Cache Guardian - Simulation Cache Checker

Every simulation-heavy Blender project eventually hits the same failure: a shot renders perfectly at your desk, then comes back broken from the farm, from a collaborator's machine, or from your own file three weeks later. The cause is almost always invisible in the viewport: a cloth sim that never got baked, a fluid domain whose cache files quietly went missing, a rigid body cache left stale after a mass or collision-margin tweak. Blender doesn't warn you. You find out after the render.

Cache Guardian is a standalone add-on built to close that gap. It scans every physics and simulation system in the active scene Cloth, Fluid/Smoke (Mantaflow), Rigid Body World, Soft Body, Particle systems, and Geometry Nodes simulation zones and answers three questions for each one: Is it baked? Does the cache actually exist on disk? Is it stale relative to the settings it was baked with? Results land in a single N-panel dashboard with plain-language explanations and one-click fixes, so cache problems get caught in the viewport instead of in dailies.

It does not depend on, modify, or share code with any other add-on. It reads local simulation settings and local disk cache files only; no network access, no external services, nothing phoning home.

Key Benefits
Eliminate farm-vs-desktop render mismatches. Know before you submit whether every sim in the scene will reproduce on another machine.

Cut QC time from scene-by-scene manual inspection to one click. No more opening every object's Physics tab by hand.

Catch missing cache files before they cost a render. A "baked" flag in Blender doesn't guarantee the cache files are actually there Cache Guardian checks disk, not just the flag.

Protect against silent setting drift. A fingerprint-based staleness heuristic flags when mass, stiffness, resolution, or frame range changed since the last bake.

Avoid cache-path handoff failures. Flags absolute disk paths that won't travel with the .blend to another artist or render node.

Prevent cross-simulation cache collisions. Warns when two sims point at the same custom cache directory — a documented cause of one bake silently overwriting another.

Avoid cloud-sync corruption. Flags cache directories sitting inside Dropbox, Google Drive, OneDrive, or iCloud folders, where sync clients touching files mid-write is a known source of corrupted playback.

Fix issues without leaving the panel. Select Object and Re-bake buttons resolve most flagged items in place.

Get an audit trail. Export Report writes a plain-text report next to the .blend for QC logs, client sign-off, or pipeline records.

Optional pre-render safety net. An auto-check-before-render preference throws a non-blocking warning if unresolved cache errors exist — heads-up, not a gate, so it never interrupts your workflow.

Professional Use Cases
VFX and animation studios running nightly farm renders where a single unbaked or stale cache can cost hours of wasted render time across a render wall.

Freelance 3D artists delivering .blend files to clients or collaborators who need the caches to actually travel with the file.

Technical directors and pipeline TDs building QC gates before shots go to the farm or to publish.

Motion design studios with cloth and particle-heavy scenes where iteration speed depends on knowing which sims still need a rebake.

Archviz and simulation-driven visualization teams using fluid or rigid body sims for hero shots, where a broken cache means a broken client presentation.

Game cinematics and previz teams handing sim-heavy scenes between artists on different machines.

Educators and studio leads onboarding junior artists, using Export Report as a teaching and review tool for simulation hygiene.

Multi-artist collaborative projects where one artist bakes a sim and another opens the file later — Cache Guardian catches the staleness that happens in between.

Workflow Advantages
Replaces a manual, error-prone routine — opening every object, checking the Physics tab, eyeballing bake ranges — with a single scan.

Groups results by simulation type, so a scene with a dozen cloth objects and a fluid domain reads as an organized checklist, not a fishing expedition.

Spot-checks disk cache files across a sampled set of frames (start, end, and interior frames) instead of exhaustively reading every frame, keeping scans fast even on long bakes.

Surfaces frame-range coverage gaps automatically — a bake that stops five frames short of the render range is a common, hard-to-spot cause of last-frame render failures.

Reduces back-and-forth with render wranglers and pipeline support by catching path portability and shared-directory issues before a submission, not after a failed job.

Keeps QC inside Blender's native UI — no external tool, no separate license server, no round-trip to another application.