JPH04247580A - Automatic trace for graphic - Google Patents

Abstract

PURPOSE:To shorten operating time by calculating an intersection when an element to be traced is crossed to another element, and automatically dividing the element at the intersection. CONSTITUTION:The element 4 and a branch point to the element 14 are prepared, and a system is provided with the input of an operator, and when the element 4 is designated as a trace direction, the elements 4-7 are traced successively. Thence, the element 10 whose end-point coincides with the element 9 is selected, however. the element 10-1 and the element 10-2 are generated by dividing the element 10 at the intersection (a) after calculating the coordinates of the intersection (a). and the element 10-1 is traced. When the element 11 is designated as the trace direction, the system, after tracing the element 11 and calculating the coordinates of the intersection (b) of the element 11 and the element 12, automatically generates the element 12-1 and the element 12-2 by dividing at the intersection (b), and when the element 12-1 is designated, the elements 12-1, 13 are traced, then, processing is completed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to automatic tracing of graphics, and more particularly, to automatic tracing for sequentially extracting a plurality of connected elements necessary for a certain process in a mechanical CAD/CAM system.

0002

[Prior Art] Conventionally, this type of auto-trace function automatically traces elements whose end points match from the trace start element to the trace end element when an operator instructs the trace start element, trace end element, and trace direction with a stylus pen, etc. If you follow the target and specify the direction at a branching point, it will automatically trace to the end element.

0003

[Problems to be Solved by the Invention] The above-mentioned conventional auto-trace function traces elements whose end points match, and therefore cannot trace when elements intersect. Therefore, if there are elements that intersect, it is necessary to divide the elements at the intersection in advance, which has the disadvantage that the operation is troublesome.

For example, a shape consisting of five elements (elements 16 to 20) as shown in FIG. 3(a) is represented by the thick line (
When tracing elements such as element 16, element 17-1, element 18, element 19-1), use the element division command to divide element 17 and element 19 into two elements each (element 17-1) before executing the auto trace command. , element 17-2 and element 1
9-1 and 19-2) to form a group of elements with matching end points (FIG. 3(c)).

[0005]

[Means for Solving the Problems] The present invention provides auto-tracing of a figure in which elements whose end points coincide are retrieved by inputting a trace start element, a trace end element, and a trace direction of a figure consisting of a plurality of elements. , if there is a branch where one end of the traced element connects to two other elements, there is a means to continue tracing by inputting the direction of tracing, and if the element to be traced intersects with other elements, It has means for automatically dividing intersecting elements at their intersections.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is an explanatory diagram illustrating an embodiment of the present invention in the order of its processing, and FIG. 2 shows figures to be autotraced in this embodiment.

[0008] In the figure, numbers 1 to 15 indicate element numbers,
One number corresponds to one element. a is element 10
is the intersection of element 11 and element 10-1 and element 10-2
is an element created by dividing element 10 at intersection a. Similarly, b is the intersection of element 11 and element 12, and element 1
2-1 and element 12-2 are elements created by dividing element 12 at intersection b. Moreover, the thick line represents the part where tracing has been completed.

First, when the operator specifies element 1 as the trace start element, element 13 as the trace end element, and element 2 as the trace direction, the system uses the auto trace function to move from trace start element 1 to element 2, element 2 as the element with matching end points. Trace element 3 in order (Figure 1(a))
.

There is now a branch point to element 4 and element 14, so the system waits for operator input. When the operator specifies element 4 as the tracing direction, the system successively traces element 4, element 5, element 6, and element 7 (FIG. 1(b)). Here, too, there is a branch between element 8 and element 14, so when the operator specifies element 8, the system continues to trace element 8 and element 9 (FIG. 1(c)).

Next, the system selects element 10 whose end point coincides with element 9, but after identifying that element 10 intersects element 11 and calculating the coordinates of intersection a, divides element 10 at intersection a. Then, element 10-1 and element 10-2 are generated. Next, the newly generated element 10-1 is traced following element 9 (FIG. 1(d)).

Here, when the operator specifies element 11 as the tracing direction, the system traces element 11, calculates the coordinates of intersection b of element 11 and element 12, divides element 12 at intersection b, and divides element 12 into element 12. -1 and element 12-2
is automatically generated (Figure 1(e)). Here, when the operator specifies element 12-1 as the tracing direction, the system traces elements 12-1 and 13, and the tracing is completed.

[0013]

[Effects of the Invention] As explained above, in the present invention, when an element to be traced intersects with another element during auto-tracing of an element, the intersection is calculated and the element is automatically divided at the intersection. This saves the operator the trouble of dividing elements in advance, which has the effect of shortening operation time.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention in the order of processing.

FIG. 2 is a diagram showing a figure to be automatically traced in the embodiment shown in FIG. 1;

FIG. 3 is a diagram showing conventional graphic auto-tracing.

[Explanation of symbols]

1 to 20 elements a~d　　　　Intersection of elements

Claims (1)

[Claims] [Claim 1] In automatic tracing of a figure in which elements whose end points match are retrieved by inputting a trace start element, a trace end element, and a trace direction of a figure consisting of multiple elements, one end of the traced element is If there is a branch that connects to two other elements, there is a way to continue tracing by inputting the direction of tracing, and if the element to be traced intersects with another element, the intersecting element is automatically traced at the intersection. Auto-tracing of a figure, characterized by having means for dividing.