83 results about "Boundary representation" patented technology

A mechanism is disclosed for reconstructing trimmed surfaces whose underlying spline surfaces intersect in model space, so that the reconstructed version of each original trimmed surface is geometrically close to the original trimmed surface, and so that the boundary of each respective reconstructed version includes a model space trim curve that approximates the geometric intersection of the underlying spline surfaces. Thus, the reconstructed versions will meet in a continuous fashion along the model space curve. The mechanism may operate on already trimmed surfaces such as may be available in a boundary representation object model, or, on spline surfaces that are to be trimmed, e.g., as part of a Boolean operation in a computer-aided design system. The ability to create objects with surface-surface intersections that are free of gaps liberates a whole host of downstream industries to perform their respective applications without the burdensome labor of gap repair, and thus, multiplies the efficacy of those industries.

A hardware-accelerated method for the rasterization of non-simple polygons is used to generate a trim-texture that is dynamically adapted to the required resolution. This method is combined with a GPU-based tessellation of parametric surfaces and a method to generate non-simple polygons with the required resolution from the parametric trimming curves on the GPU. This way trimming and tessellation of parametric surfaces like rational Bézier and Spline surfaces can be performed on the GPU. The method can also be used for the visualization of 2D boundary data on arbitrary parametric surfaces.

This invention relates to a structure and analysis method for geographical 3-D unified models of water conservancy and water and electricity engineering, which couples multi-source data by the mixed data structure of NURBS YIN and BRep to realize 3-D unified modeling to all modeling objects and analyze said 3-D model including: analyzing the space geographical structure of the coupled multi-source data, carrying out sorted geometry modeling based on the mixed data structure of the NURBS, TIN and the BRep, carrying out Boolean operation based on the space relation among them and analysis and test for reliability to finish the structure of the 3-D unified model and finish the geographical analysis to water conservancy and water electricity engineering.

A method of and apparatus for slicing a three-dimensional object representation into a plurality of layer representations is described, wherein the layer representations are subsequently used to form the object layer-by-layer according to the principles of stereolithography. If not already provided in the object representation, a plurality of layer boundary representations are first formed, and then the boolean difference of successive layer boundary representations are computed to derive boundaries of up and down-facing regions, enabling different cure parameters to be specified for these different regions.

Systems and methods for support structures for additive manufacturing of solid models. A method includes receiving a solid model, for a physical object to be manufactured, that includes a plurality of boundary representation surfaces. The method includes analyzing the b-rep surfaces to generate point samples for potential support locations. The method includes clustering points on the solid model, corresponding to at least some of the point samples, to create support locations. The method includes generating column supports in the solid model that connect to the original solid model at the support locations. The method includes storing the solid model, including the column supports.

It is proposed a computer-implemented method for parameterizing a three-dimensional modeled object for tessellation. The method comprising the steps of providing a boundary representation of the modeled object, the boundary representation comprising geometrical data including parametric surfaces and topological data including a set of faces each defined as a portion of the 2D domain of a respective parametric surface; determining 2D meshes each fitting a respective face; and associating the 2D meshes to the geometrical data of the boundary representation. Such a solution improves the tessellation of a 3D modeled object.

A computer-implemented image processing technique for selectively recovering the features of an original CAD model after the original CAD model has been converted to a digitized image and a new CAD model generated from the digitized image. The original boundary representation provides a template to transform the representation through processing under governance of a programmed processor so as to recover accuracy and reintroduce feature edges and feature corners as well as other detailed features to the CAD model obtained from the digitized image, e.g., to enable detailed features to be retained that would otherwise have been lost due to the lossy conversion into image space. The method operates to better ensure that reconstructed boundary vertices lie on original CAD model surfaces and feature edges and corners are recovered.

A data input means inputs boundary data of an object to a computer, a data converting means converts the boundary data into a triangle patch having a phase, an associating means divides a space into rectangular parallelepiped cells having boundary planes intersecting perpendicularly and associates the cell with a triangle to be included in the cell, a dividing / arranging means divides a triangle patch having a phase and floating in the space at cell faces and keeps all triangles arranged within and on the boundaries of cells, a ridge line integrating means integrates ridges that do not alter the phase, a cell assigning means assigns each triangle and its vertex to a cell with reference to index data of the vertex, and a labeling means sets an attribute value of each cell.

The invention provides a method and a system for lightening a BIM (Building Information Modeling) model. The method comprises the following steps of exporting a first BIM model into a second BIM model and storing component color material information of a component in the first BIM model, wherein configuration requirements for operating and displaying the second BIM model are lower than those for operating and displaying the first BIM model; simplifying a solid mesh of the second BIM model and processing boundary representation to obtain a third BIM model; rendering the third BIM model according to point-line-face information and the component color material information. According to the method and the system, the BIM model can smoothly operate on a mobile terminal after being lightened; economic benefits are greatly improved; social resources are saved; the method and the system not only is perfectly applied in the constructional engineering, but also is applicable to other BIM working platforms and has guiding and leading effects on the future industrial development.

A computer simulation of machining of an object by a motion of a tool is described. The object is represented by a boundary representation (BP) object, wherein the BP object includes a boundary representation of a surface of the object, wherein the motion is represented by a set of swept volumes, wherein the set of swept volumes includes a first set of implicit functions defining a surface of the set of swept volumes. The simulation includes determining a proxy object having a second set of implicit functions defining a surface of the proxy object; simulating the machining of the proxy object with the set of swept volumes to produce a machined proxy (MP) object having a third set of implicit functions defining a surface of the MP object; rendering an image of a Boolean intersection between the MP object and the BP object.

The invention provides a BIM (Building Information Modeling)-based mobile terminal building model rendering performance optimization method and system. The optimization method comprises the following steps: performing lightweight processing on a first BIM to obtain a third BIM; only rendering members visible in the scene camera perspective in the third BIM. The lightweight processing step comprises the following sub-steps: deriving a second BIM from the first BIM, and storing the color material information of members in the first BIM; simplifying a solid mesh of the second BIM, and processing the boundary representation to obtain the third BIM. According to the invention, the problem that the BIM cannot be rendered due to poor mobile terminal hardware performance is solved; the BIM can be rendered on the mobile terminal smoothly.

A software processing apparatus comprising a method for converting arbitrary three-dimensional polygon model data into a mathematically complete topological boundary representation with a determined interior volume such that is sufficiently specified for printing on a three-dimensional printer or similar apparatus without deformation concerning color and surface detail.

Computer implemented methods and systems for CAD data exchange, and in particular for creating boundary representations (“breps”) on a feature-by-feature basis are disclosed. According to an embodiment of the techniques described herein, a parameterized feature from a parametric based design system is exported from a source CAD system (404). Iterative steps and complimentary extraction techniques are employed by one or more processors (452, 456) to create an importable design model of the parameterized feature (433), which is imported into a target CAD system (408). While the techniques can include API (436), pattern matching (440), and user emulation (444) techniques, they include a brep per feature (450) technique. By exporting the brep on a per feature (453) basis from the source CAD system (404), the design intent of a CAD designer can be preserved on importation into the target CAD system (408). In particular, where a parametric representation (433) of the feature fails to import into the target system (408), an unparameterized representation (453) of the feature can be substituted.

It is provided a computer-implemented method for designing a three-dimensional modeled object. The method comprises providing a boundary representation of the modeled object; determining a subset of the set of faces for which the faces are a copy one of another; forming a first group of faces within the subset that form a geometrical pattern; and associating to the first group of faces at least one second group of faces that are, for each face of the second group, adjacent to a respective face of the first group and that are, for each pair of faces of the second group, compliant with the rigid motion that transforms, one into the other, the respective faces of the first group to which the faces of the pair are adjacent. Such a method improves the design of a 3D modeled object.

Methods, systems, and apparatus, including medium-encoded computer program products, for facilitating editing of generative design geometry of physical structures, include a method including: receiving editable smooth surface(s), e.g., a T-Spline, constructed from a mesh obtained using a generative design process; instantiating a parametric feature recipe to connect the editable smooth surface(s) with input solid(s), wherein the parametric feature recipe includes an operation sequence that (i) converts the editable smooth surface(s) into boundary representation format and (ii) combines the boundary representation formatted smooth surface(s) with the input solid(s) to produce a watertight three dimensional model of an object; modifying the editable smooth surface(s) in response to input, while preventing disconnection of the editable smooth surface(s) from the input solid(s); updating a visualization thereof in a user interface; and performing the operation sequence of the parametric feature recipe to produce the watertight three dimensional model of the object.

The invention discloses a method used for simulating fluid flow, and the scope of the fluid flow comprises obstacles represented by irregular boundaries; the method is characterized in that: a structured grid of initial physical space is built, and evolved into a complex structured grid by applying treatment to the irregular boundaries one by one, and every irregular boundary is inserted into the complex structured grid as a zero iso-surface to obtain a complex invisible structured grid (CISgrid for short); a unit vertex of the CISgrid is used as a computational node, a finite difference method is adopted to carry out fluid flow numerical simulation according to node connected regulation. According to effective regulation inside the CISgrid, post-treatment of the fluid flow numerical simulation is carried out. The method solves the problem that the irregular boundaries can not be effectively treated when the fluid flow simulation is directly carried out with the structured grid and the finite difference method, avoids the problem of the introduction of the complex structured grid by the adaptation of an unstructured grid and the complex numerical computation based on the unstructured grid, and effectively improves the efficiency of the fluid flow simulation.

A method of approximating the inner or outer boundary of an iris comprises generating an approximate boundary representation (20) comprising a least squares approximation by a Fourier Series of a function of the angle (θ) about a fixed point (A) of the distance of measured points (10) on the boundary from the fixed point (A). More broadly, the method may be used to approximate the shape of any two-dimensional curve or figure.

It is provided a computer-implemented method for compressing a three-dimensional modeled object, wherein the method comprises providing a boundary representation of the modeled object; determining first data, that describe a mapping from the range of a reference function to the range of another function, and second data, that describe a mapping from the domain of the other function to the domain of the reference function which, when composed with the reference function and the mapping from the range of the reference function to the range of the other function, leads to the same result as applying the other function; and replacing in the geometrical data the other function by the first data, the second data and a pointer to the reference function. Such a method improves the compression of a 3D modeled object.

It is proposed a computer-implemented method for tessellating a three-dimensional modeled object parameterized for tessellation. The method comprises the steps of providing 2D meshes associated to geometrical data of a boundary representation of the modeled object, the boundary representation comprising the geometrical data including parametric surfaces and topological data including a set of faces each defined as a portion of the 2D domain of a respective parametric surface; and determining 3D meshes by evaluating the position of vertices of the 2D meshes on the respective parametric surfaces.Such a solution improves the tessellation of a 3D modeled object.

The present invention relates to a wire-frame-based curved surface body three-dimensional boundary representation (hereinafter referred to as B-rep) model reconstructing method and a device thereof. A wire frame model of a project mechanical part in a three-dimension modeling system can be transferred into a three-dimensional boundary representation (B-rep) model. The wire frame model which is obtained by reconstructing various kinds of views or CAD software drawings and the wire frame model which is reconstructed by a sketch-based intelligent CAD system can also be transferred into the B-rep model by the method. The method is particularly effective for the wire frame model with high precision and complete geometrical and topological information. The method can be widely applied to the three-dimension reconstructing in a project drawing and the CAD software drawing and can also be applied to the fields of industrial automatic production planning and decision, three-dimensional identification and detection, product data management and data base searches,computer auxiliary design and manufacture, etc.

A mechanism is disclosed for reconstructing trimmed surfaces whose underlying spline surfaces intersect in model space, so that the reconstructed version of each original trimmed surface is geometrically close to the original trimmed surface, and so that the boundary of each respective reconstructed version includes a model space trim curve that approximates the geometric intersection of the underlying spline surfaces. Thus, the reconstructed versions will meet in a continuous fashion along the model space curve. The mechanism may operate on already trimmed surfaces such as may be available in a boundary representation object model, or, on spline surfaces that are to be trimmed, e.g., as part of a Boolean operation in a computer-aided design system. The ability to create objects with surface-surface intersections that are free of gaps liberates a whole host of downstream industries to perform their respective applications without the burdensome labor of gap repair, and thus, multiplies the efficacy of those industries.

A method of approximating the inner or outer boundary of an iris comprises generating an approximate boundary representation (20) comprising a least squares approximation by a cosine transform series of a function of the angle (θ) about a fixed point (A) of the distance of measured points (10) on the boundary from the fixed point (A). More broadly, the method may be used to approximate the shape of any two-dimensional curve or figure.

A computer simulation of machining of an object by a motion of a tool is described. The object is represented by a boundary representation (BP) object, wherein the BP object includes a boundary representation of a surface of the object, wherein the motion is represented by a set of swept volumes, wherein the set of swept volumes includes a first set of implicit functions defining a surface of the set of swept volumes. The simulation includes determining a proxy object having a second set of implicit functions defining a surface of the proxy object; simulating the machining of the proxy object with the set of swept volumes to produce a machined proxy (MP) object having a third set of implicit functions defining a surface of the MP object; rendering an image of a Boolean intersection between the MP object and the BP object.

One or more embodiments of the invention provide a method, apparatus, system, and article of manufacture for modifying a three-dimensional model. A composite three-dimensional model is displayed in a computer implemented solid modeling system. The composite model comprises a first primitive and a second primitive. A first face of the first primitive is selected. Once selected, a first boundary representation of the first primitive is modified using the selected first face. Thereafter, a second boundary representation of the second primitive is automatically modified based on the modification to the first boundary representation.

A data input means inputs boundary data of an object to a computer, a data converting means converts the boundary data into a triangle patch having a phase, an associating means divides a space into rectangular parallelepiped cells having boundary planes intersecting perpendicularly and associates the cell with a triangle to be included in the cell, a dividing / arranging means divides a triangle patch having a phase and floating in the space at cell faces and keeps all triangles arranged within and on the boundaries of cells, a ridge line integrating means integrates ridges that do not alter the phase, a cell assigning means assigns each triangle and its vertex to a cell with reference to index data of the vertex, and a labeling means sets an attribute value of each cell.

The embodiments described herein provide devices and methods that facilitate improved input devices. In one embodiment, an input device is configured to determine if a sensed object includes an occluded portion using an image representative of sensor values, determine a portion of the image corresponding to the sensed object, and approximate a boundary representation of the sensed object wherein if the sensed object does include the occluded portion, the boundary representation encompasses at least part of the occluded portion of the sensed object and at least part of a non-occluded portion of the sensed object. The determination of a boundary representation corresponding to a sensed object facilitates improved characterization of the sensed object. For example, the determined boundary representation may be used to more accurately track changes in the position of the sensed object as the sensed object moves out of the sensing region.

A computer system and associated method are provided for formulating a search inquiry. A user interface (UI) accepts commands for selecting a first data object, and a display presents the first data object with a top plane as located within a geometric boundary representation of a virtual object-bearing front surface. The UI then accepts commands for selecting a first feature associated with the first data object. The UI next accepts either a flip object command or a flip surface command. In response to the flip command, the display presents a first data object bottom plane, opposite of the first data object top plane. The UI is then able to accept commands for selecting a second feature associated with the first data object, and construct a search inquiry in response to the first data object, the first feature, and the second feature, which is sent to a search engine.

The invention discloses a multi-perspective gait classification method based on multiple regression. The method comprises the steps that 1 a human body contour is extracted from a gait data set to be classified; two human body area images of inner point representation and boundary representation are constructed, and a hub energy diagram is further generated; 2 a multi-period hybrid gait energy matrix corresponding to each gait image sequence is calculated as a gait feature based on the hub energy diagram of the previous step; and 3 multi-perspective gait classification is converted into multiple regression, and a convolution neural network is constructed for solving. According to the invention, the multi-perspective gait classification method based on multiple regression uses the multi-period hybrid gait energy matrix as the gait feature; accurate gait period segmentation is eliminated; the reliance on gait period segmentation is reduced; multi-perspective gait classification is converted into multiple regression; the convolution neural network is constructed for solving; and the gait classification accuracy is improved.

Some embodiments provide a method for selecting a portion of an image. The method identifies edges in the image. The method defines a border about the portion of the image by using the identified edges. The method represents the border as a deformable curve. In some embodiments, defining the border includes detecting a cursor moving over the image and defining the border along identified edges in the vicinity of the cursor. In some embodiments, the method searches for edges in the vicinity of the cursor and snaps the border to the edges. Identifying the edges of the image includes performing an edge detection algorithm in some embodiments. Identifying the edges further includes performing a de-noise algorithm in some embodiments. In some embodiments, the parametrizable curve is a bezier spline.