STEP Format

Table of Contents

• Overview
• Scope
• Mapping
  • Import Mapping
  • Product Structure
  • Topology
  • Geometry

Overview

ModelData::ModelReader can read STEP AP203, AP214 or AP242 files.

Scope

Import
B-Rep representations assembly structure PMI

Mapping

Import Mapping

Below tables shows how STEP entities are mapped into MTK entities after import.

Product Structure

STEP Entity	MTK Entity
product_definition	One of: ModelData::Assembly ModelData::Part
next_assembly_usage_occurrence	ModelData::Instance
item_defined_transformation	Geom::Transformation

Topology

STEP Entity	MTK Entity
manifold_solid_brep	ModelData::SolidBody
brep_with_voids
shell_based_surface_model	ModelData::SheetBody
face_based_surface_model
edge_based_wireframe_model	ModelData::WireframeBody
geometric_curve_set
closed_shell	ModelData::Shell
oriented_closed_shell
open_shell
advanced_face	ModelData::Face
face_surface
curve_bounded_surface
face_bound	ModelData::Wire
face_outer_bound
edge_loop
connected_edge_set
composite_curve
boundary_curve
outer_boundary_curve
edge_curve	ModelData::Edge
oriented_edge
vertex_point	ModelData::Vertex

Geometry

STEP Entity	MTK Entity
Surfaces
b_spline_surface_with_knots	Geom::BSplineSurface
rational_b_spline_surface
uniform_curve
quasi_uniform_curve
conical_surface	Geom::ConicalSurface
cylindrical_surface	Geom::CylindricalSurface
offset_surface	Geom::OffsetSurface
plane	Geom::Plane
rectangular_trimmed_surface	Geom::Surface
spherical_surface	Geom::SphericalSurface
surface_of_linear_extrusion	Geom::SurfaceOfLinearExtrusion
surface_of_revolution	Geom::SurfaceOfRevolution
toroidal_surface	Geom::ToroidalSurface
Curves
b_spline_curve_with_knots	Geom::BSplineCurve Geom::BSplineCurve2d
rational_b_spline_curve
uniform_curve
quasi_uniform_curve
circle	Geom::Circle Geom::Circle2d
ellipse	Geom::Ellipse Geom::Ellipse2d
hyperbola	Geom::Hyperbola Geom::Hyperbola2d
line	Geom::Line Geom::Line2d
offset_curve	Geom::OffsetCurve Geom::OffsetCurve2d
parabola	Geom::Parabola Geom::Parabola2d
trimmed_curve	Geom::Curve