Light groups can be set in usd files through arnold attributes arnold:use_light_groups, arnold:light_groups.
However in Hydra they get reset because one of the last things done in our hydra readers is to apply the hydra light groups. If none is present, use_light_groups is disabled in the arnold node, disabling the light groups.
This fails test_0065 in hydra mode
Light groups can be set in usd files through arnold attributes arnold:use_light_groups, arnold:light_groups.
However in Hydra they get reset because one of the last things done in our hydra readers is to apply the hydra light groups. If none is present, use_light_groups is disabled in the arnold node, disabling the light groups.
This fails test_0065 in hydra mode