Scenario Zbrush Automation

ZBrush automation (tools and pipeline TD)

An expert ZBrush TD automates with contracts and proof: every file is its own tool, every step is a separate call with a time limit, every output is read back from disk, and a hung plugin costs one file, never the batch. ZBrush has no timeout, no undo control from Python and dialogs that code cannot answer, so the safety lives on the agent side: the runner, the checkpoints, the report. If a sibling skill named here is missing from your available skills, ask the user to install it (npx skills add scenario-labs/skills --skill <name>); unattended, proceed from tool schemas and flag the gap.

REQUIRED BACKGROUND: scenario-zbrush-expert (bridge, zb_launch, zb_ops, zb_audit, review loop, 2026 traps).

Status (2026-09-24, refactor pass 2): every ZBrush call here is not yet run in ZBrush (no session assigned; the README's startup stall is still open). Offline: 56 tests pass (tests/code/zbrush-automation/run_offline.py), including a GoZ reader and writer matching ZBrush's own ZResources/DXFStar.GoZ byte for byte. Live suite: tests/code/zbrush-automation/run_live.sh.

Stance (the expert delta)

• One file, one tool, one step per call. "Only one zscript/plugin can be active at a time, so if your zscript calls someting like UV Mapper control passes to UV Mapper and no more commands will run" (marcus_civis, ZBrushCentral 2014); pressing Decimation Master's Pre-process ended ijacobs' script (2013) and forced cgside into a two-run helper (2022, [00:06:56]). So the batch is an agent-side loop (zb_batch.run_folder) that sends each step as its own bridge call with its own timeout, pings after a timeout, and restarts ZBrush after a hang. One long in-ZBrush script dies with its first stuck plugin. [added design]
• Plugins last, checkpoint first. cgside saves before ProjectAll "since it might crash the program" [00:02:19]. zb_ops.project_all refuses to run without a versioned save and the recipe's project step passes one ({stem}_preproject.ztl), even with save_ztl off. Decimation Master runs last, after every valuable output is on disk, so a hang there leaves a partial file, not a lost one. [added]
• Leave the interpreter as found. ZBrush has one Python for the session and the script folder is not on sys.path (Maxon Style Guide). Send code only through remote_call/zb_launch.run: modules are imported by path, then sys.path, sys.modules, stdout and the working directory are restored, also after an error. End a batch with zb_launch.hygiene() (empty lists).
• Dialogs are the automation killer; budget them before running. A studio dropped ZBrush from its farm over Note dialogs (danvas 2017); "no way to detect whether they succeed or error" (BigRoyNL 2024); "if the export plugin, trigger a popup you are screwed" (m_adam, Maxon 2025). set_next_filename feeds built-in buttons only: FBX ExportImport shows options "You cannot escape" (ferdinand, Maxon 2025) and USD Format ignores the preset (usd-portal). Unattended exports are OBJ or .GoZ by path; has_next_filename() still true after a press means a dialog is probably waiting [added].
• Names are identity. GoZ needs unique names "including between all the loaded Tools" (GoZ docs); Decimation Master caches and UV Master control maps are keyed by the tool name, so a new tool with an old name inherits stale data (plugin docs). Stage each input under a unique, sanitized name before import (stage_input); on this Mac's case-insensitive disk rock.obj and Rock.OBJ are one file [added].
• Learn paths from ZBrush, never guess. Recordings show exact paths and hidden preconditions (Maxon ZScript manual; MadPony DnLlDJxfxHs [00:02:16]); Ctrl+hover shows a path. For an agent the cheapest oracle is ZBrush's own Activity log, which writes every press and set with its canonical path (zb_batch.ActivityWatch; proven by the 05:20 log). Then zb_plugin_ops.probe() confirms exists, range and title.
• Record once, apply to all. Pavlovich replays one recording on every visible SubTool with ZRepeat It [00:37:30]; ZRepeat It is not shipped in 2026.2.1, the Python equivalent is for_each_subtool.
• Files, not live links, between apps. GoZ sends the lowest subdivision level (GoZ docs; FlippedNormals [00:04:02]), updates by name, and raises a reprojection prompt when topology changed. An agent hands over .GoZ or OBJ files plus a manifest and lets the other app's agent import them.

Establish first

Workflow

1. Session and probe. zb_launch.start() or reuse a running bridge; zb_plugin_ops.probe() on every path the recipe uses; memory(). GATE: ping returns 2026.2, every recipe path exists, plugins present.
2. Plan dry. zb_batch.plan(files, out, params) resolves every file's steps, paths and timeouts without ZBrush. GATE: outputs outside the install (read-only since 2026.1), unique stems, no FBX or USD step.
3. Pilot one file, watched. run_folder([f], out, params); open sheet.png and the normal map; import the low and map in the target app (scenario-maya-pipeline-scripting or a Blender skill). GATE: file ok, step timings recorded, map orientation confirmed in the target app (flip V and green are [verify] until then).
4. Run the batch. Bridge mode by default; mode="script" (one ZBrush -script process per file) once live_a05 has shown how ZBrush exits. Drop a STOP file in the output folder to end between files; rerun to resume (sha1 and recipe hash). GATE: report.json written after every file.
5. Recover. For each failed or partial: read steps[].outcome (error, timeout_recovered, hang), the hang evidence (screenshot when the screen is unlocked; ZBrush Notes are drawn in the canvas, only the screenshot shows them), and batch.blocked. Fix params or paths, rerun: finished files are skipped. GATE: every non-ok file has a cause in the report.
6. Review and deliver. Open the contact sheet; check low_audit, preview_audit, normal_stats; write the handoff manifest. GATE: numbers pass, sheet looked at, report and manifest delivered.

Numbers