Disable TetGen spinner in non-interactive environments

Wrap the tetrahedralize spinner loop in a sys.stdout.isatty() check so that interactive terminals still show progress, but CI/redirected output simply waits on the worker process without frequent stdout updates.

This removes any potential overhead from the progress bar on Windows and macOS runners while TetGen runs in the background, confirming that spinner output is not contributing to slow tetrahedralization in CI.

Author: zasexton

svv/domain/routines/tetrahedralize.py

@@ -150,50 +150,57 @@ def tetrahedralize(surface: pv.PolyData,
             text=True,   # decode to strings
         )
 
-        spinner = _spinner_cycle()
-        start_time = time.time()
-
-        # Print label once
-        sys.stdout.write("TetGen meshing| ")
-        sys.stdout.flush()
-
-        # Live spinner loop
-        while proc.poll() is None:
-            # Compute elapsed time
-            elapsed = time.time() - start_time
-            elapsed_str = format_elapsed(elapsed)
-
-            # Build left side message
-            spin_char = next(spinner)
-            left = f"TetGen meshing| {spin_char}"
-
-            # Get terminal width (fallback if IDE doesn't report it)
-            try:
-                width = shutil.get_terminal_size(fallback=(80, 20)).columns
-            except Exception:
-                width = 80
-
-            # Compute spacing so elapsed time is right-aligned
-            # We'll always keep at least one space between left and right
-            min_gap = 1
-            total_len = len(left) + min_gap + len(elapsed_str)
-            if total_len <= width:
-                spaces = width - len(left) - len(elapsed_str)
-            else:
-                # If line is longer than terminal, don't try to be clever; just put a single space
-                spaces = min_gap
-
-            line = f"{left}{' ' * spaces}{elapsed_str}"
-
-            # '\r' to return to the start of the same line and overwrite
-            sys.stdout.write("\r" + line)
-            sys.stdout.flush()
+        show_spinner = sys.stdout.isatty()
+        if show_spinner:
+            spinner = _spinner_cycle()
+            start_time = time.time()
 
-            time.sleep(0.1)
+            # Print label once
+            sys.stdout.write("TetGen meshing| ")
+            sys.stdout.flush()
 
-        # Finish line
-        sys.stdout.write("\n")
-        sys.stdout.flush()
+            # Live spinner loop
+            while proc.poll() is None:
+                # Compute elapsed time
+                elapsed = time.time() - start_time
+                elapsed_str = format_elapsed(elapsed)
+
+                # Build left side message
+                spin_char = next(spinner)
+                left = f"TetGen meshing| {spin_char}"
+
+                # Get terminal width (fallback if IDE doesn't report it)
+                try:
+                    width = shutil.get_terminal_size(fallback=(80, 20)).columns
+                except Exception:
+                    width = 80
+
+                # Compute spacing so elapsed time is right-aligned
+                # We'll always keep at least one space between left and right
+                min_gap = 1
+                total_len = len(left) + min_gap + len(elapsed_str)
+                if total_len <= width:
+                    spaces = width - len(left) - len(elapsed_str)
+                else:
+                    # If line is longer than terminal, don't try to be clever; just put a single space
+                    spaces = min_gap
+
+                line = f"{left}{' ' * spaces}{elapsed_str}"
+
+                # '\r' to return to the start of the same line and overwrite
+                sys.stdout.write("\r" + line)
+                sys.stdout.flush()
+
+                time.sleep(0.1)
+
+            # Finish line
+            sys.stdout.write("\n")
+            sys.stdout.flush()
+        else:
+            # Non-interactive environment (e.g., CI): just wait for the
+            # worker process to finish without a live spinner to avoid
+            # any potential overhead from frequent stdout updates.
+            proc.wait()
 
         # Collect output (so the pipes don't hang)
         stdout, stderr = proc.communicate()