JPH087554B2 - Rewriting method of display color in bitmap type color display device - Google Patents

Description

DETAILED DESCRIPTION [Overview] A method of rewriting a plurality of display colors at high speed and efficiently only by controlling planes. Two display colors in an arbitrary region can be changed to a desired color at high speed and efficiently. For the purpose of rewriting, it has an old display color designating section for storing two old display colors and a new display color designating section for storing two new display colors, and the control means has the new display color. The bit corresponding to each plane is inspected with respect to the data of the new display color stored in the designating section, a predetermined computation is set in the computing means of each plane, and the result is stored in the old display color designating section. The two old display color data are compared with each other, a plane having different bits is selected, and the pixel data of the plane is transferred to the arithmetic means of each plane to change the pixel data.

[Industrial applications]

The present invention relates to a method of rewriting a display color in a bitmap type color display device, and more particularly to a method of rewriting a plurality of display colors at high speed and efficiently only by controlling a plane.

In recent years, with the rapid progress of data processing using electronic calculators, increasingly sophisticated and high-speed functions are required for presenting the processing results. For example, even in the display of a cursor that is moved by a mouse or the like, the high-intensity display or the reverse display has advanced to the one-color display or the two-color display.

[Conventional technology]

Conventionally, when rewriting the display color of a specific part on the display screen of a CRT, which is a display device, the part to be rewritten is used as a clip frame and the displayed data is redrawn while the displayed characters and figures are redrawn. Then, it is checked whether or not those characters, figures, etc. are within the clip frame, and if they are within the clip frame, redrawing is performed by rewriting the display color by changing the color designation.

[Problems to be Solved by the Invention]

However, the above conventional technique has the following two problems.

-It takes a lot of time to display and delete, and the response of the cursor etc. is bad.

-It is necessary to save all display data displayed on the CRT for redrawing, resulting in inefficient use of memory.

For these reasons, conventionally, the operation of the application program has been slow, which is inconvenient for the user.

The present invention was devised in view of such problems, and it is possible to rewrite a display color in an arbitrary region to a desired color at high speed and efficiently, and to display a display color in a bitmap type color display device. The purpose is to provide a rewriting method.

[Means for solving the problem]

In order to achieve the above object, a display color rewriting method in a bitmap type color display device of the present invention uses a frame memory for storing pixel data and a logical operation on the pixel data, and the result is used as new pixel data. A plurality of planes each having an arithmetic means for storing in each position, a writing means for at least the pixel data to the frame memory, and a control means for controlling the arithmetic means, and one pixel arranged on each plane. A bit map type color display device that expresses the color of the pixel by a bit pattern of the data, and an old display color designation unit that stores two old display colors and a new display color that stores two new display colors. A new display color data stored in the new display color specification unit. Then, the bit corresponding to each plane is inspected, a predetermined operation is set in the operation means of each plane based on the result, and the data of the two old display colors stored in the old display color designating section is further set. In contrast,
A plane having different bits is selected, and the pixel data of the plane is transferred to the arithmetic means of each plane to change the pixel data.

[Action]

According to the present invention, by providing two old display color designating parts and a new display color designating part and controlling by paying attention to the relationship of the respective pit patterns, it is possible to perform arbitrary control without referring to all the display data displayed on the CRT. The two old display colors in the area are rewritten to the designated new display color in pixel units.

For example, FIG. 4 shows a case where the display color of 1 pixel is represented by 4 bits, and is an example of a bit pattern of new and old display colors set in each display color designating section. It is shown. Looking at the bit pattern in this way, it can be seen that there is a specific relationship between the old display color and the new display color in each plane. That is, in the example of FIG. 4, in plane 0, the new display color is always "0", in planes 1 and 2, the new display color is equal to the old display color, and plane 3
Then, the new display color is always "1". Further, in planes 0 and 3, it may be considered that the new display color is equal to the old display color inverted.

Therefore, in order to convert the original pixel data for each plane into the bits of the new display color, the respective calculation means should always output “0” or “1” according to the above relation, or input Is set as it is, or inverted, and output. For the original pixel data, planes having different bits are selected so that the two old display colors can be distinguished, and the Vixel data at a desired position in the original pixel data is transferred to the arithmetic means of each plane to cause each plane to perform arithmetic operation. By creating new pixel data, each plane can be converted into bits of the new display color corresponding to the two old display colors. As a result, the desired two colors can be rewritten simultaneously and at high speed.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a bitmap type color display device according to an embodiment of the present invention. In the figure,
Reference numeral 11 is a CPU (central processing unit) which is a control means, 12 is a main memory for storing programs and display data of the CPU 11, 13
Is a CPU bus, 14 is a bitmap part for storing pixel data, 15 is a CRT which is a color display device, 16 and 17 are old display color designation parts for storing two old display colors, and 16 is the old display color 1 Register 17 is the old display color 2 register.
Reference numerals 18 and 19 are new display color designation sections for storing two new display colors, 18 is a new display color 1 register, and 19 is a new display color 2 register. The display on the CRT 15 is performed by the CPU 11 by creating pixel data from display data such as characters and figures stored in the main memory 12 and writing the pixel data in the bitmap unit 14.

FIG. 2 is a detailed configuration diagram of the bitmap unit 14 in the above configuration. As shown in FIG.
Determines the display color of one pixel displayed on the CRT15,
4 planes 0, 1, 2, 3 that store each bit of pixel data consisting of 4 bits, and 1 pixel value consisting of 4 bits read from each plane are converted into RGB to CRT15.
It is composed of a LUT (look-up table) 21 for converting into a value and a bit map bus 22 for connecting between plays. The planes 0, 1, 2, 3 are connected to the CPU bus 13 so that the CPU 11 can access each plane. As described above, in this embodiment, the display of 16 colors is enabled by configuring the four planes, and the CPU 1
In 1 the pixel data, the LSB bit of which is plane 0
The MSB bit is arranged in plane 3 and the display color is designated by the bit pattern.

FIG. 3 is a detailed configuration diagram of planes in the above configuration. Each plane has a frame memory 31 for storing pixel data, a read register 32 for holding data read from the frame memory 31, and old pixel data. It is composed of an arithmetic unit 33, which is an arithmetic means for performing a logical operation and storing the result as new pixel data at the original position. In the figure, a dotted arrow indicates the flow of control data sent from the CPU 11 via the CPU bus 13, and a solid arrow indicates the flow of pixel data.
Pixel data is read from the frame memory 31 to the LUT 21 at any time. Further, under the control of the CPU 11, the read register 32 reads the pixel data at the specified position from the frame memory 31 and sends it to the bitmap bus 22. The arithmetic unit 33 is also set with a logical operation under the control of the CPU 11, reads data from the bit map bus 22, performs an operation, and stores it in the frame memory 31 as new pixel data.

Next, the operation of the CPU 11 in rewriting the display color of this embodiment will be described with reference to FIGS. 4 and 5. FIG. 4 is an example of a bit pattern of an old display color and a new display color for rewriting, in which the plane number corresponding to each bit is shown in the uppermost row. FIG. 5 is an explanatory diagram of the operation of each plane in the example shown in FIG. For simplification of description, it is assumed that the display color is rewritten on a pixel-by-pixel basis.

1) First, set the pixel data of two display colors that are displayed on the CRT 15 and that are desired to be rewritten in the old display color 1 register 16 and the old display color 2 register 17, and then set the old display color 1
The new display color to be rewritten for the new display color 1 register 18,
The new display color for the old display color 2 is set in the new display color 2 register 19, respectively.

2) Check the contents of the new display colors 1 and 2 for each bit corresponding to each plane, and set one of the following four operations to the arithmetic unit of each plane.

New display color 1 = New display color 2 = 0 X = 0 New display color 1 = New display color 2 = 1 X = 1 New display color 1 = 0, New display color 2 = 1 X = * B New display If color 1 = 1 and new display color 2 = 0, X = B where X is the output of the arithmetic unit, that is, new pixel data, B is data on the bitmap, and * is inversion. In the example of FIG. 4, the operation shown in the “Operation” column shown in FIG. 5 is set in the operation unit of each plane.

3) Compare the contents of the old display colors 1 and 2, and select the plane having the old display color 1 = 1 and the old display color 2 = 0 as the condition of different bits. In the example of FIG. 4, it is plane 1.

4) Pixel data at a desired position in the plane selected in 3) is read into the read register 32 and sent to the bitmap bus 22.

(If the read position is a pixel of old display color 1,
“1” is sent to the bit map bus 22 and “0” is sent to the bit map bus 22 if the pixel has the old display color 2. ) 5) Operate the arithmetic unit of each plane to write new pixel data to the frame memory.

6) Pixels in the rewriting range 4), 5)
Repeat the operation of.

If the condition of the old display color in 3) does not exist, the plane in which the old display color 1 = 0 and the old display color 2 = 1 is selected, and the calculation in 2) is set to “X = B”. The calculation in is changed to “X = * B”.

As described above, in the present embodiment, the bits corresponding to the planes of the two new display colors are inspected, the arithmetic unit of each plane is set, and the planes having different bits of the two old display colors are selected. The display color is rewritten by converting the pixel data at the desired position in the selected plane into new pixel data by the arithmetic unit of each plane.

In the above embodiment, the example in which the display color is represented by four planes has been shown, but it is obvious that the present invention can be made regardless of the number of planes.

[Effects of the Invention] As described above, according to the present invention, since it is not necessary to perform redrawing using display data, it is not necessary to provide a memory for storing the display data after displaying once. Also, for each plane, since the rewriting is performed only by performing an appropriate calculation on the original pixel data at the desired position, the display color in any area can be changed to the desired color at high speed.
Further, it is possible to provide a display color rewriting method in a bitmap type color display device capable of rewriting efficiently.

[Brief description of drawings]

 FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, FIG. 2 is a configuration diagram of a bitmap portion, FIG. 3 is a configuration diagram of a plane of the bitmap portion, and FIG. 4 is an old display color and a new display color. FIG. 5 is an explanatory diagram of the operation of each plane. 0 to 3; plane, 11; CPU (control means), 12; main memory, 13; CPU bus, 14; bitmap part, 15; CRT, 16; old display color 1 register, 17; old display color 2 register, 18: New display color 1 register, 19: New display color 2 register, 21; LUT, 22; Bit map bus, 31; Frame memory, 32; Read register, 33; Arithmetic unit (arithmetic means).

Claims (1)

[Claims] 1. A plurality of frame memories (31) for storing Vixel data and arithmetic means (33) for performing a logical operation on the pixel data and storing the result at the original position as new pixel data. Each plane (0-3) includes a plane (0-3) and a control means (11) for at least writing pixel data to the frame memory (31) and controlling the arithmetic means (33). A bit map type color display device for expressing a color of a pixel by a bit pattern of data of one pixel arranged in an old display color designating unit (16, 17) for storing two old display colors.
And a new display color designation section (18,1) that stores two new display colors
9), and the control means (11) further comprises the new display color designating section (1
Bits corresponding to the respective planes (0 to 3) are inspected for the data of the new display color stored in (8, 19), and the calculation means (33) of the respective planes (0 to 3) is inspected according to the result. 2 is stored in the old display color designating section (16, 17).
Comparing the data of the two old display colors, selecting a plane having different bits, transferring the pixel data of the plane to the arithmetic means (33) of each of the planes (0 to 3), and changing the pixel data. A method for rewriting the display color of a bitmap type color display device characterized by the above.