JPS6312077A - Grid description system - Google Patents

Abstract

PURPOSE:To reduce the number of times of multiplication and division required for calculation of the address and the bit position of each grid by making data, which is related with respective addresses of all coordinates, resident on a general memory. CONSTITUTION:All addresses on a picture memory of (x) coordinates in a first column in the (y) direction are calculated by a central processing part 1 and are written in a general memory 2. Bit positions on a picture memory 3 are calculated with respect to individual (x) coordinates and are written in the general memory 2. Next, addresses of (y) coordinates stored in the general memory 2 are read out to calculate addresses on the picture memory 3 with respect to (y) coordinates, and addresses of (x) coordinates stored in the general memory 2 are read out and are added to addresses of (y) coordinates. Thereafter, bit position data in the general memory 2 is written in addresses of the picture memory 3. Consequently, data written in the picture memory 3 can be described on a display device 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a grid drawing method that can draw a grid on a display at high speed.

[Conventional technology]

Normally, the grid drawing method for drawing a grid on a display takes the bottom left as the origin and draws the first column in the y direction as the starting address a of the image memory, then sequentially moves upward to the second column, The third column is for drawing...

FIG. 4 is a flowchart showing a conventional grid drawing method. First, in step SI, the y coordinate of the grid to be drawn is calculated. Next, in step S, the X coordinate is calculated.

Next, in step S3 and step S4, the address and bit position on the image memory are calculated from the values of the X and Y coordinates. Next, in step S5, data is written to the image memory at this calculated address. Then, in step S6, it is determined whether or not the right end of the current column has been drawn. If the right end has not been drawn, steps S to S5 are repeated. Step S if the current column is finished? After recalculating the y-coordinate of the next column of levers, the steps S and -Ss are repeated again. Then, if the last row has been completed, drawing ends. In this way, the coordinates are calculated by calculating the y-coordinate n times for each grid and the x-coordinate m times for each column, and the drawing data can be written into the image memory.

[Problem that the invention seeks to solve]

The conventional grid drawing method described above requires n calculations of the y coordinate and m calculations of the two coordinates for each column.
Requires multiple multiplications. Furthermore, the process of determining the address value of the image memory is required (mXn) times. Therefore, there is a problem in that it takes time on the order of seconds to finish drawing all the grids, and that efficiency and operability are poor when performing screen operations.

[Means for solving problems]

The five-grid drawing method of the present invention is such that data relating to all addresses of coordinates representing each position of the grid resides in a general-purpose memory and is used when writing to the image memory.

[Effect]

The invention can reduce the number of multiplications and divisions required to calculate the address and bit position of each coordinate of the grid.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the grid drawing method according to the present invention. In the figure, 1 is a central processing unit (CPU), 2 is a general-purpose memory, 3 is an image memory, 4 is a controller, and 5 is a display. Next, the operation of the grid drawing method with the above configuration will be explained using the flowchart shown in FIG. First, in step SL,
The central processing unit 1 calculates all addresses on the image memory of the X coordinate of the first column in the υy direction. Next, step S!
Then, write this calculated X-coordinate address into general-purpose memory 2. Next, in step S, the bit position on the image memory 3 is calculated for each of the X coordinates. Next K,
In step S4, the calculated bit position on the image memory 3 is written into the general-purpose memory 2. Next, in step S, the address of the y-coordinate stored on this general-purpose memory 2 is read out, and the address on the image memory 3 for the y-coordinate is calculated. Next, in step S, the x-coordinate address stored on the general-purpose memory 2 is read out, and the y-coordinate address is added. Next, in step S, the bit position data on the general-purpose memory 2 is written to the address on the image memory 3. Thereby, the data omitted on the image memory 3 can be drawn on the display 5.

〔Effect of the invention〕

As explained in detail above, according to the grid drawing method according to the present invention, data regarding all addresses of each coordinate is resident in a general-purpose memory, and the multiplication and Since the number of divisions can be reduced, there is an effect that grid drawing on the display can be processed at high speed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the grid drawing method according to the present invention, FIG. 2 is a flowchart showing the operating procedure of FIG. 1, FIG. 3 is a diagram showing the correspondence between the screen and image memory, and FIG. The figure is a flowchart showing the operation procedure of the conventional grid drawing method. 1...Central processing unit, 2...General purpose memory, 3...Image memory, 4...
Controller, 5...Display.

Claims (1)

[Claims] The present invention is characterized in that data regarding the address and bit position of the image memory calculated from the coordinate data representing the position of the grid is generated on a general-purpose memory, and this data is used as information for address calculation when writing to the image memory. Grid drawing method.