Screen blending is quite trivial to implement and very useful to have.
Additive can be very aggressive, quickly overblowing colors above the 1.0 threshold.
Screen behaves like an inverted multiply, which is much softer.
You basically use Screen rather than Add, for the same reason you use Multiply rather than Subtract.
Here’s the math:
Screen(Src, Dst) = 1-(1-Src) * (1-Dst)Here’s how it looks:
