float rand(float n){return fract(sin(n) * 43758.5453123);}
float noise(float p){
float fl = floor(p);
float fc = fract(p);
return mix(rand(fl), rand(fl + 1.0), fc);
}
All of the below properties or methods, when requested/called in JavaScript, will trigger the browser to synchronously calculate the style and layout*. This is also called reflow or layout thrashing, and is common performance bottleneck.
Generally, all APIs that synchronously provide layout metrics will trigger forced reflow / layout. Read on for additional cases and details.
elem.offsetLeft
,elem.offsetTop
,elem.offsetWidth
,elem.offsetHeight
,elem.offsetParent