Each ray in an IRIS plot corresponds to small window of energy in time (see IRIS Plot Details). You may select a ray and see the corresponding energy in time, or select an interval of time in the waveform and see the corresponding ray:
- Hold Ctrl and left-mouse-click a ray on the IRIS plot, or
- Hold Ctrl and left-mouse-click a time window on the waveform. You may need to zoom in on the waveform before attempting this - note the small markers above the waveform showing the start of each of these windows.
When you select a ray, IRIS will also display the level, direction and time-of-arrival of that ray.
The example below shows the direct sound after being selected. The ray is thicker than the others, and it’s energy in time has been highlighted.
Rays are not necessarily individual reflections. It’s possible that a ray might encapsulate an entire first-order reflection in time, but it might correspond to several, or even hundreds (in a diffuse field). The ray will give the average sound level and direction for all reflections in the corresponding time window.