The waves are partly real and partly me.

LA genuinely built in bursts. The 1920s and the postwar decade each account for over 230,000 buildings still standing, and the 1930s and 1970s onward are much thinner, so even a perfect per-year animation would surge and pause.

But really it's for performance -- I group buildings into 5-year bins and fade each bin in over its span, rather than popping each building at its exact year.

A per-year filter on a million polygons re-tessellates every visible tile, which was too slow to animate, whereas fading pre-built layers is reasonably fast.

Glad you found your house!