File Formats

(3d Editor)

Open and save 3d files from the 3d editor window. The 2d layout window uses a different set of formats (GDSII, OASIS, …). DXF exists in both; the same file opens flat in the layout window and as volume in the 3d editor, depending on which window issues the command.

Solids (OCCT) keep a true volume for STEP and BREP. Meshes are triangle surfaces. On mesh export, solids are tessellated first. Unknown extensions on Save write a screenshot of the current view (PNG and other Qt image formats).

Rhino 3DM is no longer supported. Use STEP for CAD solids or 3MF/STL for meshes.

File Format	Import/Read	Export/Write
3MF
BREP
DXF
GDS3D
OBJ
OFF
PLY
POV	-
STEP
STL
WRL

3MF

3D Manufacturing Format (*.3mf). The file is a ZIP package with a core 3dmodel.model. Coordinates are stored in micrometres. Roundtrip restores meshes, display colours and LayoutEditor layers (le:<index> on the material name). Use 3MF when you need a mesh with colour and layer, for example for printing or exchange with mesh CAD. (introduced with release 20260829)

BREP

Native Open CASCADE shape (*.brep). Units in the file are millimetres, converted with the 3d editor database units (same factor as STEP). Roundtrip is intended for OCCT solids; meshes are converted to shapes on write. Useful as a debug or kernel-level exchange next to STEP. (introduced with release 20260829)

DXF

The same DXF file opens in both windows: open it in the 2d layout window to get flat elements, or in the 3d editor to get volume. The window that issues the command decides. The unit handling is identical to the 2d DXF; the $INSUNITS header is honoured on read and written on export.

In the 3d editor a much wider range of entities is imported than before. Surface geometry comes from 3DFACE, polyface and polygon meshes (POLYLINE with the mesh flags) and the MESH entity, all turned into triangle meshes. Flat entities that carry a thickness are extruded into that height, so a closed LWPOLYLINE, POLYLINE, CIRCLE, ARC, SOLID or TRACE becomes a real Open CASCADE solid that keeps a true volume for STEP and BREP. The extrusion follows the entity elevation and the object coordinate system (extrusion direction, group code 210), so tilted profiles stay correct. A flat entity without thickness is imported as a zero-height face. ELLIPSE and SPLINE are evaluated to curves (the spline through the same NURBS solver used in 2d), so they extrude like any other profile. A spatial spline or 3d polyline keeps the individual z of every vertex, so an extruded 3d path follows its true height instead of being flattened to one plane. Blocks and inserts are kept as hierarchy: each BLOCK becomes a cell, each INSERT a cell reference with its scale, rotation and, for MINSERT, the row and column array. Colours follow the usual DXF rules, taking the layer colour for BYLAYER, the block colour for BYBLOCK, an explicit ACI index, or a true colour when present. Entity types that have no volume meaning, such as REGION or 3DSOLID, are listed in the report and skipped.

Coordinates are stored as integers, so the DXF unit decides how large a drawing may be. When a drawing reaches beyond that range, the affected coordinates are clamped and the report shows a strong warning; choose a coarser DXF unit in the setup and open the file again to get it faithfully. Very large filled outlines (more than 20000 points after arcs are resolved) are skipped as a face and counted in the report, so a bulge-heavy border cannot stall the import.

When the same file is opened in the 2d layout window instead, the thickness and elevation are ignored and only flat 2d elements are created. One convenience applies here: if a file opened from the 2d window clearly contains genuine 3d geometry (a 3DFACE, a mesh or a 3d solid) that cannot be shown sensibly in 2d, the 3d editor is opened and the file is read there. Plain wires — lines, arcs, polylines, splines — do not trigger this even when they carry a z coordinate or a thickness, because dropping that information gives a valid 2d reading. (comprehensive 3d import introduced with release 20260924)

GDS3D

The GDS3D format (*.gds3d) is similar to GDSII. The basic record structure is identical. The main difference is an additional z coordinate on each vertex. It is not a GDSII standard, but it is close to the internal storage format of the 3d editor.

OBJ

Wavefront OBJ (*.obj) with a sidecar MTL file on write (*.mtl next to the OBJ). Triangles and per-object colours are exchanged. Units follow the OFF unit in the setup (or the 3d user units if that setting is 0). (introduced with release 20260829)

OFF

OFF (Object File Format) describes the polygons of a 3d object. Variants *.off, *.coff, *.noff and *.cnoff are recognised. The units used in the file have to be set in the setup (offUnits). Using the wrong setting will result in the incorrect scale of the import/export. A value of 0 uses the 3d user units.

PLY

Stanford PLY, ASCII only (*.ply). Vertex colours are written and read. Binary PLY is not supported. Units follow the OFF unit in the setup, as for OBJ. (introduced with release 20260829)

POV

POV-Ray scene export (*.pov). There is no import. The units used in the file have to be set in the setup (povUnits). The wrong setting will result in an incorrect scale of the export. A value of 0 uses the 3d user units.

STEP

ISO 10303 STEP (*.stp, *.step), written and read with Open CASCADE (XCAF). Solids keep a true volume. Meshes are written as well (not only closed solids). Display colours and LayoutEditor layers are stored and restored on roundtrip. Units in the file are millimetres; LayoutEditor converts with millimetres per database unit (databaseunits × 1000). Open STEP files in the 3d editor, not in the 2d layout window.

STL

STL (STereoLithography / Standard Tessellation Language). ASCII uses *.stl; binary uses *.stlb. There is no colour or layer in STL. The unit in metres is set in the setup (stlUnits); a value of 0 uses the 3d user units.

WRL

VRML 2.0 (*.wrl): meshes with per-shape colours. Import and export use inches (VRML convention, 0.00254 m).