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