Easings.hx

Easings.hx

package;

class Easings
{
	//Standard easing functions
	public static inline function easeInQuad(t:Float):Float { return t*t }
	public static inline function easeOutQuad(t:Float):Float { return t*(2-t) }
	public static inline function easeInOutQuad(t:Float):Float { return t<.5 ? 2*t*t : -1+(4-2*t)*t }
	public static inline function easeInCubic(t:Float):Float { return t*t*t }
	public static inline function easeOutCubic(t:Float):Float { return (--t)*t*t+1 }
	public static inline function easeInOutCubic(t:Float):Float { return t<.5 ? 4*t*t*t : (t-1)*(2*t-2)*(2*t-2)+1 }
	public static inline function easeInQuart(t:Float):Float { return t*t*t*t }
	public static inline function easeOutQuart(t:Float):Float { return 1-(--t)*t*t*t }
	public static inline function easeInOutQuart(t:Float):Float { return t<.5 ? 8*t*t*t*t : 1-8*(--t)*t*t*t }
	public static inline function easeInQuint(t:Float):Float { return t*t*t*t*t }
	public static inline function easeOutQuint(t:Float):Float { return 1+(--t)*t*t*t*t }
	public static inline function easeInOutQuint(t:Float):Float { return t<.5 ? 16*t*t*t*t*t : 1+16*(--t)*t*t*t*t }

	//1D bezier function.
	public static function bezier(c1:Float, c2:Float, c3:Float, c4:Float, t:Float):Float {
		t = 1 - t;
		function B1(t) { return t*t*t }
		function B2(t) { return 3*t*t*(1-t) }
		function B3(t) { return 3*t*(1-t)*(1-t) }
		function B4(t) { return (1-t)*(1-t)*(1-t) }
		return c1 * B1(t) + c2 * B2(t) + c3 * B3(t) + c4 * B4(t);
	}

	//Makes a function described with 2D bezier curve. See CSS3 `cubic-bezier` and cubic-bezier.com for more details.
	public static inline function makeBezierFunction(c2x, c2y, c3x, c3y):Float->Float
	{
		return BezierEasing.makeBezierEasing(c2x, c2y, c3x, c3y);
	}
}