(Part 2/3) Project 3D part to plane#2002
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antonysigma
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| # Expected DXF output to be identical to SVG output | ||
| exportSVG3rdAngleProjection(drilled, "") | ||
| exportDXF3rdAngleProjection(drilled, "") |
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Help wanted to move this example code to examples/ folder.
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| cq.exporters.exportDXF( | ||
| visible_edges, | ||
| f"{prefix}{name}.dxf", | ||
| doc_units=6, | ||
| ) |
antonysigma
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| hlr = HLRBRep_Algo() | ||
| hlr.Add(shape.val().wrapped) | ||
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| coordinate_system = gp_Ax2(gp_Pnt(), gp_Dir(*projectionDir)) | ||
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| projector = HLRAlgo_Projector(coordinate_system) | ||
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| hlr.Projector(projector) | ||
| hlr.Update() | ||
| hlr.Hide() | ||
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| hlr_shapes = HLRBRep_HLRToShape(hlr) | ||
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| visible = [] | ||
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| visible_sharp_edges = hlr_shapes.VCompound() | ||
| if not visible_sharp_edges.IsNull(): | ||
| visible.append(visible_sharp_edges) | ||
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| visible_smooth_edges = hlr_shapes.Rg1LineVCompound() | ||
| if not visible_smooth_edges.IsNull(): | ||
| visible.append(visible_smooth_edges) | ||
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| visible_contour_edges = hlr_shapes.OutLineVCompound() | ||
| if not visible_contour_edges.IsNull(): | ||
| visible.append(visible_contour_edges) | ||
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| hidden = [] | ||
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| hidden_sharp_edges = hlr_shapes.HCompound() | ||
| if not hidden_sharp_edges.IsNull(): | ||
| hidden.append(hidden_sharp_edges) | ||
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| hidden_contour_edges = hlr_shapes.OutLineHCompound() | ||
| if not hidden_contour_edges.IsNull(): | ||
| hidden.append(hidden_contour_edges) | ||
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| # Fix the underlying geometry - otherwise we will get segfaults | ||
| for el in visible: | ||
| BRepLib.BuildCurves3d_s(el, TOLERANCE) | ||
| for el in hidden: | ||
| BRepLib.BuildCurves3d_s(el, TOLERANCE) |
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Help wanted to reduce duplicated code.. This part is 90% similar to the code in exporters/svg.py, so it would be better if we can consolidate it.
Also, should I create a new file occ_impl/projection.py? Or, should I move it to occ_impl/geom.py?
Simulate the API from Build123d `project_to_viewpoint`: Given a 3D vector representing the camera position pointing at the origin `(0,0,0)`, render all visible edges/arcs/splines representing the outline of the 3D part projected to the camera. Also render all hidden edges/arcs/splines. Provide and example script `tests/test_projection.py` where a generic part (A bracket with rounded corners and a countersunk hole) is projected to top view, side view, front view, and orthogonal view, and then exported to DXF 2D drawings. Reference: https://build123d.readthedocs.io/en/latest/tech_drawing_tutorial.html
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Simulate the API from Build123d
project_to_viewpoint: Given a 3D vector representing the camera position pointing at the origin(0,0,0), render all visible edges/arcs/splines representing the outline of the 3D part projected to the camera.Also render all hidden edges/arcs/splines.
Provide and example script
tests/test_projection.pywhere a generic part (A bracket with rounded corners and a countersunk hole) is projected to top view, side view, front view, and orthogonal view, and then exported to DXF 2D drawings.Reference: https://build123d.readthedocs.io/en/latest/tech_drawing_tutorial.html
Expected output from
tests/test_projection.py:Follow-up of MR #2001 .
Related to: #122, #1767