In the RIA project, factor levels are defined using two columns in the $level3DT (see $curveID for column names). But the factor levels should be really be defined by the meta data for all gc, which in the case of the RIA project is the sim$gcMetaAllCols. This is not a problem for the results as all the curves are used in the initial set of pixelGroups (so they are all present in the sim$level3DT). This may not always be the case. The SK example (cboisvenue/spadesCBM) uses the $gcMeta. This one can be used as an example.
In the RIA project, factor levels are defined using two columns in the $level3DT (see $curveID for column names). But the factor levels should be really be defined by the meta data for all gc, which in the case of the RIA project is the sim$gcMetaAllCols. This is not a problem for the results as all the curves are used in the initial set of pixelGroups (so they are all present in the sim$level3DT). This may not always be the case. The SK example (cboisvenue/spadesCBM) uses the $gcMeta. This one can be used as an example.