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// pybind 11 related includes
#include <pybind11/pybind11.h>
#include <pybind11/stl.h>
namespace py = pybind11;
// Standard Handle
#include <Standard_Handle.hxx>
// user-defined inclusion per module before includes
// includes to resolve forward declarations
#include <Adaptor2d_Curve2d.hxx>
#include <Adaptor3d_Curve.hxx>
#include <Adaptor3d_Surface.hxx>
// module includes
#include <Precision.hxx>
// template related includes
// user-defined pre
#include "OCP_specific.inc"
// user-defined inclusion per module
// Module definiiton
void register_Precision_enums(py::module &main_module) {
py::module m = main_module.def_submodule("Precision", R"#()#");
// user-defined inclusion per module in the body
// enums
//Python trampoline classes
// pre-register typdefs+classes (topologically sorted)
py::class_<Precision , shared_ptr<Precision> >(m,"Precision",R"#(The Precision package offers a set of functions defining precision criteria for use in conventional situations when comparing two numbers. Generalities It is not advisable to use floating number equality. Instead, the difference between numbers must be compared with a given precision, i.e. : Standard_Real x1, x2 ; x1 = ... x2 = ... If ( x1 == x2 ) ... should not be used and must be written as indicated below: Standard_Real x1, x2 ; Standard_Real Precision = ... x1 = ... x2 = ... If ( Abs ( x1 - x2 ) < Precision ) ... Likewise, when ordering floating numbers, you must take the following into account : Standard_Real x1, x2 ; Standard_Real Precision = ... x1 = ... ! a large number x2 = ... ! another large number If ( x1 < x2 - Precision ) ... is incorrect when x1 and x2 are large numbers ; it is better to write : Standard_Real x1, x2 ; Standard_Real Precision = ... x1 = ... ! a large number x2 = ... ! another large number If ( x2 - x1 > Precision ) ... Precision in Cas.Cade Generally speaking, the precision criterion is not implicit in Cas.Cade. Low-level geometric algorithms accept precision criteria as arguments. As a rule, they should not refer directly to the precision criteria provided by the Precision package. On the other hand, high-level modeling algorithms have to provide the low-level geometric algorithms that they call, with a precision criteria. One way of doing this is to use the above precision criteria. Alternatively, the high-level algorithms can have their own system for precision management. For example, the Topology Data Structure stores precision criteria for each elementary shape (as a vertex, an edge or a face). When a new topological object is constructed, the precision criteria are taken from those provided by the Precision package, and stored in the related data structure. Later, a topological algorithm which analyses these objects will work with the values stored in the data structure. Also, if this algorithm is to build a new topological object, from these precision criteria, it will compute a new precision criterion for the new topological object, and write it into the data structure of the new topological object. The different precision criteria offered by the Precision package, cover the most common requirements of geometric algorithms, such as intersections, approximations, and so on. The choice of precision depends on the algorithm and on the geometric space. The geometric space may be : - a "real" 2D or 3D space, where the lengths are measured in meters, millimeters, microns, inches, etc ..., or - a "parametric" space, 1D on a curve or 2D on a surface, where lengths have no dimension. The choice of precision criteria for real space depends on the choice of the product, as it is based on the accuracy of the machine and the unit of measurement. The choice of precision criteria for parametric space depends on both the accuracy of the machine and the dimensions of the curve or the surface, since the parametric precision criterion and the real precision criterion are linked : if the curve is defined by the equation P(t), the inequation : Abs ( t2 - t1 ) < ParametricPrecision means that the parameters t1 and t2 are considered to be equal, and the inequation : Distance ( P(t2) , P(t1) ) < RealPrecision means that the points P(t1) and P(t2) are considered to be coincident. It seems to be the same idea, and it would be wonderful if these two inequations were equivalent. Note that this is rarely the case ! What is provided in this package? The Precision package provides : - a set of real space precision criteria for the algorithms, in view of checking distances and angles, - a set of parametric space precision criteria for the algorithms, in view of checking both : - the equality of parameters in a parametric space, - or the coincidence of points in the real space, by using parameter values, - the notion of infinite value, composed of a value assumed to be infinite, and checking tests designed to verify if any value could be considered as infinite. All the provided functions are very simple. The returned values result from the adaptation of the applications developed by the Open CASCADE company to Open CASCADE algorithms. The main interest of these functions lies in that it incites engineers developing applications to ask questions on precision factors. Which one is to be used in such or such case ? Tolerance criteria are context dependent. They must first choose : - either to work in real space, - or to work in parametric space, - or to work in a combined real and parametric space. They must next decide which precision factor will give the best answer to the current problem. Within an application environment, it is crucial to master precision even though this process may take a great deal of time.)#");
};
// user-defined post-inclusion per module
// user-defined post
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