Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
The Radiance measure published on the BCL is limited to working with the illuminance map data only, and as such it's limited to rectilinear grids. And the sDA reporting is fixed per the LM-83 standard, as you state. These are both limitations (among others) that we acknowledge in various publications about the Radiance work; there is no funding to make these improvements internally.
The beauty of the OpenStudio measure system and API is that you can easily(?) improve these capabilities yourself.
The calculation points for the Radiance measure are derived from the illuminance maps, but you could write your own function to rewrite them based on the geometry or whatever, and let the Radiance measure use those instead. Same for the metrics calculations; those happen downstream from the OpenStudio model so you could change the metrics report function to use different parameters, or make it an input (the sDA setpoint and hours are hard coded, but the others are automatically based on the daylighting control setpoint). The metrics functiom simply works on the points that are supplied to it, so if you rewrote the points files with points covering the real area(s), it'd be none the wiser, and you'd get valid, truly representative spatial daylight metrics. The big missing piece is lack of support for the 5-phase calculation method, which you kinda need for the ASE calculation. This is a bigger lift, unfortunately.
