I used LBNL window to generate a BSDF idf and import the BSDF idf to EnergyPlus.In order to output the hourly BSDF patch number,I set up the output variable "BSDF Beam Direction Number" in EnergyPlus.But output Surface Window BSDF Beam Direction Number was 0 at every hours,Which is why?I have uploaded the idf file and weather file.