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Removed tight connections between data structures, auxiliary tools and algorithms in order to create extensible solution, easy for maintenance and improvements; Code is separated on several functional units responsible for specific operation for the sake of simplification of debugging and readability; Introduced new data structures enabling possibility to manipulate discrete model of particular entity (edge, wire, face) in order to perform computations locally instead of processing an entire model. The workflow of updated component can be divided on six parts: * Creation of model data structure: source TopoDS_Shape passed to algorithm is analyzed and exploded on faces and edges. For each topological entity corresponding reflection is created in data model. Note that underlying algorithms use data model as input and access it via common interface which allows user to create custom data model with necessary dependencies between particular entities; * Discretize edges 3D & 2D curves: 3D curve as well as associated set of 2D curves of each model edge is discretized in order to create coherent skeleton used as a base in faces meshing process. In case if some edge of source shape already contains polygonal data which suites specified parameters, it is extracted from shape and stored to the model as is. Each edge is processed separately, adjacency is not taken into account; * Heal discrete model: source TopoDS_Shape can contain problems, such as open-wire or self-intersections, introduced during design, exchange or modification of model. In addition, some problems like self-intersections can be introduced by roughly discretized edges. This stage is responsible for analysis of discrete model in order to detect and repair faced problems or refuse model’s part for further processing in case if problem cannot be solved; * Preprocess discrete model: defines actions specific for implemented approach to be performed before meshing of faces. By default, iterates over model faces and checks consistency of existing triangulations. Cleans topological faces and its adjacent edges from polygonal data in case of inconsistency or marks face of discrete model as not required for computation; * Discretize faces: represents core part performing mesh generation for particular face based on 2D discrete data related to processing face. Caches polygonal data associated with face’s edges in data model for further processing and stores generated mesh to TopoDS_Face; * Postprocess discrete model: defines actions specific for implemented approach to be performed after meshing of faces. By default, stores polygonal data obtained on previous stage to TopoDS_Edge objects of source model. Component is now spread over IMeshData, IMeshTools, BRepMeshData and BRepMesh units. <!break> 1. Extend "tricheck" DRAW-command in order to find degenerated triangles. 2. Class BRepMesh_FastDiscret::Parameters has been declared as deprecated. 3. NURBS range splitter: do not split intervals without necessity. Intervals are split only in case if it is impossible to compute normals directly on intervals. 4. Default value of IMeshTools_Parameters::MinSize has been changed. New value is equal to 0.1*Deflection. 5. Correction of test scripts: 1) perf mesh bug27119: requested deflection is increased from 1e-6 to 1e-5 to keep reasonable performance (but still reproducing original issue) 2) bugs mesh bug26692_1, 2: make snapshot of triangulation instead of wireframe (irrelevant) Correction in upgrade guide.
Open CASCADE Technology ======================= This directory contains sources of Open CASCADE Technology (OCCT), a software development platform providing services for 3D surface and solid modeling, CAD data exchange, and visualization. Most of OCCT functionality is available in the form of C++ libraries. OCCT can be best applied in development of software dealing with 3D modeling (CAD), manufacturing / measuring (CAM) or numerical simulation (CAE). License ------- Open CASCADE Technology is free software; you can redistribute it and / or modify it under the terms of the GNU Lesser General Public version 2.1 as published by the Free Software Foundation, with special exception defined in the file OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT distribution for complete text of the license. Alternatively, Open CASCADE Technology may be used under the terms of Open CASCADE commercial license or contractual agreement. Note that Open CASCADE Technology is provided on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND. The entire risk related to any use of the OCCT code and materials is on you. See the license text for formal disclaimer. Packaging --------- You can receive certified version of OCCT code in different packages. - Snapshot of Git repository: contains C++ header and source files of OCCT, documentation sources, build scripts, and CMake project files. - Complete source archive: contains all sources of OCCT, generated HTML and PDF documentation, and ready-to-use projects for building on all officially supported platforms. - Binary package (platform-specific): in addition to complete source archive, it includes binaries of OCCT and third-party libraries built on one platform. This package allows using OCCT immediately after installation. Certified versions of OCCT can be downloaded from http://www.opencascade.com You can also find OCCT pre-installed on your system, or install it from packages provided by a third party. Note that packaging and functionality of such versions can be different from certified releases. Please consult documentation accompanying your version for details. Documentation ------------- Open file doc/html/index.html to browse HTML documentation. If HTML documentation is not available in your package, you can: - Generate it from sources. You need to have Tcl and Doxygen 1.8.4 (or above) installed on your system. and accessible in your environment (check environment variable PATH). Use batch file *gendoc.bat* on Windows or Bash script *gendoc* on Linux or OS X to (re)generate documentation. - Read documentation in source plain text (MarkDown) format found in subfolder *dox* See *dox/dev_guides/documentation/documentation.md* for details. Building -------- In most cases you need to rebuild OCCT on your platform (OS, compiler) before using it in your project, to ensure binary compatibility. Consult the file *dox/dev_guides/building/building.md* for instructions on building OCCT from sources on supported platforms. Version ------- The current version of OCCT can be consulted in the file *src/Standard/Standard_Version.hxx* Development ----------- For information regarding OCCT code development please consult the official OCCT Collaborative Development Portal: http://dev.opencascade.org