Ep.13 — Custom Mirror Factor
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Overview
Settings that allow manually added controllers (like twin tails or hair) to support Copy · Mirror · Reset just like Biped arms and legs.
Rigging Info registration + Mirror Factor are the key.
Prerequisites
- Complete Space Group + Skin Bone + Ctrl + Quick Connect as in Ep.11
Why It's Needed — Example (Twin Tails)
- Left Arm mirrors correctly with Ani Utils Copy · Mirror.
- Twin1 extending from the head follows the mirror at a strange angle on the opposite side.
Reason: Left-right symmetry requires changing "+angle → -angle" per axis, but the rule differs per custom bone.
This per-axis ±1 rule is the Mirror Factor.
A rigger can set it manually, but it's too complex for animators → use Auto Calculation Mirror Factor to compute it automatically.
Step-by-Step Guide
1. Register Controllers in Rigging Info
Register Ctrl (controllers), not Skin bones — the side that animators move.
- Select all Twin1, Twin2… (custom Ctrl).
- Rigging Info → Add.
- If New Controller etc. appears in the list, you're good.
- If not visible: do Scan → Load then Add again.
2. Update
- Click Update.
- Check if custom names like Twin1 appear in the Settings list.
→ They may not appear before Update.
3. Auto Calculation Mirror Factor
- Open the relevant controller's Settings.
- Run Auto Calculation Mirror Factor.
- Automatic values like "X reversed, Y·Z retained" fill in.
- Freely rotate/move the Left Twin → Copy · Mirror to Right.
- If it's symmetrical like a mirror reflection — success.
Mirror Settings right-click menu
Right-click a controller row to adjust factors and test mirroring quickly.
| Menu | What it does |
|---|---|
| Set Pos/Rot Factor... | Edit Pos / Rot Mirror Factor values manually. |
| Auto Calculate Mirror Factor(s) | Auto-calculate factors for the selection/mapping (same family as step 3). |
| Mirror (Right → Left) | Mirror right pose to left to verify factors. |
| Mirror (Left → Right) | Mirror left pose to right to verify. |
| Reset to Default Pose | Reset selected controllers to the default pose. |
| Exclude from Mirror | Exclude the item from mirroring. |
Only tweak factors manually when Auto is wrong — verify immediately with right-click Mirror L↔R.
4. Verify Reset · Flip Also Work
| Function | Expected Result |
|---|---|
| Reset All | Default pose including Twin |
| Flip Copy | Left-right flip works |
| Selection Flip Copy | Only selected items flip |
→ Can be used with the same feel as Biped bones.
Rigging Info — Other Uses (Reference)
- Reference·animation support — pose saving, etc.
- BipedPlus Mirror / Reset / Picker — mirror·default pose data
(Details in a dedicated Rigging Info tutorial — mentioned in the video)
Routine (Memorize This)
Add custom Ctrl
→ Rigging Info Add
→ Update
→ Auto Calculation Mirror Factor
→ Copy/Mirror test
Notes
- Adding Ctrl without Connect·Space Group → Reset may work but Mirror may feel off.
- Only manually adjust Factor when Auto doesn't match.
- After Picker Scan, connect custom buttons.