that have not been written to have data O(D) because they are first cleared to zero.

After the above operation, the window number 2 (W2) to be processed first is set in latch a, and the window number 2 (W2)
The point coordinates of the figure are sent to the straight line generator (2) and the coordinates are sequentially generated. In parallel with this, in the Wind Management Memo January 6), the above coordinate values are given as a read address QO) with a corresponding resolution, and RAM (7)
The comparator a3 compares the data read from the latched window number with the latched window number. Then, a match/mismatch signal a< is given from the comparator 03 to the linear generator (2). Linear generator (2).

If this signal a4 matches, the frame buffer memory (
3), and if they do not match, the write operation is not performed because it is hidden by another window.

The color code or brightness code thus stored in the frame buffer memory (3) is read out at regular intervals by the video interface (4), subjected to D/A conversion, and displayed on the CRT display (5). Cab.

Displayed as a shape. Unlike conventional figures, only the parts of this figure that are not hidden by other windows are displayed.

After all the graphic data for window number 2 (w2) is processed, latch a2 is updated to window number 6 (W6), and the graphic data for window number a (W6) is processed in the same way.

After processing all the graphic data in this way, C
The figure shown in Fig. 4 is displayed on the RT display (5), and the shape that is finally required is displayed without having to erase the window area once for each window processing unit, which was done in the conventional method. It has the advantage that the figure can be obtained very quickly, and the difference in how the windows overlap does not affect the update speed of the figure.

In the above embodiment, the comparison results are determined using a linear generator (
2) I explained what to do.

A similar effect can be expected by using a frame buffer memo (January 3). Furthermore, although the window frame is rectangular in the embodiment, similar effects can be obtained with any shape.

Furthermore, the effect can be further increased by quantizing the resolution of the wind management memory.

〔Effect of the invention〕

As explained above, according to the present invention, the areas of each window are sequentially stored in order of 9 display priority, using the number as data, and the linear generator processes the graphic data defined in each window. Wind management memory provides information about when its coordinates are hidden by other windows, so parts of the shape that are hidden by other windows are not displayed, therefore.

The process of erasing the window area, which was conventionally performed for each window processing unit, is no longer necessary.

For this reason, a figure of the final required shape can be obtained at high speed, and differences in the way windows are overlapped do not affect the update speed of the figure.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a graphic display device according to the present invention, FIG. 2 is a block diagram showing the configuration of a wind management memory, and FIG. 3 is an example of window numbers written in the wind management memory. FIG. 4 is an explanatory diagram showing the final figure displayed on a CRT display using this method. FIG. 5 is a configuration diagram showing a conventional graphic display device. FIGS. 6 to 8 are diagrams showing the conventional device. An explanatory diagram of display figures on the C'RT display showing the processing process when overlapping two windows in , No. 9
The figure is an explanatory diagram showing a display figure on a CRT display when a large number of windows are overlapped with each other by shifting them little by little in a conventional device. (1)... Clipping processor, (2)... Straight line generator. (3)...Frame buffer memory, (4)...Video interface, (5)...CRT display, (6)...Window management memory Note that the same reference numerals in each figure are the same or equivalent. shall indicate the part.

Claims (1)

[Claims] A clipping processor that clips a point coordinate string of a figure using a given window frame; a linear generator that performs linear interpolation between the point coordinates within the window obtained by the clipping process; A device that displays multiple windows in a superimposed manner, comprising a frame buffer memory that stores a color code or a brightness code at a coordinate position, and a video interface that reads the code from the frame buffer memory and displays it as a figure on a display, A graphic display device comprising a window management memory that stores the weight status of each window.