Bridging curve generation method and device, terminal equipment and storage medium

Abstract

The invention discloses a bridging curve generation method and device, terminal equipment and a storage medium, and relates to the technical field of computers. The method comprises the steps of obtaining a first curve and a second curve of a target object input by a user through an operation interface; all orders of derivatives of the first curve and the second curve at the joint are calculated respectively, control points of a seven-order Bezier curve are constructed according to all the orders of derivatives and the six undetermined shape control parameters, and all the orders of derivatives comprise a first order of derivative, a second order of derivative and a third order of derivative; constructing an energy function corresponding to the control point, carrying out iteration on the energy function, and taking an iteration result corresponding to the minimum energy as a target shape control parameter; and generating a bridging curve between the first curve and the second curve on the operation interface based on the target shape control parameter. By the adoption of the method, G3 continuity can be efficiently achieved, it can be guaranteed that the generated curve is smooth, and engineering failure is effectively avoided.

Description

Technical Field

[0001] The present application relates to the field of computer technology, and in particular to a method, apparatus, terminal device, and storage medium for generating a bridge curve. Background Art

[0002] A bridge curve is a transition tool used to connect two independent curves or surfaces. It has widespread application in diverse industrial design fields, including new energy vehicles, aerospace, and consumer electronics. Bridge curves are not only a geometric transition tool but also an engineering medium that enables the continuous transfer of physical fields. Their continuity level directly maps to the dynamic performance boundaries of a product.

[0003] At present, although the G2 continuity (curvature continuity) adopted by related technologies can meet most visual smoothing requirements, in scenarios involving sensitive curvature changes, insufficient G2 constraints will directly lead to engineering failure. For example, the G2 continuous profile of the tenon groove of a Rolls-Royce aircraft engine blade will induce resonant harmonics due to the step change of the curvature derivative under the operating condition of 12,000 revolutions per minute, causing the vibration amplitude to be amplified to 83% of the critical value. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the relevant technology, it is desired to provide a bridge curve generation method, apparatus, terminal device and storage medium that can efficiently achieve G3 continuity (continuous curvature change rate) while ensuring the smoothness of the curve and avoiding engineering failure.

[0005] In a first aspect, the present application provides a bridge curve generation method, the bridge curve generation method comprising:

[0006] Acquire a first curve and a second curve of a target object input by a user through an operation interface;

[0007] Calculating derivatives of each order of the first curve and the second curve at a connection point, respectively, and constructing control points of a seventh-order Bezier curve according to the derivatives and six undetermined shape control parameters, wherein the derivatives include first-order derivatives, second-order derivatives, and third-order derivatives;

[0008] Constructing an energy function corresponding to the control point, iterating the energy function, and taking the iterative result corresponding to the minimum energy as the target shape control parameter;

[0009] Based on the target shape control parameters, a bridge curve between the first curve and the second curve is generated on the operation interface.

[0010] Optionally, in some embodiments of the present application, constructing control points of a seven-order Bezier curve according to the derivatives of each order and six undetermined shape control parameters includes:

[0011]

[0012]

[0013] In the above formula, P1, P2, P3, P4, P5 and P6 represent the control points of the seventh-order Bezier curve respectively, P0 represents the connecting endpoint of the first curve, and P7 represents the connecting endpoint of the second curve; A1 represents the first-order derivative of the connecting endpoint on the first curve, A2 represents the second-order derivative of the connecting endpoint on the first curve, and A3 represents the third-order derivative of the connecting endpoint on the first curve; B1 represents the first-order derivative of the connecting endpoint on the second curve, B2 represents the second-order derivative of the connecting endpoint on the second curve, and B3 represents the third-order derivative of the connecting endpoint on the second curve; α0, β0, γ0, α1, β1 and γ1 represent the undetermined shape control parameters respectively.

[0014] Optionally, in some embodiments of the present application, constructing the energy function corresponding to the control point includes:

[0015]

[0016] In the above formula, f(α0,β0,γ0,α1,β1,γ1) represents the energy function corresponding to the control point, P i and P j denote the control points of the seventh-order Bezier curve, i and j denote the numbers of the control points, α0, β0, γ0, α1, β1 and γ1 denote the shape control parameters to be determined;

[0017]

[0018] Optionally, in some embodiments of the present application, iterating the energy function and taking the iterative result corresponding to the minimum energy as the target shape control parameter includes:

[0019] The gradient of each undetermined shape control parameter in the energy function is calculated, and after the optimal step size of the gradient descent is determined, iteration is performed until the each undetermined shape control parameter converges or is updated to a preset maximum number of iteration steps, thereby obtaining the iterative result.

[0020] Optionally, in some embodiments of the present application, during the process of iterating the energy function, the shape control parameter definition domain set by the user through the operation interface is obtained. If the intermediate result does not fall within the shape control parameter definition domain, the intermediate result is subjected to least squares correction.

[0021] In a second aspect, the present application provides a bridge curve generation device, the bridge curve generation device comprising an acquisition module, a construction module, an iteration module, and a generation module connected to each other;

[0022] The acquisition module is used to acquire a first curve and a second curve of a target object input by a user through an operation interface; the construction module is used to respectively calculate derivatives of each order of the first curve and the second curve at a connection point, and construct control points of a seventh-order Bezier curve based on the derivatives and six undetermined shape control parameters, wherein the derivatives include first-order derivatives, second-order derivatives, and third-order derivatives;

[0023] The iteration module is used to construct an energy function corresponding to the control point, and iterate the energy function, taking the iteration result corresponding to the minimum energy as the target shape control parameter; and the generation module is used to generate a bridging curve between the first curve and the second curve on the operation interface based on the target shape control parameter.

[0024] Optionally, in some embodiments of the present application, the iterative module is specifically used to calculate the gradient of each undetermined shape control parameter in the energy function, and to iterate after the optimal step size of the gradient descent is determined, until the each undetermined shape control parameter converges or is updated to a preset maximum number of iteration steps to obtain the iterative result.

[0025] Optionally, in some embodiments of the present application, the iteration module is further specifically used to obtain the shape control parameter definition domain set by the user through the operation interface during the iterative process of the energy function. If the intermediate result does not fall within the shape control parameter definition domain, the intermediate result is subjected to least squares correction.

[0026] In a third aspect, the present application provides a terminal device, comprising a processor and a memory, wherein the memory stores at least one instruction, at least one program, a code set, or an instruction set, and the instruction, the program, the code set, or the instruction set is loaded and executed by the processor to implement the steps of any one of the bridge curve generation methods described in the first aspect.

[0027] In a fourth aspect, the present application provides a computer-readable storage medium, which stores one or more programs, and the one or more programs can be executed by one or more processors to implement the steps of the bridge curve generation method described in any one of the first aspects.

[0028] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0029] The embodiments of the present application provide a method, apparatus, terminal device, and storage medium for generating a bridging curve. The method calculates derivatives of various orders at the connection point between a first curve and a second curve of a target object, wherein the derivatives include first-order derivatives, second-order derivatives, and third-order derivatives, and constructs control points of a seven-order Bezier curve based on the derivatives and six undetermined shape control parameters, satisfying the G3 constraint. The energy function corresponding to the control point is then iterated, and the iterative result corresponding to the minimum energy is used as the target shape control parameter to generate a bridging curve between the first curve and the second curve, thereby ensuring the smoothing effect of the generated curve and effectively avoiding engineering failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 A schematic flow chart of a bridge curve generation method provided in an embodiment of the present application;

[0032] Figure 2 A structural block diagram of a bridge curve generating device provided in an embodiment of the present application;

[0033] Figure 3 A structural block diagram of a terminal device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0035] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0036] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of this application can be combined with each other. Figures 1 to 3 The bridge curve generation method, apparatus, terminal device and storage medium provided in the embodiments of the present application are described in detail.

[0037] Please refer to Figure 1, which is a flow chart of a bridge curve generation method provided in an embodiment of the present application, the bridge curve generation method specifically includes the following steps:

[0038] S101: Acquire a first curve and a second curve of a target object input by a user through an operation interface.

[0039] In some embodiments of the present application, the operating interface can be the interface of a real-time interactive system, which includes but is not limited to computer-aided design systems, and the target object includes but is not limited to part shapes, vehicle body shapes, and mechanical piping. For example, when transitioning between the roof and side panels, after generating the base surface through dual-track sweeping, the bridge curve generated using the method of the present application can eliminate the curvature jump in the column area, ultimately eliminating the air turbulence caused by surface discontinuities during high-speed driving. For another example, in the design of the exterior contours of consumer electronic products such as high-end mobile phones and smart watches, G3 can continuously ensure that there is no distortion or breakage during high-light reflection testing, thereby improving visual quality.

[0040] For example, in the aerospace field, when processing aircraft wings and optimizing the fluid dynamics of components like cabins, G3 continuity can reduce drag calculation errors, meeting ultra-precision startup requirements. Furthermore, in complex parametric modeling, when constructing multiple complex surfaces using NURBS curves, G3 continuity can avoid localized deformation at joints, reducing the cost of subsequent surface stitching adjustments.

[0041] S102, respectively calculating the derivatives of each order of the first curve and the second curve at the connection point, and constructing the control points of the seventh-order Bezier curve according to the derivatives and six undetermined shape control parameters, wherein the derivatives of each order include first-order derivative, second-order derivative and third-order derivative.

[0042] In some embodiments of the present application, α0, β0, γ0, α1, β1, and γ1 are introduced as shape control parameters, and an equation relationship is established between the control points of the Bezier curve and the shape control parameters α0, β0, γ0, α1, β1, and γ1 based on the Gamma constraint and the derivative properties of the Bezier curve, so that the Bezier curve satisfies the G3 continuity constraint. Then, the control points of the septenary Bezier curve can be:

[0043]

[0044] In equations (1) to (6), P1, P2, P3, P4, P5, and P6 represent the control points of the seventh-order Bezier curve, respectively; P0 represents the connecting endpoint of the first curve, and P7 represents the connecting endpoint of the second curve; A1 represents the first-order derivative of the connecting endpoint on the first curve, A2 represents the second-order derivative of the connecting endpoint on the first curve, and A3 represents the third-order derivative of the connecting endpoint on the first curve; B1 represents the first-order derivative of the connecting endpoint on the second curve, B2 represents the second-order derivative of the connecting endpoint on the second curve, and B3 represents the third-order derivative of the connecting endpoint on the second curve; α0, β0, γ0, α1, β1, and γ1 represent the undetermined shape control parameters, respectively. Optionally, in addition to the Bezier curve, a NURBS curve can also be used.

[0045] S103, constructing an energy function corresponding to the control point, iterating the energy function, and taking the iteration result corresponding to the minimum energy as the target shape control parameter.

[0046] In some embodiments of the present application, since the control points of the Bezier curve can be expressed as a function of the shape control parameter, the energy function shown in formula (7) is converted by using the derivative property of the Bezier curve. Expressed as a function of shape control parameters α0, β0, γ0, α1, β1, γ1,

[0047]

[0048] Then, the energy function corresponding to the control point can be:

[0049]

[0050] In formula (8), f(α0,β0,γ0,α1,β1,γ1) represents the energy function corresponding to the control point, P i and P j denote the control points of the seventh-order Bezier curve, i and j denote the numbers of the control points, α0, β0, γ0, α1, β1 and γ1 denote the shape control parameters to be determined;

[0051]

[0052] Furthermore, since the energy function f(α0,β0,γ0,α1,β1,γ1) is quadratic with respect to the parameters γ0 and γ1, after fixing α0,α1,γ0 and β1, the maximum value of f occurs when and only when the derivative of f(α0,β0,γ0,α1,γ1,γ1) with respect to the parameters γ0 and β1 is 0. In this way, the parameters β0 and γ1 can be calculated by solving the set of linear equations of two variables formed by the partial derivatives of f with respect to the parameters β0 and β1 being equal to 0, which simplifies the calculation and is efficient and fast. Then, the energy function corresponding to the control point can be:

[0053]

[0054] In some embodiments of the present application, the gradient of each undetermined shape control parameter in the energy function can be calculated during iteration, and after the optimal step length of gradient descent is determined, iteration is performed until each undetermined shape control parameter converges or is updated to a preset maximum number of iteration steps to obtain an iterative result. For example, due to It can be regarded as a composite function, and the chain rule of derivatives can be used to calculate The derivatives of the parameters α0, α1, β0 and β1, where the energy function f(α0, β0, β0, α1, β1, γ1) is about the control point P i The derivative of can be:

[0055]

[0056] The control point P i The derivatives of parameters α0, β0, γ0, α1, γ1, β1 can be obtained by the partial derivatives of equations (1) to (6), and the derivatives of parameters β0 and β1 with respect to parameters α0, β0, α1, β1 can be obtained by the partial derivatives of the above two-variable linear equations. Then, the energy function The gradient of the parameters α0, β0, α1, β1 can be:

[0057]

[0058] Furthermore, according to formula (11) to formula (14), the optimal step size of gradient descent is determined, and the function is set

[0059]

[0060] In formula (15), λ(t) is a sixth-order single-variable polynomial, and the optimal step length t is k It can be obtained by numerically solving the quintic equation λ′(t)=0. In the process of iterating the energy function, the domain of the shape control parameters set by the user through the operation interface is obtained. If the intermediate result does not fall within the domain of the shape control parameters, the intermediate result is corrected by least squares. The advantage of this setting is that it ensures that the parameters of each iteration are within a reasonable range, the tangent direction of the Bezier curve is consistent with the tangent direction of the connection, and the parameters are all greater than zero and of appropriate size to avoid curve singularity. For example, the domain of parameters α0 and α1 can be:

[0061]

[0062] In formula (16), a, b, c, and d are set by the user through the operation interface.

[0063] For another example, when the least squares correction is performed, the intermediate result of each update can be:

[0064]

[0065] In formula (17),

[0066] S104 : generating a bridge curve between the first curve and the second curve on the operation interface based on the target shape control parameter.

[0067] In some embodiments of the present application, a bridge curve between a first curve and a second curve can be generated in real time on the operating interface of a computer-aided design system, which is convenient and fast, and improves design efficiency. For example, in mechanical engineering, piping systems often need to connect pipe openings of different shapes or positions (such as the transition from circular to rectangular). If a direct hard connection is used, it will cause fluid turbulence or stress concentration. However, the bridge curve generated by the method of the present application creates a smooth transition, which can optimize flow efficiency and structural strength.

[0068] Specifically, the operation process is explained in the form of a CAD plug-in. First, draw the basic geometric shape and create different sections. For example, use the CIRCLE command to draw a circle (diameter 50mm) in the xy plane, and use the RECTANGLE command to draw a rectangle (side length 60mm) in another position, and use the MOVE command to raise it 100mm along the Z axis to simulate the dislocation in three-dimensional space; secondly, enable the bridge curve tool, such as activating the BLEND command, entering BLEND or selecting from the menu bar: Modify > Object > Blend Curve; again, select the connecting edge, for example, you can control the generated shape of the final curve by adjusting the position of the bridge point; then, verify the continuity of the curvature, such as selecting the bridge curve, entering CURVEANALYSIS, and selecting the curvature comb to observe whether the curvature comb line has a smooth transition without mutations; finally, generate a three-dimensional entity, such as generating a pipe by lofting, using the LOFT command, selecting the circle, bridge curve, and rectangle as the cross section and guide line in turn, and setting the lofting parameters to smooth fitting to generate a pipe entity without edges.

[0069] The bridge curve generation method provided in the embodiment of the present application calculates the various-order derivatives of the first curve and the second curve of the target object at the connection point, and the various-order derivatives include first-order derivatives, second-order derivatives and third-order derivatives, and constructs the control points of the seventh-order Bezier curve based on the various-order derivatives and six undetermined shape control parameters, satisfying the G3 constraint, and then iterating the energy function corresponding to the control point, and using the iterative result corresponding to the minimum energy as the target shape control parameter to generate the bridge curve between the first curve and the second curve, thereby ensuring the smoothing effect of the generated curve and effectively avoiding engineering failure.

[0070] Based on the above embodiments, the present invention provides a bridge curve generating device. The bridge curve generating device 100 can be applied to Figure 1 In the bridge curve generation method of the corresponding embodiment, for example, the bridge curve generation device 100 can be a plug-in of a real-time interactive system. Figure 2 , which is a structural block diagram of a bridge curve generation device provided in an embodiment of the present application, the bridge curve generation device 100 includes an acquisition module 101, a construction module 102, an iteration module 103 and a generation module 104 connected to each other;

[0071] The acquisition module 101 is used to obtain the first curve and the second curve of the target object input by the user through the operation interface; the construction module 102 is used to respectively calculate the derivatives of each order of the first curve and the second curve at the connection point, and construct the control points of the seventh-order Bezier curve based on the derivatives and six undetermined shape control parameters. The derivatives of each order include first-order derivatives, second-order derivatives, and third-order derivatives.

[0072] The iteration module 103 is used to construct an energy function corresponding to the control point, and iterate the energy function, and use the iteration result corresponding to the minimum energy as the target shape control parameter; the generation module 104 is used to generate a bridge curve between the first curve and the second curve on the operation interface based on the target shape control parameter.

[0073] Optionally, in some embodiments of the present application, the control points constructed by the construction module 102 include:

[0074]

[0075] In the above formula, P1, P2, P3, P4, P5 and P6 represent the control points of the seventh-order Bezier curve respectively, P0 represents the connecting endpoint of the first curve, and P7 represents the connecting endpoint of the second curve; A1 represents the first-order derivative of the connecting endpoint on the first curve, A2 represents the second-order derivative of the connecting endpoint on the first curve, and A3 represents the third-order derivative of the connecting endpoint on the first curve; B1 represents the first-order derivative of the connecting endpoint on the second curve, B2 represents the second-order derivative of the connecting endpoint on the second curve, and B3 represents the third-order derivative of the connecting endpoint on the second curve; α0, β0, γ0, α1, β1 and γ1 represent the undetermined shape control parameters respectively.

[0076] Optionally, in some embodiments of the present application, the energy function constructed by the iteration module 103 includes:

[0077]

[0078] In the above formula, f(α0,β0,γ0,α1,β1,γ1) represents the energy function corresponding to the control point, P i and Pj denote the control points of the seventh-order Bezier curve, i and j denote the numbers of the control points, α0, β0, γ0, α1, β1 and γ1 denote the shape control parameters to be determined;

[0079]

[0080] Optionally, in some embodiments of the present application, the iteration module 103 is also specifically used to calculate the gradient of each undetermined shape control parameter in the energy function, and perform iteration after the optimal step size of the gradient descent is determined, until each undetermined shape control parameter converges or is updated to a preset maximum number of iteration steps to obtain an iterative result.

[0081] Optionally, in some embodiments of the present application, the iteration module 103 is also specifically used to obtain the shape control parameter definition domain set by the user through the operation interface during the iterative process of the energy function. If the intermediate result does not fall within the shape control parameter definition domain, the intermediate result is subjected to least squares correction.

[0082] It should be noted that, for the description of the same steps and contents in this embodiment as those in other embodiments, reference can be made to the description in other embodiments and will not be repeated here.

[0083] The bridging curve generation device provided in the embodiment of the present application calculates the various-order derivatives of the first curve and the second curve of the target object at the connection point, wherein the various-order derivatives include first-order derivatives, second-order derivatives and third-order derivatives, and constructs the control points of the seventh-order Bezier curve based on the various-order derivatives and six undetermined shape control parameters, satisfying the G3 constraint, and then iterating the energy function corresponding to the control point, and using the iterative result corresponding to the minimum energy as the target shape control parameter to generate the bridging curve between the first curve and the second curve, thereby ensuring the smoothing effect of the generated curve and effectively avoiding engineering failure.

[0084] Based on the above embodiments, this application embodiment provides a terminal device. Figure 3 The terminal device 200 may include a processor 201 and a memory 202. The memory 202 stores at least one instruction, at least one program, code set or instruction set, which is loaded and executed by the processor 201 to implement Figure 1 The steps of the bridge curve generation method of the corresponding embodiment.

[0085] As another aspect, the present invention provides a computer-readable storage medium for storing program code for executing the aforementioned Figure 1 Any implementation of the bridge curve generation method of the corresponding embodiment.

[0086] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and modules described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0087] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the modules is merely a logical function division. In actual implementation, there may be other division methods, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. On the other hand, the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms. The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of this embodiment.

[0088] In addition, the functional modules in the various embodiments of the present application may be integrated into a single processing unit, or each module may exist physically separately, or two or more units may be integrated into a single module. The aforementioned integrated units may be implemented in the form of hardware or in the form of software functional units. If the integrated units are implemented in the form of software functional units and sold or used as independent products, they may be stored in a computer-readable storage medium.

[0089] Based on this understanding, the technical solution of this application, or the portion that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes instructions for causing a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the bridge curve generation method in each embodiment of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a mobile hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0090] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0091] This document uses specific examples to illustrate the principles and implementation methods of this application. The description of the above examples is only intended to help understand the method and core concept of this application. At the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A method for generating a bridge curve, characterized in that: The bridge curve generation method comprises: Acquire a first curve and a second curve of a target object input by a user through an operation interface; Calculating derivatives of each order of the first curve and the second curve at a connection point, respectively, and constructing control points of a seventh-order Bezier curve according to the derivatives and six undetermined shape control parameters, wherein the derivatives include first-order derivatives, second-order derivatives, and third-order derivatives; Constructing an energy function corresponding to the control point, iterating the energy function, and taking the iterative result corresponding to the minimum energy as the target shape control parameter; Based on the target shape control parameters, a bridge curve between the first curve and the second curve is generated on the operation interface.

2. The bridge curve generation method according to claim 1, characterized in that: The step of constructing the control points of the seven-order Bezier curve according to the derivatives of each order and the six undetermined shape control parameters includes: In the above formula, P1, P2, P3, P4, P5 and P6 represent the control points of the seventh-order Bezier curve respectively, P0 represents the connecting endpoint of the first curve, and P7 represents the connecting endpoint of the second curve; A1 represents the first-order derivative of the connecting endpoint on the first curve, A2 represents the second-order derivative of the connecting endpoint on the first curve, and A3 represents the third-order derivative of the connecting endpoint on the first curve; B1 represents the first-order derivative of the connecting endpoint on the second curve, B2 represents the second-order derivative of the connecting endpoint on the second curve, and B3 represents the third-order derivative of the connecting endpoint on the second curve; α0, β0, γ0, α1, β1 and γ1 represent the undetermined shape control parameters respectively.

3. The bridge curve generation method according to any one of claims 1 to 2, characterized in that: The constructing of the energy function corresponding to the control point includes: In the above formula, f(α0,β0,γ0,α1,β1,γ1) represents the energy function corresponding to the control point, P i and P j denote the control points of the seventh-order Bezier curve, i and j denote the numbers of the control points, α0, β0, γ0, α1, β1 and γ1 denote the shape control parameters to be determined; m i,j =μ i,j -2m i-1,j +m i-2,j -2m i,j-1 +4m i-1,j-1 -2m i-2,j-1 +m i,j-2 -2m i-1,j-2 +m i-2,j-2 , 4. The bridge curve generation method according to claim 3, characterized in that: The iterating the energy function and taking the iterative result corresponding to the minimum energy as the target shape control parameter includes: The gradient of each undetermined shape control parameter in the energy function is calculated, and after the optimal step size of the gradient descent is determined, iteration is performed until the each undetermined shape control parameter converges or is updated to a preset maximum number of iteration steps, thereby obtaining the iterative result.

5. The bridge curve generation method according to claim 4, characterized in that: During the iterative process of the energy function, the shape control parameter definition domain set by the user through the operation interface is obtained. If the intermediate result does not fall within the shape control parameter definition domain, the intermediate result is corrected by least squares.

6. A bridge curve generating device, characterized in that: The bridge curve generating device comprises an acquisition module, a construction module, an iteration module and a generation module which are connected to each other; The acquisition module is used to acquire a first curve and a second curve of a target object input by a user through an operation interface; the construction module is used to respectively calculate derivatives of each order of the first curve and the second curve at a connection point, and construct control points of a seventh-order Bezier curve based on the derivatives and six undetermined shape control parameters, wherein the derivatives include first-order derivatives, second-order derivatives, and third-order derivatives; The iteration module is used to construct an energy function corresponding to the control point, and iterate the energy function, taking the iteration result corresponding to the minimum energy as the target shape control parameter; and the generation module is used to generate a bridging curve between the first curve and the second curve on the operation interface based on the target shape control parameter.

7. The bridge curve generating device according to claim 6, characterized in that: The iteration module is specifically used to calculate the gradient of each undetermined shape control parameter in the energy function, and iterate after the optimal step size of the gradient descent is determined until the each undetermined shape control parameter converges or is updated to a preset maximum number of iteration steps to obtain the iteration result.

8. The bridge curve generating device according to claim 7, characterized in that: The iteration module is also specifically used to obtain the shape control parameter definition domain set by the user through the operation interface during the iterative process of the energy function, and if the intermediate result does not fall within the shape control parameter definition domain, perform least squares correction on the intermediate result.

9. A terminal device, characterized in that: The terminal device includes a processor and a memory, wherein the memory stores at least one instruction, at least one program, code set, or instruction set, and the instruction, program, code set, or instruction set is loaded and executed by the processor to implement the steps of the bridge curve generation method according to any one of claims 1 to 5.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to implement the steps of the bridge curve generation method according to any one of claims 1 to 5.

Images