ROI/Cell Mapping -- ##ROI_Boundaries_Format header field and #ROI_Boundaries column

[strambc]

How are we going to capture 3D ROI boundaries in FOF-CT?
Currently, there are two relevant fields in the ROI/Cell Mapping Table:

1. Mandatory Header field: ##ROI_Boundaries_Format=
2. Mandatory Column: #ROI_Boundaries

OME Data Model has a Region of Interest (ROI) model.

However, this is primarily designed for 2D ROIs.

To render a 3D shape, they state the following:

"The current method of defining an ROI in three dimensions is as a Union of Shape objects, each of which defines the geometry to which that 3D ROI would cut the 2D Plane the Shape is attached."

Incorporating support for a 3D ROI specification model is a good idea.

The following suggestions emerged when discussing with Andreas Bueckle at the CFDE Fall Meeting on 2024-10-22.

Most formats record shape data as

1. list of node
2. list of edges
3. List of triangles (for rendering)

Examples

1. glTF
   SPECIFICATIONS: https://www.khronos.org/gltf/#gltf-spec

2. OBJ

[andreasbueckle]

glTF is the format used for specific 3D Reference Objects in the Human Reference Atlas (HRA): https://humanatlas.io/3d-reference-library

It is basically JSON under the hood and also has a binary format called GLB. glTF is used as a runtime format for 3D assets.

[andreasbueckle]

PS: Khronos Group (who specifies and maintains glTF) has a sample gallery here: https://github.com/KhronosGroup/glTF-Sample-Models/tree/main

A representation of a glTF model: https://github.com/KhronosGroup/glTF-Sample-Models/blob/main/2.0/ABeautifulGame/glTF/ABeautifulGame.gltf

Note how JSON is used to denote meshes, scenes, translations, etc.

[strambc]

https://github.com/KhronosGroup/glTF/blob/main/specification/2.0/figures/gltfOverview-2.0.0d.png