Blender Granny2 Native Addon

Clean-room Blender addon for importing Granny2 .gr2 files. Export support is in progress.

Status

This project is in active development. Current importer support:

• Native section parser and fixup loader.
• Native decompression for raw, Oodle1, known Oodle0 fixtures, BitKnit, and BitKnit2.
• Meshes, UVs, material slots, texture path resolution, vertex groups, and armatures.
• Animation actions from embedded clips or a separate animation .gr2 file.
• Linux-tested. Windows should use the same addon package, but still needs a real Blender smoke test.

Install

1. Download io_scene_gr2-*.zip from a release, or build it:

   python3 tools/package_addon.py

2. In Blender, open Edit > Preferences > Add-ons > Install....

3. Select the addon zip.

4. Enable Import-Export: Granny2 Native (.gr2).

5. Use File > Import > Granny2 (.gr2).

For character animation, select the body .gr2 as the main file and set Animation GR2 to a separate animation file.

Compatibility

One addon package should support Linux and Windows. The runtime importer is Python-only and does not require Wine, Granny DLLs, SDK libraries, or native shared libraries.

Feature	Status
Raw sections	Working
Oodle1	Working on tested corpus
Oodle0	Working on known fixture; broader corpus still needed
BitKnit	Working on generated corpus
BitKnit2	Working on tested corpus
Mesh import	Working
Skeleton import	Working
Animation import	Working, needs broader visual QA
Export	WIP: raw mesh + skeleton + weight .gr2 writer works on local character round-trip

Current exporter writes uncompressed mesh geometry, UVs, material slots, triangle material groups, texture paths/sizes, skeleton names/parents, imported Granny bind transforms, bone bindings, vertex weights, and 16-bit/32-bit triangle indices. Animations and BitKnit2 export are next milestones.

Exported raw files include Granny-compatible file CRCs computed over the section table and following payload bytes.

Exporter also writes a root Models array with model mesh bindings so Granny Viewer can attach exported meshes to a scene model.

Exporter writes ArtToolInfo axis metadata with UpVector=(0, 0, 1), matching Blender/Metin Z-up character data so Granny Viewer can open files upright by default.

Development

Run parser tests:

python3 tests/test_gr2_parser.py

Run Blender smoke import:

blender --background --python tools/blender_smoke_import.py -- --no-textures path/to/file.gr2

Run exporter collection smoke test:

blender --background --factory-startup --python tools/blender_export_collect_smoke.py

Private sample roots are optional. Tests skip unavailable files. To enable local fixture checks:

GR2_SAMPLE_ROOT=/path/to/granny_samples \
GR2_YMIR_SAMPLE_ROOT=/path/to/ymir_samples \
python3 tests/test_gr2_parser.py

Legal

License: MIT.

Do not commit proprietary SDK files, Granny/RAD/Oodle binaries, game client assets, generated corpora from private assets, Ghidra databases, or decompiled source. Research helpers may compare against local private oracles, but the runtime addon must stay clean and redistributable.

☕ Support

_{fuel the reverse-engineering}