What's the \phi here? and why do we have a sin(\theta)?

Solved by Surface Integral...

How do you compute this efficiently? Wouldn't you need to shoot rays in all directions from the point to see if anything is blocking the source?

@anonymous https://math.stackexchange.com/questions/188490/why-is-the-differential-solid-angle-have-a-sin-theta-term-in-integration-in-s

What's the \phi here? and why do we have a sin(\theta)?

Solved by Surface Integral...

How do you compute this efficiently? Wouldn't you need to shoot rays in all directions from the point to see if anything is blocking the source?

@anonymous https://math.stackexchange.com/questions/188490/why-is-the-differential-solid-angle-have-a-sin-theta-term-in-integration-in-s