#jQuery.path
Provides animation along bezier and circular arcs.
The animation engine in jQuery is focussed on single dimensional animation - hence it's difficult to animate two variables along a path.
This simple plugin provides a method of multidimensional animation, and in particular provides a method for animating along bezier curves and arcs.
#Bezier
Example: animate along a bezier path
var bezier_params = {
start: {
x: 185,
y: 185,
angle: 10
},
end: {
x:540,
y:110,
angle: -10,
length: 0.25
}
}
Bezier curves are made form a start point, an end point each with a control point
start is starting point
end is the final point
x,y indicate the coordinates at that point. Required
angle is the angle of the control point from the line joining the start and end. Optional, default is 0
length is the distance from the point to it's control point as a ratio of the distance from start to end. Optional, default is 1/3
#Arc
Exampe: animate along an arc
var arc_params = {
center: [285,185],
radius: 100,
start: 30,
end: 200,
dir: -1
}
center is the coords of the centre of an imaginary circle that contains the start and end point
radius is the radius of this circle
start is the angle of the start point. 0 is "North", measured clockwise
end is the angle of the start point. 0 is "North", measured clockwise
dir is the direction to move in. Only required if not obvious from start and end (e.g. if start is 100, end is 30, but you want to animate clockwise)
#Other Paths
It is trivial to create other paths, or even animate other parameters. E.g:
var SineWave = function() {
this.css = function(p) {
var s = Math.sin(p*20)
var x = 500 - p * 300
var y = s * 50 + 150
var o = ((s+2)/4+0.1)
return {top: y + "px", left: x + "px", opacity: o}
}
};
$("my_elem").animate({path : new SineWave})