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0031136: Modeling Data - BinXCAF persistence loses normals from triangulation-only Faces

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Information about normals are stored in BinOCAF, XmlOCAF, BRep and BBRep (in case of triangulation-only Faces).
Versions of formats have been changed (11 for TDocStd, 4 for BRep Shape and 3 for Binary BRep Shape)
theWithNormals parameter added to BRepTools::Write()
IsWithNormals()/SetWithNormals() function added to BRepTools_ShapeSet
-normals/-noNormals option added to StoreTriangulation DRAW command
-normals/-noNormals option added to writebrep DRAW command
Tests for writing to brep/binary brep/BinXCaf/XmlXCaf added
Test for StoreTriangulation options -normals/-noNormals added
This commit is contained in:
asuraven
2020-11-17 20:37:01 +03:00
committed by bugmaster
parent 6fab0b3428
commit 9f45d35b6b
40 changed files with 703 additions and 209 deletions
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24
dox/specification/brep_format.md
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@@ -54,6 +54,7 @@ The following sample code reads a shape from ASCII file and writes it to a binar
* \<flag\>: = "0" | "1";
* \<int\>: It is an integer number from -2<sup>31</sup> to 2<sup>31</sup>-1 which is written in denary system;
* \<real\>: It is a real from -1.7976931348623158 @f$\cdot@f$ 10<sup>308</sup> to 1.7976931348623158 @f$\cdot@f$ 10<sup>308</sup> which is written in decimal or E form with base 10.The point is used as a delimiter of the integer and fractional parts;
* \<short real\>: It is a real from -3.402823 @f$\cdot@f$ 10<sup>38</sup> to 3.402823 @f$\cdot@f$ 10<sup>38</sup> which is written in decimal or E form with base 10.The point is used as a delimiter of the integer and fractional parts;
* \<2D point\>: = \<real\>\<_\>\<real\>;
* \<3D point\>: = \<real\>(\<_\>\<real)\><sup>2</sup>;
* \<2D direction\>: It is a \<2D point\> *x y* so that *x<sup>2</sup> + y<sup>2</sup>* = 1;
@@ -71,7 +72,7 @@ The following sample code reads a shape from ASCII file and writes it to a binar
\<content type\> = "DBRep_DrawableShape" \<_\\n\>\<_\\n\>;
\<content type\> have other values [1].
\<version\> = ("CASCADE Topology V1, (c) Matra-Datavision" | "CASCADE Topology V2, (c) Matra-Datavision")\<_\\n\>;
\<version\> = ("CASCADE Topology V1, (c) Matra-Datavision" | "CASCADE Topology V2, (c) Matra-Datavision" | "CASCADE Topology V3, (c) Open Cascade")\<_\\n\>;
The difference of the versions is described in the document.
Sections \<locations\>, \<geometry\> and \<shapes\> are described below in separate chapters of the document.
@@ -1436,8 +1437,8 @@ The example record describes a polyline from *m*=2 nodes with a parameter prese
<triangulation records> = <triangulation record> ^ <triangulation count>;
<triangulation record> = <triangulation node count> <_> <triangulation triangle count> <_> <triangulation parameter presence flag> <_> <triangulation deflection> <_\n>
<triangulation nodes> [<_> <triangulation u v parameters>] <_> <triangulation triangles> <_\n>;
<triangulation record> = <triangulation node count> <_> <triangulation triangle count> <_> <triangulation parameter presence flag> [<_> <need to write normals flag>] <_> <triangulation deflection> <_\n>
<triangulation nodes> [<_> <triangulation u v parameters>] <_> <triangulation triangles> [<_> <triangulation normals>] <_\n>;
<triangulation node count> = <int>;
@@ -1445,6 +1446,8 @@ The example record describes a polyline from *m*=2 nodes with a parameter prese
<triangulation parameter presence flag> = <flag>;
<need to write normals flag> = <flag>;
<triangulation deflection> = <real>;
<triangulation nodes> = (<triangulation node> <_>) ^ <triangulation node count>;
@@ -1458,10 +1461,17 @@ The example record describes a polyline from *m*=2 nodes with a parameter prese
<triangulation triangles> = (<triangulation triangle> <_>) ^ <triangulation triangle count>;
<triangulation triangle> = <int> <_> <int> <_> <int>.
<triangulation triangle> = <int> <_> <int> <_> <int>;
<triangulation normals> = (<triangulation normal> <_>) ^ <triangulation node count> ^ 3;
<triangulation normal> = <short real>.
~~~~
**Description**
\<triangulation u v parameters\> are used in version 2 or later.
\<need to write normals flag\> and \<triangulation normals\> are used in version 3.
\<triangulation record\> describes a triangulation *T* which approximates a surface *S*. The triangulation data consist of a node count @f$ m \geq 3 @f$, a triangle count @f$ k \geq 1 @f$, a parameter presence flag *p*, a deflection @f$ d \geq 0 @f$, nodes @f$ N_{i}\; (1\leq i \leq m) @f$, parameter pairs @f$ u_{i}\; v_{i}\; (1\leq i \leq m) @f$, triangles @f$ n_{j,1}\; n_{j,2}\; n_{j,3}\; (1\leq j \leq k,\; n_{j,l} \in \left \{1,...,m \right \}\; (1\leq l\leq 3)) @f$. The parameters are present only if *p*=1. The deflection describes the triangulation deflection from the surface:
@@ -1640,7 +1650,7 @@ An example of section shapes and a whole *.brep file are given in chapter 7 @re
* @f$ f_{1} @f$ -- free;
* @f$ f_{2} @f$ -- modified;
* @f$ f_{3} @f$ -- IGNORED(version 1) \\ checked (version 2);
* @f$ f_{3} @f$ -- IGNORED(version 1 only) \\ checked (version 2 or later);
* @f$ f_{4} @f$ -- orientable;
* @f$ f_{5} @f$ -- closed;
* @f$ f_{6} @f$ -- infinite;
@@ -1827,10 +1837,10 @@ Flags \<edge data same parameter flag\>, \<edge data same range flag\> and \<edg
\<edge data representation data 1\> describes a 3D curve.
\<edge data representation data 2\> describes a 2D curve on a surface.
\<curve values for parameter minimal and maximal values\> are used only in version 2.
\<curve values for parameter minimal and maximal values\> are used in version 2 or later.
\<edge data representation data 3\> describes a 2D curve on a closed surface.
\<curve values for parameter minimal and maximal values\> are used only in version 2.
\<curve values for parameter minimal and maximal values\> are used in version 2 or later.
\<edge data representation data 5\> describes a 3D polyline.