Hello GIFTI Team,

I have started updating Caret and the GIFTI Format Document for GIFTI Label Colors and have a few questions.

If a Label is missing color components, how do we color the nodes for this label? Do we use a default color? If so, what color? Or, do we just not apply any coloring to the nodes? My preference is that a default color is used so that the user can see that there is a label associated with a node.

How do we identify nodes that are NOT to be colored? For example, a cortical partitioning scheme may only identify part of the cortex, such as visual areas. In Caret, we use the name "???" to identify nodes that do not receive any coloring. I believe the AFNI palette file uses "NONE" for this purpose. I suppose any label could be used with an alpha of zero. My preference is that we have a name (???, UNIDENTIFIED, NONE) that indicates these unidentified nodes.

John Harwell