Metrixel 2026.3.1 — Mesh-Aware Correction: reduce clipping in retargeted motion, and inspect what remains

2026-09-27

Retargeting motion onto a different character can result in clipping. For example, an arm through the torso, a hand through a leg. All of this typically happens because the pose that worked for the source skeleton may not always fit the target's proportions. Metrixel's version 2026.3.1 adds Mesh-Aware Correction which evaluates retargeted poses against the target character's mesh and applies bounded pose corrections when it finds a verified improvement. On top of that, there is also Clipping Visualisation, which helps to show the parts where clipping remains afterwards.

What's new?

Mesh-Aware Correction

Mesh-Aware Correction searches a deterministic set of pose adjustments and evaluates a shortlist of them against the character mesh. The feature accepts an adjustment only when it improves the measured clipping score while staying inside the foot-contact displacement and joint-delta checks. Otherwise, your original retargeted pose is left untouched. Of course, as with the rest of Metrixel, the feature is available in both GUI and CLI modes: in the GUI it has its own Mesh-Aware Correction section, which works with Motion Retargeting enabled, and on the CLI you add --mesh_aware_correction true.

  • Speed or Accuracy - options are good! A Correction Quality setting (--correction_quality accurate|fast) picks how thoroughly each frame is checked. Accurate is the default option, Fast is preferred on cases such as dense meshes. In our measurement on a 61-frame clip, Fast was 36× faster and had the same worst-case clipping scenarios.
  • Progress you can follow (or cancel if needed). Correction reports its progress frame by frame. If you cancel, the frames already corrected are kept instead of discarding everything.

A new AI. Yes, a local one that runs on your machine; secure and private!

AI rapidly became a buzzword and now a mainstay in our everyday lexicon. However, it is important to know when it is simply a word, a function without any useful application, or with good usage locally instead of your usual massive LLMs. With this version, Metrixel adds machine-learning inference locally on your machine, using GPU acceleration where available: DirectML on Windows, CoreML on macOS, and CUDA on Linux (with CUDA 12.8 and cuDNN 9 installed on the system). Naturally, there is CPU fallback in case you don't have GPU acceleration. All this without setting up Python environments, installing PyTorch, or uploading your assets. We understand and value your privacy and your assets!

A baseline model ships with Metrixel, so inference works offline without a first-run download. Metrixel also checks for compatible model updates in the background, then applies a verified update from the next job onwards.

In 2026.3.1, the shipped model is a learned clipping screener. It runs over finished retargeted clips and estimates any remaining clipping from the pose data. In this release, it works behind the scenes: it does not change your output, and its estimate is not yet shown in the app.

What the model doesn't do: We tested two methods to choose which pose adjustments to check: a learned model to rank them, or a simple fixed selection method. Both used the same geometric checks on the same 58-frame test clip. Then there are the differences:
- The fixed method reduced measured clipping in 51 frames.
- Model-based ranking, on the other hand, achieved no improvement.

As a result, we are using the fixed selection method for Mesh-Aware Correction in this version (2026.3.1). Note that the shipped ONNX model remains active as the learned clipping screen; it is not used to select correction candidates.

Clipping Visualisation — See the clipping, no guesswork.

On top of the usual opaque and wireframe renders of a corrected retarget, Clipping Visualisation writes an x-ray view and a heat map (<frame>_heat.<ext>) highlighting the mesh regions where residual clipping was detected during sampled evaluation. An opaque render can't show clipping at all, because the intersecting geometry sits inside the mesh. The heat map combines sampled frames into one colour field, so it helps you locate the parts of the model worth inspecting. It is not a per-frame depth measurement.

X-Ray rendering option

X-ray output is also a render option in its own right, right next to Wireframe under Orbit Camera in the GUI. On the CLI, it is --xray true. With this option, every frame is written twice: one normal image, and one <frame>_xray.<ext>. It needs no correction pass, no retarget, and no Professional plan; it works on any asset.

The two controls have different reach. X-Ray applies to every render, including plain assets. Clipping Visualisation writes both the x-ray and the heat map, but only for the corrected retarget output. Turning both on doesn't render the pass twice.

Motion Retargeting changes

  • "Contact-aware (Experimental)" is now "Motion Refinement". The option is renamed in the GUI, and the CLI flag is now --retarget_refine. The old --retarget_contact_aware still works for now with a deprecation warning, so do update your scripts.
  • Plan-gated controls are greyed out up front. Motion Retargeting controls are now disabled on plans that don't include it, instead of letting you configure a retarget that is only skipped once rendering starts.
  • Cleaner FBX retargets. Retargeted FBX characters now export a clean skeleton without importer helper bones, and skinned meshes keep their skin intact.

Other small improvements

  • --camera_step 0 now works in CLI mode as shorthand for a single camera angle, matching the GUI's minimum "Views (per orbit)" setting, instead of being rejected. It selects one camera view, not one animation frame.
  • --wireframe true now takes effect from the CLI. It used to be reset to off during start-up after the arguments were read, which meant CLI runs were unintentionally still producing solid renders. The GUI toggle was unaffected.
  • Clearer error messages when a run can't start. A CLI run blocked by another running instance of Metrixel now reports why and exits with an error, instead of silently completing and producing nothing.
  • Linux: --version and --help now work on headless hosts, and the dependency install script covers the Vulkan loader and graphics libraries.

Known limitations

  • Mesh-Aware Correction changes a frame only when a shortlisted adjustment improves the measured score. An unchanged frame does not mean that the pose was already optimal.
  • The heat map is accumulated from sampled frames rather than continuously evaluating every instant of the animation. clipping that occurs only between sampled frames may not appear as a result.
  • The heat map requires diagnostic colour data to be present; without the data, the visualisation passes are skipped.
  • Processing time scales with mesh detail, so very dense meshes can take noticeably longer to correct. Correction Quality Fast is the lever for those.
  • Clipping Visualisation requires Mesh-Aware Correction to be enabled. The X-Ray option, on the other hand, does not require it.

Pricing

Mesh-Aware Correction and Clipping Visualisation are Professional-plan features. These are added alongside Motion Retargeting, Batch Mode, SDF Export, TIFF Export, and USD Animation Export. As usual, their controls are not hidden on other plans, so these features stay visible. They will just be greyed out.

X-Ray is available on every plan, including the free tier (sign-in required, as for every render).

Platforms

- Ubuntu 24.04 / RHEL 9 — x86_64 Architecture. Metrixel-2026.3.1-linux-x64.tar.gz.zip Distribution
  (tarball — bundles EntVista Hub).
- Windows 11 — x86_64 Architecture. .exe Distribution (signed).
- macOS 14 or later — Apple Silicon Architecture. .dmg Distribution (Apple-signed).

Download the latest version from the product page here!