Interchangeable Lenses Animation

Author: Vincenzo Mossuto Creation Date: 26/09/2025
Last Reviewer: Sara Altomare/Rossana Mazza

See the Changelog for the full history of updates.

This guide covers the operator object.append_intlens (UI menu: Add animated Interchangeable lens armature).

What it does

• Appends a pre-animated armature from animation_path (one of IL_FULL_AN_1.blend, IL_CUT_AN_1.blend).

• Renames the armature and all bones using the current file name prefix to ensure uniqueness.

• Binds selected parts to the correct bones by name matching:

  • FF_* → Frame Front
  • LN_1_* → First Lens
  • LN_2_* → Second Lens
  • SR_* → Screw used to get the center of rotation

• Applies boolean modifiers on _CUT objects before binding.

• Parents everything to the armature and refreshes NLA (tweak enter/exit).

Prerequisites

• These meshes should be selected (names are mandatory):
  • Frame Front: FF_*
  • Screw: SR_*
  • Main Lens: LN_1_*
  • Second Lens: LN_2_*
• Both lenses needs to be in the same place with the origin in the same coordinate.

Steps

1. Select all required meshes: FF_*, SR_*, LN_1_*, LN_2_*
2. From Spaarkly 1.0.0 → Interchangeable animation, click Add animated Interchangeable lens armature and choose a preset.
3. The script:
   • Appends the rig and renames it (object + armature data) using the current .blend file name as prefix.
   • Renames all bones with the same prefix for uniqueness.
   • For each selected mesh:
     • If it has _CUT and a Boolean modifier, the modifier is applied first.
     • Creates a Vertex Group with the target bone name; assigns all vertices; removes any other groups.
     • Parents the mesh to the armature (Armature Deform).
   • Performs an NLA tweak enter/exit to refresh.

Troubleshooting

• “Frame front / Screw / Main lens / Second lens not found.”
  → Confirm names and that the meshes were selected when running the operator.
• “Interchangeable lens file not found.”
  → Check animation_path and the existence of the chosen .blend library.

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