RealIndex

Drop it in the folder. It shows up in Blender.

RealIndex is a Blender 5.2 LTS extension that turns one folder on disk into a living asset library. Download a model from Sketchfab, a texture set from ambientCG or Poly Haven, or an HDRI, drop it (zipped or not) into your RealIndex folder, and a few seconds later it is in Blender's Asset Browser with a thumbnail, ready to drag into the scene. No importing, no marking as asset, no saving library files, no manual previews. Your downloaded files are never modified.

Five-minute walk-through

1. Install realindex-1.1.0.zip from the latest release (Edit > Preferences > Get Extensions > Install from Disk) and enable it.
2. Set up in the 3D Viewport sidebar (N) > RealIndex > Set Up RealIndex. It creates Documents/RealIndex with Models, Materials, HDRIs and Inbox, and registers two asset libraries: RealIndex (your converted downloads) and RealIndex Files (the folder itself, for .blend files whose assets are already marked).
3. Drop a download anywhere in the folder:
   • into Inbox or loose: RealIndex works out what it is and files it under Materials/ambientCG, Models/Sketchfab, HDRIs/Poly Haven, ... (Inbox items are moved there; every move is logged and can be undone from the panel);
   • into your own subfolder such as Models/Furniture/Chairs: that folder path becomes the catalog;
   • zipped or not: zips are extracted to a cache, the zip itself is left alone.
4. Keep working. The Asset Browser header shows RealIndex: 3 new, converting 1 of 3. Conversion runs in background Blender processes; Blender never freezes.
5. Use it. Open the Asset Browser, pick the RealIndex library, drag a model into the scene, a material onto an object, an HDRI into the viewport. Or assign a shortcut to Quick Place (Preferences > Add-ons > RealIndex): type a few letters and place at the surface under the mouse.

Rename or move a file and the asset follows (no reconversion). Replace a texture and the asset updates. Delete a file and its asset is hidden, then removed once you confirm in the panel.

What can be dropped

Download	Becomes
Texture sets (a folder or zip of _Color, _Roughness, _Normal, _arm_, ... maps)	A material: Principled BSDF, correct colour spaces, gloss inverted, DirectX normals flipped, ARM/ORM split, real-world scale from the name (2m, 150cm), square pixels on non-square maps. Height becomes true displacement for Cycles (see below); specular, transmission, subsurface, translucency and sheen/fuzz maps feed their Principled inputs
HDRIs (.hdr, .exr, about 2:1)	A world: Environment Texture with a rotation value and strength
Models: .fbx, .obj+.mtl, .gltf, .glb, .usd*, .abc, .stl, .ply	A collection (or object) asset: unit mistakes fixed, origin at the bottom centre, textures relinked even when the names in the file do not match, LOD0 kept
.blend files	Marked assets: shown as they are in RealIndex Files. Unmarked: their top-level collections become assets
ambientCG, Poly Haven, Sketchfab, marketplace packs	Recognised: names, resolutions, previews, licences (CC0, or read from Sketchfab's license.txt)

Anything RealIndex cannot use (an unsupported format, a corrupted zip, a texture set without a colour map) is listed under Problems in the panel with the reason, Retry and Ignore. Per asset you can override detection (Texture Set, Model, HDRI, Ignore), reconvert, show the source file, star it and edit its tags.

How texture sets are wired

RealIndex builds materials for Cycles the way the vendors' own Blender files do, and uses every map it finds:

Map	Goes to
Color / Albedo / Diffuse	Base Color (sRGB)
Roughness, or Gloss inverted	Roughness
Metallic, or the B channel of ARM/ORM	Metallic
Normal (OpenGL; DirectX green flipped)	Normal Map node
Height / Displacement	True displacement: Displacement node into the material output, object space, midlevel 0.5, smooth (cubic) sampling. The scale is the vendor's own value when its .blend sits beside the maps (Poly Haven tunes it per material), otherwise 3% of the texture's real-world size
Specular	Specular IOR Level. Spec/gloss maps (reflectance stored as sRGB, about 0.22 for non-metals, as Megascans ships them) are converted (x 12.5); game-engine "specular level" maps (0.5 = default) go straight in. The map's own values tell the two apart
Opacity / Alpha / Mask	Alpha
Emission	Emission Color
Transmission	Transmission Weight
SSS / Subsurface	Subsurface Weight
Translucency	Thin Wall on, Subsurface Weight (light through leaves and paper)
Sheen / Fuzz	Sheen Weight
AO, Cavity	Recognised, not wired: Cycles traces occlusion itself (Multiply AO into Color in the preferences if you want it)

Displacement needs geometry to move. Quick Place adds an adaptive Subdivision modifier when it puts a displaced material on objects; for materials dragged from the Asset Browser, click Set Up Displacement in the RealIndex sidebar tab. Cycles then dices the mesh to about one pixel at render time (Blender 5.0+, no experimental settings). The same tab has the material's Displacement and Midlevel values. With a normal map the material uses Displacement Only (the normal map carries the fine detail); without one it uses Displacement and Bump. Prefer bump only? Set Height Maps to Bump Only in the preferences and click Rebuild Library.

Where things live

• Your drop folders are only read (Inbox filing excepted). One thing to know: Cycles' Texture Cache with Auto Generate (Blender 5.2) writes blender_tx/ folders next to every image it renders, which includes your drop folders. To keep them out, point the texture cache location to an absolute folder in Blender's preferences.
• Each drop folder has a library folder (default %LOCALAPPDATA%\RealIndex\libraries\<folder>-<hash>): the index, extracted zips, previews and one small .blend per asset referencing your textures. It is safe to delete: Rebuild Library recreates it with the same catalogs. Pick a local disk for it in Preferences to keep an external drive's library browsable while unplugged.
• Publish as Remote Library writes a packed, self-contained copy plus Blender's listing, ready for any static web server (Blender 5.2 remote libraries).

For other add-ons

<RealIndex module>.api offers texture_sets(), models(), hdris() and find(query): plain dicts with names, paths, previews, tags and, for texture sets, the detected maps and real-world size. RealWorn's Load Texture library lists RealIndex texture sets when both are enabled.

Performance

Measured on a Ryzen 7 6800HS laptop (RTX 3060, NVMe, Windows 11, Blender 5.2.1) with real CC0 downloads, four workers and the default 2 s poll. "Visible" means the asset file is in the library.

Measure	Budget	Result
ambientCG 2K zip, drop to visible (vendor preview)	10 s	4.8 s
Poly Haven 2K texture set, drop to visible (rendered preview)	20 s	7.1 s
glTF model, 50k triangles, drop to visible	30 s	7.3 s
4K HDRI, drop to visible	10 s	5.0 s
50 mixed downloads (55 assets)	5 min	43 s
Library size vs drop folder	under 5%	1.7%
Poll of an unchanged 10,000-file folder	100 ms	36 ms
Blender UI time per RealIndex timer tick	50 ms	0.13 ms
Quick Place search over 10,000 assets	100 ms	24 ms

On a busy machine conversions take longer; they never block Blender (workers run at below-normal priority).

Development

Requirements: Blender 5.2 (set BLENDER_BIN in the environment or in a .env file at the repository root) and Python 3.11+ with pytest and Hypothesis for the pure suite.

python -m pytest tests/pure                                   # detection, sync, safety (no Blender)
"$BLENDER_BIN" -b --factory-startup --python scripts/setup_test_env.py   # once: pytest for Blender's Python
"$BLENDER_BIN" -b --factory-startup --python tests/run_tests.py          # every suite, real workers
python tests/corpus/fetch.py                                  # optional: real CC0 downloads
python scripts/perf.py                                        # performance on those downloads
python scripts/dev_detect.py FOLDER                           # what detection makes of any folder
python scripts/package.py                                     # dist/realindex-1.1.0.zip

Test fixtures are generated from code (tests/fixtures/make_downloads.py): every vendor quirk, model format and broken download the detector has to handle, with golden results in tests/golden/. Regenerate goldens after a deliberate detection change with RI_UPDATE_GOLDEN=1 python -m pytest tests/pure/test_detect_golden.py and review the diff.

Layout: realindex/core is pure Python (detection, index, sync engine, worker pool), realindex/worker runs inside background Blender processes (importing, building materials and worlds, previews), the rest is the add-on UI.

See CONTRIBUTING.md for setup, the rules the code keeps and how detection changes are tested. Changes are listed in CHANGELOG.md.

Licence

GPL-3.0-or-later. Fixtures are generated; the optional corpus downloads are CC0 (ambientCG, Poly Haven).