Changelog

OpenVAT – Blender 5.0 Compatibility & Animation Data Update

New

Animation Data Panel

A new Animation Data panel has been added.

• Allows you to define animation metadata that is written into the exported JSON:
  • Per-animation name
  • Frame ranges (start/end frames)
  • Loop / non-loop designation
• This metadata is used only by the Unity import pipeline for now.
• This system is designed to let you carve multiple logical clips (idle, run, attack, etc.) out of a single VAT bake.

⚠️ Important behavior notes

• Does not affect encoding: The animation definitions do not change which frames are baked. The full encoding range is still exported.
• No skipping: Defining animations does not “skip” frames in the bake or change how the VAT is generated; it only tags ranges inside the encoded data.
• Global frame ranges: Animation frame ranges are currently global scene frames, not relative to the VAT encoding start frame.

Changes / Fixes

Blender 5.0 Compositor Compatibility

• Updated all compositor access from legacy scene.node_tree to a version-safe path:
  • Blender 5.0+: uses scene.compositing_node_group and CompositorNodeTree.
  • Blender 4.x: still uses scene.use_nodes + scene.node_tree.
• Added helpers to keep behavior identical across versions:
  • get_scene_compositor_tree(...) – returns a valid compositor tree for the current scene.
  • get_compositor_output_socket(...) – returns the correct output node/socket:
    • 5.0: Group Output + interface socket
    • 4.x: Composite node

Alpha Over Node (4.x ↔ 5.0)

• Made the Alpha Over setup fully version-aware:
  • Blender 5.0:
    • Uses the “Straight Alpha” input socket (enabled).
    • Connects via named sockets: Background and Foreground.
  • Blender 4.x:
    • Uses legacy use_premultiply = False.
    • Connects via indexed sockets: inputs[1] (BG), inputs[2] (FG).
• Factor input is normalized across versions (Fac = 1.0), and the Alpha Over output is always wired into the compositor’s final output socket.

Unnormalize Compositing Path

• Updated the EXR unnormalize pass to use the same compositor helpers:
  • Uses get_scene_compositor_tree(...) to obtain a compositor tree in 4.x and 5.0.
  • Sends the final combined RGBA result to the correct compositor output (Group Output in 5.0, Composite node in 4.x).
• This removes crashes related to CompositorNodeComposite being undefined in Blender 5.0 and keeps the unnormalize workflow stable.

Known Limitations

• Animation Data panel
  • Frame ranges are global scene frames, not offset-relative to the VAT bake’s start frame.
  • Only the Unity importer currently reads and uses this metadata.
• Compositor
  • The new compositor API in Blender 5.0 is still evolving; future Blender releases may require minor adjustments, but the current helper-based approach is designed to minimize breakage.

Changelog

Small patch to fix typo causing issue with vnrm exports.

Changelog

OpenVAT v1.0.4 – Release Notes

Release Date: July 5 2025
Status: Stable

Highlights

• Custom Vertex Stream Encoding is HERE
  Bake arbitrary per-vertex attributes over time — any 'float' attribute defined in geometry nodes via 'store named attribute' or attribute output is available to encode.
  Attributes can come from Geometry Nodes, vertex colors, or custom data layers.

• EXR32 Output with Raw (Non-Normalized) Mode
  Export textures in true 32-bit float precision per channel (RGB), with optional non-normalized output.
  Enables direct engine-side sampling of raw float data — ideal for systems like Niagara.

• New Texture Layout: Single Row Mode
  Output layout option where:

  • Width = Vertex Count
  • Height = Frame Count

  Optimized for shader-based sampling and VAT workflows where frame indexing is vertical.

• Expanded Format Options

  • PNG8 – normalized [0–1], 8-bit per channel
  • PNG16 – normalized [0–1], 16-bit per channel
  • EXR16 – normalized [0–1], half-float
  • EXR32 – normalized [0–1], full float
  • EXR32 (Raw) – non-normalized, full float (new)

Improvements and Bug Fixes

• Fixed bug causing error related to Blender default language setting
• Fixed GLB export bug, where export contained extra model data
• Cleaner EXR compression and metadata settings for accurate color space
• Enhanced UI/UX for choosing output format and enabling raw mode
• Smarter resolution and wrapping logic when not using Single Row Mode
• Fixed a bug related to 'Selected' proxy mode

Changelog

OpenVAT v1.0.3 — Release Notes

Release Date: 2025-04-29
Minimum Blender Version: 4.2.0

New Features

• EXR Export Option Export as RGB(half) EXR in addition to the existing PNG option

• RGB (no alpha) Default Export Previously, VATs exported with blank Alpha channel, now all exports strip the Alpha channel for better (RGB) formatting.

• Custom Frame Range Encoding
  Export VATs with precise control over the frame range to encode.

• Deformation Basis Options
  Choose deformation basis from Start Frame, Current Frame, or a Custom Proxy object.

• GLTF Export Support Export model by default as GLTF or GLB (for Godot) or choose to not automatically export a model - handle this yourself after creating the VAT.

• Attribute Stripping Often after creating a VAT, there is no use for vertex data like vertex groups and colors - an option has been added to strip this data from the mesh result, as to not carry unnecessary data.

• Transform Space Control
  Select whether to bake object space or world space deformation into the VAT.

• Target 'Collection Combined' Mode
  Export a combined mesh from all objects in a collection into a single VAT.

• Normal-Safe Edge Splitting (Optional)
  Automatically splits sharp edges for safe per-vertex normal capture without modifying the original mesh.

Improvements

• Refactored and organized code for improved readability and maintainability.
• General stability and execution consistency improvements.
• (functions and methods) for testing and eventual UI integration for custom attribute encoding.

Changelog

• Updated tagline to better reflect the use of this self-contained tool
• Code cleanup and commenting
• Nodes cleanup and commenting
• Improved Normals rendering process
  • Added 'Packed' Vertex Normals method option
  • this option allows for a position and normal map in one export map (still includes functionality to not include normals, or render on a separate map)
• Improved menu layout, tooltips, and user interface
• Caught and removed one unnecessary def
• Stripped and un-grouped enclosed node_groups, so appending does not bring additional node groups - major pass at node restructuring and organization
• Stripped all unnecessary data from resources
• Added delete/purge functionality in cleanup (does not accumulate data when cleanup is enabled)

Changelog

• Updated default path to prompt the user to enter a path
• Updated JSON export to include number of total frames to better communicate with engine shader tools

Changelog

OpenVAT - VAT Encoder Initial Extension Release

-Unity URP shadergraph methods and examples can be found at https://github.com/sharpen3d/openvat.

Full support documentation, breakdowns, walkthrough, Unreal integration and demo files are in process and will be available here. https://github.com/sharpen3d/openvat/blob/0a165933838f013e2b0ef8dc856f68f99b5e7505/README.md

Release Notes:

• Mesh to encode must maintain consistent domain size (vertex, edge, face count and ordering)

• Range finding is rounded for ease of manual engine-shader implementation - may update for better range accuracy, but should not impact quality of encoding.

• VAT and VNRM exports are 16 bit PNG exports and have uncapped size. It is recommended to render at a resolution of 4096 or lower - resolution is calculated within the tool when an object is selected.

• Linear PNGs can become heavy if not monitored because of the lossless quality. These can be managed after the fact with careful compression (the built-in geometry node decoder can help determine quality loss with compression by re-loading in the compressed image after running your compression of choice.)

• Not all animation situations have been tested, but any position/normal information that is accessible in the dependency graph (Geometry Nodes Spreadsheet data) is able to be recorded.