paulirish

What forces layout / reflow

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.

Element APIs

Getting box metrics

• elem.offsetLeft, elem.offsetTop, elem.offsetWidth, elem.offsetHeight, elem.offsetParent

0xabad1dea

/* include this file AFTER your standard includes */
/* clang -Weverything -Wno-unused-macros */

/*	SIGNED ARITHMETIC IS THE ENEMY. (use "signed" for main, etc.) */
#define int	BANNED
/*	THESE OTHER THINGS ARE ALSO THE ENEMY. 	*/
#ifdef	strcpy
#undef	strcpy
#endif
#define strcpy	BANNED