QUESTION:

I am doing some research into light pipes and their use in re-directing sunlight to the interior of deep plan buildings. I saw the option in ECOTECT to see the solar rays but I get confused with this option.

Is there any way to select only one ray (always the same ray) and track it's path and bounces in my different light pipe designs ?

ANSWER:

Yes this is possible.

Firstly, to set up solar rays you need to tag one (or several) objects in your model as a reflector.

This "reflector" will be used to see the solar rays reflected -- that is, only rays from the sun passing through this object will be displayed (or reflected) within your model.

To tag an object as a reflector, select it within your model, go to the Shadow Settings panel, click the Reflector button in the Tag Object(s) As section, and choose the Tag Selected Objects item in the menu.

To then turn on solar rays, click the Show Solar Rays button, a bit further down in the same panel.

To control the number of rays that are displayed, you can alter the Spacing value.

To change the way the rays are displayed, you need tag either a point, line, or planar object as shown below.