i have a rotating room in my level, and i want to parent some lights to the rotating. If i do this and the room rotates, will the lighting update and move with the source (such as the light texture used in portal:white01)?

edit: also, i want to have a light right behind a big fan and the fan is rotating. will the lighting update and change with that?(im doing it mostly to get a cool look)

The regular light and light_spot entities have lightmaps that are calculated at compile time. I would assume that after the light is calculated they are removed from the map (which explains why they have no parent keyvalue). So when the room rotates the shadows cast onto the walls, ceiling and floor will just rotate as well and not change. I'm not sure if this effect is what you were looking for.

One thing you could try is dynamic lighting from light_dynamic entity. I've heard you have to be careful with it though because it gets very slow very quickly the more lights you put in. And you can also parent light_dynamics. So experiment with these different types of lights.

Also with the fan you will need a light_dynamic for it to keep updating.

Hope this helps!

Yup, you'll need a light_dynamic. Normal lights wont work. I wasnt ever able to get dynamic lights to work for some reason tho.

Instead of parenting the lights, I put the light on something static and lit the room bright enough so that when it rotates, it doesnt look silly.