Additionally to the standard FreeCAD OBJ exporter, the Arch Workbench features an alternative exporter that exports coplanar faces as whole OBJ faces, instead of triangulating Shape-based objects, like the standard exporter does.
Exporting without GUI
Exporting without the graphical interface is possible from the command line, using the Mesh Workbench exporter only.
In this example, a STEP file is imported, the colors of the Shape are saved, then a mesh is created from it, the colors of the original object are re-applied to the faces of the new mesh, which is then exported to OBJ format. Since this is done with the Mesh Workbench, the result is a triangulated mesh.
import Mesh import MeshPart import Import data = Import.open("example.stp") shape = data.Shape shape_colors = data mesh = MeshPart.meshFromShape(Shape=shape, LinearDeflection=0.1, Segments=True) face_colors = [(0, 0, 0)] * mesh.CountFacets for i in range(mesh.countSegments()): color = shape_colors[i] segm = mesh.getSegment(i) for j in segm: face_colors[j] = color mesh.write(Filename="new_example.obj", Material=face_colors, Format="obj")