Old school D3 from simpler times
Dynamic Simplification II
A combination of the map zooming and dynamic simplification demonstrations: as the map zooms in and out, the simplification area threshold is adjusted so that it is always appropriate to the current scale. Thus, the map looks good and renders quickly at all points during the animation.
An additional rendering optimization is that points outside the current viewport are much more heavily simplified that points inside the viewport. This is, in effect, a cheap approximation of viewport clipping.