| 33 | static const float CosPhysicalSunSize = std::cos(PhysicalSunSize); |
| 34 | |
| 35 | static float AngleBetween(const Float3& dir0, const Float3& dir1) |
| 36 | { |
| 37 | return std::acos(std::max(Float3::Dot(dir0, dir1), 0.00001f)); |
| 38 | } |
| 39 | |
| 40 | // Returns the result of performing a irradiance integral over the portion |
| 41 | // of the hemisphere covered by a region with angular radius = theta |