JPS6131905B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for filling the inside of a line figure in a figure processing apparatus.

Generally, a figure can be painted black by sequentially scanning the screen of the figure and painting the area between the scanning lines intersecting the outline of the figure and the next intersection as black.

However, in this method, as shown in FIG.
2. A figure that includes overlapping outlines 103 cannot be filled in correctly.

Furthermore, since it is necessary to scan the entire screen in order to fill it in, there is a problem in that the processing time becomes long.

It is an object of the present invention to eliminate such drawbacks and to make it possible to fill in any line figure. Furthermore, since the filling operation only requires scanning within the area of the line figure, the processing time is fast.

The principle of the figure filling method according to the present invention will be explained as follows.

Sequentially input the coordinates of a series of consecutive points on a line figure, and perform the following operations on each point. If the contents of the register corresponding to the vertical coordinate Yi of the input points Xi, Yi are empty, the horizontal coordinate Xi of the input point is registered in that register, and the horizontal coordinate Xg is already stored in the corresponding register.
If it contains, the same vertical coordinate Yi as the input point
The bit in the image memory corresponding to the point between the horizontal coordinate Xg in the upper register and the horizontal coordinate Xi of the input point is inverted, and the contents of the corresponding register are erased.

However, for starting points, horizontal points (points with the same vertical coordinates as the previous point), and vertices (points with different signs of changes in vertical coordinates from the previous and following points whose vertical coordinates are not the same), Do not perform any operations.
For the end point, perform the above operation.

The principle described above will be explained using an example. Figure 1
Examples are shown in (i) to (ii). (i) is an example in which the range surrounded by the point sequence of points 1 to 9 is filled in.
Note that the numbers shown in parentheses for each point indicate coordinate values. First, since point 1 (2, 3) is the starting point, no operation is performed. For point 2 (3, 4), the horizontal coordinate value 3 is stored in the register corresponding to the vertical coordinate value 4.
Register. Point 3 (4, 5) has a vertical coordinate change (5-4) from point 2 (3, 4), which is the previous point whose vertical coordinate values are not the same, and point 4 (5, 5, which is the point immediately after it).
4) and the vertical coordinate change (4-5) have different signs, so no operation is performed. Regarding point 4 (5, 4), the register corresponding to vertical coordinate value 4 already contains the horizontal coordinate value 3 at point 2 (3, 4), so the horizontal coordinate value 3 in the register and point 4 ( 5, 4) and the horizontal coordinate value 5 is inverted. Also erases the value in that register. For the following points 5 (5, 3) and 6 (4, 2), register the horizontal coordinates in the register, and then
(3,1) does nothing like point 3 (4,5). point 8 (2,2), point 6 (4,2) and point 8
Perform bit inversion of points 3, 2 between (2, 2), and since point 9 (2, 3) is the end point, be sure to perform the operation to invert points 5 (5, 3) and 9 (2, 3). The bits between the points (4, 3) and (3, 3) are inverted. By the above operations, filling of the range surrounded by the point sequence of points 1 to 9 is completed.

FIG. 1(ii) is an example including protruding line segments (points 2, 3, 4) and horizontal portions (points 5, 6) (points 8, 9, 10). At point 2 (3, 5), horizontal coordinate value 3 is registered in the corresponding register, and since point 3 (3, 6) is a vertex, no operation is performed.

An attempt is made to invert the bits between points 2 and 4 at point 4 (3, 5), but since there is no point between the two points, nothing is actually done. Point 5 (4, 4) registers the horizontal coordinate value 4 in the corresponding register, and points 6
(5, 4) has the same vertical coordinate value as the immediately previous point, point 5 (4, 4), so no operation is performed. Points 7 to 12 are carried out in the same manner as (i) and points 5 and 6.

FIG. 1(iii) is an example where the contour lines overlap. In this case, a figure is formed by the sequence of points 1 (2, 2) to 7 (2, 2) and points 8 (5, 4) to 14 (5, 2).
4) Treat the figure as two figures with the figure consisting of a sequence of points, and operate in the same way as in (i).

Therefore, the apex portion 100, the protruding line segment, 10
1. As described above, it is possible to easily fill in any figure in which horizontal portions 102, overlapping contours 103, etc. are combined.

According to the present invention, the coordinate information of a sequence of points of a line figure developed on horizontal and vertical grid point coordinates is input sequentially, and the vertical change between the current developed point Xi, Yi and the next developed point, and the If the change has the same sign as the previous vertical change that is not zero, access the register corresponding to the vertical coordinate value Yi of the expansion point, and if no coordinate value has already been written to that register, the expansion Write the horizontal coordinate value Xi of the point, delete the coordinate value if the coordinate value , Yi] and invert the information of the image at each point.

An embodiment of an apparatus that specifically implements the figure filling method of the present invention will be described with reference to FIG.

A line figure generator 1 generates coordinate point sequence information of a line figure developed in a two-dimensional image memory 2.
Specifically, the X and Y coordinates of the starting point of one line figure are output from lines 3 and 4, respectively, and the X counter 5
and is set in the Y counter 6. After that, corresponding to the locus of the line figure to be drawn, +1 (1 coordinate to the right), ±0 (keep the same coordinate), -1 (1 coordinate to the left) in the X direction, +1 (1 coordinate upward) in the Y direction. Coordinates) Signals indicating changes in the point sequence coordinates of ±0 (the coordinates remain as they are) and -1 (one coordinate downward) are lines 7, 8, 9, 10, 11, and 1, respectively.
It is output from 2. The X counter 5 and Y counter 6 are up-down counters, and when there is a signal on lines 7 and 10, respectively, the contents of the corresponding counters 5 and 6 are incremented by 1, and conversely, the contents of the corresponding counters 5 and 6 are increased by 1, and vice versa.
When there is a signal at 12, it operates to decrease the contents of the corresponding counters 5 and 6 by 1. These values of the X counter 5 pass through the gate 39, and the values of the Y counter 6 directly become the address of the image memory 2, so by writing bit 1 to the corresponding lattice point on the image memory 2, the line figure is sequentially A sequence of points can be developed as a two-dimensional image. The contents of this image memory 2 can be read out in raster TV scan form and used for applications such as displaying the output on a display, or transmitting it to a terminal such as a facsimile through a transmission line, but the related circuitry is This is a general item and is not particularly illustrated.

Next, a circuit specific to the fill-in method, which is a feature of the present invention, will be explained. The signals of the lines 10, 11, and 12 are Y between the current expansion points Xi, Yi and the next expansion point.
The change in the (vertical) direction is output. On the other hand, in the flip-flops 13 and 14, among the changes in the Y (vertical) direction, the immediately preceding changes other than zero (when the expansion point sequence moves in the horizontal direction) are stored. That is, if the change in the Y direction is zero, the inverter 15 closes the gates 16 and 17 and nothing is set in the flip-flops 13 and 14, but if the change in the Y direction is other than zero, the change is +1. (above), flip-flop 13,
If the change is -1 (down), flip-flop 14 is set. Line 18 has AND gate 1
A signal is present on both line 10 and flip-flop 13 inputting to AND gate 20, or on line 12 and flip-flop 14 inputting to AND gate 20.
A signal is output when both signals are present. In other words, line 18 shows the case where the change in the Y (vertical) direction between the current expansion point and the next expansion point and the previous change in the Y (vertical) direction where the change is other than zero are in the same direction. A signal is output. Note that the flip-flops 13 and 14 are reset (not shown) at the time the starting point information is input, and when a signal indicating the first change in the Y (vertical) direction after the starting point is output to the line 10 or 12. In this case, only flip-flop 13 or 14 is set, and no signal is output to line 18.

On the other hand, the register group 21 is made up of registers whose number is at least equal to the number of grid points in the Y direction, and is erased initially (before one image is developed). In this embodiment, the erase state is a state in which the register is zero, and the X coordinate value written in this register is 1 or more. The contents corresponding to the Y coordinate Yi of the current expansion point are read from this register group 21, and if the contents are in an erased state, that is, zero, a signal is output from the gate 22. At this time, when the signal on the line 18 is output, the signal on the AND gate 23 opens the gate (multiplexer) 24, and the coordinate value Xi of the current expansion point is set in the register group 2.
1 is written to the register corresponding to the Y coordinate value Yi of the current expansion point. Also, this register group 2
If the contents of the register corresponding to the current expansion point of 1 are other than zero, that is, some coordinate value (for example, Xg) has already been written, the inverter circuit 2
Since the signal inverted by 5 is output, if the signal is output to the line 18 at this time, the signal is output to the gate 26.
The flip-flop 27 is set by this operation, and the filling state S is entered. The filling operation is based on the contents of the register corresponding to the current expansion point of register group 21.
Xg is set in the up-down counter 29 through the gate (multiplexer) 28, and at the same time, the register corresponding to the current expansion point of the register group 21 is opened by opening the gate (multiplexer) 30 and writing zero, that is, erasing it. It starts from.

The content Xg set in the counter 29 is compared with the coordinate value Xi of the current expansion point by a comparator 311. From the comparator 31, if Xg<Xi, the line 32, Xg
>Xi, a signal is output on line 33. Since these are added to the UP and DOWN terminals of the counter 29, the counter 29 is counted in a direction that gradually approaches Xi from Xg until the value of the counter 21 becomes equal to Xi and a signal is sent to the line 34. This continues until the flip-flop 27 indicating the filling state S is reset.

While the counter 29 is counting from Xg to Xi, the gate (multiplexer) 35 is opened.
(On the other hand, since the Y counter 6 remains at the current expansion point Yi)
Pixels corresponding to grid points between Xi and Yi are sequentially accessed, their contents are read out, and the contents are written again with the bits of each pixel inverted by an inverter 36.

The operation of each circuit constituting this embodiment has been described above from a functional perspective, and the timing relationship will be supplementarily explained. The circuit of this embodiment operates in a kind of synchronous circuit configuration, for example, when the system clock is
It is assumed that the operation is performed using timings t ₁ , t ₂ , t ₃ , t ₄ , and t ₅ that are divided into five times every 200 ns.

Timing _t1 is input to the line figure generator 1 in a state other than coloring, and after the starting point is set, the point sequence information of the developed figure of lines 7 to 10 is sequentially input to the next development at timing _t1 . The information changes to point information and is output from lines 7 to 10, but the operation is temporarily stopped during the filling state S. gate 1
t ₂ is input to 9 and 20 in a state other than filling, so AND gates 19 and 20
If the AND condition is satisfied, a signal is output on line 18 at timing _t2 . Flip-flop 13,,1
4 is updated at timing _t3 immediately thereafter.

When a signal is output to the line 18, if a signal is output from the gate 22, the signal via the gate 23 opens the gate (multiplexer) 24 and outputs the current expansion point X.
Write the (horizontal) coordinates to the register group 21. After that, at timing t ₄ , X counter 5 and Y counter 6
changes to the value of the next expansion point, and sets the bit corresponding to the next expansion point in the image memory 2 to 1. This is because in a state other than coloring, the inverter 36
The output of is 1. On the other hand, when a signal appeared on line 18,
If no signal is output from the gate 22, the flip-flop 27 is set and the filling state S is reached, and at the same time, the gates (multiplexers) 28 and 3 are set.
0, the up-down counter 29 is inputted at timing t ₃ in the filling state S, so at that point the value Xg of the counter 29 is increased or decreased (+1 or -1) in the direction approaching Xi, The bit in image memory 2 corresponding to Y counter 6 is timing t ₃ (related circuits are omitted)
is inverted and written. Timing of next cycle
At t _1, it is in the filling state S, so the contents of the line figure generator 1, etc. do not change. At timing _t3 , the counter 29 increases or decreases again, and the adjacent bit in the image memory 2 is inverted and written. Similarly, the counter 29 increases or decreases at each cycle timing _t3 ,
Inversion writing is performed sequentially at timing _t5 . When the comparator ₃₁ detects that when the counter 29 is increased or decreased to become equal to the value Xi of the current expansion point of the X counter 5 at timing t3, the flip-flop 27
is immediately reset to a state other than filling. Therefore, at timing _t4 , the X counter 5 and Y counter 6 change to the values of the next expansion point, and the corresponding bits in the image memory 2 are set to 1 at timing _t5 . At timing _t1 of the next cycle, the point sequence information from the line figure generator 1 further changes to information on the next expansion point, and the same operation is repeated one after another.

In this way, the sequence of coordinate points of one line figure is sequentially processed, and after reaching the end point of that line figure (generally a closed polygon), the X, Y coordinates of the starting point of the next line figure are processed again. The process is repeated by setting the value in the X counter 5 and the Y counter 6. Further, when all necessary line figure group processing is completed, all timings t ₁ to t ₅ are stopped, and a cycle is started in which the contents of the image memory 2 are used.

In explaining this embodiment, it should be noted that the image memory 2 and the register 21 are equipped with a readout latch, etc., so that even if new information is written to a certain address, the readout output will immediately change to the new content. There is no such thing.

Furthermore, in order to make the explanation easier to understand, the line figure generator 1 of this embodiment has been described as one in which the coordinates of the starting point and the change point sequence information for each mesh are sequentially output. However, for example, when using a line figure generator that outputs change point sequence information and pen up-down signals for each mesh from the origin, like a signal to a normal XY recorder, the coordinate output line 4 of the starting point ,5 is missing,
Instead, the first (corresponding to the origin) X, Y counters 5, 6
During the pen-up signal, except for the increase/decrease operation of the X and Y counters 5 and 6, the image memory 2
It is sufficient to enable the operation of this circuit only during the pen-down signal without performing any operation including writing bits to the pen-down signal. As another example, when this line figure generator is like a coordinate input tablet and a person composes graphic art by moving a pen on it, generally the The X, Y coordinates of are used as the starting point information, and thereafter, a series of timings t ₁ to t ₅ are performed every time the coordinate values change by one mesh (the interval is generally 1 ms or more).
By adding some circuitry, for example, if the filling state S is caught in between, the timing output will continue to be output during that time and the timing output will be temporarily stopped at timing _t5 immediately after the state changes to a state other than filling. It can be easily achieved.

Furthermore, although this embodiment has been explained using an example of a binary figure (white/black), this filled-in figure is a shaded image or a color image, and therefore each pixel in the image memory 2 is expressed by multiple bits. If so, the binary figure of this embodiment is retransferred to the color image memory according to its color specification, etc., and the operation of inverting the bits of this embodiment is performed, and the information specifying the background and the filled part are specified. This can be easily achieved by replacing the information. Further, the directions such as X, Y, horizontal, and vertical in this embodiment are defined and explained for convenience, and it goes without saying that even if these directions are reversed, there is no change essentially.

As explained above, in this embodiment, the line figure generator 1
By adding a register 21, a counter 29, a comparator 31, and some flip-flops, gates (multiplexers), etc. to the series of circuits of the X and Y counters 5 and 6 that develop the line figure information from the image memory 2 into the image memory 2, It has the advantage that you can easily fill in the shapes.

[Brief explanation of the drawing]

FIGS. 1(i), (ii), and (iii) are drawings for explaining the principle of the figure filling method of the present invention. Second
The figure is a circuit diagram showing an example of a specific implementation circuit for realizing the figure filling method of the present invention. In the figure, 1 is a line figure generator, 2 is an image memory, 5 is an X counter, 6 is a Y counter, 19, 2
0 is an AND gate, 21 is a register group, 22 is a gate, 29 is an up-down counter, 31 is a comparator, a vertex portion 100, a protruding line segment portion 101,
A horizontal portion 102 and an overlap 103 of contour lines are shown.

Claims (1)

[Claims] 1. Coordinate information of a sequence of points of a line figure developed on horizontal and vertical grid point coordinates is input sequentially, and the vertical change between the current developed points Xi, Yi and the next developed point is calculated. ,
If the change has the same sign as the previous non-zero vertical change, the vertical coordinate value of the current expansion point
Access the register corresponding to Yi, and if the coordinate value is not written in the register, write the horizontal coordinate value Xi of the current expansion point, and if the coordinate value Xg has already been written in the register, the coordinate value At the same time as erasing Xg, the image between its coordinate value Xg and the horizontal coordinate value Xi of the expansion point [Xg, Yi and Xi, Yi
A figure filling method characterized by accessing [points between] and inverting the image information of each point. 2. In a device that receives coordinate information of a sequence of points of a line figure developed on horizontal and vertical (hereinafter referred to as XY) grid point coordinates and draws the figure in a two-dimensional image memory, a direction memory that stores the immediately previous changing direction signal other than zero; a gate circuit that detects a match between the Y changing direction signal of the next development point and the direction signal output from the direction memory and outputs a matching signal; and a Y coordinate value. When the contents of the corresponding register of the register group accessed by and outputting the memory contents and the register group accessed by the current expansion point Y coordinate value in response to the coincidence signal are preset values, to the corresponding register. storing an X coordinate value, and when the content of the corresponding register is other than the preset value, setting the content to a counter described below;
and a set circuit that stores the preset value in the corresponding register, a counter that counts from the set value, and a circuit that sequentially controls the value of the counter to count one by one up to the X coordinate value of the current expansion point. and a circuit for inverting information in the two-dimensional image memory that is accessed using the current Y-coordinate value of the expansion point and the X-coordinate value indicated by the counter while performing the counting control. Coloring device.