What are Dynamic Shadows?
The other day I was confronted by someone complaining that Watch Dogs does not have dynamic shadows. I thought Watch Dogs looked pretty good, why do you need dynamic shadows?
What are dynamic shadows and what do they look like?
11 Answer
Dynamic shadows are shadows that are calculated in real-time to look like the object's real shadow would, based on the shape of the object and the location of the light-source(s).
This is a computationally-expensive task, so it was not feasible in most older 3D games. Instead, they'd precompute shadows for static (non-moving) objects, and emulate shadows for moving objects, typically using a decal painted onto the ground.
Since you mentioned Watch Dogs, here is a comparison of Watch Dogs with and without dynamic shadows (please note this is an unofficial mod, so the shadows look weird sometimes):
