Palette control method and system for three-dimensional interactive scene

Abstract

The application is suitable for the technical field of three-dimensional drawing, and provides a palette control method and system for a three-dimensional interactive scene, comprising the following steps: receiving a three-dimensional model drawing instruction, entering a drawing surface selection mode, and receiving a drawing surface click instruction; identifying a model surface block where the click position is located, unfolding the model surface block into a plane to obtain a drawing plane; receiving a drawing instruction, displaying a drawing surface on the drawing plane, and mapping the drawing surface on a corresponding position on the model surface block; and performing control gesture recognition, automatically determining a control subject as a three-dimensional model or a drawing plane when a zoom gesture or a translation gesture is recognized, and automatically determining a rotation axis direction and a rotation axis position when a rotation gesture is recognized. The application converts complex three-dimensional surface drawing into relatively simple two-dimensional plane drawing, so that a user can more easily and accurately control the drawing of lines and patterns, and the accuracy and efficiency of drawing are improved.

Description

Technical Field

[0001] This invention relates to the field of three-dimensional painting technology, specifically to a drawing board control method and system for three-dimensional interactive scenes. Background Technology

[0002] In today's digital design and creative expression field, the application of 3D models is becoming increasingly widespread, covering multiple industries such as industrial design, animation production, game development, and virtual reality. As users' demands for 3D model creation and interaction continue to increase, painting on the surface of 3D models has become an important and challenging functional requirement. Traditional 3D model painting methods typically involve drawing directly on the model surface within 3D software; however, this method has many limitations. Firstly, due to the complex geometry of 3D model surfaces, such as curved surfaces, it is difficult to precisely control the direction of lines and patterns when painting directly on them, resulting in low painting efficiency and poor results. Secondly, during the painting process, if it is necessary to view the 3D model and adjust the perspective (such as rotation, translation, scaling, etc.) to better observe the painting position or overall effect, the current painting command must be interrupted, the corresponding model control command executed, and the painting mode re-entered after the operation is completed. This frequent mode switching severely affects the smoothness and efficiency of painting, causing great inconvenience to users. Therefore, there is a need to provide a canvas control method and system for 3D interactive scenarios, aiming to solve the above problems. Summary of the Invention

[0003] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a drawing board control method and system for three-dimensional interactive scenes, so as to solve the problems existing in the above-mentioned background technology.

[0004] This invention is implemented as follows: a canvas control method for 3D interactive scenes, the method comprising the following steps:

[0005] Receive 3D model drawing instructions, enter drawing surface selection mode, and receive drawing surface click instructions;

[0006] Identify the model facet where the clicked location is located, and unfold the model facet into a plane to obtain a drawing plane;

[0007] The canvas interface is divided into two parts: one part is used to display the 3D model, and the other part is used to display the drawing plane.

[0008] Receive drawing instructions, display the drawing screen on the drawing plane, and map the drawing screen to the corresponding position on the model block;

[0009] The system performs gesture recognition. When a zoom or pan gesture is detected, it automatically determines that the subject being controlled is a 3D model or a drawing plane, and then zooms or pans the subject being controlled.

[0010] When a rotation gesture is detected, the rotation axis direction and position are automatically determined, allowing the 3D model to be rotated and displayed.

[0011] As a further aspect of the present invention: the step of unfolding the model facets into a plane to obtain a drawing plane specifically includes:

[0012] Define a UV space for the model facet, assign a UV coordinate to each point on the model facet, and each UV coordinate corresponds to a 3D coordinate.

[0013] Determine whether the model surface is a plane, a developable surface, or a non-developable surface. Obtain the drawing plane by geometric unfolding the developable surface and by triangular discretization the non-developable surface.

[0014] During the development process, each UV coordinate on the drawing plane is recorded. For non-developable surfaces, the correspondence between the UV coordinates of the vertices of discrete triangles and their three-dimensional coordinates is stored, and the mapping of non-vertice positions is calculated by interpolation.

[0015] As a further aspect of the present invention: when mapping the drawing screen to the corresponding position on the model surface, when mapping the drawing plane corresponding to the non-developable surface, the corresponding three-dimensional vertex is found by using the UV coordinates of the discrete triangle vertices, and then the three-dimensional coordinates of the non-triangle vertex positions are calculated by using the centroid coordinate interpolation.

[0016] As a further aspect of the present invention: the step of automatically determining the control subject as a three-dimensional model or a drawing plane specifically includes:

[0017] Retrieve the gesture recognition image and determine the first position information of the zoom or pan gesture in the gesture recognition image;

[0018] Determine the secondary position information of the 3D model and the drawing plane on the canvas interface;

[0019] Based on the first and second position information, the control subject is determined to be a three-dimensional model or a drawing plane.

[0020] As a further aspect of the present invention: the step of automatically determining the direction and position of the rotation axis specifically includes:

[0021] Retrieve the gesture recognition image and determine the direction of the middle finger in the gesture recognition image, wherein the direction of the middle finger is the direction of the rotation axis;

[0022] Identify the position where the brush stops in the drawing plane and determine the corresponding coordinate position of the brush stop position in the 3D model;

[0023] The position of the rotation axis is determined by the coordinate position and the direction of the rotation axis, and the rotation axis passes through the coordinate position.

[0024] As a further aspect of the present invention: the method also includes a comprehensive display of the painting, the specific steps of which are as follows:

[0025] Receive drawing display instructions and determine the model facet selected by the user;

[0026] Identify the entity where the model facet is located, preserve the entity in the 3D model, and hide other entities;

[0027] The preserved entities are rotated and displayed from all directions.

[0028] Another object of the present invention is to provide a drawing board control system for a three-dimensional interactive scene, the system comprising:

[0029] The 3D model painting module is used to receive 3D model painting instructions, enter the painting surface selection mode, and receive painting surface click instructions.

[0030] The model block flattening module is used to identify the model block where the clicked position is located and flatten the model block into a plane to obtain a drawing plane.

[0031] The canvas interface splitting module is used to divide the canvas interface into two parts: one part is used to display the 3D model, and the other part is used to display the drawing plane.

[0032] The drawing synchronization display module is used to receive drawing instructions, display the drawing screen on the drawing plane, and map the drawing screen to the corresponding position on the model block;

[0033] The zoom and pan control module is used to recognize control gestures. When a zoom or pan gesture is recognized, it automatically determines that the control subject is a 3D model or a drawing plane, so that the control subject can be zoomed or panned.

[0034] The gesture rotation control module is used to automatically determine the direction and position of the rotation axis when a rotation gesture is detected, so that the 3D model can be rotated for display.

[0035] As a further aspect of the present invention: the model surface flattening module includes:

[0036] UV 3D coordinate corresponding unit is used to define a UV space for the model face block, assign a UV coordinate to each point on the model face block, and each UV coordinate corresponds to a 3D coordinate.

[0037] The model surface unfolding unit is used to determine whether the model surface is a plane, a developable surface, or a non-developable surface. The geometric unfolding method is used to obtain the drawing plane for the developable surface, and the triangular discretization method is used to obtain the drawing plane for the non-developable surface.

[0038] The UV coordinate recording unit is used to record each UV coordinate on the drawing plane during the unfolding process. For non-developable surfaces, it stores the correspondence between the UV coordinates of the vertices of discrete triangles and their three-dimensional coordinates, and calculates the mapping of non-vertice positions through interpolation.

[0039] As a further aspect of the present invention: the scaling and translation control module includes:

[0040] The gesture position determination unit is used to retrieve the gesture recognition image and determine the first position information of the zoom or translation gesture in the gesture recognition image.

[0041] Model planar position unit, used to determine the second position information of the 3D model and the drawing plane on the canvas interface;

[0042] The control subject determination unit is used to determine whether the control subject is a three-dimensional model or a drawing plane based on the first position information and the second position information.

[0043] As a further aspect of the present invention: the gesture rotation control module includes:

[0044] A rotation axis direction unit is used to retrieve a gesture recognition image and determine the direction of the middle finger in the gesture recognition image, wherein the direction of the middle finger is the rotation axis direction.

[0045] The coordinate position determination unit is used to identify the position where the brush stops in the painting plane and determine the coordinate position of the brush stop position in the three-dimensional model.

[0046] A rotation axis determining unit is used to determine the position of a rotation axis based on the coordinate position and the rotation axis direction, wherein the rotation axis passes through the coordinate position.

[0047] Compared with the prior art, the beneficial effects of the present invention are:

[0048] By transforming complex 3D surface painting into relatively simple 2D planar painting, users can more easily and precisely control the drawing of lines and patterns, greatly improving the accuracy and efficiency of painting. By dividing the canvas interface into two parts, users can simultaneously observe the overall structure of the 3D model and the specific drawing content on the painting plane, facilitating real-time adjustments and optimizations of the image on the plane based on the overall display effect of the painting on the model. It can automatically determine the control subject and corresponding operation based on the gesture type, enabling interactive control of the model or painting plane without interrupting the painting command, thus improving the smoothness and continuity of painting. Attached Figure Description

[0049] Figure 1 This is a flowchart of a canvas control method used in 3D interactive scenes.

[0050] Figure 2 This is a flowchart for unfolding model facets into a plane in a canvas control method used in 3D interactive scenes.

[0051] Figure 3 This is a flowchart for automatically determining the control subject in a canvas control method used in 3D interactive scenes.

[0052] Figure 4 This is a flowchart for determining the direction and position of the rotation axis in a canvas control method used in 3D interactive scenes.

[0053] Figure 5 This is a flowchart for a canvas control method used in 3D interactive scenes to display the drawing from all angles.

[0054] Figure 6 This is a schematic diagram of the canvas control system used in 3D interactive scenarios. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0056] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0057] like Figure 1 As shown, this embodiment of the invention provides a canvas control method for a three-dimensional interactive scene, the method comprising the following steps:

[0058] S100 receives 3D model drawing instructions, enters drawing surface selection mode, and receives drawing surface click instructions;

[0059] S200: Identify the model block where the clicked location is located, and unfold the model block into a plane to obtain a drawing plane;

[0060] The S300 divides the canvas interface into two parts: one part is used to display 3D models, and the other part is used to display the drawing plane.

[0061] S400, receive drawing instructions, display a drawing screen on the drawing plane, and map the drawing screen to the corresponding position on the model block;

[0062] The S500 performs control gesture recognition. When a zoom or pan gesture is recognized, it automatically determines that the control subject is a 3D model or a drawing plane, so that the control subject can zoom or pan.

[0063] When the S600 recognizes a rotation gesture, it automatically determines the direction and position of the rotation axis, enabling the 3D model to be rotated and displayed.

[0064] It should be noted that traditional methods of drawing directly on the surface of a 3D model are time-consuming, laborious, and inefficient due to the complexity of the model's geometry and the difficulty in precisely controlling the drawing elements. For example, when drawing patterns on complex curved surfaces, lines are prone to distortion and discontinuity, requiring repeated corrections. Furthermore, during the drawing process, when it's necessary to rotate, translate, or scale the 3D model to observe the drawing effect from different angles or adjust its position, the current drawing command must be interrupted, model control commands executed, and the drawing mode re-entered after the operation is complete. This frequent mode switching severely disrupts the continuity and smoothness of the drawing process, degrading the user experience. The embodiments of this invention aim to solve the above problems.

[0065] In this embodiment of the invention, the first step is to complete the modeling of the 3D model in the electronic drawing board. The initial 3D model is a solid, meaning its surface has no painted decorations. Next, painting needs to be done on the surface of the solid 3D model. At this point, the user needs to input 3D model painting commands. The electronic drawing board will enter a painting surface selection mode. The user needs to click on the surface they want to paint on. After the user clicks, the electronic drawing board receives the painting surface click command. It will then automatically identify the model facet where the clicked location is located, that is, identify which facet the user wants to paint on in the model entity. Then, the model facet is unfolded into a plane to obtain a painting plane. In this way, the user can draw on the plane, transforming complex 3D surface painting into relatively simple 2D plane painting, allowing the user to more easily and accurately control the drawing of lines and patterns, greatly improving the accuracy and efficiency of painting. Next, the canvas interface will automatically split into two parts: one for displaying the 3D model and the other for displaying the drawing plane. This allows users to create using various drawing commands. The drawing will be displayed on the drawing plane, and simultaneously mapped to corresponding positions on the model's facets. This allows users to simultaneously observe the overall structure of the 3D model and the specific content drawn on the drawing plane, facilitating real-time adjustments and optimizations to the drawing on the plane based on the overall effect of the drawing within the model. This intuitive display method provides users with more creative ideas and flexibility, helping to create 3D model drawings that better meet their needs and improve design quality.

[0066] Furthermore, to avoid interruptions and ensure smooth drawing, gesture recognition is implemented throughout the drawing process. Specifically, the front-facing camera captures images and identifies the presence of control gestures within them. When a zoom or pan gesture is detected, the system automatically determines the control subject as a 3D model or the drawing plane, causing the subject to zoom or pan. When a rotation gesture is detected, the system automatically determines the rotation axis direction and position, causing the 3D model to rotate. When the gesture disappears, the zoom, pan, or rotation action stops. In this way, the system automatically determines the control subject (3D model or drawing plane) and the corresponding operation (zoom, pan, rotation, etc.) based on the gesture type, enabling interactive control of the model or drawing plane without interrupting the drawing command. This allows users to freely adjust the viewpoint and model position while drawing continuously, observing the drawing effect from different angles, greatly improving the smoothness and continuity of the drawing process, and providing users with a more convenient and efficient creative experience.

[0067] like Figure 2 As shown in the preferred embodiment of the present invention, the step of unfolding the model facets into a plane to obtain a drawing plane specifically includes:

[0068] S201 defines a UV space for the model face block, assigns a UV coordinate to each point on the model face block, and each UV coordinate corresponds to a three-dimensional coordinate.

[0069] S202, determine whether the model surface is a plane, a developable surface or a non-developable surface, and obtain the drawing plane by geometric unfolding the developable surface and by triangle discretization the non-developable surface.

[0070] S203 records each UV coordinate on the drawing plane during the unfolding process. For non-developable surfaces, it stores the correspondence between the UV coordinates of the vertices of discrete triangles and their three-dimensional coordinates, and calculates the mapping of non-vertice positions through interpolation.

[0071] In this embodiment of the invention, to unfold the model blocks into a plane and facilitate subsequent mapping of drawing images onto the model blocks, a UV parameterized mapping relationship needs to be established. Specifically, a UV space is defined for the model blocks, and a UV coordinate is assigned to each point (e.g., each pixel) on the model blocks. Each UV coordinate corresponds to a three-dimensional coordinate. Then, it is necessary to determine whether the model blocks are planes, developable surfaces, or non-developable surfaces. Developable surfaces are those that can be unfolded onto a plane without stretching or tearing. After unfolding, the geometric properties (such as length and angle) of such surfaces remain unchanged. Non-developable surfaces (such as spheres, hyperboloids, etc.) will inevitably undergo stretching or compression deformation when unfolded onto a plane. For developable surfaces, the drawing plane is obtained through geometric unfolding, and for non-developable surfaces, the drawing plane is obtained through triangle discretization. During the unfolding process, for planar blocks and developable surfaces, their three-dimensional coordinates are directly mapped to the UV space; for non-developable surfaces, the correspondence between the UV coordinates of the vertices of discrete triangles and their three-dimensional coordinates is stored, and the mapping of non-vertices is calculated through interpolation. When mapping the drawing screen to the corresponding positions on the model facets, for planar facets and developable surfaces, the UV coordinates are directly converted to 3D coordinates; for non-developable surfaces, it is necessary to find the corresponding 3D vertices through the UV coordinates of the discrete triangle vertices, and then calculate the 3D coordinates of the non-triangle vertex positions through centroid interpolation. For example, if the drawing point is located inside a triangle, interpolation is performed using the UV coordinates and 3D coordinates of the three vertices.

[0072] like Figure 3 As shown in the preferred embodiment of the present invention, the step of automatically determining the control subject as a three-dimensional model or a drawing plane specifically includes:

[0073] S501, retrieve the gesture recognition image and determine the first position information of the zoom or pan gesture in the gesture recognition image;

[0074] S502, determine the second position information of the 3D model and the drawing plane on the canvas interface;

[0075] S503, based on the first position information and the second position information, determine that the control subject is a three-dimensional model or a drawing plane.

[0076] In this embodiment of the invention, in order to automatically identify the control subject desired by the user, the system determines the first position information of the zoom or pan gesture in the gesture recognition image, for example, the first position information is: the gesture is located on the right side of the image. Simultaneously, it determines the second position information of the 3D model and the drawing plane on the canvas interface, for example, the second position information is: the 3D model is located on the left side of the canvas interface, and the drawing plane is located on the right side of the canvas interface. This indicates that the gesture is located on one side of the drawing plane, and in this case, the control subject is the drawing plane.

[0077] like Figure 4 As shown, in a preferred embodiment of the present invention, the step of automatically determining the direction and position of the rotation axis specifically includes:

[0078] S601, retrieve the gesture recognition image, and determine the direction of the middle finger in the gesture recognition image, wherein the direction of the middle finger is the direction of the rotation axis;

[0079] S602, Identify the position where the brush stops in the drawing plane and determine the coordinate position of the brush stop position in the three-dimensional model;

[0080] S603, the position of the rotation axis is determined by the coordinate position and the direction of the rotation axis, and the rotation axis passes through the coordinate position.

[0081] In this embodiment of the invention, to achieve precise control of the rotation movement, the direction of the middle finger in the rotation gesture recognition image is automatically determined. The middle finger in the rotation gesture must be straight and not bent. The direction of the middle finger is determined as the direction of the rotation axis; for example, if the middle finger is horizontal, then the rotation axis is also horizontal. Then, the position where the brush rests in the drawing plane is identified, and the corresponding coordinate position in the 3D model is determined. Next, the rotation axis position is determined using the coordinate position and the rotation axis direction. The rotation axis passes through the coordinate position, thus enabling the rotation axis to be quickly and accurately located.

[0082] like Figure 5 As shown in a preferred embodiment of the present invention, the method further includes a comprehensive display of the painting, the specific steps of which are as follows:

[0083] S701 receives the drawing display instruction and determines the model facet selected by the user;

[0084] S702, Identify the entity where the model facet is located, preserve the entity in the 3D model, and hide other entities;

[0085] S703 allows for a full-range rotating display of the preserved entity.

[0086] In this embodiment of the invention, when the drawing is completed and the user needs to display it in 3D, the user needs to input the drawing display command and click on the model block to be displayed. Then, the system will automatically identify the entity where the model block is located, retain the entity in the 3D model, and hide other entities to avoid visual obstruction of the displayed entity. Finally, the retained entity will be rotated in all directions for display.

[0087] like Figure 6 As shown, this embodiment of the invention also provides a drawing board control system for a three-dimensional interactive scene, the system comprising:

[0088] The 3D model painting module 100 is used to receive 3D model painting instructions, enter the painting surface selection mode, and receive painting surface click instructions.

[0089] The model block flattening module 200 is used to identify the model block where the clicked position is located and flatten the model block into a plane to obtain a drawing plane.

[0090] The canvas interface segmentation module 300 is used to divide the canvas interface into two parts: one part is used to display the 3D model, and the other part is used to display the drawing plane.

[0091] The drawing synchronization display module 400 is used to receive drawing instructions, display the drawing screen on the drawing plane, and map the drawing screen to the corresponding position on the model block.

[0092] The zoom and pan control module 500 is used to recognize control gestures. When a zoom or pan gesture is recognized, it automatically determines that the control subject is a 3D model or a drawing plane, so that the control subject can zoom or pan.

[0093] The gesture rotation control module 600 is used to automatically determine the direction and position of the rotation axis when a rotation gesture is detected, so that the 3D model can be rotated for display.

[0094] In this embodiment of the invention, the model surface flattening module 200 includes:

[0095] UV 3D coordinate corresponding unit is used to define a UV space for the model face block, assign a UV coordinate to each point on the model face block, and each UV coordinate corresponds to a 3D coordinate.

[0096] The model surface unfolding unit is used to determine whether the model surface is a plane, a developable surface, or a non-developable surface. The geometric unfolding method is used to obtain the drawing plane for the developable surface, and the triangular discretization method is used to obtain the drawing plane for the non-developable surface.

[0097] The UV coordinate recording unit is used to record each UV coordinate on the drawing plane during the unfolding process. For non-developable surfaces, it stores the correspondence between the UV coordinates of the vertices of discrete triangles and their three-dimensional coordinates, and calculates the mapping of non-vertice positions through interpolation.

[0098] In this embodiment of the invention, the scaling and translation control module 500 includes:

[0099] The gesture position determination unit is used to retrieve the gesture recognition image and determine the first position information of the zoom or translation gesture in the gesture recognition image.

[0100] Model planar position unit, used to determine the second position information of the 3D model and the drawing plane on the canvas interface;

[0101] The control subject determination unit is used to determine whether the control subject is a three-dimensional model or a drawing plane based on the first position information and the second position information.

[0102] In this embodiment of the invention, the gesture rotation control module 600 includes:

[0103] A rotation axis direction unit is used to retrieve a gesture recognition image and determine the direction of the middle finger in the gesture recognition image, wherein the direction of the middle finger is the rotation axis direction.

[0104] The coordinate position determination unit is used to identify the position where the brush stops in the painting plane and determine the coordinate position of the brush stop position in the three-dimensional model.

[0105] A rotation axis determining unit is used to determine the position of a rotation axis based on the coordinate position and the rotation axis direction, wherein the rotation axis passes through the coordinate position.

[0106] The above description only details the preferred embodiments of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0107] It should be understood that although the steps in the flowcharts of the various embodiments of the present invention are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the various embodiments may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least a portion of the sub-steps or stages of other steps.

[0108] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0109] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the disclosure in the specification and embodiments. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the claims.

Claims

1. A canvas control method for three-dimensional interactive scenes, characterized in that, The method includes the following steps: Receive 3D model drawing instructions, enter drawing surface selection mode, and receive drawing surface click instructions; Identify the model facet where the clicked location is located, and unfold the model facet into a plane to obtain a drawing plane; The canvas interface is divided into two parts: one part is used to display the 3D model, and the other part is used to display the drawing plane. Receive drawing instructions, display the drawing screen on the drawing plane, and map the drawing screen to the corresponding position on the model block; The system performs gesture recognition. When a zoom or pan gesture is detected, it automatically determines that the subject being controlled is a 3D model or a drawing plane, and then zooms or pans the subject being controlled. When a rotation gesture is detected, the direction and position of the rotation axis are automatically determined, allowing the 3D model to be rotated and displayed. The step of automatically determining the control subject as a 3D model or a drawing plane specifically includes: retrieving a gesture recognition image and determining the first position information of the zoom or pan gesture in the gesture recognition image; determining the second position information of the 3D model and the drawing plane on the drawing board interface; and determining the control subject as a 3D model or a drawing plane based on the first and second position information. The steps of automatically determining the direction and position of the rotation axis specifically include: retrieving a gesture recognition image, determining the direction of the middle finger in the gesture recognition image, wherein the direction of the middle finger is the direction of the rotation axis; recognizing the position where the brush stops in the drawing plane, determining the coordinate position corresponding to the position where the brush stops in the three-dimensional model; determining the position of the rotation axis using the coordinate position and the direction of the rotation axis, wherein the rotation axis passes through the coordinate position; The method also includes a full-range display of the painting, with the following steps: receiving a painting display instruction and determining the model facet selected by the user; identifying the entity where the model facet is located, preserving the entity in the 3D model, and hiding other entities; and rotating and displaying the preserved entity in all directions.

2. The canvas control method for a three-dimensional interactive scene according to claim 1, characterized in that, The step of unfolding the model facets into a plane to obtain a drawing plane specifically includes: Define a UV space for the model facet, assign a UV coordinate to each point on the model facet, and each UV coordinate corresponds to a 3D coordinate. Determine whether the model surface is a plane, a developable surface, or a non-developable surface. Perform geometric unfolding on the developable surface to obtain the drawing plane, and discretize the non-developable surface into triangles to obtain the drawing plane. During the development of the plane, each UV coordinate on the drawing plane is recorded. For non-developable surfaces, the correspondence between the UV coordinates of the vertices of discrete triangles and their three-dimensional coordinates is stored, and the mapping of non-vertex positions is calculated by interpolation of the centroid coordinates.

3. The canvas control method for a three-dimensional interactive scene according to claim 2, characterized in that, When mapping the drawing screen to the corresponding position on the model face block, when mapping the drawing plane corresponding to the non-developable surface, the corresponding three-dimensional vertex is found by using the UV coordinates of the discrete triangle vertex, and then the three-dimensional coordinates of the non-triangle vertex position are calculated by using the centroid coordinate interpolation.

4. A drawing board control system for three-dimensional interactive scenes, characterized in that, The system includes: The 3D model painting module is used to receive 3D model painting instructions, enter the painting surface selection mode, and receive painting surface click instructions. The model block flattening module is used to identify the model block where the clicked position is located and flatten the model block into a plane to obtain a drawing plane. The canvas interface splitting module is used to divide the canvas interface into two parts: one part is used to display the 3D model, and the other part is used to display the drawing plane. The drawing synchronization display module is used to receive drawing instructions, display the drawing screen on the drawing plane, and map the drawing screen to the corresponding position on the model block; The zoom and pan control module is used to recognize control gestures. When a zoom or pan gesture is recognized, it automatically determines that the control subject is a 3D model or a drawing plane, so that the control subject can be zoomed or panned. The gesture rotation control module is used to automatically determine the direction and position of the rotation axis when a rotation gesture is detected, so that the 3D model can be rotated for display. The scaling and translation control module includes: a gesture position determination unit, used to retrieve a gesture recognition image and determine the first position information of the scaling or translation gesture in the gesture recognition image; a model plane position unit, used to determine the second position information of the 3D model and the drawing plane on the drawing board interface; and a control subject determination unit, used to determine the control subject as a 3D model or a drawing plane based on the first and second position information. The gesture rotation control module includes: a rotation axis direction unit for retrieving a gesture recognition image and determining the direction of the middle finger in the gesture recognition image, wherein the direction of the middle finger is the rotation axis direction; a coordinate position determination unit for recognizing the pen's resting position in the drawing plane and determining the coordinate position corresponding to the pen's resting position in the three-dimensional model; and a rotation axis determination unit for determining the rotation axis position using the coordinate position and the rotation axis direction, wherein the rotation axis passes through the coordinate position. The system can also display the painting from all angles. The specific steps are as follows: receive the painting display instruction and determine the model block selected by the user; identify the entity where the model block is located, retain the entity in the 3D model and hide other entities; rotate and display the retained entity from all angles.

5. The whiteboard control system for a three-dimensional interactive scene according to claim 4, characterized in that, The model surface flattening module includes: UV 3D coordinate corresponding unit is used to define a UV space for the model face block, assign a UV coordinate to each point on the model face block, and each UV coordinate corresponds to a 3D coordinate. The model block unfolding unit is used to determine whether the model block is a plane, a developable surface, or a non-developable surface. The developable surface is geometrically unfolded to obtain the drawing plane, and the non-developable surface is discretized into triangles to obtain the drawing plane. The UV coordinate recording unit is used to record each UV coordinate on the drawing plane during the unfolding process. For non-developable surfaces, it stores the correspondence between the UV coordinates of the vertices of discrete triangles and their three-dimensional coordinates, and calculates the mapping of non-vertice positions through centroid coordinate interpolation.

Images