JPS6292077A - Pattern generating system - Google Patents

Abstract

PURPOSE:To process the dot display of a segment at a high speed by providing a continuous dot number deciding part, a correcting space deciding part and a pattern setting part which perform each prescribed processing respectively. CONSTITUTION:When an indication of display designating the positions of both end dots of a segment is supplied from an input device 2, a continuous dot number deciding part 4 obtains the vertical and horizontal distances between two points. Then the larger one of both distances is defined as the 1st dot number with the other defined as the 2nd dot number respectively. Then the quotient and the residue are obtained after the 1st dot number is divided by the 2nd dot number. This obtained quotient is stored as the continuous dot number. A correcting space deciding part 5 divides the 1st dot number by said residue to obtain the quotient and stores this as a correcting space. A pattern setting part 6 distributes successively the patterns containing the dots arrayed horizontally or vertically according to the horizontal or vertical distance of the continuous dot number. Thus a segment is displayed at a high speed.

Description

[Detailed Description of the Invention] [(Already required)] 1. A dot pattern generation method that approximates a line segment in graphic display processing. I decided to approximate a line segment using a pattern in which the quotient of the larger distance is the number of consecutive dots in the horizontal or vertical direction, and for each number of quotients of the smaller distance divided by the remainder, Correction is made by placing a pattern with one more dot than the pattern.This method eliminates the need to calculate approximate points on a line segment point by point, speeding up the pattern generation process.

[Industrial application field]

The present invention provides graphical display processing for an information processing system.
This invention relates to a method of generating a pattern (1) that approximates a line segment.

In a graphic display device such as a so-called CR'r display device, it is possible to approximate straight lines, curves, etc. of a graphic using only dots (called dots) displayed at a number of fixed display positions on the display device. The display method is generally widely used.

In that case, to display a figure such as a line segment, calculate the dot position closest to the line segment, etc., and dot each F) 1
- It is generally necessary to determine the position.

[Prior art and problems to be solved by the invention] Line segment display processing usually involves specifying dot positions at both ends of the line segment in some way, and then approximating the line segment to connect those dots. The process is to determine the

The display surface is usually controlled as a Cartesian coordinate space with only displayable dot positions as valid points, and each dot has coordinates (
x, y).

When displaying a line segment given both ends (x+, yl) and (xz, yz), ×, ≠ × 2 and yl f=
In the general case of 31z (not a vertical line or a horizontal line), the slope Δy/ΔX of the line segment is determined from this coordinate value.

In the case of −1≦Δy/ΔX≦1, for example, the X coordinate is
Increase by 1 from x2 to each XF! The Y coordinate value on the true line segment for the i reference value is calculated using Δy/ΔX.

Since this Y coordinate value does not match the dot position at -C, the Y coordinate value of the dot closest to the line segment is obtained, for example, by rounding off to the nearest whole number.

In the case of Δy/ΔX>1 or -1>Δy/ΔX, the approximate line segment figure generally requires dots with the same X coordinate value, so contrary to the above, for each Y coordinate, X
I need to find the coordinates.

According to the conventional method described above, the Y or X coordinate value must be calculated for each l-dot to determine the pattern, so the processing time for graphic display is relatively short The problem is that it is long.

[Means for solving problems]

FIG. 1 is a block diagram showing the configuration of the present invention.

The figure shows a configuration in which pattern generation processing is performed in a processing device 3 based on specified information from a human-powered device 2 such as a keyboard, in order to display line segments on a display device 1. It has a continuous dot number determining section 4, a correction interval determining section 5, and a pattern setting section 6.

[For production]

When the input device 2 inputs a display designation specifying both parts of the line segment and the dot position, the consecutive dot number determination unit 4 of the processing device 3 starts processing, and calculates the vertical and horizontal distances between the two points. The larger of both distance values is set as the first number of dots, and the other is set as the second number of dots, and the quotient and remainder obtained by dividing the first number of dots by the second number of dots are calculated, and the quotient is stored as the number of consecutive dots.

Next, the correction interval determination unit 5 calculates a quotient by dividing the second tono)B by the previously obtained remainder, and records this as the correction interval.
do.

The pattern setting unit 6 creates a pattern in which the number of consecutive dots is lined up in the horizontal direction if the first number of dots is the distance in the horizontal direction, and in the vertical direction if not, in the direction from one end of the line segment to the other end. Line segments are displayed by shifting each column and sequentially arranging them without overlapping.

However, each time the number of patterns indicated by the correction interval is arranged, the number of consecutive display dots is increased by one dot, for example, only for the last pattern.

As described above, it is no longer necessary to calculate the position for each displayed dot, and the line segment display processing is speeded up.

〔Example〕

FIG. 2 is a flow chart showing details of the continuous dot number determining section 4, correction interval determining section 5, and pattern setting section 6 in the configuration shown in FIG.

When the process starts, in step 10, the dot coordinates (XIIyI) and (xz
, yz) horizontal distance dX and vertical distance d
Calculate y. Here, dX and dv represent the absolute value of the distance in terms of the number of dots, and are values that include the positions of the dots at both ends.

Further, it is assumed that the above coordinates at both ends are specified so that x1≦×2.

In step 11, for convenience of later processing, the larger of dX and d7, or if they are equal, for example d, is set to the variable d, and the other is set to d2.

In step 12, d is obtained by so-called integer division.

Divide by d2 to obtain the quotient n1 and the remainder r.

In step 13, n is stored in a predetermined register as the number of consecutive dots, and the remainder r is passed to the processing of the correction interval determining section 5, and the processing of the number of consecutive dots determining section 4 ends.

In the continuous dot number determination unit 5, the remainder r is 0 in step 14.
If it is not 0, an integer division is performed in which d2 is divided by r in step 15, and in step 16, the quotient n2 is stored in a predetermined register as a correction interval.

If r is 0, then in step 17 a fixed value, for example larger than the number of dots on any one side of the display screen, is set in the correction interval register. Thereafter, the next process of the pattern setting section 6 begins.

The pattern setting section 6 sets the coordinates (x, y
) are sequentially determined and displayed on the display device 1.

Initially, in step 18, (x, y) is changed to (x+, y+
) and reset the counter for correction interval control to 0.

In Step 19, starting from the initial values of (X, y), update X or y by 1 according to any of the following steps 1 to 2, and place only M n 1 dot at those dot positions. Displays a pattern of dots that connect horizontally or vertically. That is, if dx≧dy, add 1 to X.

■If dX<d, and y+<yz, add 1 to y.

■If dX<d, and y+>yz, set y to -I.

In step 20, the counter is incremented by 1, and in step 21, it is determined whether the counter value has become equal to 02. If not, the process proceeds to step 24.

If the value of the counter is equal to n2, in step 22 the coordinates are updated to add one more continuous dot and this dot is displayed, the counter is reset to O in step 23, and then the coordinates are updated in step 24. Proceed to.

In step 24, the coordinate X is +1 and y is 1/+〈yz
If V+ > Vz, then -1, and then in step 25, the new coordinate values (X, V) and (xz, yz) are compared to determine the end of processing, and the unprocessed section is If there is, the process returns to step 19; if not, the process is completed.

Through the above processing, for example, as shown in FIG. 3, the coordinates (X++y+) of the starting point 20 of the line segment are (4, 3) and the ending point 2
If the coordinates (xz, yz) of 1 are (23, 8), then d9
・Since we obtain 20 and d7·6, we get nl·3 and r·2, and from this we obtain 02·3.

Therefore, in this case, as shown in the figure, the line segment is displayed as a pattern of 3 consecutive dots in the horizontal direction and a 4-dot pattern of 4 dots once every 3 times.

〔Effect of the invention〕

As is clear from the above description, the present invention has a remarkable industrial effect in that display devices such as information processing systems can process line segment dot displays at high speed.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the configuration of an embodiment of the present invention, FIG. 2 is a flowchart of the processing of the present invention, and FIG. 3 is an explanatory diagram of an example of line segment display. In FIG. Figure 1 Explanatory diagram of -H column of line segment display

Claims (1)

[Claims] When generating a dot pattern that approximates a line segment connecting two dots on a screen displaying dots arranged orthogonally in the vertical and horizontal directions, Means for calculating a first quotient and a remainder by dividing a first number of dots that is not smaller than the other number of dots among the number of dots indicating the distance in the direction and including the dot position, by the other second number of dots. (4), and means (5) for calculating a second quotient by dividing the second number of dots by the remainder when the remainder is not 0, the distance indicated by the first number of dots; The above approximation is achieved by a pattern consisting of dots arranged consecutively in the direction of , the number of dots equal to the first quotient, and a pattern with one dot more than the pattern provided for every number equal to the second quotient. A pattern generation method characterized by (6) configuring a pattern.