feat: add 1d_path mode and DXF export/download support

apps/cad-worker/main.py

@@ -61,7 +61,7 @@ image = (
 # ---------------------------------------------------------------------------
 
 _VALID_MODES = {"part", "assembly", "sketch"}
-_VALID_OUTPUTS = {"3d_solid", "surface", "2d_vector"}
+_VALID_OUTPUTS = {"3d_solid", "surface", "2d_vector", "1d_path"}
 _MAX_PROMPT_CHARS = int(os.environ.get("NATURALCAD_MAX_PROMPT_CHARS", "1200"))
 
 _RATE_WINDOW_SECONDS = int(os.environ.get("NATURALCAD_RATE_WINDOW_SECONDS", "60"))
@@ -401,6 +401,11 @@ _OUTPUT_RULES = {
         "Extrude with a minimal thickness of 1 mm so the geometry exports as STL/STEP. "
         "result must be a Part (bp.part)."
     ),
+    "1d_path": (
+        "Output goal: a 1D path-style layout (linework/centerlines). Build the geometry from lines/arcs on Plane.XY. "
+        "For compatibility with STL/STEP preview, give the path a minimal thickness (about 1 mm) by using a thin profile. "
+        "result must be a Part (bp.part)."
+    ),
 }
 
 _MODE_HINTS = {
@@ -646,7 +651,7 @@ def generate_cad(prompt: str, mode: str = "part", output_type: str = "3d_solid")
         if log_generated_code:
             _log_info(f"Generated code:\n{generated_code}")
 
-        from build123d import export_stl, export_step
+        from build123d import Axis, ExportDXF, Unit, export_step, export_stl
 
         with tempfile.TemporaryDirectory() as tmpdir:
             script_path = Path(tmpdir) / "script.py"
@@ -727,13 +732,14 @@ def generate_cad(prompt: str, mode: str = "part", output_type: str = "3d_solid")
                     }
 
             # ----------------------------------------------------------------
-            # Export: STL, STEP, GLB
+            # Export: STL, STEP, GLB, DXF
             # ----------------------------------------------------------------
             shape = result_shape
             urls = {}
             stl_path = Path(tmpdir) / "output.stl"
             step_path = Path(tmpdir) / "output.step"
             glb_path = Path(tmpdir) / "output.glb"
+            dxf_path = Path(tmpdir) / "output.dxf"
 
             try:
                 export_stl(shape, str(stl_path))
@@ -765,6 +771,24 @@ def generate_cad(prompt: str, mode: str = "part", output_type: str = "3d_solid")
             except Exception as e:
                 _log_error(f"GLB export failed: {e}")
 
+            try:
+                if output_type in {"2d_vector", "1d_path"}:
+                    exporter = ExportDXF(unit=Unit.MM)
+                    if output_type == "1d_path":
+                        exporter.add_shape(shape.edges())
+                    else:
+                        faces = shape.faces()
+                        if faces:
+                            top_face = faces.sort_by(Axis.Z)[-1]
+                            wires = [top_face.outer_wire(), *list(top_face.inner_wires())]
+                            exporter.add_shape(wires)
+                        else:
+                            exporter.add_shape(shape.edges())
+                    exporter.write(str(dxf_path))
+                    _log_info(f"DXF exported: {dxf_path.exists()}")
+            except Exception as e:
+                _log_error(f"DXF export failed: {e}")
+
             # ----------------------------------------------------------------
             # Upload to Supabase storage
             # ----------------------------------------------------------------
@@ -772,6 +796,8 @@ def generate_cad(prompt: str, mode: str = "part", output_type: str = "3d_solid")
                 ("stl", stl_path, "model/stl"),
                 ("step", step_path, "application/octet-stream"),
             ]
+            if dxf_path.exists():
+                file_pairs.append(("dxf", dxf_path, "application/dxf"))
             if store_glb:
                 file_pairs.append(("glb", glb_path, "model/gltf-binary"))
             for fmt, file_path, content_type in file_pairs:

apps/gradio-demo/app/main.py

@@ -40,6 +40,7 @@ EXAMPLE_PROMPTS = [
     ["Industrial notched tower block, 140 mm tall", "part", "3d_solid"],
     ["Smooth roof canopy surface, 200 mm span, shallow rise", "part", "surface"],
     ["Bracket plate profile with 6 holes for a laser-cut sketch", "sketch", "2d_vector"],
+    ["Single-line floor route centerline with 3 jogs, 120 mm long", "sketch", "1d_path"],
 ]
 
 DEFAULT_CODE = '''from build123d import *
@@ -531,7 +532,7 @@ def generate_from_prompt(prompt: str, mode: str, output_type: str):
                 result = json.loads(response.read().decode())
 
                 if "error" in result:
-                    return None, None, None, f"Error from backend:\n{result['error']}", "Backend generation failed."
+                    return None, None, None, None, f"Error from backend:\n{result['error']}", "Backend generation failed."
 
                 urls = result.get("urls", {})
                 code = result.get("generated_code", "")
@@ -540,6 +541,7 @@ def generate_from_prompt(prompt: str, mode: str, output_type: str):
                 glb_url = urls.get("glb")
                 stl_url = urls.get("stl")
                 step_url = urls.get("step")
+                dxf_url = urls.get("dxf")
                 
                 # Download files to artifacts directory (same as local mode)
                 # so Gradio can serve them properly
@@ -550,6 +552,7 @@ def generate_from_prompt(prompt: str, mode: str, output_type: str):
                 glb_file = None
                 stl_file = None
                 step_file = None
+                dxf_file = None
                 
                 if glb_url:
                     glb_path = run_dir / f"{run_id}.glb"
@@ -602,6 +605,23 @@ def generate_from_prompt(prompt: str, mode: str, output_type: str):
                         _log_error(f"STEP download failed: {e}")
                         step_file = None
 
+                if dxf_url:
+                    dxf_path = run_dir / f"{run_id}.dxf"
+                    _log_info(f"Downloading DXF from {dxf_url}")
+                    try:
+                        with request.urlopen(dxf_url) as r:
+                            data = r.read()
+                            _log_info(f"Downloaded DXF bytes: {len(data)}")
+                            if len(data) < 100:
+                                _log_error("DXF file too small")
+                            with open(dxf_path, "wb") as f:
+                                f.write(data)
+                        dxf_file = str(dxf_path)
+                        _log_info(f"DXF saved to {dxf_file}, size {os.path.getsize(dxf_file)}")
+                    except Exception as e:
+                        _log_error(f"DXF download failed: {e}")
+                        dxf_file = None
+
                 if not glb_file and stl_file:
                     try:
                         glb_path = run_dir / f"{run_id}.glb"
@@ -623,32 +643,34 @@ def generate_from_prompt(prompt: str, mode: str, output_type: str):
                 final_summary = f"Model ready!{' · ' + job_id[:8] if job_id else ''}"
                 preview_file = glb_file
 
-                return preview_file, stl_file, step_file, combined_logs, final_summary
+                return preview_file, stl_file, step_file, dxf_file, combined_logs, final_summary
         except error.HTTPError as exc:
             body = exc.read().decode() if exc.fp else ""
             try:
                 detail = json.loads(body).get("error", body) if body else str(exc)
             except Exception:
                 detail = body or str(exc)
-            return None, None, None, f"Backend HTTP {exc.code}: {detail}", "Generation failed."
+            return None, None, None, None, f"Backend HTTP {exc.code}: {detail}", "Generation failed."
         except error.URLError as exc:
             if isinstance(exc.reason, TimeoutError) or "timed out" in str(exc.reason).lower():
                 return (
                     None,
                     None,
                     None,
+                    None,
                     (
                         f"Backend timeout after {BACKEND_TIMEOUT_SECONDS:.0f}s. "
                         "Try a shorter prompt (fewer clauses), or retry."
                     ),
                     "Generation timed out.",
                 )
-            return None, None, None, f"Backend error: {exc}", "Generation failed."
+            return None, None, None, None, f"Backend error: {exc}", "Generation failed."
         except TimeoutError:
             return (
                 None,
                 None,
                 None,
+                None,
                 (
                     f"Backend timeout after {BACKEND_TIMEOUT_SECONDS:.0f}s. "
                     "Try a shorter prompt (fewer clauses), or retry."
@@ -656,7 +678,7 @@ def generate_from_prompt(prompt: str, mode: str, output_type: str):
                 "Generation timed out.",
             )
         except Exception as exc:
-            return None, None, None, f"Backend error: {exc}", "Generation failed."
+            return None, None, None, None, f"Backend error: {exc}", "Generation failed."
     
     # Fallback to local code stub if backend is missing
     spec = {
@@ -667,7 +689,7 @@ def generate_from_prompt(prompt: str, mode: str, output_type: str):
     code = render_code_from_spec(spec)
     combined_logs = f"Local fallback:\n{code}"
     final_summary = "Code generated."
-    return None, None, None, combined_logs, final_summary
+    return None, None, None, None, combined_logs, final_summary
 
 
 def use_example(prompt: str, mode: str, output_type: str):
@@ -693,7 +715,7 @@ def build_ui() -> gr.Blocks:
                 )
                 with gr.Row():
                     mode_picker = gr.Dropdown(choices=["part", "assembly", "sketch"], value="part", label="Mode")
-                    output_picker = gr.Dropdown(choices=["3d_solid", "surface", "2d_vector"], value="3d_solid", label="Output")
+                    output_picker = gr.Dropdown(choices=["3d_solid", "surface", "2d_vector", "1d_path"], value="3d_solid", label="Output")
                 generate_btn = gr.Button("Generate Model", variant="primary")
                 gr.Markdown("### Try one of these")
                 gr.Examples(
@@ -709,6 +731,7 @@ def build_ui() -> gr.Blocks:
                 with gr.Row():
                     stl_download = gr.File(label="Download STL")
                     step_download = gr.File(label="Download STEP")
+                    dxf_download = gr.File(label="Download DXF")
                 status_output = gr.Markdown("Ready. Use the mouse to orbit, pan, and zoom the model.")
 
         log_output = gr.Textbox(
@@ -722,7 +745,7 @@ def build_ui() -> gr.Blocks:
         generate_btn.click(
             fn=generate_from_prompt,
             inputs=[prompt_input, mode_picker, output_picker],
-            outputs=[model_viewer, stl_download, step_download, log_output, status_output],
+            outputs=[model_viewer, stl_download, step_download, dxf_download, log_output, status_output],
         )
 
     return demo