The basic process is to calculate the weighted average of the surfaceOutdoorTemp by their corresponding view factors for a given location to get the initial MRT, then add the MRTDelta from the SolarCal component to get a meanRadiantTemperature input that accounts for short-wave radiation.
Here’s an example for HB-Legacy: Hydra Viewer
The SolarCal model, LBT has a better model of short-wave radiation[1], so it’s better to install LBT then use the legacy tools.
[1] Is Legacy better in the field of thermal comfort? - #2 by chris