Tendrils

Tendrils are the thin processes that a cell extends to touch, grip or pull during an action. In Arborwake they are rope-like, a few pixels wide, and drawn under the cell's body. A cell never shows tendrils while it walks: movement is the sprite's own animation.

How it works#

One module, microglia_motion.js, owns the physics. It is plain JavaScript with a fixed 1/30 s step, and it never moves the cell itself. The game decides when an action plays and calls the module:

• extend grows a process from the body edge toward a target;
• the process grips there, or only points (for a sweep);
• release lets it hang free briefly, and retract draws it home.

For Turn-based encounters, turns/turn_tendrils.js turns one action into frames. It returns timing marks (contact, gripped, release, done), so the VFX can land exactly on the contact frame. Every rope roots at the acting cell's foot point and reaches the exact target tile.

When a straight reach would touch a wall corner, the rope routes round it. The 2 November sweep of the 17 hand-made rooms found 76,096 legal reaches and no reach left without a rope.

Look and history#

The attachment and follow-through were inspired by the game Carrion (Phobia Game Studio). The code is standard position-based dynamics, not Phobia's code. The tunings are fictional mechanics, not claims about real microglial speed or force.

Astrocyte and oligodendrocyte ropes#

• The astrocyte process (astro_rope.js) is anchored: the astrocyte body never travels. For Link it rises through an opening in the floor and stays up all room with a gentle sway. For the Hearth Calming visit it rises, touches, holds and withdraws once. On 2 November the user chose a lighter lilac (#8a87b8 over #625f8b) in place of a near-black version.
• The oligodendrocyte process (oligo_rope.js) wraps a tract segment in Quiet Tracts. It keeps or retracts. It uses the lighter oligodendrocyte ramp. The lead's audit said "Do not introduce another tendril engine", so this reuses the same rope.

Development#

• In the alpha: the lead's integration pins f81684851, with the turn planner, act.js, astro_rope.js and oligo_rope.js.
• Approved by the user: width B and colours (1 November); the astrocyte colour (2 November); the Quiet Tracts repair art with the real rope (2 November).
• Open: the audit records an intermittent Flow/Pull pixel comparison in the full test suite. It is unresolved evidence, not a clean pass.
• Overworld: an older approved snapshot (vendor pin 9360d2f7) drives Survey, Anchor and Pull and Engulf on the overworld maps.

Gallery#

See also#

• Character sprites
• Astro VFX
• Care VFX
• Flow

Sources#

1. f81684851:art/characters/microglia-motion/README.mdcopy
2. b89f778c2:src/main-game/alpha/public/encounter/src/skills/turns/.pinned/act/PIN.jsoncopy
3. 16c9aab43:art/characters/tract-repair/README.mdcopy
4. docs/ops/agent-messages/2026-11-01-lead-sprite-audit-claude-handoff.md (working copy, not in Git)
5. docs/ops/agent-messages/2026-11-02-lead-full-project-reconciliation-audit.md (working copy, not in Git)
6. docs/ops/agent-messages/2026-11-01-claude-workstreams-todo.md (working copy, not in Git)