JPS593693A - Figure drawing control system of printer - Google Patents

Abstract

PURPOSE:To print even a complicate figure at a high speed with a small-capacity figure memory by providing a region checking means which selects and processes only figure data whose regions are in a small writing region. CONSTITUTION:When figure data on one figure is read out of the figure buffer 1, the 1st region checking circuit 2 discriminates whether the figure is a linear figure or a circular figure from figure kind information. When it is the circular figure, maximum and minimum Y coordinates are found from center coordinate data and radius data; and only circular figure whose minimum Y coordinate value is less than the minimum Y coordinate value of the small region DP of writing or circular figure whose maximum Y coordinate value is greater than the minimum coordinate value of the small region DP is selected. When the figure is the linear figure, only a vector line (vectors a and c) which is present in the small region DP at least partially is selected.

Description

[Detailed Description of the Invention] (1) Technical Field of the Invention The present invention relates to a graphic printer that prints graphic data on a large screen, and in particular to a graphic printer that compresses the graphic memory and shortens the overall graphic drawing time. Concerning drawing control method.

(2) Prior art and problems As a method of recording figures, for example, a method of recording figures using an X-Y recorder is well known. Because the device is complex and difficult to control, graphic printers that can draw graphics in the same manner as regular character printers have been attracting attention.

Similar to character printers, graphic printers draw figures while horizontally scanning the recording section on recording paper that moves vertically.
A method in which the entire screen of one page is stored in one graphic memory, which is sequentially read out and printed. ■The entire screen is divided into multiple small areas and two graphic memories for each small area are prepared. There is a method of printing the entire screen of one page by repeating the operation of writing the next small area of graphics into the other graphics memory while reading and printing one graphics memory.

With the [Yes] method, the entire screen for one page is written to the graphics memory and then read out and printed, so even if the graphics become complex, there is no worry that the graphics processing speed will not be able to catch up with the printing speed. Enables high-speed printing. death,
However, since the graphic memory capacity is large, it has the disadvantage of being large and expensive.

Method (2) has the advantage that the capacity of the figure memory is small, but as the figure becomes more complex, the calculation time becomes longer, and even when printing in one figure memory is finished, writing to the other figure memory is finished. Things that aren't happening happen. For this reason, printing has to start after waiting for the writing in the other figure memory to finish, which has the disadvantage of slowing down the printing speed.This disadvantage becomes more pronounced as the area of the figure memory becomes smaller. . Therefore,
This will become a big problem when printing speeds are increasing as they are these days.The operation of processing graphics and writing it to the graphics memory is generally faster than the printing operation, and also when there are no graphics or only a small number of graphics. The write time is generally shorter than the print time. Therefore, even when a complex figure is created, the writing time to the figure memory is shorter than the printing time on average.

Therefore, even with the above-mentioned method, if the capacity of each graphic memory is increased, the dead time can be made smaller than the printing time. However, increasing the capacity of the graphic memory would go against the original purpose of the method (2), which is to perform printing f and r with a small capacity graphic memory, and its features would be lost.

(3) Object of the Invention The object of the present invention is to improve the problems of the above-mentioned method, and to provide a graphic drawing in a printer that can print even complex shapes at high speed by using all of the small-capacity graphic memory. This provides a control method.

(4) Structure of the Invention In order to achieve all of these objects, the graphic drawing control method in the printer of the present invention divides the entire screen into a plurality of small areas, writes the graphic data of these small areas into the graphic memory, reads it out, and then draws the graphic. ? The present invention is characterized in that a printer for printing is provided with a range check means for selecting and processing only the graphic data whose range is within a small area to be reloaded.

(5) Embodiment of the Invention An embodiment of the invention will be described in detail with reference to FIGS. 1 to 3.

FIG. 1 is a configuration diagram of an embodiment of the present invention, and FIGS. 2 and 3 are diagrams explaining its operation.

In the figure, 1 is a graphic buffer, 2 is a first range check circuit,
Reference numeral 3 designates a graphic calculation unit, 4 a second range check circuit, 5 a graphic drawing circuit, 6 a graphic memory, 7 a print control unit, and 8 a printer.

The operation of each part shown in FIG. 1 will be explained in sequence below.

■Graphic Buffer 1 Graphical buffer 1 stores graphical data for the entire screen corresponding to one page. This figure is classified into line figures such as polygon figures and curve figures, but curve figures can be divided into circular figures and curve figures other than circular figures. It is well known that approximate representations can be made, and that each line figure is given by coordinate data and vector information, and that circular figures are given by center coordinate data and radius data (in addition, in the case of circular arcs, the starting point and angle).

For example, in Figure 2, the quadrilateral ABCD is A, B, C
, D, vector a from point A to point B, vector b from point B to point 6, and vector from point C to D.
It is represented by vector information instructing to draw a vector c toward a point, and a vector di toward a point D from a point A. The triangle EFG is expressed by the coordinate data of each point E, F, and G, and the coordinate data of e, f, and g. Consists of vector information. Also yen CI
, C2 are given by coordinate data of center points C1 and C2 and radius data r, , r2.

The figure data stored in figure buffer 1 includes figure type information indicating whether the figure is a circle figure or a line figure, fill information indicating whether the figure has a filled part, and center coordinate data in the case of a circle figure. In the case of radius data and line figures, it consists of coordinate data of each point, vector information from each point, etc.

■ First range check circuit First, as shown in Figure 2, we will explain the operation of dividing the entire screen of one page into n small areas and storing and reading them using two graphic memos ' and lTh. Figure 2 shows all the figures drawn on the entire screen P for one page (as line figures, the quadrilateral ABC
D and triangle EFG, and circles C1 and C2 are shown as circular figures].

Now planning rMP=i Divide into n equal parts in the Y direction and form n
DI, D2,...
Let Dp, . . . Dn. The graphic memory writes and reads graphic data for one of these small areas (D+ -Dn), but since each small area and the graphic memory that writes and reads it correspond to each other, as shown in FIG. At the same time, we will represent a graphic memory, that is, a graphic memory tMp that writes and reads from the small area DI (i-Ms), a graphic memory tMp that writes and reads from the small area DI.

However, actual writing and reading of the small area is performed in two graphic memories (1112', 1112', not shown). That is, when the graphic data of the small area DI is being read from the graphic memory n]t storing the small area, DI f, the graphic data of the next small area D2 is simultaneously written into the graphic memory m2. When the reading from the graphic memory lJm1 is completed, the graphic data of the small area D2 is read from the next graphic memory m2, and at the same time, the graphic data of the next small area D3 is written to the graphic memory m1. Writing and reading of all the small areas up to the small area Dn will be repeatedly performed in the two graphic memories m12m2. However, for convenience of explanation, only the writing and reading of the small area of interest (for example, Dp) will be performed. The figure memory in the area has the same suffix (p) as the small area (Dp).
)e (that is, figure memory Mp).

By the way, when storing the entire screen P in one figure memory (method 2 explained at the beginning of the specification), it is necessary to calculate the coordinate data of all the figures and write the data.
When dividing into small areas as shown in Figure 2 and writing them to the corresponding figure memory, all ``coordinate data of figures?'' It is not necessary to calculate.

That is, the graphic data of the small area Dp is now stored in the graphic memory M.
When writing to p, the figures existing in the small area Dp, that is, figures other than the quadrilateral ABCD and the circle CI, the circle C2 and the triangle E
Calculating coordinate data for FG is not necessary at all since these coordinate data are not written in the equivalent figure memo IJDp. Furthermore, if we look at the quadrilateral ABCD, the calculation of the coordinate data on the vector line d that does not exist in the small area Dp is also possible because those coordinate data are stored in the figure memory D.
This is also unnecessary since it is not written into p.

In this way, it is not possible to calculate the coordinate data of circular figures and line figures that do not exist in the small area to be written, and of vector line parts that do not exist in this small area even if the line figures exist in the area that includes this small area. Not necessary.

Further, in the case of a circular figure, if a part of the figure exists within the 74% area where writing is performed, all coordinate data regarding the circumference is calculated. If you try to calculate coordinate data only in a small area, the software for that purpose will become more complicated and the calculation will take more time.

In this way, if all calculations of unnecessary figures and coordinate data of vector line segments are omitted, the figure data of the small area Dp can be written using the coordinate data on the vector lines a and C and the circle of the circle C1 for the quadrilateral ABCD. Since this is done by fully calculating only the coordinate data on the circumference, the time required to write it is greatly reduced compared to the conventional method, which also requires calculating the coordinate data of other figures and vector line segments. Therefore, the writing speed will be significantly improved.

The first range check circuit 2 checks the range of vector line segments of figures and line figures that do not require calculation of such coordinate data.

When graphic data regarding one graphic is read from the graphic buffer 1, the first range check circuit 2 first determines whether the graphic is a line graphic or a circular graphic based on graphic type information. (Processing of fill information will be explained later in section ■.) If the figure is a circle, the maximum and minimum values of the Y coordinate are calculated from the center coordinate data and radius data (the Y coordinate is shown in Figure 2 in this explanation). As the downward direction is the positive direction, the lower the Y coordinate value becomes a dog), and the minimum Y coordinate value is smaller than the maximum Y coordinate value of the small area Dp as the small area k Dp to be written. Or the maximum Y coordinate value of the circular shape is small area D
A circular figure larger than the minimum Y coordinate value of p (in Figure 2, circle C
Select only 1) and exclude all other circle shapes (circle C2). If the figure 2 shape is a line shape, the coordinate data and vector information of each point are read out sequentially, so from these data Select only the vector lines (vectors a and C) for which at least a portion of the vector line segment exists in the small region Dp, and exclude all other vector line segments.This results in triangle E.
FG is all eliminated, and even in quadrilateral ABCD, when the vector line is segmented, d is eliminated.

Circle figure C1 and quadrilateral ABC selected in this way
Only vector line segment a of D and graphic data of C are sent to the graphic calculation unit 3.

(2) Graphic calculation unit 3 The graphic calculation unit 3 calculates the XY coordinates on the circumference of the circular figure C1 and on the vector line segment c. X, Y coordinates are microcephalic area D
p, that is, figure memo 1. It is calculated in the same step as the resolution of the entire surface element composing l'.

For vector line segments of a line figure, for example, all coordinate data of the vector line segment at the left end is calculated in order. That is, the second
In the case of the figure, the coordinate data of vector line C is calculated next to vector line a.

In the case of a circular figure, for example, first calculate the coordinate data of the left half, then the right half, and in both the case of a line figure and a circular figure, the coordinate data is calculated using all Y coordinate parameters and the corresponding X By calculating the coordinates in this way, subsequent processing can be performed quickly and easily, as described below.

In this way, the graphic calculation unit 3 first outputs the coordinate data of the vector line a using the Y coordinate as a parameter, then similarly outputs the coordinate data of the vector line a, and then outputs the coordinate data of the left hand of the circle C1. is similarly output, and finally the coordinate data of the right half of the circle C1 is also output using the Y coordinate as a parameter and is supplied to the second range check circuit 4.

(2) Second Range Check Circuit 4 The second range check circuit 4 checks the coordinate data of figures within the small region Dp and processes the painting information. Since the process is the same for line figures and circle figures, these processes will be explained using FIG. 3, taking a circle figure as an example.

■-1 Check circle C for coordinate data of figures in small area
] Coordinate point on the circumference (R, + -R, t3. R, +'
~RI3'), the coordinate point (
)14~几101R4'~R1o') are stored in the figure memory Mp, so the other coordinate points (l
(, +~R3゜R+'~1113', R11-Rl3
+R11' to RI3') coordinate data is unnecessary. Therefore, by eliminating the processing of these unnecessary coordinate data, the coordinate data can be easily and quickly stored in the graphic memory Mp.

As mentioned above, the second range check circuit 4 has coordinate points (from 几1 to
The 4-vote data for l (, +s, 11 to 131) is Y
Supplied with coordinates as parameters. This second range check circuit 4Fi compares the Y coordinate of each coordinate point with the minimum Y coordinate Ymin and maximum Y coordinate Ymax of the small area Dp, and determines the coordinate that satisfies the condition Ymin<Y coordinate of the coordinate point<Ymax. Only the points (R4-R10, 几4゛~RIO) are selected and supplied to the next graphic drawing circuit 5.

The graphic drawing circuit 5 converts the X and Y coordinates of each coordinate point into the corresponding X and Y addresses of the graphic memory Mp and writes the data.

■-Double-sided painting Information processing side-painting means filling in the entire interior of a figure.
The process is the same for both circular and line shapes, so in the case of a circle, the gold side will be explained with reference to FIG.

When performing surface painting υ with a printer, the surface painting is performed by performing main scanning in the X direction and then sub-scanning 1 to 1 in the Y direction, so circle C1
When painting on two sides, between R1 and R1', and between R2 and R2'
Area painting is performed by printing each X coordinate point between R13 and Fjts' in black.

Therefore, when performing area painting, a point on the circumference of circle C1 (
In addition to R+~RI3, R+'-I-t+a'), it is also necessary to store data at each coordinate point (between R+~R1')~(RI3~l(, +3') in the figure memory. 7 However, in this case too, between (R+-R+“) and (R13
~R13') and (Ro~R111)~(R13~
The coordinate data between R131) is not stored in the graphic memory Mp of the small area Dp, and therefore becomes unnecessary.

The second range check circuit 4 first checks the small area D of the figure for which the fill information has been detected using the same method as in (1) above.
Coordinate points within p (R4-R10°R4°~R+o')
Select all, then each coordinate point (R4 to RIO) of the line segment on the left side of the shape
is given a filling start point sign, and each coordinate point of the right line segment (
R4' to R1o') are given a fill end point code and supplied to the next graphic drawing circuit 5.

In this way, only the fill information of the figure part in the small area Dp is sent to the next figure drawing circuit 5. 2.Figure drawing circuit 5 and figure memory 6 The figure memory 6 stores the coordinates of all pixels in the small area Dp. Consists of two memories with a capacity to store data,
Write on one? While this is being done, data is read from the other one and sent to the print control unit 7, but this operation is similar to that of a conventional character printer. teeth,
The X and Y coordinates of each coordinate point of the figure are converted into the corresponding X and Y coordinate addresses of the entire figure memory Mp and written. As a result, the same graphic pattern as the graphic in the small area Dp of FIG. 2 is stored in the graphic memory Mp.

In the case of a figure with fill-in, the memory bit between the start point of fill-in and the end point of fill-in is also written.This allows the figure to have fill-in like the figure in the small area Dp in Figure 3. The graphic pattern is stored in the graphic memory Mp. Print Control Unit 7 and Printer 8 The grid control unit 7 controls the printer 8 using the graphic data read from the graphic memory, using the same method as a conventional character printer. The figure is printed while scanning the recording paper.

Although the above description has been made regarding a single figure, the present invention is not limited to this, and may be applied to a figure in which a plurality of vector information is assigned to one coordinate point, such as a coordinate point in quadrilateral ABCD in FIG. It can also be applied to drawing a figure in which there is a vector line AC from A to another coordinate point C in addition to vector b.

It can also be applied to cases where characters and graphics are included by writing character data into the graphics memory 6 in the same way as in conventional character printers.

(6) Effects of the Invention According to the present invention, graphic data in areas other than the divided small areas is not processed, so the processing time for graphic data is significantly reduced, and even complex figures can be drawn at high speed. becomes. In addition, it is possible to realize a small holder for the figure memory without reducing the printing speed.

[Brief explanation of drawings]

Example FIG. 1 is a schematic diagram of one implementation of the present invention, and FIG. 2 is an explanatory diagram of the operation of the present invention with the operation sound of the first range check circuit suppressed.
FIG. 3 is an explanatory diagram of the edge painting process, focusing on the operation of the second range check circuit. In the figure, ■ is a graphic buffer, 2 is a first range check circuit,
3 is a graphic drawing trowel 1 part, 4 is a second range check circuit, 5 is a graphic drawing circuit, 6 is a graphic memory, 7 is a print control unit, 8
is a printer. Patent applicant Fujitsu Ltd. Representative Patent Attorney Akira Yamatani

Claims (1)

[Claims] α) In a printer that divides the screen into multiple small areas, 2 writes and reads all the graphic data of these small areas to the graphic memory, and then prints the figures, only the range of graphic data is within the small area to be written. A graphic drawing control method for a printer, characterized in that a range checking means for selecting and performing processing is fully utilized.