Rhino 3D Tip: SelSimilar: Rapidly Select and Isolate Objects by Matching Properties

Speed up selection-heavy tasks by finding and isolating related objects in one move. SelSimilar (Select Similar) matches properties of a “seed” object to instantly select all comparable geometry across your model.

• How it works
  • Select a representative object (your seed).
  • Run SelSimilar (type SelSimilar in the command line).
  • Adjust the matching criteria in the command options to refine what “similar” means.
  • Confirm to select all objects that meet those criteria.

Typical criteria you can match include:

• Object type (curve, surface, polysurface, SubD, mesh, dimension, block instance).
• Layer, name, color, linetype, print width, group membership.
• Material or display color assignments.
• Basic geometric status (e.g., open vs. closed, planar vs. non‑planar).

Practical uses

• Model cleanup: Grab every imported polyline on a specific layer to rebuild or simplify.
• Rendering prep: Select all objects using the same material to update PBR settings in one pass.
• Documentation: Round up dimensions using a given style to restyle or rescale.
• Manufacturing: Isolate all closed polysurfaces for export, leaving reference curves untouched.
• QA checks: Highlight all open edges or non‑manifold candidates by combining selection with analysis tools.

Power combos

• Selection hygiene: After SelSimilar, use Isolate or Hide to focus, then Invert to target the remainder.
• Save for later: Convert results into a Named Selection for one‑click recall on complex assemblies.
• Layer workflows: Tighten matching by requiring both Type and Layer—fewer false positives, cleaner edits.
• Filters first: Activate Selection Filter (status bar) to constrain to curves, meshes, or SubD before running.

Tips for reliable results

• Tune tolerance: Similarity checks that rely on geometric status benefit from sensible model tolerances (File > Properties > Units). Small tolerances can fragment results; overly large tolerances can over‑select.
• Blocks: Running on block instances selects other instances of the same definition; edit inside BlockEditor if you need sub‑object similarity.
• Heavy scenes: Work in smaller groups—Use Layer Filters and Named Views to keep viewport responsive while you iterate selections.

Fast access

• Create an alias: Options > Keyboard > Aliases > Add “ss” = SelSimilar, then press Space/Enter.
• Make a toolbar button with a tooltip and macro “! _SelSimilar” to standardize team usage.

Troubleshooting

• Nothing selected: Loosen criteria (e.g., ignore color) or choose a different seed object that better represents the target set.
• Too many selected: Add constraints (Type + Layer + Material) and re‑run.
• Command not found: If your Rhino build doesn’t include SelSimilar, open PackageManager and look for “Select Similar,” or check Food4Rhino. Need guidance or licensing? Visit NOVEDGE.

Level up your selection game and reduce repetitive clicks. For Rhino licenses, upgrades, and expert advice, connect with NOVEDGE, and browse more Rhino tips and solutions at NOVEDGE.

You can find all the Rhino products on the NOVEDGE web site at this page.