# Brain for Blender — model attribution and license

Original model: **Brain for Blender**, by **Anderson Winkler**.

Source and the author's explicit license statement: <https://brainder.org/research/brain-for-blender/>.

Original bilateral pial surface download: <https://s3.us-east-2.amazonaws.com/brainder/software/brain4blender/smallfiles/pial_Full_obj.tar.bz2>.

The original models, the derived geometry in `brain-positions.bin` and `brain-indices.bin`, and the rendered adaptation in `brain-poster.webp` are distributed under the **Creative Commons Attribution-ShareAlike 3.0 Unported license (CC BY-SA 3.0)**.

- License: <https://creativecommons.org/licenses/by-sa/3.0/>
- Full legal text: <https://creativecommons.org/licenses/by-sa/3.0/legalcode>

Retain this attribution and the license link when distributing the mesh or a derivative. Identify modifications, preserve the same license for adapted model contributions, and do not imply the original creator endorses Helpyr or this use. This attribution/license notice concerns the model and derivatives of it; it is not a blanket relicensing statement for unrelated site code or brand assets.

## Reconstruction and modifications

The original author's page describes an openly published human brain model constructed from 12 repeated MRI volumes acquired at the Research Imaging Institute, University of Texas Health Science Center at San Antonio. Cortical reconstruction used FreeSurfer 5.2.0. This is a published scientific/artistic model, not a population-average template. Only the released surface meshes were downloaded; raw MRI acquisitions and personal records were not used.

Preparation for the Helpyr visual prototype on 2026-09-08:

1. Retained both original full pial hemispheres, including their actual asymmetry and surface folds.
2. Reduced the original 289,561 vertices using quadric-error simplification to 39,985 vertices and 79,960 triangles. Removed 20 pairs of coincident, opposing, zero-volume flap triangles and their unreferenced vertices left by reduction.
3. Centered the full bilateral bounding box; scaled uniformly to a width of 3.2 display units; mapped source axes to +X right, +Y superior (up), and +Z anterior (front). Corrected winding after the axis swap.
4. Recomputed area-weighted smooth vertex normals; exported little-endian buffers. All vertex positions and normals are finite; indices are in range; normals have unit length.
5. Created a digital surface-point rendering with a soft animated pulse and a matching static WebP poster. The browser recomputes normals from the distributed geometry; the optional preparation-time normals buffer is not included in this site.

The resulting sculpture and animated signals are an artistic metaphor. The geometry is not offered as a medical diagnostic model, and animation should not be represented as measured brain activity.

## Source integrity

- `lh.pial.obj` SHA-256: `e48056ddf5087eb9a7fe9a75d6c6775ffb853e0a2f4115e31aff5c39467e6ecf`
- `rh.pial.obj` SHA-256: `f6de3057c426f613fa012729e3c193465ca5b332cd45aadbe22288d51dff69d5`

No warranty is supplied by this adaptation. Refer to the Creative Commons license for the original warranty and liability terms.