Instructions: Move the mouse around in the box below in a consistent motion. The difference
between hardware cursor (mouse pointer) and last recorded mouse position (red box) is mouse
input lag. The red circle represents 'two frames' of input lag.
Gray horizontal lines are every 5ms.
blue line: inter-mouse message times (best case is flat line). 8ms is typical for mice/Windows; notebook trackpad is usually around 10ms to 12ms
gray line: mouse move message time offset from rAF time / vsync (best case: consistent sawtooth pattern).
Show hardware cursor
Use rAF time argument
Override event time with now()
Show mouse path
WARNING: It you see a mouse event rate matching your display Hz, the web browser
is likely collapsing several mouse events into one event.