JPH0444309B2 - - Google Patents

Description

[Detailed Description of the Invention] [Summary] This is a control method for drawing a line figure, and when drawing a line figure with a moving locus of rectangular pixels consisting of multiple pixels, the moving direction of the pixels is vertical or horizontal. The rectangular drawing processing unit performs drawing in the case of , and the hook-shaped drawing processing unit performs drawing in the diagonal direction. This eliminates the need to draw multiple pixels and enables high-speed drawing.

[Industrial application field]

The present invention relates to a method for drawing line figures in an image display device using pixel trajectories.

Image display devices display images using pixel points that make up the image, but to form a line figure,
The method of drawing by specifying the addresses of pixel points one by one takes processing time, so there is a method of moving the pixels that make up one small figure in a group of pixel points and forming a line figure image using the locus as the display pixel. It is being done.

Figure 4 shows the method, where rectangular pixel A is
Draw with the trajectory moved to A′.

However, there is a need for a more efficient and faster drawing method.

[Conventional technology]

As shown in the configuration block diagram of the conventional example in FIG. 5, when a drawing command is input from the host computer to the drawing instruction section 1, the drawing instruction section 1 separates the pixel command and sends it to the pixel management section 2, and the pixel management section The portion 2 constitutes a pixel (for example, a rectangle in FIG. 6).

The drawing instruction section 1 separates the movement command, and the movement processing section 3 writes the pixel specified by the pixel management section 2 to the new movement position to which the pixel in the frame memory 4 has been moved, and displays it on the display section 5.

As shown in Figure 6, when drawing a diagonal figure whose pixels are in the area within the chain line, for example, if the pixels are a rectangle with 4 x 5 pixels, and the pixels of this rectangle move in the moving direction shown, the pixels will change. Every time the distance of one pixel is moved, all the pixel points of the rectangular pixels at the new position are drawn as a new image.

[Problem that the invention seeks to solve]

In this conventional method, each pixel is filled in and shifted each time the pixel moves by one pixel distance.

That is, new pixels are always drawn, but since most of the pixels before and after the movement overlap, the overlapping parts of the pixels are processed twice, resulting in wasted time.

The present invention was created in view of these points, and an object of the present invention is to provide a method that reduces drawing time by omitting drawing of overlapping portions.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides an image display device that draws on the trajectory of rectangular pixels. When a pixel is set to move in one direction vertically or horizontally, the inside of the rectangle whose width is the length of the vertical movement or the width of the pixel is the length of the horizontal movement is filled with a closed area filling method to create a vertical or horizontal line. Draw shapes.

When a pixel is set to move in the direction of the diagonal image rotation position, one side of the pixel facing the direction of movement and the other side perpendicular to the side are drawn as new pixel points.

[Effect]

A rectangular drawing processing unit that draws a vertical line or horizontal line fills in the rectangular area formed by the starting point and ending point of the drawing by moving pixels vertically or horizontally all at once using an already developed outline filling means.

When a pixel moves in a diagonal direction, a hook-shaped drawing processing section draws a hook-shaped pixel figure constituted by the sides of the pixel facing the pixel movement direction every time the pixel moves by one pixel position.

The rectangular drawing processing section and the hook-shaped drawing processing section are selectively used depending on the moving direction of the pixels, and it is possible to quickly draw a line figure including a curved portion without repeating drawing.

〔Example〕

The line figure drawing control system of the present invention will be explained in detail below with reference to the drawings.

FIG. 1 is a block diagram of the configuration of an embodiment of the present invention, FIG. 2 is an explanatory diagram of pixel movement, and FIG. 3 is an explanatory diagram of drawing point movement. Note that the same reference numerals indicate the same objects throughout the figures.

In FIG. 1, a drawing instruction unit 1 separates a drawing command sent by a host computer into a pixel command and a movement command, and transfers the pixel command to a pixel management unit 2.
Send to.

Based on this pixel command, the pixel management unit 2 sets pixels, but as shown in Figure 2, which is the same as above, 4 and 5 pixel points are set in the horizontal (X-axis) direction and vertical (Y-axis) direction. Draw a rectangle consisting of.

In order to simplify movement expression, this pixel movement is expressed by using, for example, the lower left end pixel of this rectangular pixel as a drawing point P.

On the other hand, the movement command is input to the movement direction setting section 6, and the movement direction of the pixel is set.

That is, as shown in FIG. 3, the point to which the drawing point P(Δ) moves next becomes the pixel position indicated by the X and Y coordinates which is one pixel distance away from the point before movement as the origin.

When the movement direction setting section 6 sets the drawing point to move in the X-axis direction, for example, and the starting point is P and the end point of the movement in the same direction is P', the rectangle drawing processing section 7 sets the pixel data of the pixel management section 2, That is, the rectangular area that is the pixel locus of LL'M'M, including the pixel area, is filled in, and the horizontal line figure data with a height of 5 pixels and length LL' is stored in the frame memory 4, and displayed on the display section. Displayed as 5.

When the drawing point moves in the Y-axis direction, a vertical line figure with a width of 4 pixels and a length MN as shown in the figure is drawn.

When the moving direction setting section 6 sets the moving direction of the drawing point to move in an oblique direction, the hook-shaped drawing processing section 8 draws a new drawing point every time one point moves.

For example, if the drawing P(△) moves to (1, 1), set a hook-shaped (inverted L-shaped) figure consisting of the right side and the upper side of the pixel as shown in Figure 2b, and Pixel points marked with a dotted line ◯ made up of the pixel points on the sides are generated and written into the frame memory 4.

In this way, when a pixel moves in the diagonal direction, a hook-shaped figure is generated for each moving pixel position, and the diagonal line figure shown within the chain line in FIG. 2b is drawn.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to perform high-speed drawing by avoiding duplication of pixel drawing, which is extremely useful in practice.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the configuration of an embodiment of the drawing processing method using pixel outlines of the present invention, Fig. 2 is an explanatory diagram of movement of pixels, Fig. 3 is an illustration of movement of drawing points, and Fig. 4 is drawing by pixels. FIG. 5 is a configuration block diagram of a conventional example, and FIG. 6 is an explanatory diagram of a conventional drawing. In the figure, 6 is a movement direction setting section, 7 is a rectangle drawing processing section, and 8 is a hook-shaped drawing processing section.

Claims (1)

[Scope of Claims] 1. In an image display device that draws a line figure on a screen in which pixel positions to be displayed are arranged at equal intervals vertically and horizontally, using a movement locus of rectangular pixels composed of a plurality of vertical and horizontal pixels, the pixels A pixel movement direction setting unit 6 that sets the direction in which the position moves, and when the pixel movement direction setting unit 6 sets the pixel to move in one direction vertically or horizontally, the length of the vertical movement is determined by the horizontal width of the pixel. , or a rectangular drawing processing unit 7 that draws a rectangular outline having a vertical width and a horizontal movement length of the pixel as a pixel using a closed area filling means; When movement in the positional direction is set, a key-shaped drawing process is performed in which one side of the pixel that is currently facing in the moving direction and the other side orthogonal to that side are drawn as a new pixel each time the position moves by one pixel. A line figure drawing control system characterized by comprising: a section 8.