CN113362352B

CN113362352B - Method for fusing overlapping profiles based on PLT (product markup language) file

Info

Publication number: CN113362352B
Application number: CN202110624848.1A
Authority: CN
Inventors: 罗立锋; 葛其威; 董辉; 唐旺山; 张成祥; 彭宣聪
Original assignee: Hangzhou Zhanhui Technology Co ltd
Current assignee: Hangzhou Zhanhui Technology Co ltd
Priority date: 2021-06-04
Filing date: 2021-06-04
Publication date: 2022-07-22
Anticipated expiration: 2041-06-04
Also published as: CN113362352A

Abstract

The invention discloses a method for fusing overlapping outlines based on a PLT file, which comprises the following steps: acquiring PLT files of the two cutter-supplemented graph outlines; judging whether the two graphic outlines have an overlapping part or not by utilizing the relation between the line segment and the outlines according to the PLT file, and ending if the two graphic outlines do not have the overlapping part; otherwise, the two graphic outlines are fused. The invention is based on operating the contour composed of points, realizes the integration of two contours with overlapped areas, finally forms a fused contour, and well solves the problem of fusing the overlapped contours after finishing the knife repair process operation.

Description

Method for fusing overlapped contour based on PLT file

Technical Field

The application belongs to the technical field of cutting beds, and particularly relates to a method for fusing overlapping profiles based on PLT files. The method is mainly applied to the contour welding process which avoids graph cutting loss caused by a cutting path at an overlapped part when the closed contour has the overlapped part and combines the overlapped closed contour into one or more contours.

Background

With the rapid development of the machine manufacturing industry and the automation industry, the application of the machine is more and more applied in various industries. As an automatic cutting machine, the cutting machine of the cutting machine brings the benefits of high efficiency and low cost under the condition of ensuring the technological requirements.

The PLT file is a main cutting file of the cutting machine, and the cutting path is stored as point information in the cutting file. Before the cutting machine performs cutting, some pretreatment processes are usually performed to achieve the desired cutting effect, wherein the most common pretreatment process is knife repairing.

The cutter compensation in the pretreatment process of the cutting machine is actually the outward expansion of the cutting path (namely the profile) so as to conform to the thickness of the cutting cutter of the actual cutting machine and ensure the accuracy of the cutting profile. However, after the trimming process is performed on the contour, the cutting paths may overlap, and if the overlapping cutting paths are not processed, the overlapped contour may be cut by the cutting machine.

In the prior art, the problem of processing contour overlapping is basically based on processing of overlapping contours by image pixels, but data points in a PLT file are not pixels, and after the graph in the PLT file is subjected to knife-repairing processing, the overlapped or fused contours in the PLT file cannot be processed by using a processing method of the pixel points.

Disclosure of Invention

The application aims to provide a method for fusing overlapping contours based on PLT files, and efficient and accurate fusion of the overlapping contours is realized.

In order to achieve the purpose, the technical scheme adopted by the application is as follows:

a method for fusing overlapped contours based on PLT files comprises the following steps:

step 1, acquiring two PLT files of the graph contour after tool supplementation;

step 2, judging whether the two graphic outlines have an overlapping part according to the relationship between the line segments and the outlines of the PLT file, and finishing if the two graphic outlines do not have the overlapping part; otherwise, executing the next step;

step 3, carrying out fusion processing on the two graphic outlines, which comprises the following steps:

step 3.1, acquiring all effective intersection points and coincidence outlines contained in the overlapping part of the two graphic outlines;

3.2, respectively inserting all the effective intersection points into corresponding positions of the graphic outlines, and respectively dividing the two graphic outlines into a plurality of small outlines by taking the inserted effective intersection points as dividing points;

3.3, taking the area surrounded by the two graphic outlines as two internal areas, and filtering out small outlines in any internal area;

and 3.4, removing the superposed contour on any one of the two graphic contours on the basis of the two graphic contours after the small contours are filtered out, and obtaining the final cutting contour after fusion and superposition.

Several alternatives are provided below, but not as an additional limitation to the above general solution, but merely as a further addition or preference, each alternative may be combined individually for the above general solution or between several alternatives without technical or logical contradictions.

Preferably, the determining whether there is an overlapping portion between two graphic outlines according to the relationship between the line segment and the outline in the PLT file includes:

step 2.1, two closed graph outlines are obtained based on two PLT files, one of the two graph outlines with a small number of line segments is taken as an outline 1, the other graph outline is taken as an outline 2, the outline 1 is split into independent line segments, and end points of the outline 2 are taken to form a point set;

step 2.2, judging the relation between the line segment and the outline 2 according to the position relation between each point in the point set and each line segment:

step 2.2.1, one line segment in the outline 1 is taken as the current line segment to be judged and is recorded as a line segment l₁And line segment l₁The linear equation of (a) is y-kx + c, and the point set of the contour 2 is taken as { P }_n(x_n，y_n) N is 1 to N, and N is the total number of endpoints of the profile 2;

step 2.2.2, Point P of Point set_n(x_n，y_n) Respectively substituted into line segments l₁To d_n＝kx_n+c-y_n；

Step 2.2.3 according to N d_nJudging the line segment l₁The relationship to the profile 2 is as follows:

1) when N ared_nAll satisfy d_n> 0 or d_nIf < 0, it represents the line segment l₁There is no effective intersection with the contour 2;

2) when N is present and 1 < i.ltoreq.N such that

Then represents the line segment l₁The straight line has an intersection point with the contour 2, and the line segment P in the contour 2 is calculated_iP_i-1And line segment l₁The intersection point T of the straight lines_iJudging the intersection point T according to the vector mode method_iWhether or not it is located on line segment l₁If there is an intersection point T corresponding to i satisfying the condition_iIs located on line segment l₁Upper and not being a line segment l₁The end points of (b) represent line segments l₁There is an effective intersection with the contour 2; otherwise, it represents the line segment l₁No effective intersection point with the contour 2;

3) when N ═ i and 1 < i ≦ N, such that d_iIs equal to 0, and d_i+1，d_i-1All are not 0, and P is judged first_iWhether or not it is on line segment l₁If not, then P_iIs not an intersection point, if at line segment l₁In above, d is determined_i+1/d_i-1If d is greater than 0_i+1/d_i-1Point P if greater than 0_iNot as line segments l₁Valid intersection point with the contour 2, if d_i+1/d_i-1Point P less than 0_iAs a line segment l₁The effective intersection with the contour 2;

4) when N is present and 1 < i ≦ N, such that d_iIs equal to 0 and d_i+10 or so that d_iIs equal to 0 and d_i-1When 0, it represents the point P_iAnd point P_i+1Or represents a point P_iAnd point P_i-1Are all located on line segment l₁On the straight line, the point P is judged according to the vector mode method_iAnd point P_i+1Or a determination point P_iAnd point P_i-1Whether or not it is located on line segment l₁If there is a point P_i、P_i+1Or P_i-1Is located on line segment l₁Upper, then, represents the line segment l₁Overlapping with the contour 2, and taking the overlapped part as an overlapping contour; otherwise, it represents the line segment l₁No coincidence with the contour 2;

step 2.2.4, another line segment in the outline 1 is taken as the current line segment to be judged, namely, the current line segment is marked as a new line segment l₁Repeating the steps 2.2.2-2.2.4 until all line segments in the outline 1 are judged;

and 2.3, if the line segment in the outline 1 is effectively intersected or overlapped with the outline 2, overlapping parts exist in the two graphic outlines, otherwise, the overlapping parts do not exist in the two graphic outlines.

Preferably, the intersection point T is determined by a vector modulo method_iWhether or not it lies on line segment l₁The method comprises the following steps:

line segment l is taken₁Two end points Q of_j(x_j，y_j) And Q_j-1(x_j-1，y_j-1) And an intersection point T_i(x_ti，y_ti)；

Calculating line segment l₁Vector of (2)

Line segment Q_j-1T_iVector of (2)

Line segment P_iP_i_₁Vector of (2)

And a line segment P_iT_iVector of (2)

The following were used:

if it is

And is

Then the point of intersection T_iIs located on line segment l₁Upper, else intersection point T_iNot located on line segment l₁The above.

According to the method for fusing the overlapped contours based on the PLT file, the two contours can be integrated into one contour or a plurality of non-intersected contours, so that the cutter compensation requirement is met, and the overlapped contours cannot be cut and damaged. The method is based on operating the contour consisting of points, and realizes the integration of two contours with overlapped areas, and finally forms a fused contour. Because the outline in the current cut file is composed of points, the prior art fuses the outline based on an image recognition mode, and the image cannot be subjected to processing operation before the image is actually printed to form the PLT cut file, and only can be exported according to the outline of the original image. Therefore, the subsequent knife repair process can only operate on the point file, and the contour fusion after the knife repair is also the operation on the point file, so the existing method is not suitable any more. The method can well solve the problem that the coincident outline is fused after the knife repairing process operation is finished.

Drawings

FIG. 1 is a flow chart of a method for fusing overlapping profiles based on PLT files according to the present application;

FIG. 2 is a schematic view of the front and back of two profile complement cutters in one embodiment of the present application;

FIG. 3 is a schematic representation of two contours prior to blending in one embodiment of the present application;

FIG. 4 is a schematic diagram of two contours after being fused in one embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present application, and not all embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without making any creative effort belong to the protection scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

In one embodiment, a method for fusing overlapping contours based on a PLT file is provided, which solves the problem that a contour fusion method in the prior art cannot be applied to the fusion of graphic contours based on the PLT file.

As shown in fig. 1, the method for fusing overlapping outlines based on PLT files of this embodiment includes:

step 1, obtaining the PLT files of the two cutter-compensated graph outlines.

The PLT file contains points and coordinates in the graph contour (i.e., the cutting path) after the tool is supplemented, and the method of the embodiment completes the fusion based on each point in the two graph contours.

Step 2, judging whether the two graphic outlines have an overlapping part according to the relationship between the line segments and the outlines of the PLT file, and finishing if the two graphic outlines do not have the overlapping part; otherwise, the next step is executed.

When judging whether the two figure outlines have the overlapped part, the method divides one of the two figure outlines into line segments, and judges whether the two figure outlines have the overlapped part by utilizing the relation between each line segment and the other figure outline so as to accelerate the judgment speed.

When calculating the relationship between the line segment and the contour, the method generally adopted in the prior art is to split the contour into line segments, and then to determine whether the intersection point exists between the target line segment and the line segment set of the target contour. The existing judging method not only needs to calculate the linear equation of each line segment in the outline, but also needs to repeatedly take the line segment for judgment, so that the judging efficiency is extremely low. In order to improve the efficiency of judging the relationship between the line segment and the contour, the embodiment provides a method for quickly and effectively determining whether the line segment intersects with the contour by using the relationship between the point and the line segment and finding the intersection point.

In this embodiment, it is defined that if there is an effective intersection point between a line segment and a contour or the line segment and the contour are overlapped, it means that there is an overlapping portion between two graphic contours, where the effective intersection point between the line segment and the contour is understood that the line segment is intersected with but not overlapped with the line segment in the contour, and the intersection point is not an end point of the line segment, and the line segment and the contour are overlapped with each other is understood that the line segment is parallel to and partially or completely overlapped with the line segment in the contour.

Specifically, in this embodiment, determining whether there is an overlapping portion between two graphic outlines according to a relationship between a line segment and an outline in a PLT file includes the following steps:

and 2.1, obtaining two closed graph outlines based on the two PLT files, taking one of the two graph outlines with a small number of line segments as an outline 1, taking the other graph outline as an outline 2, splitting the outline 1 into independent line segments, and taking the end points of the outline 2 to form a point set.

step 2.2.1, one line segment in the outline 1 is taken as the current line segment to be judged and is recorded as a line segment l₁And line segment l₁The linear equation of (a) is y-kx + c, and the point set of the contour 2 is taken as { P }_n(x_n，y_n) N is 1 to N, and N is the total number of endpoints of the contour 2.

Step 2.2.2, Point P of Point set_n(x_n，y_n) Respectively substituted into line segments l₁To d_n＝kx_n+c-y_n。

1) when N is d_nAll satisfy d_n> 0 or d_nIf < 0, it indicates line segment l₁There is no valid intersection with the contour 2.

2) When N is present and 1 < i.ltoreq.N such that

Then represents the line segment l₁The straight line has an intersection point with the contour 2, and the line segment P in the contour 2 is calculated_iP_i-1And line segment l₁The intersection point T of the straight lines_iJudging the intersection point T according to the vector mode method_iWhether or not it lies on line segment l₁If there is an intersection T corresponding to i meeting the condition_iIs located on line segment l₁Upper and not being a line segment l₁The end points of (b) represent line segments l₁There is an effective intersection with the contour 2; otherwise, it represents the line segment l₁There is no valid intersection with the contour 2.

3) When N ═ i and 1 < i ≦ N are present, such that di is 0, and d_i+1，d_i-1If both are not 0, P is judged first_iWhether or not it is on line segment l₁If not, then P_iIf it is not an intersection (or a valid intersection), i.e. a line segment l₁If it is above, d is determined_i+1/d_i-1Whether or not it is greater than 0, if d_i+1/d_i-1Point P if greater than 0_iNot as line segments l₁Valid intersection point with the contour 2, if d_i+1/d_i-1Point P less than 0_iAs a line segment l₁The effective intersection point with the contour 2.

4) When N ═ i and 1 < i ≦ N, such that d_iIs equal to 0 and d_i+10 or such that d_iIs equal to 0 and d_i-1When equal to 0, it represents a point P_iAnd point P_i+1Or represents a point P_iAnd point P_i-1Are all located on line segment l₁On the straight line, the point P is judged according to the method of vector mode_iAnd point P_i+1Or a determination point P_iAnd point P_i-1Whether or not it lies on line segment l₁If there is a point P_i、P_i+1Or P_i-1Is located on line segment l₁Upper, then, represents the line segment l₁Coincides with the contour 2 and takes the weightThe combined part is used as a superposition contour; otherwise, it represents a line segment l₁No coincidence with the contour 2.

Since the two ends of the same line segment are taken from front to back when i sequentially takes points, there exists a repeated judgment, and a unidirectional (forward or backward) cyclic judgment mode is recommended to avoid the repeated judgment, for example, if i in the embodiment takes a value of 1 < i ≦ N, the embodiment is implied to be a backward unidirectional judgment mode, for example, if i is 2, that is, a line segment P is taken₂P₁Judging that the line segment P is taken when i is 3₃P₂Judgment was made, and thus although d is listed in case 4)_i、d_i+1And d_i、d_i-1Two cases, but only one case exists in actual operation (e.g., d of the present embodiment)_i、d_i-1The case).

And at the line taking section l₁Taking the line segment l when the contour is overlapped with the contour 2₁And line segment P_iP_i-1The end point of the other line segment is taken, and the line segment between the two end points is taken as a coincidence outline.

It should be noted that, regarding the relationship between a line segment and an outline, only one of the above 1) to 4) occurs, that is, 1) to 4) are not sequentially required to be executed, but which condition is satisfied to execute which judgment is performed, so that a unique relationship between the line segment and the outline is obtained.

Step 2.2.4, another line segment in the outline 1 is taken as the current line segment to be judged, namely, the current line segment is marked as a new line segment l₁And repeating the steps 2.2.2-2.2.4 until all line segments in the outline 1 are judged.

And 2.3, if the line segment in the outline 1 and the outline 2 have effective intersection points or are overlapped, overlapping parts exist in the two graphic outlines, otherwise, the two graphic outlines do not have the overlapping parts.

It is easily understood that the overlapping part referred to in this application includes intersection and coincidence, and the intersection is that there must be an effective intersection point, so in practical application, if there is intersection and coincidence at the same time, it is necessary to merge the two cases, and if there is only one of the cases, it is only necessary to merge the existing cases.

Wherein, the intersection point T is judged according to the vector mode method_iWhether or not it lies on line segment l₁The method comprises the following steps:

line segment l is taken₁Two end points Q of_j(x_j，y_j) And Q_j-1(x_j-1，y_j-1) And the intersection point T_i(x_ti，y_ti)；

Calculating line segment l₁Vector of (2)

Line segment Q_j-1T_iVector of (2)

Line segment P_iP_i-1Vector of (2)

And a line segment P_iT_iVector of (2)

The following:

if it is

And is

It should be noted that the intersection point T is determined according to the determination_iWhether or not it is located on line segment l₁The vector modulo approach described above can be analogized to accomplish point P_iAnd point P_i+1Or a decision point P_iAnd point P_i-1Whether or not it is located on line segment l₁The above judgment will not be described herein.

and 3.1, acquiring all effective intersection points and coincident outlines contained in the overlapped part of the two graphic outlines.

And 3.2, respectively inserting all the effective intersection points into corresponding positions of the graph outlines, and respectively dividing the two graph outlines into a plurality of small outlines by taking the inserted intersection points as dividing points.

And 3.3, taking the area surrounded by the two graphic outlines as two internal areas, and filtering out the small outline in any internal area.

And 3.4, removing the superposed contour on any one of the two figure contours on the basis of the two figure contours with the small contours filtered out to obtain the final cutting contour after fusion and superposition.

To enhance the understanding of the fusion method of the present application, the following is further illustrated by a specific example:

as shown in fig. 2, the left side of fig. 2 shows the position relationship before the knife compensation of the two graphic outlines, and it can be seen from the figure that there is no overlapping portion between the two graphic outlines, and according to the position relationship after the knife compensation of the two graphic outlines on the right side of fig. 2, it can be seen that there is an overlapping portion between the two graphic outlines after the knife compensation, so that it is necessary to perform the fusion processing on the two graphic outlines.

As shown in fig. 3, in order to facilitate description of adding corresponding letters to each point of two graphic outlines to be fused in the present embodiment, the method for fusing overlapping outlines based on a PLT file in the present embodiment includes:

and step S1, after carrying out tool compensation, acquiring coordinate information of the outlines of the two graphs, and judging whether the two closed graphs have an overlapped part or not by utilizing the relation between the line segment and the outlines.

In step S2, if there is an overlapping portion, the two contours need to be fused. The following provides a specific solution for determining the contour overlap and the contour fusion:

A. judging whether the outlines are overlapped and determining an effective intersection point and an overlapped outline, wherein the specific calculation is as follows:

selecting an outline ABCD (as an outline 1) with fewer line segments, splitting the outline ABCD into four line segments of AB, BC, CD and DA, and sequentially calculating the line segments and the outline P₁P₂P₃P₄P₅P₆P₇P₈P₉(as the intersection of the contours 2). In this example, P is₉And P₁The same end point in the outline 2 can be identified as P when making a decision₁P₂P₃P₄P₅P₆P₇P₈I.e. P can be omitted when computing the subsequent set of points₉And (4) calculating points.

Taking one of the four line segments AB, BC, CD and DA as a line segment l₁Let line segment l₁The equation of the straight line is as follows:

y＝kx+c

contour P₁P₂P₃P₄P₅P₆P₇P₈P₉The point set of endpoints (i.e., N ═ 9) is:

{P_n(x_n，y_n)}，n＝1，2，3，4，5，6，7，8，9

substituting points on the contour into line segment l₁Equation of the line:

d_n＝kx_n+c-y_n

when d is_n0, indicates that the point is on the line segment, when d_n> 0 or d_n< 0 indicates that the point is on one of the two sides of the straight line. Record all d_nValue of canAccording to d recorded_nAnd judging the relation between the line segment and the contour according to the following four conditions:

1) when all d_nAll satisfy d_n> 0 or d_n＜0

Indicating that all points on the contour 2 are on line segment l₁On the same side of the straight line, i.e. line segment l₁The straight line does not have a valid intersection with the contour 2. As shown by line segments AB and DA in FIG. 3, the point sets of the contour are all on the same side of the line on which line segments AB and DA lie, and there is no effective intersection with contour 2, i.e., they do not intersect.

2) When N ═ i and 1 < i ≦ N are present so that

Then the line segment l is represented₁The straight line has an intersection with the contour 2, and the line segment BC in FIG. 3 is taken as the line segment l₁I is 2, calculated

The straight line of the line segment BC has an intersection with the contour 2. Calculating point (x)_i-1，y_i-1) And point (x)_i，y_i) Line segment l of the composition₂(i.e., line segment P)_iP_i-1) The equation of the straight line is as follows:

(x_i-x_i-1)*y-(y_i-y_i-1)*x+x_i-1*y_i-x_i*y_i-1＝0

according to l₂The equation of the straight line and the line segment l₁The equation of the straight line can calculate the intersection point E (x)_e，y_e) (i.e. T)_i(x_ti，y_ti) ) is:

finally, judging whether the intersection point is on the line segment l according to a vector mode method₁Above, here l₁Representing the segment BC, set the segment l₁Two end points Q of_j(x_j，y_j) And Q_j-1(x_j-1，y_j-1) Corresponds to line BC and then is B (x)_b，y_b) And C (x)_c，y_c) Where j is a distinguishing parameter in the expression for distinguishing line segments l₁Two different end points, at line segment l₁After the segment BC is corresponded, j is corresponded to b, and j-1 is corresponded to c. Understanding the intersection point T by the same principle_i(x_ti，y_ti) Coordinate subscript ti in.

The vectors are calculated as follows:

wherein the vector

And

are respectively line segments l₁And vectors of line segments CE, vectors

And

are respectively line segments l₂And a line segment P_iThe vector of E.

If it is

And is

The intersection E is at the line segment l₁And a line segment l₂And the intersection E is not the line segment l₁End points of, i.e. line segments l₁Intersecting the contour 2. If there are a plurality of i such that

Then it is necessary to take each i in turn to perform the above calculation until the line segment l is determined₁All valid intersections with the contour 2, so that if there is a match condition i (i.e. so that

I) corresponding to the intersection point T_iIs located on line segment l₁Upper and not being a line segment l₁The end points of (1) represent line segments l₁There is an effective intersection with the contour 2; if all I meeting the conditions correspond to the intersection point T_iAre not located on line segment l₁Upper represents line segment l₁There is no valid intersection with the contour 2.

By analogy, the line segment BC and the contour P can be calculated₁P₂P₃P₄P₅P₆P₇P₈P₉The intersection points of (A) and (B) are E and F.

3) When N ═ i and 1 < i ≦ N, such that d_iIs equal to 0, and d_i+1，d_i-1Are all different from 0

In this case, P should be judged first_iWhether or not it is on line segment l₁(Note here that it is judged whether or not there is a line segment l₁Instead of determining whether it is on line segment l₁On a straight line), if P_iOut of line segment l₁Upper, then P_iNot of line segment l₁The point of intersection with the contour 2, let alone the effective point of intersection, if P_iOn line segment l₁Upper then remove d_iDirectly determine d_i+1/d_i-1Whether P is greater than 0 or not is judged_iIs a line segment l₁The intersection with the contour 2. Such as line CD and line P in FIG. 3₄P₅And P₅P₆Corresponding to d₅＝0，P₅On line segment l₁And d is₄，d₆In the case where the ratio is not 0,

so P₅Is an invalid intersection, not taken as a line segment l₁The effective intersection point with the contour 2.

4) When N is present and 1 < i ≦ N, such that d_iIs equal to 0 and d_i+10 or such that d_i0 and d_i-1＝0

Represents point P_iAnd point P_i+1Or represents a point P_iAnd point P_i-1Are all located on line segment l₁On the straight line, the above-mentioned vector mode judging method is used to judge that said line segment formed from two adjacent points and line segment l are not identical₁There is an overlap; when any one of the two adjacent points is on the line segment l₁Upper, shows line segment P_iP_i+1Or P_iP_i-1There is an overlap. Dividing the overlapped line segment into overlapped part and non-overlapped part to form 1-3 small line segments, such as side P in FIG. 3₆P₇Overlap with the edge BC, then divide the two edges into BPs₇、P₇C and CP₆Three line segments. When cutting is ensured, the segment P is overlapped₇C cutting once.

B. When the contour fusion is carried out, the contours are recombined according to the effective intersection points and the coincident contours.

The embodiment mainly processes the overlapped contour after the cutter compensation and prevents the contour from being cut. Therefore, at the time of processing, portions included in each other are to be removed.

B1, taking out the overlapped contours separately, and dividing the contours into multiple segments (i.e. multiple small contours) by taking the intersection points as the dividing points. As shown in fig. 3, the overlapping portion is P₇C, then according to the intersection point E, F, the contour CD ABEFP₇Segmentation into CDABE, EF and FP₇A third stage; contour P₁EP₂P₃P₄P₅P₆CP₇P₈FP₉Segmentation into EP₁F，EP₂P₃P₄P₅P₆C and P₇P₈And F, three sections.

When the contours are recombined, the overlapped contours may be taken out separately for fusion according to this embodiment, or the overlapped contours may be deleted after the overlapped contours are taken out separately according to a method provided in another embodiment.

B2, judging the inner segment and deleting

By the original contour P₁P₂P₃P₄P₅P₆P₇P₈P₉Determine contours CDABE, EF and FP for the region₇Three segments. Judging the position of the segment relative to the region, taking the points which are not end points in any segment to judge whether the segment is in the region, if only two end points exist in the segment, taking the middle points of the two end points to judge whether the middle points are in the region. Taking a judgment point as a starting point, taking rays along the direction of an x positive axis, calculating the intersection point of the straight line and the contour, wherein when the number of the intersection points is an even number, the point is outside the contour, and when the number of the intersection points is an odd number, the point is inside the contour; taking the segment CDABE as an example, taking a non-end point D as a ray DC, and calculating to obtain an intersection point P₅C and the line segment P₂P₃Due to P at the intersection of₅Are on one side of the ray, so P₅A non-valid intersection point. There are only two valid intersection points of the ray with the contour and therefore point D is not inside the contour.

The method can calculate according to the method, and the EF can be judged in the internal segment. Again with the outline ABCD as the area,judging the profile P₁EP₂P₃P₄P₅P₆CP₇P₈FP₉The internal segment of the three segments of (2) is EP₁F。

B3, joining external segments

According to the judgment of B2, the outer part has CDABE, FP₇，EP₂P₃P₄P₅P₆C and P₇P₈F. Since the end points of the segments are all the intersection points of the original target contour, the outer segments can be recombined according to whether the end points are the same or not. After the outer contour is recombined, the outer contour CDABEP can be obtained₂P₃P₄P₅P₆And an inner profile P₇P₈F, finally adding the overlapped line segment P₇C. Overlapping the contours after the cutter compensation processing, and obtaining an outer contour, an inner contour and a line segment P connecting the two contours after fusion₇C. The resulting profile, as shown in fig. 4, is the final effective cutting wheel diameter.

This embodiment is mainly directed to the case where the contours overlap after the point pattern contour is trimmed. The fusion of the overlapped contours of the two contours can be quickly and effectively solved.

It should be understood that, although the steps in the flowchart of fig. 1 are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not limited to being performed in the exact order illustrated and, unless explicitly stated herein, may be performed in other orders. Moreover, at least a portion of the steps in fig. 1 may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, and the order of performance of the sub-steps or stages is not necessarily sequential, but may be performed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is specific and detailed, but not to be understood as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, and these are all within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A method for fusing overlapped contours based on PLT files is characterized in that the method for fusing overlapped contours based on PLT files comprises the following steps:

step 1, acquiring two PLT files of the graph outline after knife supplementing;

3.2, respectively inserting all the effective intersection points into corresponding positions of the graph outlines, and respectively dividing the two graph outlines into a plurality of small outlines by taking the inserted effective intersection points as dividing points;

3.4, removing the superposed contour on any one of the two graphic contours on the basis of the two graphic contours with the small contours filtered out to obtain a final cutting contour after fusion and superposition;

wherein, the judging whether the two graphic outlines have an overlapping part according to the relationship between the line segment and the outline of the PLT file comprises the following steps:

step 2.2.1, one line segment in the outline 1 is taken as the current line segment to be judged and is recorded as a line segment l₁And line segment l₁The linear equation of (a) is y-kx + c, and the point set of the contour 2 is taken as { P }_n(x_n,y_n) N is 1 to N, and N is the total number of endpoints of the profile 2;

step 2.2.2, Point P of Point set_n(x_n,y_n) Respectively substituted into line segments l₁To d_n＝kx_n+c-y_n；

1) when N is d_nAll satisfy d_n>0 or d_n<0 represents a line segment l₁No effective intersection point with the contour 2;

2) when n ═ i and 1 are present<i is less than or equal to N such that

Then the line segment l is represented₁The straight line has an intersection point with the contour 2, and the line segment P in the contour 2 is calculated_iP_i-1And line segment l₁The intersection point T of the straight lines_iJudging the intersection point T according to the vector mode method_iWhether or not it lies on line segment l₁If there is an intersection T corresponding to i meeting the condition_iIs located on line segment l₁Upper and not being a line segment l₁The end points of (b) represent line segments l₁There is an effective intersection with the contour 2; otherwise, it represents a line segment l₁No effective intersection point with the contour 2;

3) when n is present, i and 1<i is less than or equal to N, such that d_iIs equal to 0, and d_i+1,d_i-1If both are not 0, P is judged first_iWhether or not it is on line segment l₁If not, then P_iNot the intersection point, if at line segment l₁If it is above, d is determined_i+1/d_i-1Whether or not it is greater than 0, if d_i+1/d_i-1Point P if greater than 0_iNot as line segment l₁Valid intersection point with the contour 2, if d_i+1/d_i-1Point P less than 0_iAs a line segment l₁The effective intersection with the contour 2;

4) when n is present, i and 1<i is less than or equal to N, so that d_iIs equal to 0 and d_i+10 or so that d_i0 and d_i-1When 0, it represents the point P_iAnd point P_i+1Or represents a point P_iAnd point P_i-1Are all located on line segment l₁On the straight line, the point P is judged according to the method of vector mode_iAnd point P_i+1Or a determination point P_iAnd point P_i-1Whether or not it is located on line segment l₁If there is a point P_i、P_i+1Or P_i-1Is located on line segment l₁Upper, then, represents the line segment l₁Overlapping with the outline 2, and taking the overlapped part as an overlapping outline; otherwise, it represents the line segment l₁No overlap with the contour 2;

2. The method for fusing overlapped contours based on PLT files of claim 1, wherein the intersection point T is determined according to a vector modulo method_iWhether or not it is located on line segment l₁The method comprises the following steps:

line segment l is taken₁Two end points Q of_j(x_j,y_j) And Q_j-1(x_j-1,y_j-1) And an intersection point T_i(x_ti,y_ti)；

Calculating line segment l₁Vector of (2)