1681-engine / pixel / swayOffset

Function: swayOffset()

function swayOffset(
   tSec, 
   speed, 
   phase, 
   lag, 
   amp, 
   wind, 
   gust, 
   weight, 
   minReach?
): number;

Defined in: src/pixel/swayRig.ts:190

How many whole pixels a strip stands off at tSec: a main swing with a slower second one riding it (so no two trees ever meet in step), leaning a little downwind as the wind rises, scaled by the reach, the wind, the gust and the strip's weight, and rounded — the sway moves in pixel steps, 0 → 1 → 0, never smeared between them.

minReach is the least that reach × wind × gust may come to while any wind blows (a still place's floor, chosen by the game): without it a faint breeze never rounds to a whole pixel and the trees stand dead still, and rounding is the rule, so the floor is what lets the crest of a swing tick one pixel over and back.

Parameters

Parameter	Type	Default value
tSec	number	undefined
speed	number	undefined
phase	number	undefined
lag	number	undefined
amp	number	undefined
wind	number	undefined
gust	number	undefined
weight	number	undefined
minReach	number	0

Returns

number