JP2917684B2 - Window display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a window display device, and more particularly to a window display device for displaying a plurality of windows on one display screen.

[0002]

2. Description of the Related Art A so-called multi-window technique for displaying a plurality of windows on a display screen has been adopted and widely used in engineering workstations (EWS) and personal computers (PC). this is,
Since the processing capabilities of these devices have been dramatically improved with higher performance of CPUs, it is possible to provide a processing environment such as multitasking and multiuser, and inevitably reduce the processing status of each task by one. This technology was devised because it became necessary to simultaneously display on two screens.

[0003] Each window is generally rectangular, and the position, size, and display priority in the XY coordinate space mapped on the screen are managed as parameters. For example, with the upper left of the screen as the origin of the coordinate space, "the position of (100, 100) with the XY coordinates is the upper left point of the rectangle, the width is 100, the height is 50, and the display priority is the first place"
Define a window with such information. The method adopted in the EWS and the PC is a so-called software window technology as shown below.

[0004] According to the software window, characters and figures are drawn so as not to protrude from windows assigned to individual tasks. That is, it is checked in advance whether the character / graphic to be drawn by the above task is (1) fit within the window, (2) straddles the boundary, or (3) is out of the window. Draw,
In the case of (2), the boundary is detected and only the portion within the window is drawn, and in the case of (3), it is ignored. If a plurality of windows are nested, the window is divided into small rectangular areas, and the above processing is repeated. That is, when the display content in the window is changed or when the window position is changed, the corresponding rectangular area is redrawn. In a standard window system such as X-Windows and MS-Windows, in order to increase the processing speed of a window, a surface hidden by another window is saved as a bit image, and an operation of reappearing the bit image is performed. At this point, high-speed processing, such as restoring the contents of the bit image saved at a time, is applied, and this is called software window technology.

Some devices employ hardware window technology for software windows. A typical example is a game machine. Characters (graphics) and backgrounds that move vertically and horizontally on the screen are each drawn in a specific memory area. When sending display data from the window system to the display, the data in which memory area is read. Dynamic selection of dashi. That is, by switching the display address, the graphics and backgrounds stored separately in the memory are combined on one display.

The advantages and disadvantages of each window technology will be described. The advantages of a software window are that there is no limit on the size, number, or overlap of the windows. Of course, when the number of windows is large or the degree of overlap is complicated, the processing time is long, but it is flexible enough to withstand any application.

On the other hand, the advantage of the hardware window is that
The display is fast. Display screen is generally 1
It is refreshed every / 60 seconds, but the position and size of the window can be changed within this short time. Therefore, it is an indispensable technology for a gaming machine that emphasizes high speed and responsiveness of the screen. The disadvantages are that the number, size, and degree of overlap of the windows are limited, and the memory area for storing image data displayed in each window becomes enormous. The limitation on the number of windows is the number of windows that can be displayed on one line. This is because the address on the memory to be displayed must be calculated from the display position and the display priority, and the window switching must be completed in real time, that is, by the time the previous window is completely displayed.

Conventionally, in an EWS or PC environment, high-speed performance in window display as in a game machine is not required due to its use. Instead, software windows that could withstand any application were accepted. However, recently, multimedia workstations, multimedia personal computers, and the like that can display moving images on a window have attracted attention, and it has become essential to display moving images in real time.
In this case, it is impossible only by the software window method, and the hardware window technology must be adopted. Here, real time means that new data is displayed within 1/60 seconds, which is the refresh rate of the display. However, when the hardware window method is used, a large amount of memory capacity is generally required because data to be displayed needs to be once stored in a memory. Especially the video is RGB
(Red. Green, Blue) In many cases, the image is displayed in a so-called full color of 8 bits each. At the maximum, the image is displayed on the entire screen. If this is the case, there is a problem that a memory of about 30 Mbits is required and becomes very expensive.

[0009]

In the above-described conventional window display device, when a hardware window system capable of real-time display of a moving image is used for high-resolution display, image data to be displayed is stored in a memory. However, there is a drawback that a huge amount of memory capacity is required and the cost is extremely high.

[0010]

A window display device according to the present invention sets at least one window which is a predetermined processing area on a display screen, displays and processes a predetermined image in the window, and processes the window. in the display position and window display device having a memory in which the display target data is stored, the display from the window information including storing an address display address of the display position and the display target data of the window in the memory
The address information of the address and the window
The horizontal position of the switching point of the display position
A window containing the X number of pixels and the Y coordinate value of the number of lines
Window list generating means for generating a window list;
The number of display lines, which is the number of scanning lines displayed on the display screen
Is counted and the current line, which is currently displayed, is
A line counting means for outputting a corresponding current line value;
The number of pixels in the horizontal direction displayed on the display screen is counted and displayed.
A pixel counting means for outputting a display pixel value, and the display address
Address calculating means for calculating the display address;
Address updating means for updating lines, and the window
At least one line in the current line of the list
To store the current line list that is
Line list storage means, and the current line value
Compare with the Y coordinate value in the window list and match
The current line list to the current line
Window list transferer to transfer to in-list storage
Step, the display pixel value and the window list
Compare with the X coordinate value and calculate the address if they do not match
Means to calculate the display address, and when they match,
Of the next window in the current line list
With reference to the second window information, the address calculation means
Change the display address to be calculated and
Address for changing the address information in the
And an address change means .

[0011]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of the window display device of the present invention.

As shown in FIG. 1, the window display device according to the present embodiment has, from the window information, the address information of the display address and the horizontal pixel at the switching point of the display position where the window is switched to the next window. The window list generation unit 1 that generates a window list including the number X and the number of lines Y coordinate, and the window list from the window list generation unit 1 and the number of lines from the line counting unit 3 are compared and matched. A window list transfer unit 2 for transferring data in a case, a line counting unit 3 for outputting display line number data, a current line list storage unit 4 for storing a current line list which is data of a line currently displayed, and updating an address. Address updating unit 5 which adds the immediately preceding address and the pitch to the address in the current address list. An address change unit 6 to change the broadcast,
It comprises a pixel counting section 7 for counting the number of display pixels in the horizontal direction of the line currently being displayed, an address calculation section 8 having a register for storing a display address, and a memory section 9.

Prior to the description of the operation, a definition of a window and a window list will be described. FIG. 2A shows a window definition in this embodiment, and FIG. 2B shows an address on the memory 9 where display data is stored, and FIG. 2B shows a window display position (diagonal coordinates of a rectangular area). For example, the display position of the window A is such that the upper left coordinate is (XAS, YAS) and the lower right coordinate is (XAE, YAE)
It is assumed that the address on the memory 9 where the data to be displayed is stored is the address A.
Using the parameters defined here as an input, the window list generation unit 1 creates a window list. Table 1 shows some examples of the contents of the window list corresponding to the example of FIG.

[0014]

[Table 1]

As shown in Table 1, a table is created on the basis of the line on which the display content of the window changes.
The information of each line includes information of all window change points on the line, with the Y coordinate change point as a header and the start X coordinate and the display start address as a pair.
The first row of Table 1 is a list of the first line of the display, that is, the Y coordinate is “0”, and the X coordinate is “0”, that is, the display address of the left end of the display is “address D”.
The X coordinate indicates "1280", that is, the display is continuously performed to the right end of the display. The data displayed here is the window D, that is, the background that covers the entire screen. This display state continues until the display line has the same value as the Y coordinate “YCS” shown in the second line. When the display line becomes “YCS”, the display is started from the address of “address D + YAS × pitch” in window D. When the display X coordinate becomes “XAS”, the window is switched to window C,
The display address is set to “address C”. Further, when the X coordinate becomes “XCE”, the window D is returned to the window D again, and the “address D + YCS × pitch + XCE” is returned to the window D.
Resume the display of. Although the display start address in Table 1 is described by a mathematical expression for convenience, the numerical value after the calculation is actually stored.

Such a window list may be generated when there is a change in the window display. Even if the window is a complicated one with a slightly nested window, the window list can be generated within 1/60 second of one frame display time. Processing is performed by software as long as it can be processed. Since the window information of each line is of variable length, the head addresses where the information of each line is stored are created together in a table so that the information of each line can be accessed by specifying an indirect address. Although this is intended to reduce the storage area of the window list, it is a commonly used technique, and a detailed description thereof will be omitted.

Next, how a window list is input and how window control is performed will be described. FIG.
The flow of the process will be described in accordance with FIG.

First, the Y coordinate stored in the window list 1 is compared with the number of lines of the line counting unit 3. If they match, all the data related to the line in the window list 1 is transferred to the current line list storage 4. In the present embodiment, the current line list storage unit 4 stores the Y coordinate change point at 16 bits and the X coordinate of the X coordinate change point at 1 bit.
6 bits, display start address is 32 bits and 16 X
Up to the coordinate change point can be stored. This operation is controlled by the window list transfer unit 2. Also,
This operation is performed before the timing of actually displaying the line, that is, in a so-called horizontal retrace period. Although not shown, the operation sequence is basically controlled in synchronization with a display synchronization signal supplied from outside, that is, a vertical synchronization signal and a horizontal synchronization signal. Next, the X coordinate of the current line list from the current line list storage unit 4 is compared with the number of pixels of the pixel counting unit 7. If they match, the address information of the current line list stored as a pair with the X coordinate is read, and the address information is stored in a register included in the address calculation unit 8. The contents of the register of the address calculation unit 8 are output to the memory unit 9 as a display address. At the same time, the address change unit 6 adds the address and the pitch used until immediately before, and rewrites the address information in the current line list. These operations are repeated until the pixel counter 7 detects that the number of pixels for one line is displayed.

When the display of one line is completed, the line counting unit 3 adds "1" to the number of lines, compares the number with the Y coordinate of the current line list, and if there is a match, repeats the above processing. In this case, the above-described processing for one line is repeated without changing the current line list. This is because the contents of the current line list are sequentially changed to the data for the next line while the display processing of a certain line is being performed. Is already completed during the processing of the previous line. The output display address is input to the memory unit, and desired window data is read and displayed. Thus, the window information stored in the memory 9 is displayed at a desired position on the screen.

Next, a second embodiment of the present invention will be described. FIG. 3 is a block diagram of a second embodiment of the present invention.
3, the difference from the first embodiment shown in FIG.
A display data selection unit 10 which is a control mechanism for selecting one of the display data read from the memory 9 and another moving image data and supplying the selected data to the display;
0 to 23 are added so that a moving image window can be displayed in addition to the first embodiment. Therefore, the basic operation is the same as in the first embodiment. The window identification numbers shown in FIG. 4 are added to the window list.

Next, the operation of this embodiment will be described.
The display address output from the address calculation unit 8 is input to the memory unit 9, and the read data and the four data outputs output from the moving image data generation units 20 to 23 are input to the display data selection unit 10. The window identification number is also output in synchronization with the output timing of the display address. As shown in FIG. 4, the window identification number is stored as a pair with the X coordinate and the display address in the window list. This identification information is transferred to the current line list storage unit 4 in the same manner as the other information, and is continuously output until the next window area is reached due to the match of the X coordinate comparison. Therefore, the number of the currently displayed window can be output to the display data selection unit 10 in real time. Video data generator 2 that supplies video data
Nos. 0 to 23 supply display data to be displayed in synchronization with a horizontal / vertical synchronization signal of the display in accordance with a screen position to be displayed.

The display data selection unit 10 uses this window identification number to generate the moving image data generation units 20 to 2
3 and display data output from the memory unit 9 are multiplexed. The display data selection unit 10 includes a register for storing four moving image window numbers, four comparison circuits, and a 5-to-1 multiplexer. Window identification number output from current line list storage unit 4 and moving image data generation unit 2
The window numbers 0 to 23 are individually compared with each other by four comparison circuits, and if they match, the display data output from the matching moving image data generation unit is selected and output to the display. If it does not match any of the window numbers of the moving image data generation units 20 to 23, the data output from the memory unit 9 is selected.

As described above, moving image data can be correctly displayed even if the shape is partially hidden by another window, for example, the area of the window B in FIG. .

As described above, the window display device of the present invention can delete the memory for storing moving image data other than the memory for normal window display, thereby greatly reducing the required memory capacity. Can be. For example, assuming that moving images are displayed on four screens, the required capacity of the above-mentioned normal window display memory is about 10M for 256-color display.
Since the required capacity of the moving image memory is about 30 Mbits per plane as described in the conventional example, the memory for about 120 Mbits can be reduced for four planes.
That is, the cost of the memory can be reduced to 1/13. In addition, the required memory capacity increases in proportion to the number of moving image windows in the conventional method, but is independent of the number of moving image windows in the present invention.
The effect on cost reduction is even greater.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made.

For example, although the number of moving images is four in the embodiment, the number of windows that can be displayed is determined by the number of hardware on the side that supplies moving image data, and is limited by the window control device of the present invention. is not. Therefore, a system capable of displaying an arbitrary number of windows can be easily constructed by adding moving image data supply hardware. Moreover, what needs to be added on the side of the window control device according to the number of window surfaces is only the window identification number comparison circuit and the display data selection circuit of the display data selection section. There is no change in the main part of the display address generation.

In the first embodiment, the contents to be displayed are all stored in the memory. However, even if the display data is supplied directly from a video system or the like as shown in the second embodiment, the display is not performed. Since data can be multiplexed at the last stage, it is easy to add moving image hardware in terms of hardware. Further, even when the hardware window of the present invention is realized, the conventional software window can be used without deteriorating the functions and performance at all.

In this embodiment, the width of the memory area storing the display data of each window is set to a constant value.
By adding the memory area width of each window to the window list and using the memory area width read from the window list when adding a pitch by the address changing unit, a more flexible display data memory configuration can be achieved. realizable. Also, the maximum number of X change points that can be stored in the current line list storage unit is 16,
The window change point on one line was limited to 16, but this can be easily increased by adding hardware. Also, the number of bits of each window information may be an arbitrary value, and is not fixed to the number of bits defined in the present embodiment.

[0029]

As described above, in the window display device of the present invention, the update speed of the window is improved by the hardware control, and the memory for storing moving image data other than the memory for normal window display is deleted. Therefore, the required memory capacity can be significantly reduced, and the cost can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a window display device of the present invention.

FIG. 2 is a diagram illustrating an example of a definition of a window.

FIG. 3 is a block diagram showing a second embodiment of the window display device of the present invention.

FIG. 4 is a block diagram showing an example of a conventional window display device.

[Explanation of symbols]

 Reference Signs List 1 window list generation unit 2 window list transfer unit 3 line counting unit 4 current line list storage unit 5 address updating unit 6 address changing unit 7 pixel counting unit 8 address calculation unit 9 memory unit 10 display data selection unit 20 to 23 movie data generation Department

Claims (2)

(57) [Claims] 1. A predetermined processing area on a display screen.
Set at least one window and within said window
Display and process a predetermined image in the
Memory that stores the display position and display target data.
Display position and display of the window in the memory
C containing the display address that is the storage address of the target data
Window informationFrom the address information of the display address and
Display where the window is the point at which it switches to the next window
X, which is the number of pixels in the horizontal direction at the position switching point, and the number of lines
To generate a window list containing the Y coordinate values
Window list generating means; The number of display lines, which is the number of scanning lines displayed on the display screen
Is counted and the current line, which is currently displayed, is
A line counting means for outputting a corresponding current line value; The number of pixels in the horizontal direction displayed on the display screen is counted and displayed.
A pixel counting unit that outputs a pixel value, Address calculating means for calculating the display address; Address updating means for updating the display address by one line
Steps and A small number in the current line of the window list
Current line list that is information of at least one line
Current line list storage means for storing The current line value and the
The current line is compared with the Y coordinate value,
Transfer the list to the current line list storage means
Window list transfer means; The display pixel value and the X coordinate in the window list
The address is calculated by comparing the
The display address is calculated from the
The second window of the next window in the rent line list
The address is calculated by the address calculating means with reference to the window information.
Change the display address
An address change that changes the address information in the inlist
Further measures Window display device characterized by comprising:
Place. Wherein said window information includes an identification number of the window, the display address to the identification number and have based Dzu the first from the memory display data and the outside from the second output synchronously 2. The window display device according to claim 1, further comprising display data selection means for selecting one of the display data.