What rupa are experienced by a gandhabba when he/she is in paraloka or by a deva or a brahma? There is no brain to produce vanna, sadda, rasa, ghanda, pottabba rupa.
As I understand all rupa are made of the 4 great elements. Thus even vanna rupa and also cakkhu rupa are made of these 4 great elements. What determines a cakkhu rupa or what is the “addon” here compared to e.g. a photon?