JPH02153483A - Horizontal side picture drawing system in graphic surface painting processing - Google Patents

Abstract

PURPOSE:To exactly execute the picture drawing of a graphic by inserting a horizontal side or deleting a specific X coordinate from an output table with respect to the output table before picture drawing is executed to a bit map memory. CONSTITUTION:The number of X coordinates in an output table being smaller than an X coordinate of a small or large horizontal side is counted, and when it is decided that its number is an even number, the X coordinate of a small horizontal side is inserted into the output table 3, but when it is decided that the counting value is an odd number, the X coordinate of the output table 3 remains unchanged. Also, X coordinate values in the output table being over the X coordinate of the small horizontal side, and also, under the X coordinate of the large horizontal side are all deleted. In such a manner, in accordance with the output table 3, picture drawing can be executed to a bit map memory 6, and accordingly, it does not occur that the horizontal side is missing due to the shape of a graphic and surface painting can be executed exactly.

Description

[Detailed Description of the Invention] [Table of Contents] Overview Industrial Application Fields Prior Art and Problems to be Solved by the Invention Means for Solving the Problems Action Examples Effects of the Invention [Summary] Multiple forms that take any form A figure is made up of vertices that make up a rectangle,
When performing surface painting by filling in the inside of that side,
A table in which sides other than horizontal sides are sorted in order of X coordinate values,
A table (AET) that generates parameters for finding each point necessary to fill the inside of the side based on the table.
Find the X coordinate of ° versus ゛ to fill in, and calculate the
The purpose of this project is to solve the problem that, depending on the shape, accurate surface painting is not performed depending on the horizontal edge drawing method when painting the surface of a shape by outputting each pixel between the X coordinates of the pair. A horizontal side table consisting of the X coordinate of the starting point and the X coordinate of the ending point of the horizontal side forming the polygon.

an output table that stores the X-coordinates of the pairs for filling the polygon, and a starting point of one horizontal side read out by searching a horizontal side table that intersects with the X-coordinates for each X-coordinate value forming the polygon; providing logical means for comparing the X coordinate of the end point with the X coordinates of the "pair" of starting and ending points in the output table;
The logic means counts the number of X coordinates in the output table that are smaller than the X coordinates of the starting point or end point of the horizontal side, determines whether the number is an "even number" or "odd number," and reads the one For each horizontal side, if the determination result is an "even number" for the
As a coordinate, insert it into the X coordinate of 'v' in the output table, and if the judgment result is an "odd number", set it as the side of the X coordinate of 'v' in the output table, and the starting point of the horizontal side, Delete the X coordinate in the output table that exists between the X coordinates of the end point for all horizontal sides in the horizontal side table, and insert the X coordinate in the horizontal side table in the output table, or , specific X from the above output table
Configure to delete coordinates.

[Industrial application field]

In the present invention, when a figure is composed of vertices constituting a polygon having an arbitrary shape, and the area is painted by filling in the inside of the sides, the sides other than the horizontal sides are arranged in the order of the X coordinate value. Based on the sorted table and the table (AET) that generates parameters for finding each point necessary to fill in the inside of the side, the "pair" of X coordinates for filling in the side is determined. The present invention relates to a horizontal side drawing method when filling the surface of a figure by determining the value of , and outputting each pixel between the X coordinates of the pair.

Recently, the field of creating documents using computer systems such as word processors has been attracting attention.

This document is becoming more and more multimedia, including not only documents but also graphs and figures, but currently,
In many cases, only simple shapes such as circles and rectangles are handled, and there is no function to draw complex shapes such as polygons with arbitrary shapes. In the field of document creation using word processors and the like, there has been a demand for the ability to draw complex drawings as described above.

[Prior art and problems to be solved by the invention] Fig. 3 is a diagram explaining a horizontal edge drawing method in conventional figure surface painting, in which (a) shows an example of the configuration of a drawing mechanism, and (b) - (
f) shows the operation flow of the conventional method, and FIG. 4 is a diagram explaining the problems of the conventional method, in which (a) shows the normal case, and (b) shows the case where the horizontal side cannot be drawn. , (c) shows an example of how to deal with it.

Conventionally, in processing polygons that take arbitrary shapes, a method is used in which a figure is constructed from the vertices that make up the polygon, and the area is filled by filling in the inside of each of the constructed sides.
For example, (“Raster graphics software (
6), "Scan conversion of r polygons (2)" by Yoshio Ohno, magazine "prXEL" 1, published by Graphic Processing Information Center, llh 16. Pages 136-141.1984
)It has been known.

Hereinafter, the outline of the surface coating method shown in the above-mentioned document will be explained below with reference to FIG.

■ First, in the data input unit 10 shown in FIG. 3(a), a table of vertices forming a polygon ((a) in FIG. 4(a)
), see (b)) is generated, and each side of the polygon is examined one by one in the arithmetic processing unit (5a).

At this time, horizontal sides are ignored, and for non-horizontal sides,
Focusing on the end point with the smaller Y coordinate, the sides are rearranged so that the end points are arranged in ascending order.

As a method for this sorting, for example, so-called packet sorting is used. (See step 100 in Figure (b). (c)) The sort table 1 generated in this way is shown in Figure 4 (
B) This is shown in (C).

■ First, the Y coordinate value yc to be processed is set to 0, and the above ■
The following processing is performed on the sides rearranged in ascending order of Y coordinate in ascending order of X coordinate value.

That is, if there is a side whose starting point is the X coordinate value (yc) to be examined, that side (sides p, p, , p, p4...- of the polygon shown in Figure 4 (a)) ) is registered in the parameter generation table (AET) 2 described above, and the parameters (X coordinate value for each X coordinate value, change amount (ΔX, ΔY
), -) and calculate the height of each side (the calculation method will be described later).

Therefore, the edge registered in the parameter generation table (AET) 2 has an intersection with an unprocessed X coordinate value (an X coordinate value larger than the one currently being processed) (yc). (See step 101 in the figure (b). (d)) ① In the process ① above, the side whose height has become °O゛ is deleted from the parameter generation table (AET) 2.

In other words, if the edge intersects with the X coordinate value (yc) that has been processed in (■) above, but does not intersect with the X coordinate value (yc) that has not yet been processed (in other words, if the corresponding selection ), the height of the side becomes O", the side is deleted from the parameter generation table AET)2, but the height becomes O".
If it is not 0゛, move on to the next process (■).

As a result, the only edges remaining in the parameter generation table (AET) 2 are those that intersect with the X coordinate value (yc) to be processed from now on. (See step 102 in the figure (b). Step 102a in (e)) ■ For the sides that were not deleted in the process of ■ above, the X coordinate values of the intersections with the X coordinate value (yc) currently being processed are arranged in order. , the odd-numbered and even-numbered pairs are created, and registered in the output table 3, for example, and the height of the registered side is decremented.

The area between this pair of X coordinates is the area to be covered.

■ Add 1 to the X coordinate value (yc) to generate the next Y coordinate to be processed, and return to ■. (Step 10 in the figure (b)
3.104. (See (f)) The above-mentioned processes ① to ② are executed for all the X coordinate values (yc). (See step 105 in (b)) For the polygon shown in FIGS. 4(a) and 4(a),
This will be explained more specifically.

The polygon consists of eight vertices, and as shown in figure (b), the coordinate values of each vertex are, in order, PI (5, 25),
Pz(5,5), Pi(15,5), P4(15,10
), P5(20,10), P6(25,15), Pt(
25,20) and Pi(20,25).

As a result of the above process (2), the sort table 1 shown in FIGS. 4(A) and 4(C) is obtained.

The processes from ■ to ■ are executed in order for the X coordinate values (yc) 0 to 30 based on the above sort table 1, and each time the pair of X coordinates described in ■ is obtained, the parameter generation table (AET) is Decrement the height of the side in 2, and when the height of the side becomes 0", as explained in , is applicable).

Here, the above-mentioned height calculation method will be explained.

Figure 4 (a) (a) The side p of the polygon shown in (b)
If the next side of sp6, p, and p is connected vertically, calculate the height = (Y coordinate of the end point) - (Y coordinate of the start point).

In addition, when there is a maximum point of the Y coordinate between p, p, and P7pH, the height is determined by height = (Y coordinate of the end point) - (Y coordinate of the starting point).

Also, like P3P, P, and P6, there is a horizontal side (P4P
S) exists, the horizontal side (P4.P%) is ignored and processed, and there is no maximum point of the Y coordinate, so in the case of the corresponding side P:lP4, the height - (Y coordinate of end point) - (Y coordinate of starting point) l.

In either case, if there is a horizontal edge between them, that horizontal edge is excluded from processing.

In this way, the registration table 3, which is the execution result shown in FIGS. (a) and (d), is obtained. At this time, the execution result may be directly drawn in the focus map memory 6.

In the conventional method outlined above, as pointed out in the above-mentioned literature, accurate surface painting may not be performed depending on the figure.

For example, if we process the polygon shown in Figure 4(B)(a), which is upside down from the polygon in Figure 4(a), as is clear from Figure 4(d), P4P, edges may not be drawn. That is, there is a problem that the horizontal sides are not accurately drawn.

As a way to solve this problem, for example, as shown in Figure (C), the horizontal edge is registered in a separate table, and when the above-mentioned surface painting process is completed, only this horizontal edge is registered. One possible method is to draw it.

However, with this method, the points drawn twice (indicated by diagonal lines)
occurs, so if you perform a logical operation with the edge to be written, such as exclusive OR, it is possible to draw the edges p, p, which could not be drawn, but the edges indicated by p2p and P, P are erased. There was a problem with being exposed.

In view of the above-mentioned drawbacks of the conventional art, the present invention constructs a figure using vertices constituting a polygon having an arbitrary shape, and fills in the interior of the sides to fill in the sides other than the horizontal sides. Y
Based on the table sorted in the order of coordinate values and the table (AET) that generates parameters for finding each point necessary to fill in the inside of the side, it is possible to In the horizontal side drawing method when filling the surface of a figure by determining the X coordinate of the pair as an output table and outputting each pixel between the X coordinates of the pair based on the output table, bit Horizontal edge drawing method in figure surface painting process that draws accurate figures by inserting horizontal edges into the output table before drawing in the map memory or deleting specific X coordinates from the output table. The purpose is to provide the following.

[Means to solve the problem]

FIG. 1 is a diagram showing the principle of the horizontal side drawing method in the figure surface painting process of the present invention.

The above problem can be solved by a horizontal side drawing method configured as follows.

A figure is composed of vertices that make up a polygon of any shape,
When performing surface painting by filling in the inside of that side,
Based on Table 1, in which sides other than the horizontal sides are sorted in order of Y-coordinate values, and Table 1, we create a table (^ E
T) 2, the x-coordinate of the "° vs."
In the method of painting the surface of a figure by outputting each pixel between the X coordinates of the pair, the X coordinates of the pair are stored as an output table 4, and the horizontal sides forming the polygon are A horizontal side table 3 consisting of the X coordinate of the starting point and the A logic means 5 is provided for comparing the X coordinates of the start point and end point of one horizontal side retrieved and read out with the X coordinates of the start point and end point of the ° pair in the output table 3. , count the number of X coordinates in the output table 3 that are smaller than the X coordinates of the starting point or end point of the horizontal side, determine whether the number is an "even number" or "odd number," and calculate from the horizontal side table 4. Regarding one read horizontal side, if the determination result is "even" with respect to the X coordinate of 'vs' read from the output table 3, the X coordinate of the horizontal side is set to the X coordinate of the output table 3. Coordinates in the above output table 3 “
If the judgment result is an "odd number", it is placed on the side of the X coordinate of the pair ' of the output table 3, and between the start point of the horizontal side and the X coordinate of the end point. Delete the existing X coordinate in the output table 3 for all horizontal edges in the horizontal edge table 4, and insert the X coordinate in the horizontal edge table 4 into the output table 3, or It is configured to delete a specific X coordinate from table (3).

[Effect]

That is, according to the present invention, when a figure is made up of vertices constituting a polygon having an arbitrary shape and the area is painted by filling in the inside of the side, the X coordinate of the side other than the horizontal side is (y
c) A table sorted in the order of values and a table (AET) that generates parameters for finding each point necessary to fill in the inside of the side based on the line table. Conventionally, in the horizontal side drawing method when filling the surface of a figure by determining the X coordinate of the pair " as an output table and outputting each pixel between the X coordinate of the pair " based on the output table, When generating a sort table using the method, register the horizontal edge in a separate table.

In addition, when calculating a pair of X coordinate values (Yc) and an X coordinate value of a side having an intersection using the conventional method, the X coordinate values of this pair are not drawn directly in the bitmap memory, but are written in the output table as described above. Remember it as.

The X coordinate value (y
c) The X coordinates of the starting point and ending point for each, and the X coordinates of the starting point and the ending point of the horizontal side table, and the corresponding
After each comparison is made using the following logic and the X coordinate of the horizontal side for which the condition is met is inserted into the output table, it is drawn in the bitmap memory.

(1) Count the number of X coordinates in the output table that are smaller than the X coordinate of the smaller or larger horizontal side, and if the number is determined to be an even number, the X coordinate of the smaller horizontal side. is inserted into the output table, but if the count value is determined to be an odd number, it is set to the side of the X coordinate of the output table.

(2) Delete all X coordinate values in the output table that are greater than or equal to the X coordinate of the smaller horizontal side and less than or equal to the X coordinate of the larger horizontal side.

Since it functions in this way, by storing the data in the bitmap memory according to the output table obtained by implementing the present invention, there is no possibility that the horizontal edges will be missing depending on the shape of the figure, and accurate filling can be achieved.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

The above-mentioned FIG. 1 is a diagram showing the principle of the horizontal edge drawing method in the figure surface painting process of the present invention, and FIG. 2 is a diagram schematically showing the horizontal edge insertion logic of the present invention. The horizontal side table 4 shown and the output table 3. and comparison logic circuit 5
Accordingly, means for determining insertion of the X coordinate of the horizontal side and deletion of the X coordinate in the output table 3 as shown in FIG. 2 is necessary for carrying out the present invention. Note that the same reference numerals refer to the same objects throughout the plan.

Hereinafter, the horizontal side drawing method in the figure surface painting process of the present invention will be explained with reference to FIG. 2 while referring to FIG.

Even if the present invention is implemented, sort table 1. The operations up to generating the parameter generation table (AET) 2 and generating the X coordinate pair information indicating the section to be filled out to be drawn in the bitmap memory 6 based on the parameter generation table (AET) 2 are conventional. Since there is no particular difference from the method, the explanation will be omitted, and the operation of the comparison logic circuit 5 of the present invention will be mainly explained here.

In the present invention, when the data input unit 10 shown in the principle diagram of FIG. 1 generates a table of vertices constituting a polygon, and then the arithmetic processing unit 5a generates the sort table 1, the conventional Create the horizontal side table 4 that was previously used.

Then, based on the sort table 1, the arithmetic processing unit 5
After calculating the pair of X coordinate values of the sides of the polygon that have the intersection with the X coordinate value from the parameter generation table (AET) 2 generated in step a, in the case of the present invention, the pair is stored in the output table 3. and the X coordinate value (y
c), the next comparison logic circuit 5 compares the X coordinate values of the start point and end point of the pair information stored in the output table 3 with the X coordinates of the start point and end point of the horizontal side table 4, respectively. Logic part (CI), (C2) 5L52, Fig. 2 (
Compare the cases in 11 cases shown in 11 to αυ, count the number of X coordinates in the output table 3 that are smaller than the X coordinates of the starting point and ending point of the horizontal side, and see if there is an even number.

Whether there is an odd number or not is determined by the even/odd determining sections 53 and 54 as shown in FIG.

For example, in case (1), when comparing the X coordinate of the smaller horizontal side and the X coordinate of output table 3, the X coordinate of the smaller horizontal side is the Since the number of X coordinates in the output table 3 that is smaller than the
An even number.

Also, when comparing the X coordinate of the larger horizontal side and the X coordinate of the output table, there is a relationship: X coordinate of the larger horizontal side > X coordinate of the smaller output table, so the larger horizontal side Since the number of X coordinates in the output table smaller than the other X coordinate is "l", the determination result by the even/odd determining section 54 is "odd number".

Hereinafter, in the same manner, the determination results shown in FIG. 2 are obtained for each of cases (2) to αυ.

Based on this determination result, the X coordinate value of the horizontal side is inserted into the corresponding position in the output table using the following logic.

1) Count the number of X coordinates in the output table 3 that are smaller than the X coordinate of the smaller or larger horizontal side, and if the number is determined to be an even number, calculate the X coordinate of the smaller horizontal side. is inserted into the output table 3, but when the count value is determined to be an odd number, it is set to the side of the X coordinate of the output table 3. (Based on the even-odd judgment circuits 53 and 54 in FIG. 1)2
) The X coordinate value in the output table 3 that is greater than or equal to the X coordinate of the smaller horizontal side and less than or equal to the X coordinate of the larger horizontal side (for example, in the case of Fig. 2 (2), the deletion of Fig. 1 Judgment section 5
5)).

The final result of the output table 3 generated in this way is drawn in the bitmap memory 6.

When the horizontal side drawing process according to the present invention is applied to the polygons shown in FIG. 4(b) (a) and (d),
．． 25, it is classified as αυ case in Figure 2, and when Y coordinate value = 20, it is classified as 00) case in Figure 2, so as a result, the horizontal side can be drawn accurately. Become.

In this way, the present invention configures a figure with vertices constituting a polygon having an arbitrary shape, and when performing area painting by filling in the inside of the side, the X coordinate of the side other than the horizontal side is Based on the table sorted in the order of the values of , and the table (AET) that generates parameters for finding each point necessary to fill the inside of the side, the ° pairs for filling the inside of the side are generated. In the horizontal edge drawing method when filling a figure by finding the X coordinate of ゛ and outputting each pixel between the X coordinates of the ``pair'', the X coordinate of the ``pair'' is stored as an output table. In addition, by separately providing a horizontal side table and comparing the output table and the horizontal side table with respect to the horizontal side that intersects with the above X coordinate and the pair of X coordinates in the output table, the horizontal side table can be calculated. Count the number of X coordinates in the output table that are smaller than the X coordinates of the smaller and larger ones, and if the number is even, insert the X coordinate of the horizontal side into the output table, and if the number is odd, insert it into the output table Using the middle X coordinate, the smaller X coordinate of the horizontal side or higher,
The feature is that the output table to be drawn in the bitmap memory is generated by deleting all the X coordinate values in the output table below the larger X coordinate.

〔Effect of the invention〕

As explained above in detail, the horizontal edge drawing method in the figure surface painting process of the present invention constructs a figure with vertices that make up a polygon of an arbitrary shape, and then fills in the inside of the side to create a surface. When painting, create parameters to find each point necessary to fill the inside of the side based on a table in which sides other than horizontal sides are sorted in order of X coordinate value and a line table. Using the table (AET), calculate the X coordinate of the "pair" for filling, and output each pixel between the X coordinates of the "pair" to draw the horizontal side when filling the surface of the figure. In the method, a horizontal side table consisting of the X coordinate of the starting point and the X coordinate of the end point of the horizontal side forming the polygon, an output table storing the X coordinate of the pair for filling the polygon, and the above For each X coordinate value that constitutes a polygon, the X coordinates of the start point and end point of one horizontal side read out by searching the horizontal side table that intersects with the X coordinate, and the start point and end point of the pair in the output table. and a logical means for comparing the X coordinate with the X coordinate, and the logical means counts the number of X coordinates of the output table that are smaller than the X coordinate of the starting point or the ending point of the horizontal side, and determines that the number is an "even number". For the one horizontal side read above, the judgment result is "even number J" for the X coordinate of the pair read from the output table.
In this case, insert the X coordinate of the horizontal side as the X coordinate of the above output table into the X coordinate of ′ vs. For all horizontal sides in the horizontal side table, delete the X coordinate in the output table that exists between the X coordinate of the horizontal side and the starting point of the horizontal side and the X coordinate of the end point. , the X coordinate in the horizontal side table is inserted into the above output table, or a specific X coordinate is deleted from the above output table, so the contents of the output table by executing the present invention are stored in the bitmap memory. By drawing, the horizontal sides of the figure will not be missing depending on the shape of the figure, and the area will be painted accurately.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the principle of the horizontal side drawing method in the figure surface painting process of the present invention. FIG. 2 is a diagram schematically showing the horizontal edge insertion logic of the present invention. FIG. 3 is a diagram illustrating a horizontal side drawing method in conventional figure surface painting. FIG. 4 is a diagram explaining the problems of the conventional method. Go out. 4 is a horizontal table, and 5 is a comparison logic circuit. 5a is an arithmetic processing unit. 51 and 52 are comparison logic units (CI, C2). Reference numerals 53 and 54 denote an even-odd determining section, and 55 denotes a deletion determining section. 6 is bitmap memory. 100, 101a, and 101 to 105 are processing steps. (1) ~ 0υ is the horizontal side pattern between the horizontal side table and the output table. P1 to P8 are the vertices of the polygon. p, p, , -・ are the sides that make up the polygon. y and yc are X coordinates or X coordinate values. are shown respectively. In the drawing, 1 is a table other than the horizontal side or a sort table. 10 is a table of vertices that make up a polygon. 2 is a parameter generation table (AET). 3 is an output table or a registration table. Cause → Toku (α) Figure of the Saien (A row of lines) ) Opening spoon 0 payment of the 2 directions of the cane) Figure (No. 1) (α) Tsu) Ohi Tsumeo 2〇 station evacuation, please explain the illustration year 4 listening α No. 3 )

Claims (1)

[Claims] A figure is constituted by vertices constituting a polygon having an arbitrary shape,
When performing surface painting by filling in the inside of that side,
Table in which sides other than horizontal sides are sorted in order of Y coordinate value (1
), and a table (AET) that generates parameters for finding each point necessary to fill the inside of the side based on the table (1) for each Y coordinate value forming the polygon ( 2)
Find the X coordinate of the 'pair' to fill in, and calculate the '
In a method that performs surface painting of a figure by outputting each pixel between the X coordinates of the pair, the X coordinates of the pair are stored as an output table (3), and the polygon is formed. A horizontal side table (4) consisting of the X coordinate of the starting point and the X coordinate of the end point of the horizontal side.For each value of the Y coordinate making up the above polygon, search the horizontal side table (4) that intersects with the Y coordinate. The X coordinates of the start point and end point of one horizontal side read out, and the 'pair' in the output table (3) above.
and a logical means (5) for comparing the starting point and the X coordinate of the ending point, and in the logical means (5), the starting point of the horizontal side,
Or smaller than the X coordinate of the end point, the above output table (3)
Count the number of X coordinates of , determine whether the number is "even" or "odd", and calculate the number of X coordinates read from the output table (3) for one horizontal side read from the horizontal side table (4). 'vs'
For the X coordinate of If the judgment result is "odd", the 'pair' X of the output table (3) above is inserted.
Deleting the X coordinates in the output table (3) that exist between the start point and the X coordinate of the end point of the horizontal side is specified for all horizontal sides in the horizontal side table (4). , and the above output table (3) contains the X in the horizontal side table (4).
A horizontal edge drawing method for drawing a figure surface, which is characterized by inserting a coordinate or deleting a specific X coordinate from the output table (3).