In brief
The simulation stores every geometrically possible reflection with time, direction, brightness and visibility attributes, including occluded and shaded reflections and those outside the field of view. This is why the filters in the report can be changed without simulating again.
All hits from Ch. V.3 are stored per time step, output cell and PV area as reflection events. The output cell is 0.5°, 0.25° or 0.125° in size (Ch. V.2); the evaluation remains on 0.5°. An entry contains:
| Content | Values |
|---|---|
| Time | day of the year, minute of the day |
| Direction | azimuth and elevation of the cell centre as the observer sees it |
| Brightness | luminance and illuminance (stored via the solid angle) |
| Gaze axis | distance to the gaze axis, for points with a field of view |
| Flags | blocked, outside the field of view, shaded, specular |
Reflections that are blocked, shaded or outside the field of view are stored as well. Only in this way can the filters in the report be changed afterwards without re-simulating.
Solar position and vertical extent are not stored in the individual entry but in the summaries per time step and PV area (next paragraph).
In addition, summaries are created per time step and PV area for each of the eight combinations of the three visibility attributes: highest luminance, summed illuminance, vertical extent and smallest distance to the gaze axis. From these, the report evaluates every filter combination cell by cell without reading the raw data again. Annual, monthly and daily values, charts and Excel detail data are based on these summaries.
Very large data volumes per observation point, for instance for observation points directly next to large areas, are not stored completely as raw data. All summaries are then created day by day with the same calculation. The report's view of individual moments recalculates the selected day when needed; if the calculation state (engine version or calculation switches) has changed since the simulation, the report points this out ("Day recomputed with the current calculation state – differs from the annual figures. Re-run the simulation for matching values.").
