JPS6367690A - Sector generator - Google Patents

Abstract

PURPOSE:To quickly paint out a sector by using a coordinate Y in the center of the sector in a figure as a boundary, splitting said arc into partial figures deciding one line segment in the direction of a coordinate X, painting out the partial figures in response to the coordinate Y and obtaining the coordinates of start and end points in the direction of an axis X. CONSTITUTION:A sector splitter 1 splits the sector as symbols P, Q and R show, attains the partial figures, and sets the coordinate Y to partial scopes like y11-y12, y21-y22 and y31-y32. A clipping device 2 receives the partial figure Q, for instance, and a clipping frame, executes logical operations equivalent to 32 classifications, and outputs a resultant output figure Q' to a painting- out device 3. It paints out a having been clipped partial figure, whereby the figure is clipped. Thus hardware is simplified with only a few logical operations without generating coordinates at a point on the boundary of the invisible fan-shaped arc, and simultaneously the sector can be painted out quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a sector generator for clipping a sector and filling the inside thereof.

BACKGROUND OF THE INVENTION An example of fan-shaped filling in a conventional fan-shaped generator will be described below with reference to the drawings.

FIG. 2 is an example showing the classification of fan-shaped occurrences when clipping is performed. In order to apply the 247 case classifications shown in this figure by combining fan-shaped graphic data and clipping frames, it is necessary to prepare in advance to be able to perform logical operations according to many case classifications. . In order to avoid this, a conventional fan-shaped generator is constructed as shown in FIG. That is, the coordinate values of all the points on the boundary line of the input fan shape are calculated by the coordinate calculation device 1, and the output coordinate values are clipped one by one by the clipping device 2 in which the size of the clipping frame is specified, and then the figure filling device Fill in the inside with 3.

Problems to be Solved by the Invention However, in the configuration shown in Figure 3, the coordinates of all the points on the boundary line of the fan shape that are clipped and cannot be seen are also calculated, which results in unnecessary calculations and slows down the generation time. .

In view of the above-mentioned problems, the present invention provides a fan-shaped generating device for filling in fan-shaped shapes at high speed.

Means for Solving the Problems In order to solve the above problems, the sector generator of the present invention divides an input figure using the X coordinate of the center of the sector as a boundary,
Furthermore, a figure dividing device divides the figure into partial figures that include only one line segment in the X-axis direction belonging to the same The system is configured to have a figure filling device that fills in the shapes.

Operation The present invention uses the above-described configuration to simplify the hardware by using only a few logical operations, and to fill the sector at high speed without generating the coordinates of the sector boundary points that are clipped and become invisible. becomes possible.

EXAMPLE Hereinafter, a fan-shaped generator according to an example of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a sector generator according to an embodiment of the present invention. 1 is a sector dividing device, 2 is a clipping device, and 3 is a filling device. 4 is a Y range register that defines the upper and lower limits of the X coordinate, 5 is an X coordinate generator, 6 and 7 are constant registers that store constants for defining the start line or end line of filling, and 8 and 9 are start A functional operator for generating the coordinates of a point on a line or a route; 10 a start line data register for storing the X coordinate at which to start filling; 11 a connecting line data register for storing the X coordinate at which to end filling; 12 1 is a linear generator that generates pixel data between the start and end points of filling; 13 is a frame memory; 14 is an address generator that obtains the address of pixel data on the frame memory 13;
Reference numeral 5 denotes a write controller that controls when pixel data is written into the frame memory 13.

The operation of the fan-shaped generator configured as described above will be described below.

For example, when clipping and painting the sector shown in Fig. 4, the sector dividing device 1 divides the sector into parts like P, Q, and R in the figure, and sets the X coordinates from y11 to y12.
, y21 to y22, and y31 to y32. A clipping device 2 connected to the output of the figure dividing device 1 receives a partial figure, for example Q, and a clipping frame, performs logical operations corresponding to 32 case divisions, clips the figure, and outputs the resulting figure Q. " is output to the filling device 3. The filling device 3 first takes the first clipping output figure Ql', and outputs y23 to
y24 to Y range register 4, constant data necessary to find the start line and end line of the filling boundary, 11:
y=a *x+b; 12: (x - c) books *2 + (y - d
)*Umbrella'l = r car + b2 ;'s (a, b)
, (c, d, r) are set in constant registers 6 and 7, the X coordinate generator 5 sequentially generates the X coordinate between y23 and y24, and the function calculators 8 and 9 generate the X coordinate of the intersection with the boundary. Let them calculate. The functional calculators 8 and 9 are configured to include a microprocessor and are capable of finding a solution to a designated functional form. The outputs of the function operators 8 and 9 are connected to a starting line data register 10 and a connecting line data register 11. The straight line generator 12 generates the coordinates of a line segment between the starting point and the ending point according to the contents of the starting line data register IO and the connecting line data register 11, and transfers the coordinates to the address generator 14. The address generator 14 outputs the output of the linear generator 12, the X coordinate, and the
The address of the frame memory 13 is calculated from the X coordinate output from the coordinate generator 5 and output to the write control circuit 15. The write control circuit 15 writes pixel data into the frame memory 13 and generates a portion of the sector. Subsequently, similar processing is performed on the second clipping output figure Q2'.

Effects of the Invention As described above, the present invention divides a figure into sub-figures with the X-coordinate of the center of the sector as a boundary with respect to the X-coordinate, and further defines one line segment in the X-axis direction. By determining the starting point coordinates and ending point coordinates in the filling X-axis direction in correspondence with the Y coordinate, it is possible to fill in the fan shape at high speed.

[Brief explanation of the drawing]

FIG. 1 shows a diagram of a graphic generation device in an embodiment of the present invention.
Figure 4 is a schematic diagram showing an example of filling in a fan shape. 1... Sector dividing device, 2... Cliffing device, 3... Shape filling device, 4...
... Y range register, 5 ... Y coordinate generator, 6 ... Constant register, 7 ... Constant register, 8 ... Function operator , 9...
Function calculator, 10... Starting line data register, 1
1... Connection data register, 12...
Linear generator, 13... Frame memory, 14.
... Address generation circuit, 15 ... Write control circuit, 1 ... Coordinate calculation device. Name of agent: Patent attorney Toshio Nakao (1 person) Figure 2 (44f) Attack fqx/3 = 2d'hXI) Figure 4

Claims (1)

[Claims] Input graphic data that uniquely defines a fan shape and a rectangular clipping frame, and divide the input shape using the Y coordinate of the center of the fan shape as a boundary, and one line segment in the X axis direction with respect to the Y coordinate.
A sector dividing device that divides into a plurality of partial figures determined by a clipping device that sequentially outputs a plurality of sets of boundary line data of a fill start line in the axial direction and a fill end line in the X-axis direction; A fan shape generating device comprising: a figure filling device that inputs line data and fills in the space between the two boundary lines in the X-axis direction with respect to the Y coordinate of the Y coordinate range.