0027191: Documentation - redesign of information architecture -- revision (user guides) Revision of User Guides - Changes in User Guides Section to correspond with OCCT Overview structure: Mesh became a direct subsection of User Guides (it was a part of Modeling Algorithms). TObj is included into OCAF. - Changes in User Guides – Modeling Algorithms section: Fillets and Chamfers, Offsets, Drafts, Pipes and Evolved shapes, Sewing, Features, 3D Model Defeaturing, 3D Model Periodicity, Object Modification are moved into The Topology API section. - Changes in User Guides – Modeling Data section: Naming shapes, sub-shapes, their orientation and state section is renamed to Shape content. Shape Location is moved into Shape content section. Storage of Shapes is moved into BRep Format section of Specification. Lists and Maps of Shapes subsection is moved into Topology - Exploration of Topological Data Structures. - Some pictures in User Guides (Foundation Classes, Modeling Data, Modeling Algorithms) and Tutorial are updated to improve quality and correct mistakes.

0028089: Mesh - New algorithm for triangulation of 2d polygons Added custom meshing core algorithm to generate base mesh using Delabella library, which can be enabled via IMeshTools_Parameters::MeshAlgo option or CSF_MeshAlgo environment variable. Do not fill cirles filter upon explicit initialization. Call base postProcessMesh functionality after initialization of circles in BRepMesh_CustomDelaunayBaseMeshAlgo. Added Vsprintf() wrapper for vsprintf() preserving C locale.

0031002: Documentation - update Overview for 7.4.0 Updated OCC logo. Replaced some external links to https. Added references to VS2019 support. Added glTF, OBJ, IFC, JT into listing within appropriate sections. Replaced dead URLs. Fixed misleading information.

0029692: Add functionality to make the group of touching same-dimensional shapes connected Implementation of the new class *BOPAlgo_MakeConnected* for making the group of touching same-dimensional shapes connected. Provide the material association for the first sub-elements of the input shapes. Provide possibility to make the connected shape periodic. Draw commands for new algorithm: * makeconnected - make the input shapes connected or glued, performs material associations; * cmaterialson - returns the materials located on the requested side of a shape; * cmakeperiodic - makes the connected shape periodic in requested directions; * crepeatshape - repeats the periodic connected shape in requested directions requested number of times; * cperiodictwins - returns all periodic twins for the shape; * cclearrepetitions - clears all previous repetitions of the periodic shape, keeping the shape periodic. Documentation & test cases for the new algorithm.

0029683: Add functionality to make the TopoDS_Shape periodic in 3D space Implementation of the new class *BOPAlgo_MakePeriodic* for making the shape periodic in 3D space. Periodicity of the shape means that the shape can be repeated in any periodic direction any number of times without creation of the new geometry or splits. The idea of this algorithm is to make the shape look similarly on the opposite sides or on the period bounds of periodic directions. It does not mean that the opposite sides of the shape will be mirrored. It just means the the opposite sides of the shape should be split by each other and obtain the same geometry on opposite sides. Such approach will allow repeating the shape, i.e. translating the copy of a shape on the period, without creation of new geometry because there will be no coinciding parts of different dimension. Draw commands for the new algorithm: * makeperiodic - makes the shape periodic in required directions; * repeatshape - repeats the periodic shape in requested periodic direction; * periodictwins - returns the periodic twins for the shape; * clearrepetitions - clears all previous repetitions of the periodic shape. Documentation & test cases for the algorithm.

0030008: BRepMesh does not respect angular deflection in internal area of bspline surface 1. Check whether the mesh satisfies the required angular deflection has been amended. Namely normals (to the surface) in the ends of any not "frontier" link are made collinear (with the given angular tolerance). 2. New parameters AngleInterior and DeflectionInterior have been added in IMeshTools_Parameters structure. 3. In case of thin long faces with internal edges, add points of internal edges to control parameters using grabParamsOfInternalEdges() in order to avoid aberrations on its ends. Disable addition of parameters from boundary edges in case of BSpline surface. Deviation can be controlled through the deflection parameter. 4. Grab parameters from edges in case if there is just a single interval on BSpline surface along U and V direction.

0026106: BRepMesh - revision of data model 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.

0028747: Incorrect result of the section operation after edge refinement Implementation of the method for simplification of the result of Boolean Operation on the API level. The method BRepAlgoAPI_BuilderAlgo::SimplifyResult has been added, so the derived classes such as BooleanOpeation and Splitter can also use this method. The result shape simplification should be called after the operation is done. The simplification is performed by the means of ShapeUpgrade_UnifySameDomain algorithm. Draw command "bsimplify" has been added to control the simplification options. Documentation for new functionality and draw commands controlling the options of Boolean operations. Test cases for the new functionality. Side-effect change: The algorithms in Boolean component have been changed to use the BRepTools_History as a History tool. Now it became possible to disable the collection of shapes modifications during Boolean Operations, which may be useful for performance sake (in draw the option is controlled by *setfillhistory* command). Draw command "unifysamedom" has been changed to accept the angular tolerance in degrees instead of radians.

0029604: Uniform mechanism providing History of shape's modifications for OCCT algorithms in DRAW Implementation of the mechanism for unification of the history commands for all OCCT algorithms. The following Draw commands should be used to track the history of shapes modifications of any operation: - modified - to find the shapes modified from the given shape in the given history. - generated - to find the shapes generated from the given shape in the given history. - isdeleted - to check if the given shape has been deleted during operation. The mechanism allows fast & easy enabling of the DRAW history support for the algorithms supporting the history on the API level (i.e. the algorithm should have the methods Modified(), Generated() and IsDeleted()). To enable the draw history support it is necessary to store the history of the algorithm into the session. For instance: TopTools_ListOfShape Objects = ...; // Objects TopTools_ListOfShape Tools = ...; // Tools BRepAlgoAPI_Cut aCut(Objects, Tools); // Boolean cut operation BRepTest_Objects::SetHistory(Objects, aCut); // Store the history for the Objects (overwrites the history in the session) BRepTest_Objects::AddHistory(Tools, aCut); // Add the history for the Tools To get the stored history in draw the command "savehistory" should be used. It saves the history kept in session into a Drawable object with the given name: # perform cut bcut r s1 s2 # save history of cut savehistory cut_history explode s1 f modified m cut_history s1_1 The Draw History commands of the following algorithms have been removed: - Boolean Operations; - Defeaturing; - Unify same domain; - Sweep; - Thrusections; All these algorithms have been switched to support the new Draw history mechanism. The Fillet and Blend algorithms have been also enabled to support history commands.

0029481: Implementation of the Feature Removal algorithm Implementation of the 3D model De-featuring algorithm intended for the removal of the unwanted parts (or features) from the model consisting of solids. The features can be the holes, protrusions, gaps, chamfers, fillets etc. The algorithm removes all possible requested features from the shape and builds the new shape as a result. The input model is not modified. On the API level the algorithm is implemented in the class *BRepAlgoAPI_Defeaturing*. The actual features removal is performed by the low-level algorithm *BOPAlgo_RemoveFeatures*. Documentation of the new classes. Implementation of the DRAW commands for working with new algorithm. Test cases for the new functionality. Changes in other algorithms used by De-featuring algorithm: - Provide history support for the solids in *ShapeUpgrade_UnifySameDomain* algorithm; - Implementation of the mechanism to merge History of any Algorithm with standard history methods such as IsDeleted(), Modified() and Generated() into *BRepTools_History*.

0028654: Existed tool (gendoc) for generation documentation does not take into account size of images. The parameter defining image width has been added to all figures to improve their layout in PDF documents and tweaked depending on the nature of each image. Additionally, some minor changes improving image and text layout have been introduced. Remove temporary added possibility for setting image width automatically for generation of pdf documentation.

0028347: Reuse OCCT implementation for producing end-user documentation for Products Updated destination directory for generated by gendoc proc pdf files. Added additional option "-update_images_size" for gendoc procedure to update width of images in *.md files during pdf generation for @figure alias. Documentation was updated to use alias @figure instead of outdated @image Added support of svg image format in procedure OCCDoc_UpdateImagesSize. Added generation of overview for product components. Added generation of products refman/chm for each component.

0028605: Improve the algorithm of calculation of valid intersection range of an edge - New method BRepLib::FindValidRange() has been added. It computes the range of the edge not covered by boundary vertices. - The algorithm of calculation of valid intersection range in the class IntTools_ShrunkRange has been corrected to use the new method. - The method BOPTools_AlgoTools::MakeSplitEdge() has been improved to protect against errors in the case of reversed orientation of the input edge. - Two new Draw commands have been added: validrange - it calls the new method BRepLib::FindValidRange(). tolsphere - it shows tolerances of vertices by drawing a sphere around each vertex of the shape. - The test cases "offset shape_type_i_c YE1,YE2" became better. The scripts have been corrected to reflect the new state.

0028426: Implementation of the EdgesToFaces function 1. The two new methods have been implemented: a. BOPAlgo_Tools::EdgesToWires - allows creating planar wires from edges. The input edges may be not shared, but the output wires will be sharing the coinciding vertices and edges. It is possible to skip the sharing if the input edges are already shared by passing the corresponding flag into the method. The input edges are expected to be planar, but the method does not check it. Thus, if the input edges are not planar, the output wires will also be not planar. In general, the output wires will be non-manifold and may contain free vertices. b. BOPAlgo_Tools::WiresToFaces - allows creating planar faces from the planar wires. In general, the input wires are non-manifold and may be not closed, but should share the coinciding parts. The wires located in the same plane and completely included into other wires will create holes in the faces built from bigger wires These two methods combined allow building faces from set of edges randomly located in 3D space. 2. The DRAW command *edgestofaces* has been implemented. 3. The documentation has been updated with the new section in Modeling Algorithms - Topological Tools. 4. Test cases for the issue.

0027383: Modeling - improve handling of regularity on edges 1. There has been implemented calculation of all possible types of continuity for shared edges: * G1 is set if tangential planes are the same for connected faces in each control points through the edge; * C1 is set in addition to G1 conditions if derivatives, orthogonal to the edge on each face, are equal vectors; * G2 is set in addition to G1 if the centers of principal curvatures are the same for connected faces in each control points through the edge; * C2 is set in addition to C1 and G2 if directions of principal curvatures are equal; * CN continuity is set only if both connected faces are based on elementary surfaces (the conditions for this case are similar to C2 continuity). 2. ShapeFix::EncodeRegularity() is merged into BRepLib::EncodeRegularity(). 3. Implemented several test cases to check correct handling of regularity. 4. Fix incorrect usage of BRepLib::EncodeRegularity() in BRepBuilderAPI_Sewing. 5. Implement a method for calculation of regularity on the given list of edges. 6. Documentation updates

0028214: Make the class GeomPlate_BuildPlateSurface accept Adaptor3d_HCurve instead of Adaptor3d_HCurveOnSurface Now, GeomPlate_BuildPlateSurface accepts base class Adaptor3d_HCurve and of course array of Adaptor3d_HCurve. Classes GeomPlate_Array1OfHCurveOnSurface and GeomPlate_HArray1OfHCurveOnSurface have been renamed to GeomPlate_Array1OfHCurve and GeomPlate_HArray1OfHCurve correspondingly. Documentation has been updated. Correction in documentation.

0027954: Create topology-preserving offset computation algorithm New topology-preserving offset algorithm has been added. It allows to construct offset shape of build solid. test cases have been added. Documentation has been updated to be up to date. Minor corrections. Grid is renamed for simplification purposes. Old constructors are restored with Standard_DEPRECATED macros.