WO2012037863A1

WO2012037863A1 - Method for simplifying and progressively transmitting 3d model data and device therefor

Info

Publication number: WO2012037863A1
Application number: PCT/CN2011/079727
Authority: WO
Inventors: 董福田
Original assignee: Dong futian
Priority date: 2010-09-20
Filing date: 2011-09-16
Publication date: 2012-03-29
Also published as: CN102044089A; CN102306395A; CN102332179A; CN102332179B; CN102306395B; WO2012037862A1

Abstract

A method of simplifying and progressively transmitting 3D model data and a device therefor. The simplifying method comprises: setting view control parameters corresponding to a view window; analyzing 3D model data according to the view control parameters and obtaining the 3D model data visible in the view window; confirming the 3D model data visible in the view window is the simplified data. The 3D model data simplifying method disclosed in the present invention utilizes pre-set view control parameters to analyze 3D model data, and discards the 3D model data not visible in the view window corresponding to the view control parameters, thereby reducing the data volume transmitted and increasing transmission speed.

Description

The present invention claims to be submitted to the Chinese Patent Office on September 20, 2010, the application number is 201010287543.8, and the invention name is "a three-dimensional model of adaptive tube, progressive transmission and efficient rendering. The method of Chinese patent application priority and submitted to the Chinese Patent Office on December 6, 2010, application number 201010597111.7, the invention name is "a three-dimensional model of adaptive tube, progressive transmission and rapid drawing method" Priority of the Chinese Patent Application, the entire contents of which is incorporated herein by reference. Technical field

The present invention relates to the fields of spatial information technology, computer graphics, virtual reality technology, and computer operating systems, and more particularly to a three-dimensional model data cylinder, progressive transmission method and apparatus. Background technique

The model is an abstraction or simulation of various laws or processes in the objective world. The spatial data model is an abstraction of spatial entities and their interconnections in the real world. It is the basis for describing and organizing spatial data and designing spatial database patterns. In computer graphics, three-dimensional objects are usually described using a three-dimensional spatial data model (a three-dimensional model), which is then displayed by a computer or other video device. The displayed 3D model can be a real-world entity or a fictional thing that can be as small as an atom or as large as a large size. Anything that exists in physics and nature can be represented by a three-dimensional model.

The 3D model consists of two parts, geometry and texture. Among them, the geometric part is mainly divided into three types: a vector model based on a vector, a solid model based on a voxel, and a mixed model.

The vector-based surface model can also be called vector model, panel model or surface model. It mainly aims at the object boundary and realizes the complete and explicit interface description method by defining and describing the external geometry of the object.

For example, a polygon is used to express a geometric part of a vector-based surface model, that is, a polygon is used to represent or approximate a surface of an object. Its basic object is the vertices in three-dimensional space. The line connecting two vertices is called an edge. The three vertices are connected by three sides to form a triangle. The triangle is the most single polygon in Euclidean space. Multiple triangles can make up a more complex polygon, or a single object that produces more than three vertices. Quadrilaterals and triangles are the most commonly used shapes in a three-dimensional model of polygon expression. In terms of the expression of a three-dimensional model, a three-dimensional model of a triangulation (or TIN model) is due to its data knot. The uniqueness of the stencil and easy drawing by all graphics hardware devices has become a popular choice for 3D model expressions, where each triangle is a surface, so the triangle is also called a triangular patch. At the same time, with the advent of 3D scanning technology and its continuous development and maturity, point cloud has become one of the main means of representation of 3D models.

The voxel-based entity model is also called voxel model, solid model or mosaic model. Based on 3D space voxel segmentation and true 3D entity representation, voxel attributes can be independently described and stored, where voxel model, octree Models and tetrahedral grid models are the three most common models.

Hybrid models, also known as integrated models or integrated models, aim to combine the advantages of multiple models and complement each other.

Many 3D models need to be covered with textures, and the process of placing textures onto a 3D model is called texture mapping. Texture is an image, but it makes the model more detailed and looks more realistic.

With the continuous advancement of science and technology, more and more applications to computer graphics, virtual reality, urban planning, cultural relics, animation games, computer-aided design, geographic information systems, medical graphics, etc. have been applied to three-dimensional graphics. The demand for applications has led to the development of acquisition technology, such as airborne laser scanning, high-resolution satellite imagery, 3D digital camera and scanning systems. These efficient spatial data acquisition methods make the generation of high-resolution 3D models a reality, but It also makes the data volume of the 3D model data grow geometrically. Because the surface detail of a three-dimensional object often requires texture

(Texture-Compression, also known as material) to achieve, then the higher the resolution, the more natural the texture is, the stronger the natural expression is. The higher the resolution (or high precision) of the 3D model, the 3D model. The more textures you need, the larger the amount of data, and the longer it takes to draw. At the same time, the Internet has become a basic platform for data sharing, distributed storage, distributed computing, transmission, visualization, etc., so the 3D models required by a system may be distributed and stored in heterogeneous environments, but the current network transmission bandwidth. It is far from satisfying the real-time transmission of these 3D model data. In the present invention, data for representing, describing, and recording three-dimensional information is collectively referred to as three-dimensional model data, such as three-dimensional spatial data, geometric data and texture data of a three-dimensional model, and corresponding attribute data, and the like.

In the 3D GIS (Geographic Information System) engine, the real-time performance of browsing is very high. If the raw 3D model data is directly downloaded and used, the data transmission speed is very slow. Therefore, improving the transmission efficiency of 3D model data becomes an urgent need. solved problem. Summary of the invention

In view of this, the present invention provides a three-dimensional model dataization cylinder, a progressive transmission method and apparatus. The specific plan is as follows:

A three-dimensional model data cylinder method includes:

Setting a view control parameter corresponding to the view window;

And analyzing the three-dimensional model data according to the view control parameter, and acquiring the three-dimensional model data visible in the view window;

Determining the three-dimensional model data visible in the view window as post-synaptic data.

A three-dimensional model data cylinder device includes:

a parameter setting module, configured to set a view control parameter corresponding to the view window, where the view control parameter includes at least: an outsourcing rectangle, a view point parameter, and a projection parameter of the view window;

An analysis obtaining module, configured to analyze the three-dimensional model data according to the view control parameter, and obtain three-dimensional model data visible in the view window;

And a determining module, configured to determine the three-dimensional model data visible in the view window as post-initial data.

A method for progressive transmission of three-dimensional model data, comprising:

When the incremental data needs to be requested, the requesting sender sends an incremental data request, where the incremental data request includes at least a view control parameter, and the view control parameter includes at least: a current view control parameter; And the incremental data is that the request receiving end analyzes the three-dimensional model data according to the view control parameter, acquires three-dimensional model data visible in a view window corresponding to the current view control parameter, and controls according to the view The parameters were obtained after analysis.

Receiving an incremental data request sent by the requesting sender, where the incremental data request includes at least a view control parameter, and the view control parameter includes at least: a current view control parameter;

And analyzing the three-dimensional model data according to the view control parameter, and acquiring the three-dimensional model data visible in the view window corresponding to the view control parameter;

Determining that the three-dimensional model data visible in the view window is data after the cylinder; The data after the cylinder is analyzed, and the three-dimensional model data that meets the incremental condition is determined to be incremental data; and the incremental data is sent to the request sending end.

A three-dimensional model data progressive transmission device, comprising:

a request sending module, configured to: when the incremental data needs to be requested, the requesting end sends an incremental data request, where the incremental data request includes at least a view control parameter, and the view control parameter includes at least: a current view control parameter;

An incremental data receiving module, configured to receive incremental data sent by the request receiving end, where the incremental data is used by the request receiving end to analyze the three-dimensional model data according to the view control parameter, and obtain the corresponding control parameter in the current view. The 3D model data visible in the view window is obtained after analysis based on the view control parameters.

A three-dimensional model data progressive transmission device, comprising:

a request receiving module, configured to receive an incremental data request sent by the requesting sender, where the incremental data request includes at least a view control parameter, where the view control parameter includes at least: a current view control parameter;

An acquiring module, configured to analyze the three-dimensional model data according to the view control parameter, and obtain three-dimensional model data that is visible in a view window corresponding to the view control parameter;

a determining module, configured to determine that the three-dimensional model data visible in the view window is post-initial data;

An analysis module, configured to analyze the data after the cylinder, and determine the three-dimensional model data that meets the incremental condition as incremental data;

An incremental data sending module, configured to send the incremental data to the request sending end.

It can be seen from the above technical solution that the three-dimensional model data cylinder method disclosed in the embodiment of the present invention analyzes the three-dimensional model data by using preset view control parameters, and is invisible under the view window corresponding to the view control parameter. The 3D model data is discarded, which reduces the amount of data during data transmission and improves the data transmission speed.

Further, since the data of the chemical cylinder is data that is not visible in the view window, the display effect of the three-dimensional model data is not changed, and the lossless display of the data after the chemical cylinder is realized. DRAWINGS In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description It is merely some embodiments of the present invention, and those skilled in the art can obtain other drawings according to these drawings without any creative work.

FIG. 1 is a flowchart of a method for digitizing a three-dimensional model data cylinder according to an embodiment of the present invention; FIG. 2 is a schematic diagram of analyzing three-dimensional model data according to the view control parameter according to an embodiment of the present invention, and obtaining the visible in the view window. Flow chart of the process of 3D model data;

FIG. 3 is a flowchart of a process for analyzing three-dimensional model data according to the view control parameter according to the embodiment, and discarding the three-dimensional model data of the three-dimensional model data that is occluded by other three-dimensional model data in the three-dimensional model;

4 is a flowchart of a process of analyzing three-dimensional model data according to the view control parameter and discarding three-dimensional model data occluded by three-dimensional model data of other three-dimensional models according to the view control parameter according to an embodiment of the present invention;

FIG. 5 is a flowchart of a process for analyzing three-dimensional model data according to the view control parameter and acquiring three-dimensional model data visible in the view window according to an embodiment of the present disclosure;

FIG. 6 is a flowchart of a process for performing a three-dimensional model of a triangulation network according to an embodiment of the present invention; FIG. 7 is a flow chart of a process for preprocessing a three-dimensional model of a triangulation network according to an embodiment of the present invention;

FIG. 8 is a flowchart of a process for implementing the three-dimensional model data according to the result of the blanking analysis according to an embodiment of the present disclosure;

FIG. 9 is a flowchart of determining data of the three-dimensional model data visible in the view window as a post-initiator according to an embodiment of the present invention;

10 is a schematic structural diagram of a three-dimensional model dataization cylinder device according to an embodiment of the present invention; FIG. 11 is a flowchart of a three-dimensional model data progressive transmission method according to an embodiment of the present invention; FIG. 13 is a flowchart of still another three-dimensional model data progressive transmission method disclosed in the embodiment of the present invention; FIG. 14 is a flow chart of another three-dimensional model data progressive transmission method disclosed by the embodiment of the present invention; FIG. 15 is a flowchart of still another method for progressive transmission of three-dimensional model data disclosed in an embodiment of the present invention; FIG. 16 is a schematic diagram of a structure of a three-dimensional model data progressive transmission device according to an embodiment of the present invention; Figure

FIG. 17 is a schematic structural diagram of still another three-dimensional model data progressive transmission apparatus according to an embodiment of the present invention. detailed description

BRIEF DESCRIPTION OF THE DRAWINGS The technical solutions in the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without the creative work are all within the scope of the present invention.

The display process of the 3D model in the view window is generally: firstly, the 3D model conforming to the given spatial condition is taken out through the spatial data index and transmitted to the 3D model user (such as the client) through the transmission medium; and then the 3D model data is performed. After the coordinate transformation and processing of the series, it is transformed into coordinate points on the two-dimensional image; according to the display parameters, the three-dimensional model is finally rasterized into image pixels by a drawing algorithm, drawn into a raster image, displayed or output on the client (such as a computer Screen display, printout on paper, and generation of image file output, etc.). The rendering of the 3D model is ultimately reduced by the drawing algorithm to the operation of one pixel.

Therefore, the present invention proposes to study the adaptive tube and progressive transmission of the three-dimensional model from the perspective of the view (the abstraction of the display output device), and thoroughly solve the problem of network transmission and display of the massive three-dimensional model data.

The invention is based on the following principle: In the case of the view angle, in the case where the resolution of the view window finally used for display is determined, the total number of pixels that the view window can display is fixed, regardless of the massive amount of three-dimensional model data, for final transmission or The maximum visible 3D model data required for display is constant, ie the visible 3D model data required to fill all the pixels of the view window is constant. Because the 3D model is displayed in the view window:

(1) If the drawn 3D model is completely occluded by other drawn 3D models, the 3D model may not be transmitted and mapped;

(2) If the drawn 3D model is partially obscured by other drawn 3D models, and the occluded part cannot be displayed in the view window, the blocked part of the 3D model may not be transmitted and drawn; (3) The 3D model itself may also have occlusion (for example, when the 3D model is displayed, some of the surfaces obscure the other part of the surface), the blocked part of the 3D model can be transmitted and plotted.

The three-dimensional model that we can display after drawing the pixels in the view window is called a visible three-dimensional model. The data used to express the visible part of the three-dimensional model is called visible three-dimensional model data.

The flow of a three-dimensional model dataization cylinder method disclosed in the embodiment of the present invention is as shown in FIG. 1, which includes:

Step S11: Set a view control parameter corresponding to the view window, where the view control parameter includes at least: an outsourcing rectangle, a view point parameter, and a projection parameter of the view window;

The view control parameters include: an outer bounding rectangle of the view window, a viewpoint parameter and a projection parameter; the viewpoint parameter includes a position ⁶ ^ of the viewpoint in the world coordinate system. , ³⁷ . , ² . ), where ^. , ² . Indicates the three components of the viewpoint in the world coordinate system, and the target position observed by the viewpoint ^^,^. ) and the virtual camera up vector "^^, , ) _; a transformation matrix can be determined by the viewpoint parameter, and the coordinates of the vertex in the original coordinate system are transformed into the viewpoint coordinate system. The projection parameters include: orthogonal projection and perspective projection. It is the view matrix and projection matrix obtained by the above parameters.

The view control parameters are determined based on the view window for displaying the three-dimensional model data. Therefore, the data processed according to the view control parameter can meet the requirements in the displayed view window, so as to ensure that the three-dimensional model data after the chemical cylinder is displayed in the actual display window without loss, and the three-dimensional model data after the chemical cylinder is ensured. The correct display of the spatial relationship.

Step S12: Analyze the three-dimensional model data according to the view control parameter, and obtain the three-dimensional model data visible in the view window;

The 3D model data that is invisible under the view window corresponding to the preset view control parameter is removed, and only the visible 3D model data is transmitted to the client through the network, thereby reducing the amount of data in the data network transmission process. At the same time, since the removed 3D model data is not visible under the view window, the data after the cylinder does not change the display effect of the original data, and the lossless display of the data after the cylinder is ensured.

In computer graphics, the use of computers to generate real-world graphics of three-dimensional objects is an important part of computer graphics research. Real graphics are widely used in many fields such as simulation, geometric modeling, advertising, film and scientific computing visualization. When displaying a graphic of an object with a display device, three-dimensional The information is transformed on a two-dimensional display plane after some projection transformation. Since the projection transformation loses depth information, it often leads to the ambiguity of the graphics. To eliminate this kind of ambiguity, you must eliminate the occluded invisible lines, faces, or bodies when drawing. It is customarily called to eliminate hidden lines, hidden faces, hidden bodies, etc., or the cartridge is called blanking. Therefore, in this embodiment, the three-dimensional model data that is not visible in the view window corresponding to the set view control parameter is removed by using a blanking algorithm in computer graphics, and the three-dimensional model data is binarized.

According to the space where blanking is located, the blanking algorithms are usually divided into three categories:

(1) Blanking algorithm for object space: Object space is the three-dimensional space in which a user defines a three-dimensional shape, that is, the world coordinate system space. It is the space in which the three-dimensional shape has not been projected into the two-dimensional space. According to the geometric relationship of the three-dimensional model of each object in the space, compare each face in the scene with each other face, and find the occlusion relationship of all points, edges, faces, and bodies, such as ray casting algorithm, backface culling algorithm, table priority Algorithm, Roberts algorithm, etc.

(2) Image space blanking algorithm: Image space is a two-dimensional space into which a three-dimensional model is projected, that is, what we call a screen space. Each pixel on the screen is judged to determine which polygon is visible in the pixel, such as the scan line algorithm, the Z-buffer algorithm (ie, the depth buffer algorithm), and the like.

(3) Blanking algorithm for object space and image space: Pre-calculate the visibility priority of the surface in the object space, and then generate the blanking map in the image space. In theory, the object space method is that an object must be compared to other objects in the space to determine if it is visible. The image space method is to decompose the projection of each object into pixels, and compare the pixels.

Step S13: Determine that the three-dimensional model data visible in the view window is post-synaptic data. The data obtained after the processing in step S12 is the data after the cylinder.

The three-dimensional model data cylinder method disclosed in this embodiment reduces the data by using the preset view control parameters to analyze the three-dimensional model data, and the three-dimensional model data that is invisible under the view window corresponding to the view control parameter is discarded. The amount of data in the transmission process increases the data transmission speed.

Further, since the data of the chemical cylinder is data that is not visible in the view window, the display effect of the original three-dimensional model data is not changed, and the lossless display of the data after the chemical cylinder is realized.

In the above embodiment, in order to implement the data of the three-dimensional model data, a number of blanking methods are enumerated. The following uses the Roberts algorithm as an example to analyze the three-dimensional model data according to the view control parameters, and obtain the visible in the view window. The process of 3D model data is described in detail, and its process is as shown in the figure. 2, including:

Step S21: analyzing the three-dimensional model data according to the view control parameter, and discarding the three-dimensional model data of the three-dimensional model data that is occluded by other three-dimensional model data in the three-dimensional model in which the data is located;

The 3D model data of the 3D model data occluded by other 3D model data in the 3D model in which it is located is eliminated, that is, the faces and edges of the 3D model that are occluded by itself, that is, the faces of the 3D model that face away from the viewpoint and the related edges. For example, the three-dimensional model A includes a plurality of three-dimensional model data Al, A2, A3, etc., and if A1 is occluded by A2 in the three-dimensional model A, Al is discarded.

Step S22: Analyze the three-dimensional model data according to the view control parameter, and discard the three-dimensional model data of the three-dimensional model data that is occluded by the three-dimensional model data of the other three-dimensional model;

The three-dimensional model data occluded by the data of other three-dimensional models is discarded in the three-dimensional model data. For example, if the three-dimensional model data A1 in the three-dimensional model A is occluded by the three-dimensional model data B1 in the three-dimensional model B, A1 is discarded.

Step S23: Determine, according to the view control parameter, the three-dimensional model data in the remaining three-dimensional model data that is visible in the view window as the post-booster data.

After the above two steps, the remaining three-dimensional model data is three-dimensional model data without occlusion between each other, and then three-dimensional model data without occlusion between each other is analyzed by using view control parameters, and the corresponding control parameters are discarded. The 3D model data that is not visible in the view window determines the 3D model data visible in the view window as the post-booster data.

Specifically, the process of analyzing the three-dimensional model data according to the view control parameter and discarding the three-dimensional model data occluded by the other three-dimensional model data in the three-dimensional model of the three-dimensional model data is as shown in FIG. 3, and includes:

Step S31, determining that any one of the polyhedrons of the three-dimensional model is a current to-be-processed surface, and determining that any point on the current to-be-processed surface is a test point;

Step S32: Calculate an angle between a line of sight vector obtained by the test point according to the viewpoint parameter and an outer plane normal vector of the test point;

Suppose that the outer polygon plane normal vector of the test point on the plane is ηι, and the line of sight vector obtained by the point according to the viewpoint parameter is Si, and the quantity product of the two is: ni-Si= |ni| |Si|cos9i, 0<θι<π

Thus there is

Cc ^ n. s -..

Θι is the angle between ni and si, i=l , 2 , m, where the three-dimensional model corresponds to the number of planes of the polyhedron.

When cos9i > 0, that is, 0 ≤ θι ≤ π/2, it is visible toward the front;

When cos0i < 0, that is, π/2 < θι ≤ π, it is invisible to the back.

Step S33, determining whether the cosine of the angle is greater than or equal to 0, and if so, executing step S34a, and if not, executing step S34b;

Step S34a, determining that the current to-be-processed surface is visible, and performing step S35;

Step S34b, determining that the current to-be-processed surface is invisible, and the invisible three-dimensional model data corresponding to the current to-be-processed surface is discarded, and step S35 is performed;

Step S35: Determine whether there is an unprocessed surface on the three-dimensional model, and if yes, execute step S36, and if no, end;

In step S36, it is determined that the next unprocessed surface is the current to-be-processed surface, and any point on the current to-be-processed surface is a test point, and the process returns to step S32.

According to the above steps, the occlusion relationship between the faces in the three-dimensional model is analyzed, the visible surface and the invisible surface are determined, and then the invisible surface is discarded, thereby occluding the three-dimensional model data of the three-dimensional model in the three-dimensional model data. The 3D model data is discarded.

At the same time, according to the view control parameter analysis 3D model data, the specific process of the 3D model data occluded by the 3D model data of the other 3D model data is shown in FIG. 4, and includes:

Step S41, sorting the three-dimensional model data in order of distance and near distance; step S42, sequentially analyzing the three-dimensional model data in order of near and far, and occluding the occluded after analyzing the three-dimensional model data. Live 3D model data.

According to the distance of the viewpoints, the three-dimensional model data occluded between the three-dimensional models is sequentially processed. For example, the process of eliminating hidden lines of a 3D model is: Starting from the farthest object, for each 3D model, such as 3D model A, checking and determining the occlusion relationship with each of the other 3D models (such as 3D model B) and calculating Hidden lines, first determine whether the enclosing areas of the two-dimensional model on the projection plane intersect, if there is no intersection, there is no occlusion relationship; otherwise, first determine and record whether the two-dimensional model has a mutual penetration relationship in the two coordinate axes of the projection plane And then, for each ridgeline of the three-dimensional model A, by calculating and detecting the intersection of each polygon of the three-dimensional model B on the projection plane, to determine the line segment of the ridge line that is blocked by the detected polyhedron; determining the visible through-line between the through-body . For interpenetrating polyhedra, it is necessary to calculate the through points to form intersecting edges, and then check the visibility of the intersecting edges one by one, and eliminate the hidden parts. Finally, the elimination of the hidden line of the 3D model A is realized, and then the hidden lines of the other 3D models are sequentially eliminated as described above.

In the three-dimensional model data cylinder method disclosed in the embodiment, the specific cylinder method is to analyze and process the three-dimensional model by using preset view control parameters in the original environment of the three-dimensional model, and finally obtain the data after the cylinder. The embodiment of the present invention simultaneously discloses another image space-based blanking algorithm for implementing a method for analyzing three-dimensional model data according to the view control parameter, and acquiring a three-dimensional model data visible in the view window, and the specific process thereof is as follows: As shown in Figure 5, it includes:

Step S51: Convert the original coordinate of the three-dimensional model data to the view coordinate of the view window according to the preset view control parameter, and the view window uses the data structure according to the preset view. Control parameters are represented;

In this embodiment, the pixel of the view window is represented by a raster data structure according to the view control parameter, where the pixel is a uniform mesh unit divided into a view window plane, and the pixel is a basic information storage unit in the raster data. The coordinate position of the pixel is determined according to the corresponding row number and column number of the pixel in the view window; setting an initial value of the raster data for indicating the serial number of the three-dimensional model data corresponding to the pixel is 0, The initial value of the raster data representing the pixel depth is the value farthest from the viewpoint. According to different systems, if the pixel depth value is smaller, the closer to the viewpoint, the maximum value of the raster data representing the pixel depth is maximized. Value, if the pixel depth value is closer to the viewpoint, the initial value of the raster data representing the pixel depth is given a minimum value.

Each pixel can be represented by the following data structure:

Struct viewPixl

{ Long ModelDatalndex;

Double z Value;

}

ModelDatalndex is used to represent the serial number (or identification number) of the 3D model data, similar to the frame buffer, such as the irregular triangulation (TIN) 3D model, ModelDatalndex is expressed as the serial number of the triangle; zValue is the depth of the pixel (ie z coordinate) ), similar to depth caching.

Step S52, blanking analysis of the coordinate transformed 3D model data;

The image space-based blanking algorithm, such as the Z-buffer algorithm, is used to perform blanking analysis on the coordinate-transformed three-dimensional model data.

Step S53: Perform, according to the result of the blanking analysis, the three-dimensional model data before the coordinate transformation of the cylinder;

Step S54: Acquire the three-dimensional model data after the cylinder as the three-dimensional model data visible in the view window.

Further, before the three-dimensional model data after the coordinate transformation is analyzed by blanking, the three-dimensional model data after the coordinate transformation may be subjected to degradation analysis as needed. For example, the degradation analysis of a polygon, that is, if the 3D model data cannot form a valid polygon in the "model" view window coordinate system, the polygon is rounded off, and if the vertices constituting the polygon are not used by other visible polygons, The vertices are also gone.

For example: Triangulation 3D model, when displaying from the original coordinate system to the "model" view window coordinate system, the three coordinate points of the triangle mesh in the "model" view window coordinate system may be the same, or three The coordinate points on the same line can no longer form a triangle, and the triangle mesh data can be directly discarded.

Through degradation analysis, it is possible to first filter out some data that cannot form a three-dimensional model, further reducing the amount of data for performing blanking analysis, and improving the processing efficiency of the entire cylinder process.

In the blanking analysis, the Z-buffer blanking method is the most commonly used kind of blanking analysis method. It replaces the far object with the near object at the pixel level, which has nothing to do with the order of appearance of the form on the screen. In terms of triangulation, the three-dimensional model data structure is easy to be drawn by all graphics hardware devices. Here, in the embodiment of the present invention, a three-dimensional model of a triangulation network is used as a cylinder object, and a process of performing a three-dimensional model of a triangulation network by using a Z-buffer blanking analysis method is described. The flow is shown in FIG. 6, and includes: Step S61: determining a three-dimensional model of the triangulation to be analyzed from the three-dimensional model of the tribe to be analyzed; selecting a three-dimensional model TMi of the triangulation, wherein i is a serial number of the three-dimensional model of the triangulation, greater than 0, and i is less than or equal to n, n For the number of three-dimensional models to be analyzed, the number of triangles of TMi is m, and the total number Td of processed triangles corresponding to the three-dimensional model TMi is recorded, namely: TCi=TC; then the TC value is increased by m, ie TC=TC +m;

Step S62: Select a current triangle to be analyzed from the triangles that constitute the selected three-dimensional model of the triangulation to be analyzed, and determine the identification number, the three vertices, and the original coordinates of each vertex;

Suppose that a triangle j consisting of TMi is taken out, j is the sequence number of the triangle, j is greater than 0, and j is less than or equal to m. The three vertices of Tj are P _h , P _z , P _k , where h, z, k are More than 0, both are less than or equal to _w , where w is the number of TMi vertices, and the sequence number j of η is added to TQ as the three-dimensional model data Τ" identification number ID, ie ID=j+TCi;

Step S63, transforming the original coordinates of the three vertices according to the view control parameter to obtain view coordinates of the view window;

P _h , P _z , P _{k are} transformed into coordinate points P _h , P _z ', P _{k in the} view window coordinate system, where each coordinate point of Ph, P _z ', Pk contains a depth value, that is, a z coordinate.

Step S64, determining whether the coordinates of the three vertices after the transformation of coordinates can form an effective triangle, and if so, executing step S65, and if not, executing step S614;

The purpose of this step is to perform degradation analysis on the 3D model data. When the three coordinate vertices cannot form a valid triangle, the triangle corresponding to the coordinates of the three vertices can be directly discarded, and no processing is performed to improve the processing efficiency.

This embodiment does not limit the necessity to include the degradation analysis process.

Step S65: Obtain a current pixel to be analyzed on a triangular surface of the current triangle to be analyzed; in this step, a pixel point P _p ' on a triangular patch formed by all Tjs may be sequentially obtained by a “scan line filling algorithm”.

Step S66: Calculate a depth value corresponding to the current pixel to be analyzed according to the coordinates of the three vertices after the transformation of the coordinate;

That is, the depth value z corresponding to Ρ _ρ ' is calculated from the depth values of P _h , P _z ', and P _k .

Step S67: The triangle sequence number and the pixel depth value in the raster data corresponding to the current pixel to be analyzed are read, and it is determined whether the read triangle number is 0. If yes, step S610 is performed. If not, proceed to step S68;

That is, the values of the data ModelDatalndex and zValue of the pixel of Ρ _ρ ' are read, and then it is judged whether ModelDatalndex is equal to 0 or greater than 0.

Step S68, respectively obtaining the depth value in the raster data corresponding to the currently read pixel to be analyzed and the first distance calculated by the viewpoint, and the current calculated according to the three vertex coordinates after the transformation coordinate a depth value corresponding to the pixel to be analyzed and a second distance calculated by the viewpoint;

Step S69, determining whether the first distance is greater than the second distance, and if yes, executing step S610; if not, executing step S611;

In step S610, the triangle number in the raster data corresponding to the current pixel to be analyzed is replaced by the identifier of the current triangle to be analyzed, and the read current value to be analyzed is replaced by the calculated depth value of the pixel. The depth value in the raster data corresponding to the pixel, step S612;

Coming ID value assigned to the raster data corresponding to pixels P _p in ModelDatalndex will zValue value z assigned to the raster pixels Pp 'of corresponding;

Step S611, the triangle sequence number and the pixel depth value in the raster data corresponding to the pixel point are retained, and step S612 is performed;

Step S612, determining whether there is an unanalyzed pixel point on the triangular patch formed by the current triangle to be analyzed, and if yes, executing step S613; if not, executing step S614;

Step S613, obtaining the next unanalyzed pixel on the triangular slice formed by the current triangle to be analyzed as the current pixel to be analyzed, and performing step S66; Step S614, determining the selected three-dimensional model of the current triang to be analyzed Whether there is an unanalyzed triangle in the triangle, if yes, step S615 is performed, if no, step S616 is performed; step S615, determining that the next triangle to be analyzed is the current triangle to be analyzed, and returning to the execution step

S62;

Step S616, determining whether there is an unanalyzed three-dimensional model of the triangulation in the three-dimensional model of the tribe to be analyzed, and if yes, executing step S617; if not, executing step S618;

Step S617, determining that the three-dimensional model of the next triangle to be analyzed is the three-dimensional model of the tribe to be analyzed, and returning to step S61;

Step S618, sequentially acquiring the triangle number corresponding to all the pixel points, and setting the triangle larger than 0. The sequence number is saved to the preset array.

Through the above steps, the serial numbers of all the visible triangles in the three-dimensional model of the triangulation to be analyzed are stored in a preset array, as a basis for purifying the three-dimensional model data of the triangulation network.

Of course, before the start of the blanking analysis process, in order to improve the efficiency of the blanking analysis and reduce the processing amount of data in the blanking analysis process, the following steps may be included to preprocess the original triangulated three-dimensional model, and the preprocessing is performed. After the 3D model data, as the 3D model data of the triangulation to be analyzed, the specific process is shown in Figure 7, including:

Step S71: Convert original coordinates of the minimum bounding box of the three-dimensional model to be processed into view coordinates in the view window coordinate system according to the view control parameter;

The bounding box in this embodiment is a cube or a two-dimensional rectangular shape that accommodates a three-dimensional model of a triangulation.

Step S72: Calculate an outer bounding rectangle of the minimum bounding box of the three-dimensional model in the view window coordinate system and a Z coordinate closest to the distance viewpoint;

Step S73: Sort the three-dimensional models to be processed according to the distance viewpoint from near to far.

Then, in the process of blanking analysis, the three-dimensional model data is sequentially taken from the near and far distances according to the distance viewpoint, and it is determined whether the Z coordinate of the three-dimensional model closest to the viewpoint is larger than the minimum bounding box of the three-dimensional model in the view window. The depth value of all corresponding pixels and the distance calculated by the viewpoint, if yes, the three-dimensional model is discarded, and the blanking analysis is not participated. If not, the three-dimensional model is subjected to blanking analysis for the current three-dimensional model to be processed.

When the pixel values in the view window corresponding to the view control parameter are not all 0, that is, when the 3D model data is displayed in the currently displayed view window, the above-mentioned steps are used to block the 3D model data already existing in the view window. The 3D model is rounded off, and there is no need to participate in the blanking analysis, which improves the processing efficiency of the data to a certain extent.

After the blanking analysis is performed on the three-dimensional model data of the triangulation, according to the result of the blanking analysis, the process of the three-dimensional model data is shown in FIG. 8, which includes:

Step S81, selecting a three-dimensional model of the triangulation to be analyzed from the three-dimensional model of the tribe to be analyzed; Step S82: Select a current triangle to be analyzed from the triangles that constitute the selected three-dimensional model of the tribe to be analyzed, and determine the identification number thereof;

The method of determining the identification number is the same as the method of step S62.

Step S83, determining whether the identification number exists in the preset array, if yes, executing step S84, if not, executing step S85;

Step S84, retaining the triangle, performing step S86;

Step S85, rounding off the triangle, performing step S86;

In step S86, it is determined whether there is an unanalyzed triangle in the triangle constituting the three-dimensional model of the tribe to be analyzed, if yes, step S87 is performed, if not, step S88 is performed; step S87, determining the next triangle to be analyzed Return to the execution step for the current triangle to be analyzed

S82;

Step S88, determining whether the triangle of the current three-dimensional model of the triangulation to be analyzed is all rounded off, if yes, executing step S89, and if not, executing step S810;

Step S89, rounding off the current three-dimensional model of the triangulation to be analyzed, performing step S811, step S810, determining the retained triangle and the corresponding three-dimensional model data as the data of the current three-dimensional model cylinder of the tribe to be analyzed, and performing steps S811 ;

Step S811, determining whether there is an unanalyzed triangulation three-dimensional model in the three-dimensional model of the tribe to be analyzed, and if yes, executing step S812; if not, ending;

Step S812: Determine that the three-dimensional model of the next to-be-analyzed triangulation is the three-dimensional model of the tribe to be analyzed, and return to step S81.

After the above steps, the three-dimensional model data of the triangulation after the cylinder is obtained.

If the above-mentioned acquisition blanking analysis process records the total number of triangles TQ of the previously processed three-dimensional model at the beginning of processing each three-dimensional model TMi, the three-dimensional model may be taken out of order, as long as the TMi is taken, The TQ is simultaneously taken out to calculate the identification number ID; the scan line filling algorithm is a prior art, and details are not described herein again.

In the 3D model for blanking analysis, the attributes of the 3D model should be considered, such as the transparency of the 3D model, to avoid the transparent part of the 3D model to participate in the blanking analysis; in the Z-buffer of the blanking algorithm, the object space method can be combined. Such as back culling, to remove some apparently invisible surface, thereby improving the efficiency of the blanking algorithm. In the above processing, the visible three-dimensional model data includes: visible three-dimensional model geometric data and visible three-dimensional model texture data. The blanking analysis of the 3D model is mainly based on the geometric data of the 3D model. Since the geometric data of the 3D model is visible, the corresponding texture data is also visible; if the geometric data of the 3D model is not visible, the corresponding texture data is not visible, then The specific process of determining the data of the three-dimensional model data visible in the view window as the post-cylinder data is as shown in FIG. 9, and includes:

Step S91, determining that the three-dimensional model geometric data visible in the view window is the data of the chemical cylinder;

Step S92: Determine visible three-dimensional model texture data corresponding to the visible three-dimensional model geometric data as post-booster data.

Through the above steps, the visible three-dimensional model geometric data is first determined as the post-booster data, and then the visible three-dimensional model texture data corresponding to the visible three-dimensional model geometric data is determined as the post-booster data.

Further, after the visible three-dimensional model texture data corresponding to the visible three-dimensional model geometric data is determined, further processing may be performed, including:

Converting original coordinates of the visible three-dimensional model geometric data to view coordinates of the view window according to the view control parameter;

Obtaining, according to the view coordinates, a display range of the visible three-dimensional model geometric data when the view window is displayed;

When the preset display rule is: when the range of the three-dimensional model texture data displayed in the view window is less than a preset value, and the texture data corresponding to the visible three-dimensional model geometric data is not displayed, according to the visible three-dimensional Determining, by the display range of the model geometric data, when the view window is displayed, whether the range of the three-dimensional model texture data displayed in the view window is smaller than the preset value, and if not, discarding the visible three-dimensional If the texture data corresponding to the model geometric data is not smaller, the texture data corresponding to the geometric data of the visible three-dimensional model is retained;

And when the display range of the visible three-dimensional model geometric data when the view window is displayed is smaller than the original size of the texture data corresponding to the visible three-dimensional model geometric data, the texture data is used according to the texture data. The display range when the view window is displayed is compressed. The compressed texture data is finally determined to be texture data corresponding to the visible three-dimensional model geometric data.

The preset display rules in this embodiment may be set according to actual conditions, for example, The number of pixels displayed for the texture data in the view window corresponding to the current view parameter is five, and if the number of pixels required for the three-dimensional model texture data to be displayed in the view window is less than five, the texture is The data does not need to be displayed. In this embodiment, the texture data corresponding to the visible three-dimensional model geometric data is preprocessed by a preset display rule, and the texture data that does not need to be displayed is first removed, thereby reducing the data transmission amount.

The specific compression process in this embodiment is:

When the visible texture data is displayed, if the size of the visible texture displayed in the view window (which can be represented by the width of the texture multiplied by the height of the texture) is smaller than the size of the original texture, it means that the texture has multiple data. Draw on the same pixel of the view window. Therefore, the visible texture data corresponding to the pixel can be normalized, and only one data that is visible when displayed in the view window is retained, and the rest is removed, that is, determined and determined. Visible to the visible pixels of the visible three-dimensional model geometric data corresponding to the three-dimensional model texture data, the plurality of data in the visible three-dimensional model texture data corresponding to the pixel are purified, and only three-dimensional is retained. Data visible in the model texture data when displayed in the view window. Further, the method further includes: synthesizing the visible three-dimensional model texture data into a texture according to the view control parameter and the three-dimensional model geometric data; and recalculating the texture coordinates of the visible three-dimensional model. The calculation method of the texture coordinates of the vertices in the geometric data of the 3D model is:

Converting original coordinates of the vertices in the three-dimensional model geometric data into view coordinates under the view window represented by the view control parameter according to the view control parameter;

When the view coordinate is within the view window represented by the view control parameter, the view coordinate is the texture coordinate corresponding to the visible three-dimensional model geometric data;

When the view coordinates are outside the range of the view window represented by the view control parameter, the geometric data of the three-dimensional model is cropped by using the outer-out rectangle of the view window represented by the view control parameter, and the cropped three-dimensional image is The vertex coordinates in the geometric data of the model are determined as the texture coordinates corresponding to the visible 3D model geometric data.

If the texture coordinates are to be normalized (for example, the texture coordinate of the OpenGL 3D engine is required to be normalized between 0 and 1), the method further includes: normalizing the texture coordinates corresponding to the visible 3D model geometric data. Processing, dividing the abscissa of the texture coordinate by the view in the view control parameter The width of the window, the ordinate divided by the height of the view window in the view control parameter. This ensures that the amount of texture data of the three-dimensional model after the cylinder is independent of the size of the original texture data, and is only related to the resolution of the view window.

The process of synthesizing the visible three-dimensional model texture data into a synthetic texture according to the view control parameter and the three-dimensional model geometric data includes:

And drawing the visible three-dimensional model data according to the view control parameter, and generating an image of the same size of the outer envelope corresponding to the view control parameter;

The image is determined to be a composite texture of the visible three-dimensional model texture data.

In the three-dimensional model data processing method disclosed in the embodiment of the present invention, the three-dimensional model is not limited to a three-dimensional model of a triangulation network, and may be any other three-dimensional model, and the blanking algorithm adopted by the embodiment is not limited to the Roberts algorithm or Z- The buffer algorithm can also use other types of blanking algorithms, or an algorithm that combines object space and image space blanking algorithms, or other algorithms, any three-dimensional model and any data that can be analyzed based on view control parameters. An algorithm that can analyze the three-dimensional model data visible in the view window corresponding to the view control parameter is also suitable for the present invention.

The invention also discloses a three-dimensional model data cylinder device, the structure of which is shown in FIG. 10, which includes:

The parameter setting module 101 is configured to set a view control parameter corresponding to the view window, where the view control parameter includes at least: an outsourcing rectangle, a view point parameter, and a projection parameter of the view window;

The analysis obtaining module 102 is configured to analyze the three-dimensional model data according to the view control parameter, and obtain the three-dimensional model data visible in the view window;

The determining module 103 is configured to determine the three-dimensional model data that is visible in the view window as post-initial data.

Specifically, for different types of blanking algorithms,

When the blanking algorithm is the image space blanking algorithm, the analysis obtaining module includes: a coordinate transformation unit, configured to convert the original coordinate of the three-dimensional model data according to the preset view control parameter View coordinates of the view window, the view window being expressed by the data structure according to the preset view control parameter;

a blanking analysis unit, configured to blank-analyze the coordinate-transformed three-dimensional model data; a chemical tube unit, configured to perform a three-dimensional mode before the coordinate transformation according to the result of the blanking analysis Type data, the three-dimensional model data after the cylinder is acquired as the three-dimensional model data visible in the view window.

The execution process of the three-dimensional model data-cylinder device disclosed in this embodiment is a flow of the method embodiment corresponding to the embodiment of the present invention, which is a preferred device embodiment. For the specific implementation process, refer to the foregoing method embodiment. This will not be repeated here.

The three-dimensional model data cylinder device disclosed in the embodiment reduces the data of the three-dimensional model data that is invisible under the view window corresponding to the view control parameter by analyzing the three-dimensional model data by using the preset view control parameter. The amount of data in the transmission process increases the data transmission speed.

The three-dimensional model data cartridge device disclosed in the present invention may be disposed in a computer or in a mobile phone or other device. It can be set on the server side, before the data requested by the client is sent, the 3D model data is first processed, or it can be set on the client, and the data is sent before being sent to the actual view window. The processing is performed, or both at the server and the client, and depending on the actual situation, which party or both parties are jointly processed. The invention also discloses a three-dimensional model data progressive transmission method based on the above three-dimensional model data cylinder method. In the case of the view view, the size of the view window used to display the 3D model is determined, because the total number of pixels that can be displayed by the view window is fixed, so no matter how massive the 3D model data is, the 3D can be displayed on the view window. The maximum number of model data is fixed, that is, the visible 3D model data required to fill all the pixels of the view window is fixed, so when the client requests the 3D model data for display to the server, the server only needs to The 3D model data (incremental data) that is visible on the client display and not available to the client is transmitted to the client.

According to the above principle, the incremental data transmission method of the three-dimensional model data disclosed by the present invention uses the view control parameter of the incremental data requesting end to obtain the incremental data, thereby ensuring the lossless display of the data, reducing the data transmission amount and reducing the complexity of the algorithm. The specific implementation scheme is as follows:

First, the method is described in detail from the perspective of the sender of the incremental data request. The process of the progressive transmission method of the three-dimensional model data disclosed in this embodiment is as shown in FIG. 11, and includes:

Step S111: When the incremental data needs to be requested, the requesting end sends an incremental data request, where the incremental data request includes at least a view control parameter, and the view control parameter includes at least: a current view control parameter; When the requesting end determines that the incremental data needs to be requested, the requesting receiving end sends an incremental data request, where the request includes at least the current view control parameter of the requesting sending end.

The current view control parameter is a view control parameter corresponding to a view window of the current sending end for displaying the incremental data.

The view control parameter includes: an outsourcing rectangle of the view window, a viewpoint parameter and a projection parameter; the viewpoint parameter includes a position of the viewpoint in the world coordinate system, a target position observed by the viewpoint, and a vector of the virtual camera upward; the projection parameter Including: orthogonal projection and perspective projection; or the view matrix and projection matrix obtained by the above parameters.

If the request contains other content in addition to the view control parameter, it is also necessary to obtain incremental data according to other contents included in the request.

At this time, if the requesting sender does not cache the 3D model data of the pre-bubble, the view control parameter at this time only includes: the current view control parameter of the requesting sender. The request receiving end obtains the incremental data according to the above parameters.

When the request sending end caches the priorized three-dimensional model data, and the request receiving end does not record the identification number of the priorized three-dimensional model data buffered by the requesting sending end, the incremental data request further includes The identification number of the three-dimensional model data after the pre-synthesis tube, and/or the view control parameter further includes: a prior view control parameter, requesting the receiving end to identify the identification number of the three-dimensional model data after the pre-synchronization cylinder sent by the requesting end / or the prior view control parameters, as well as the current view control parameters, to obtain incremental data.

The previous view control parameter is a current view control parameter corresponding to the last time the request sender sends the incremental data request for the incremental data request, that is, the request sender sends the last request increment. When the data is displayed, the view control parameters corresponding to the view window of the three-dimensional model data are displayed.

When the requesting sender needs to send the identification number of the three-dimensional model data to the request receiving end, the requesting sending end may analyze the three-dimensional model data buffered by the requesting sending end through the chemical cylinder according to the current view control parameter of the requesting sending end. Obtaining an identification number of the visible three-dimensional model data that is already present in the view window corresponding to the current view control parameter, and sending the identification number of the three-dimensional model data as the priorizing cylinder to the request receiving end, thereby reducing the transmitted data. the amount.

If the requesting sender caches the prior art three-dimensional model data and also records at the request receiving end The request number sent by the request sender is buffered, and the sent request includes only the current view control parameter of the request sender, and the request receiver sends according to the current view control parameter and the request recorded by itself. The identification number of the three-dimensional model data of the prior stream is obtained by the end buffer, and the incremental data is obtained.

If the requesting sender caches all the three-dimensional model data transmitted from the request receiving end and does not record the identification number of all the three-dimensional model data buffered by the requesting sender at the request receiving end, the transmitted request includes the current requesting sender. In addition to the view control parameter, the identifier of the three-dimensional model data visible in the current view window of the request sending end in the three-dimensional model data buffered by the requesting end is requested, and the request receiving end controls the parameter according to the current view and the request sending end. In the cached 3D model data, the identification number of the 3D model data currently visible in the view window is obtained as incremental data.

The identification number of the three-dimensional model data visible in the current view window of the request sending end in the three-dimensional model data cached by the requesting end is analyzed by analyzing the request sending end buffer according to the current view control parameter 3D model data to get.

If the requesting sender caches all the three-dimensional model data transmitted from the request receiving end and records the identification number of all the three-dimensional model data buffered by the requesting sender at the request receiving end, the sent request only includes the current requesting sender. The view control parameter, the request receiving end obtains the incremental data according to the current view control parameter and the identification number of the three-dimensional model data cached by the requesting end of the request. Step S112: Receive incremental data sent by the request receiving end, where the incremental data is that the request sending end analyzes the three-dimensional model data according to the view control parameter, and obtains the visible view window corresponding to the current view control parameter. The three-dimensional model data is obtained after analysis based on the view control parameters.

After receiving the incremental data request, the request receiving end performs the three-dimensional model data according to the three-dimensional model dataization cylinder method disclosed in the present invention, and obtains the incremental data from the data after the chemical cylinder, and sends the incremental data to the request transmitting end. .

Further, if all three-dimensional model data transmitted from the request receiving end is cached at the requesting end, the incremental data is inserted into the three-dimensional model data buffered by the requesting sending end to implement data. Rebuilding; if the requesting sender only caches the previous 3D model data transmitted from the request receiving end, the cached previous 3D model data is released, and the current incremental data is cached, if If the view control parameter of the requesting sender includes the previous view control parameter, the previous view control parameter is replaced with the current view control parameter.

In the progressive transmission method of the three-dimensional model data disclosed in the embodiment, when the requesting sender sends the incremental data request, the request carries the view control parameter of the view window that needs to be displayed, so that the request receiving end can view the view according to the view. Control parameters, find incremental data that matches the current view window, and transmit, ensuring that the found incremental data can be displayed without loss, reducing the amount of data transmission and improving data transmission efficiency.

Another flow of the three-dimensional model data progressive transmission method disclosed in the embodiment of the present invention is shown in FIG. 12, and includes:

Step S121: Receive an incremental data request sent by the requesting end, where the incremental data request includes at least a view control parameter, where the view control parameter includes at least: a current view control parameter; and the progressive transmission of the three-dimensional model data disclosed in this embodiment The method is applicable to the requesting end. The content contained in the received data delta request corresponds to the content contained in the request described in the embodiment shown in FIG. The three-dimensional model data identification number may also be included in the cached prior stream, and/or the view parameter further includes: the prior view control parameter is obtained according to the first-dimensional post-dimensional three-dimensional model data identification number or the prior view control parameter. The 3D model data after the cartridge is used for subsequent incremental data analysis.

Step S122: Analyze the three-dimensional model data according to the view control parameter, and obtain the three-dimensional model data that is visible in the view window corresponding to the view control parameter;

Step S123, determining that the three-dimensional model data visible in the view window is the data of the cylinder; the specific implementation process of the foregoing steps may refer to the method of the cylinder disclosed in the embodiment of the three-dimensional model data cylinder of the present invention, and the specific content is not Let me repeat.

Step S124: Analyze the data after the cylinder, and determine that the three-dimensional model data that meets the incremental condition is incremental data;

Step S125: Send the incremental data to the request sending end.

In the progressive transmission method of the three-dimensional model data disclosed in the embodiment, the request receiving end acquires the incremental data according to the view control parameter of the requesting sender, so that the request receiving end only uses the view window defined by the current view control parameter at the requesting sending end. Data visible in the increment condition and sent to Request the sender. In the method, the analysis process of the three-dimensional model data is performed according to the view control parameter in the incremental data request, that is, based on the current actual display view window of the requesting sender, thereby realizing that the obtained incremental data can be at the request sending end. Performing lossless display and transmitting only incremental data greatly reduces the amount of data transmission and improves data transmission efficiency.

If the request contains other content in addition to the view control parameter, it is also necessary to obtain incremental data according to other contents included in the request. Based on the above situation, the flow of the further progressive transfer method of the three-dimensional model data disclosed in the present invention is as shown in FIG. 13:

Step S131: Receive an incremental data request sent by the requesting sender, where the incremental data request includes: a three-dimensional model data identification number and a view control parameter after the pre-forwarding, the view control parameter at least: the current view control parameter ;

When the request sending end caches the three-dimensional model data transmitted from the request accepting end, and the request receiving end does not record the identification number of the priorized three-dimensional model data buffered by the requesting sending end, the incremental data The request also includes: The identification number of the 3D model data after the priorization cylinder.

Step S132: Analyze the three-dimensional model data according to the current view control parameter, and obtain three-dimensional model data that is visible in a view window corresponding to the current view control parameter;

Step S133: Determine that the three-dimensional model data that is visible in the view window corresponding to the current view control parameter is the current data of the currentization tube;

Step S134: Rounding off the same part of the three-dimensional model data corresponding to the identification number of the three-dimensional model data after the priorizing cylinder in the data of the currentization cylinder and the incremental data request;

Step S135: Determine remaining 3D model data as incremental data;

Step S136: Send the incremental data to the request sending end.

The method disclosed in this embodiment is particularly applicable to the case where the requesting sender only caches the three-dimensional model data displayed in the view window in the previous three-dimensional scene of the current three-dimensional scene. Since the request contains the identification number of the three-dimensional model data after the priorizing cylinder, it is necessary to obtain the data after the priorizing cylinder according to the identification number of the three-dimensional model data after the priorizing cylinder, and then the data and the current cylinder result Compare to get incremental data. Similarly, the flow of the third-dimensional model data progressive transmission method disclosed in the present invention is as shown in FIG. 14, and includes: Step S141: Receive an incremental data request sent by the requesting end, where the incremental data request includes: at least a view control parameter, where the view control parameter includes: a current view control parameter and a prior view control parameter;

The view control parameter further includes: when the request sending end caches the prior art three-dimensional model data and does not record the identification number of the pre-formed three-dimensional model data of the request sending end buffer at the request receiving end, the view control parameter further includes: The previous view controls the parameters.

The process of analyzing the three-dimensional model data according to the view control parameter, and acquiring the three-dimensional model data visible in the view window corresponding to the view control parameter is as shown in steps S 142 and S143, that is, according to the prior view control parameter and the current view, respectively. The control parameters are used to normalize the 3D model data to obtain visible 3D model data.

Step S142: Analyze the three-dimensional model data according to the current view control parameter, and obtain three-dimensional model data that is visible in a view window corresponding to the current view control parameter;

Step S143: Analyze the three-dimensional model data according to the previous view control parameter, and obtain three-dimensional model data that is visible in a view window corresponding to the previous view control parameter;

The process of determining the three-dimensional model data visible in the view window as the post-synthesis data is as shown in steps S144 and S145.

Step S144: Determine that the three-dimensional model data that is visible in the view window corresponding to the current view control parameter is the data of the currentization tube;

Step S145: Determine that the three-dimensional model data visible in the view window corresponding to the previous view control parameter is the data after the priorization.

Step S146, determining that the three-dimensional model data in the data of the currentization cylinder and not in the data of the priorization cylinder is incremental data;

Step S147: Send the incremental data to the request sending end.

The method for progressively transmitting the three-dimensional model data disclosed in this embodiment is also applicable to the case where only three-dimensional model data displayed in the view window in the previous three-dimensional scene of the current three-dimensional scene is cached on the request sending end. Since the previous view control parameter is included in the request, the data after the priorizer is obtained according to the parameter, and the data is compared with the current tube result to obtain the incremental data. Moreover, since the data amount of the previous view control parameter in the transmission process is smaller than the data amount of the three-dimensional model data identification number buffered after the priorization cylinder, the data transmission amount is reduced to some extent, and the number is increased. According to transmission efficiency.

Further, the flow of the third-dimensional model data progressive transmission method disclosed in the embodiment of the present invention is as shown in FIG. 15, and includes:

Step S151: Receive an incremental data request sent by the requesting end, where the incremental data request includes: at least a view control parameter, where the view control parameter includes: a current view control parameter; Step S152, according to the current view control Parameter analyzing the three-dimensional model data, and acquiring three-dimensional model data visible in a view window corresponding to the current view control parameter;

Step S153: Determine that the three-dimensional model data that is visible in the view window corresponding to the current view control parameter is the data of the currentization tube;

Step S154: Rounding off the same data as the data corresponding to the identification number of the three-dimensional model data buffered by the requesting sender stored in the data received by the request receiving end;

Step S155, determining remaining three-dimensional model data as incremental data;

Step S156: Send the incremental data to the request sending end.

In the progressive transmission method of the three-dimensional model data disclosed in this embodiment, the request receiving end records the identification number of the three-dimensional model data buffered by the requesting sender, and therefore, only the current view control parameter needs to be transmitted to the request receiving end.

The three-dimensional model data progressiveization method disclosed in the embodiment of the present invention may be any three-dimensional model dataization cylinder method disclosed in the embodiments of the present invention, which is not limited herein.

The invention also discloses a three-dimensional model data progressive transmission device, the structure of which is shown in FIG. 16, and includes:

The request sending module 161 is configured to: when the incremental data needs to be requested, the requesting sending end sends an incremental data request, where the incremental data request includes at least a view control parameter, and the view control parameter includes at least: a current view control parameter;

The incremental data receiving module 162 is configured to receive the incremental data sent by the requesting receiving end, where the incremental data is used by the requesting sending end to analyze the three-dimensional model data according to the view control parameter, and obtain the corresponding control parameter in the current view. The 3D model data visible in the view window is obtained after analysis based on the view control parameters.

The three-dimensional model data progressive transmission device disclosed in this embodiment can be used as a client.

Further, when the requesting sender caches all the three-dimensional model numbers transmitted from the request receiving end According to the time, the method further includes: an interpolation module, configured to insert the incremental data into the three-dimensional model data buffered by the request sending end to implement data reconstruction.

When the requesting sender only caches the previous three-dimensional model data transmitted from the request receiving end, the method further includes:

a data replacement module, configured to release the cached previous three-dimensional model data, and cache the current incremental data;

When the view control parameter includes the previous view control parameter, the method further includes:

And a parameter replacement module, configured to replace the previous view control parameter with the current view control parameter.

The execution process of the three-dimensional model data progressive transmission device disclosed in this embodiment is a flow corresponding to the method embodiment shown in FIG. 11 disclosed in the foregoing embodiment of the present invention, which is a preferred device embodiment, and the specific execution process can be seen but not It is limited to the foregoing method embodiments, and specific processing procedures are not described herein again.

Correspondingly, the present invention discloses another three-dimensional model data progressive transmission device, and its structure is as shown in FIG. 17, which includes:

The request receiving module 171 is configured to receive an incremental data request sent by the requesting sender, where the incremental data request includes at least a view control parameter, and the view control parameter includes at least: a current view control parameter;

The obtaining module 172 is configured to analyze the three-dimensional model data according to the view control parameter, and obtain three-dimensional model data that is visible in a view window corresponding to the view control parameter;

a determining module 173, configured to determine that the three-dimensional model data visible in the view window is post-initial data;

An analysis module 174, configured to analyze the data after the cylinder, and determine that the three-dimensional model data that meets the incremental condition is incremental data;

The incremental data sending module 175 is configured to send the incremental data to the request sending end.

The three-dimensional model data progressive transmission device disclosed in this embodiment can serve as a server end, and receives the incremental data request sent by the client in the previous embodiment.

The execution process of the three-dimensional model data progressive transmission device disclosed in this embodiment may be a flow corresponding to the method embodiment shown in any one of the figures 12-15 disclosed in the embodiment of the present invention, which is a preferred device embodiment. The specific implementation process can be referred to, but is not limited to the foregoing method embodiments, and the specific processing procedure. I will not repeat them here.

In the 3D model data progressive transmission device disclosed in the embodiment of the present invention, the request receiving end acquires the incremental data according to the view control parameter of the requesting sending end, so that the request receiving end only views the current view control parameter of the requesting sending end. Data visible in the window and meeting the incremental conditions is sent to the requesting sender. In the method, the analysis process of the three-dimensional model data is performed according to the view control parameter in the incremental data request, that is, based on the actual display view window of the requesting sender, so that the obtained incremental data can be performed at the request sending end. Display, only the incremental data is transmitted at the same time, which greatly reduces the amount of data transmission and improves the data transmission efficiency.

The three-dimensional model data cartridge device disclosed in the present invention may be disposed in a computer or in a mobile phone or other device.

The various embodiments in the present specification are described in a progressive manner, and each embodiment focuses on differences from other embodiments, and the same similar parts between the various embodiments may be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the comparison is described, and the relevant part can be referred to the method part.

A person skilled in the art will further appreciate that the elements and algorithm steps of the various examples described in connection with the embodiments disclosed herein can be implemented in electronic hardware, computer software or a combination of both, in order to clearly illustrate the hardware and software. Interchangeability, the composition and steps of the various examples have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods for implementing the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present invention.

The steps of a method or algorithm described in connection with the embodiments disclosed herein can be implemented directly in hardware, a software module executed by a processor, or a combination of both. Software modules can be placed in random access memory (RAM;), internal memory, read only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or technical field Any other form of storage medium known.

The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be practiced without departing from the spirit or scope of the invention. Implemented in other embodiments. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but the scope of the inventions

Claims

Rights request

A method for digitizing a three-dimensional model, characterized in that it comprises:

Setting a view control parameter corresponding to the view window;

2. The method according to claim 1, wherein the view control parameter comprises: an outsourcing rectangle of a view window, a viewpoint parameter and a projection parameter; the viewpoint parameter includes a position of the viewpoint in the world coordinate system, and a viewpoint Observed target position and vector of virtual camera up; the projection parameters include: orthogonal projection and perspective projection;

Or include: an outer rectangle of the current view window, a view matrix and a projection matrix obtained from viewpoint parameters and projection parameters.

The method according to claim 2, wherein the process of analyzing the three-dimensional model data according to the view control parameter to obtain the three-dimensional model data visible in the view window comprises:

And analyzing the three-dimensional model data according to the view control parameter, and discarding the three-dimensional model data of the three-dimensional model data that is occluded by other three-dimensional model data in the three-dimensional model;

And analyzing the three-dimensional model data according to the view control parameter, and discarding the three-dimensional model data of the three-dimensional model data that is occluded by the three-dimensional model data of the other three-dimensional model;

According to the view control parameter, the three-dimensional model data visible in the view window in the remaining three-dimensional model data is determined as post-synthesis data.

The method according to claim 3, wherein the analyzing the three-dimensional model data according to the view control parameter, and omitting the three-dimensional model data of the three-dimensional model data in the three-dimensional model data of the three-dimensional model The process of going to include:

Determining a certain surface of the three-dimensional model as a current to-be-processed surface, and determining that any point on the current to-be-processed surface is a test point;

Calculating an angle between a line of sight vector obtained by the test point according to the viewpoint parameter and an outer polygon plane normal vector of the test point;

When the cosine value of the included angle is greater than or equal to 0, determining that the current to-be-processed surface is visible, When the cosine value of the angle is less than 0, it is determined that the current to-be-processed surface is invisible, and the invisible three-dimensional model data corresponding to the current to-be-processed surface is discarded;

When there is an unprocessed surface in the three-dimensional model, it is determined that the next side is the current to-be-processed surface, and any point on the current to-be-processed surface is a test point, and the line of sight vector obtained by calculating the test point according to the viewpoint parameter is returned. The step of an angle with the outer polygon plane normal vector of the test point.

The method according to claim 3, wherein the process of analyzing the three-dimensional model data according to the view control parameter and discarding the three-dimensional model data occluded by the three-dimensional model data of the other three-dimensional model data includes:

Sorting the three-dimensional model data in order of distance and near distance;

The three-dimensional model data is sequentially analyzed in order of near and far, and the occluded three-dimensional model data after the analyzed three-dimensional model data is discarded.

The method according to claim 1, wherein the process of analyzing the three-dimensional model data according to the view control parameter to obtain the three-dimensional model data visible in the view window comprises:

Performing, according to the preset view control parameter, the original coordinate of the three-dimensional model data to obtain view coordinates of the view window, where the view window is performed according to the preset view control parameter by using a data structure. Express

Blanking analysis of the coordinate transformed 3D model data;

And calculating, according to the result of the blanking analysis, the three-dimensional model data before the coordinate transformation; and acquiring the three-dimensional model data after the cylinder as the three-dimensional model data visible in the view window.

The method according to claim 6, wherein the process of the view window being represented by the data structure according to the view control parameter comprises:

Depending on the view control parameter, the pixel of the view window is represented by a raster data structure, the pixel is a uniform mesh unit divided into a view window plane, and the pixel is a basic information storage unit in the raster data, and the coordinates of the pixel Position is determined according to a corresponding row number and column number of the pixel in the view window;

The initial value of the raster data for setting the sequence number of the three-dimensional model data corresponding to the pixel is 0, and the initial value of the raster data for indicating the pixel depth is the value farthest from the viewpoint.

8. The method according to claim 7, wherein when the three-dimensional model data is three When the three-dimensional model data of the corner network is used, the original coordinate of the three-dimensional model data is transformed into the view coordinate of the view window according to the preset view control parameter, and the three-dimensional model after the coordinate transformation is blanked and analyzed. The process of data includes:

Determining the current three-dimensional model of the triangulation to be analyzed from the three-dimensional model of the triangulation to be analyzed;

Selecting a current triangle to be analyzed from the triangles constituting the selected three-dimensional model of the triangulation to be analyzed, determining the identification number, the three vertices, and the original coordinates of each vertex;

And transforming the original coordinates of the three vertices according to the view control parameter to obtain view coordinates of the view window;

According to the triangle formed by the coordinates of the three vertices after the transformation of the coordinates, all the pixel points on the triangular surface of the triangle are sequentially obtained;

Determining a pixel value to be analyzed, and calculating a depth value corresponding to the current pixel to be analyzed according to the coordinates of the three vertices after the transformation coordinate;

Reading a triangle sequence number and a pixel depth value in the raster data corresponding to the current pixel to be analyzed, and when the triangle sequence number is 0, replacing the current pixel to be analyzed with the identifier of the current triangle to be analyzed. a triangle number in the raster data corresponding to the point, and replacing the depth value in the raster data corresponding to the current pixel to be analyzed by using the calculated depth value of the pixel, when the triangle serial number is not 0, the depth value in the raster data corresponding to the currently read pixel to be analyzed and the first distance calculated by the viewpoint, and the calculated according to the coordinates of the three vertices after the transformation coordinate are respectively obtained. The depth value corresponding to the pixel to be analyzed and the second distance calculated by the viewpoint, determining whether the first distance is greater than the second distance, and if so, replacing the current to-be-analyzed with the identification number of the current triangle to be analyzed a triangle number in the raster data corresponding to the pixel, and replacing the depth in the raster data corresponding to the read pixel by using the calculated depth value of the pixel If not, retaining the triangle number and the pixel depth value in the raster data corresponding to the pixel, determining whether there is an unanalyzed pixel on the triangular surface of the current triangle to be analyzed, and if so, acquiring the next The unanalyzed pixel is the current pixel to be analyzed, and the step of performing the depth value corresponding to the current pixel to be analyzed according to the coordinates of the three vertices after the transformation of the coordinate is performed, and if not, determining the selected Whether there is an unanalyzed triangle in the triangle of the three-dimensional model of the triangulation to be analyzed, and if so, determining the next triangle to be analyzed as the current triangle to be analyzed, and returning the identification number, the three vertices, and the original coordinates of each vertex Step, if not present, determining the triangulation to be analyzed Whether there is an unanalyzed three-dimensional model of the triangulation in the three-dimensional model, and if so, determining that the next three-dimensional model of the tribe to be analyzed is the three-dimensional model of the tribe to be analyzed, and returning to perform the three-dimensional three-dimensional analysis of the current to be analyzed The step of selecting a triangle to be analyzed is selected from the triangles of the model. If not, the triangle numbers corresponding to all the pixel points are sequentially acquired, and the triangle numbers greater than 0 are saved to the preset array.

9. The method according to claim 8, wherein the process of refining the three-dimensional model data according to the result of the blanking analysis comprises:

Selecting a three-dimensional model of the triangulation to be analyzed from the three-dimensional model of the triangulation to be analyzed;

Selecting a current triangle to be analyzed from the triangles constituting the selected three-dimensional model of the triangulation to be analyzed, and determining an identification number thereof;

Determining whether the identification number exists in the preset array, if yes, retaining the triangle, if not, rounding off the triangle;

Determining whether there is an unanalyzed triangle in the triangle constituting the three-dimensional model of the current triangle to be analyzed, and if yes, determining that the next triangle to be analyzed is the current triangle to be analyzed, and returning to perform the step of determining the identification number thereof, if not, Determining whether the triangles of the current three-dimensional model of the triangulation to be analyzed are all rounded off, and if so, rounding off the three-dimensional model of the current triangulation to be analyzed, and if not, determining the retained triangles and the corresponding three-dimensional model data as Describe the data of the current three-dimensional model cylinder of the triangulation to be analyzed;

Determining whether there is an unanalyzed triangulation three-dimensional model in the three-dimensional model of the triangulation to be analyzed, and if so, determining that the next three-dimensional model of the triangulation to be analyzed is the current three-dimensional model of the triangulation to be analyzed, and returning to perform the current triangulation to be analyzed from the composition selected The step of selecting the current triangle to be analyzed from the triangle of the 3D model, and if not, ending.

10. The method according to claim 1, wherein the visible three-dimensional model data comprises: visible three-dimensional model geometric data and visible three-dimensional model texture data;

The process of determining the three-dimensional model data visible in the view window as the post-synthesis data includes:

Determining the three-dimensional model geometric data visible in the view window as post-synthesis data;

The visible three-dimensional model texture data corresponding to the visible three-dimensional model geometric data is determined as post-initial data.

The method according to claim 10, wherein the process of determining the visible three-dimensional model texture data corresponding to the visible three-dimensional model geometric data as post-synthesis data comprises: according to the view control parameter, Converting the original coordinate of the visible three-dimensional model geometric data to obtain view coordinates of the view window;

When the preset display rule is: when the range of the three-dimensional model texture data displayed in the view window is smaller than a preset value, when the three-dimensional model texture data is not displayed, according to the visible three-dimensional model geometric data Determining, by the display range when the view window is displayed, whether the range of the three-dimensional model texture data displayed in the view window is smaller than the preset value, and if not, discarding the corresponding geometric data of the visible three-dimensional model The texture data, if not less than, retains the texture data corresponding to the visible three-dimensional model geometric data;

And when the display range of the visible three-dimensional model geometric data when the view window is displayed is smaller than the original size of the texture data corresponding to the visible three-dimensional model geometric data, the texture data is used according to the texture data. The display range when the view window is displayed is compressed.

12. The method according to claim 10, further comprising:

Combining the visible three-dimensional model texture data into a synthetic texture according to the view control parameter and the three-dimensional model geometric data;

The texture coordinates of the visible three-dimensional model data are recalculated.

13. The method according to claim 12, wherein the recalculating the texture coordinates of the visible three-dimensional model comprises:

14. The method according to claim 13, further comprising:

The texture coordinates corresponding to the visible three-dimensional model geometric data are normalized, and the specific processes include:

The abscissa of the texture coordinates is divided by the width of the view window in the view control parameter, and the ordinate is divided by the height of the view window in the view control parameter.

15. The method according to claim 12, wherein the process of synthesizing the visible three-dimensional model texture data into a synthetic texture according to the view control parameter and the three-dimensional model geometric data comprises:

16. A three-dimensional model data cartridge device, comprising:

The device according to claim 16, wherein the analysis obtaining module comprises: a coordinate transformation unit, configured to transform the original coordinate of the three-dimensional model data according to the preset view control parameter View coordinates of the view window, the view window being represented by the data structure according to the preset view control parameter;

a blanking analysis unit, configured to perform blanking analysis on the coordinate transformed 3D model data;

And a chemical tube unit, configured to: according to the result of the blanking analysis, the three-dimensional model data before the coordinate transformation is obtained, and the three-dimensional model data after the chemical cylinder is acquired as the three-dimensional model data visible in the view window.

18. A method for progressive transmission of three-dimensional model data, comprising:

When the incremental data needs to be requested, the requesting sender sends an incremental data request, where the incremental data request includes at least a view control parameter, and the view control parameter includes at least: a current view control parameter; And receiving the incremental data sent by the request receiving end, where the incremental data is used by the request receiving end to analyze the three-dimensional model data according to the view control parameter, and obtain the three-dimensional model data visible in the view window corresponding to the current view control parameter. And obtained according to the analysis of the view control parameters.

The method according to claim 18, wherein when the request sending end caches the priorized three-dimensional model data, the request receiving end does not save the priorizing buffer buffered by the request sending end. When the identification number of the three-dimensional model data, the incremental data request further includes: an identification number of the three-dimensional model data after the priorizing cylinder, and/or the view control parameter further includes: a prior view control parameter.

The method according to claim 18, wherein the current view control parameter comprises: an outer rectangle of a current view window, a viewpoint parameter and a projection parameter; the viewpoint parameter includes a position of the viewpoint in the world coordinate system, The target position observed by the viewpoint and the vector of the virtual camera upward; the projection parameters include: orthogonal projection and perspective projection.

The method according to claim 18, wherein when the requesting end buffer buffers the three-dimensional model data transmitted from the request receiving end, the method further includes:

And inserting the incremental data into the three-dimensional model data buffered by the request sending end to implement data reconstruction;

The cached previous 3D model data is released, and the current incremental data is cached. When the view control parameter includes the prior view control parameter, the method further includes:

The previous view control parameter is replaced with the current view control parameter.

22. A method for progressive transmission of three-dimensional model data, comprising:

Determining that the three-dimensional model data visible in the view window is data after the cylinder;

The data after the cylinder is analyzed, and the three-dimensional model data that meets the incremental condition is determined to be incremental data; and the incremental data is sent to the request sending end.

23. The method according to claim 22, wherein in the view control parameter The method further includes: when the first view control parameter is used, the analyzing the three-dimensional model data according to the view control parameter, and acquiring the three-dimensional model data visible in the view window corresponding to the view control parameter comprises: controlling according to the current view Parameter analyzing the three-dimensional model data, and acquiring three-dimensional model data visible in a view window corresponding to the current view control parameter;

And analyzing the three-dimensional model data according to the previous view control parameter, and acquiring three-dimensional model data visible in a view window corresponding to the previous view control parameter;

Determining, that the three-dimensional model data visible in the view window corresponding to the current view control parameter is data after the currentization;

Determining that the three-dimensional model data visible in the view window corresponding to the previous view control parameter is the data after the priorization;

The process of analyzing the data after the cylinder and determining the three-dimensional model data that meets the incremental condition as incremental data includes:

Determining the three-dimensional model data in the data of the currentization cylinder and not in the data of the priorization cylinder is incremental data.

The method according to claim 22, wherein, when the incremental data request further comprises: analyzing the three-dimensional model according to the view control parameter when the identification number of the three-dimensional model data is priorized Data, the process of obtaining the three-dimensional model data visible in the view window corresponding to the view control parameter includes:

And analyzing the three-dimensional model data according to the current view control parameter, and acquiring three-dimensional model data visible in a view window corresponding to the current view control parameter;

The process of determining the three-dimensional model data visible in the view window as the post-synthesis data includes: determining that the three-dimensional model data visible in the view window corresponding to the current view control parameter is the current post-booster data;

And discarding the same part of the three-dimensional model data corresponding to the identification number of the three-dimensional model data after the first cylinder in the current data in the incremental data request, and determining the remaining three-dimensional model data. As incremental data.

The method according to claim 22, wherein the analyzing the data after the cylinder and determining that the three-dimensional model data conforming to the incremental condition is incremental data comprises:

And discarding the same data corresponding to the identification number of the three-dimensional model data buffered by the request sending end saved by the request receiving end, and determining the remaining three-dimensional model data as the incremental data. .

26. A progressive transmission device for three-dimensional model data, comprising:

The device according to claim 26, wherein when the requesting sender caches the three-dimensional model data transmitted from the request receiving end, the method further includes: an interpolation module, configured to insert the incremental data into the Requesting data reconstruction in the 3D model data buffered by the sender;

28. A progressive transmission device for three-dimensional model data, comprising:

An acquiring module, configured to analyze three-dimensional model data according to the view control parameter, and obtain the view The 3D model data visible in the view window corresponding to the control parameter;