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` ````
<svg>
<path id='shape'/>
</svg>
```

` ````
body {
display: flex;
margin: 0;
height: 100vh
}
svg { flex: 1 }
path { cursor: pointer }
```

` ````
const _SVG = document.querySelector('svg'),
_SHAPE = document.getElementById('shape'),
D = 1000 /* viewBox size */,
O = {} /* data object */,
/* number of cubic curves/ polygon vertices */
P = 5,
NF = 50 /* total number of frames for transition */,
TFN = { /* timing functions */
'ease-out': function(k) {
return 1 - Math.pow(1 - k, 1.675)
},
'ease-in-out': function(k) {
return .5*(Math.sin((k - .5)*Math.PI) + 1)
},
'bounce-ini-fin': function(k, s = -.65*Math.PI, e = -s) {
return (Math.sin(k*(e - s) + s) - Math.sin(s))/(Math.sin(e) - Math.sin(s))
}
};
let dir = -1, rID = null, cf = 0, m;
function getStarPoints(f = .5) {
const RCO = f*D /* outer (pentagram) circumradius*/,
BAS = 2*(2*Math.PI/P) /* base angle for star poly */,
BAC = 2*Math.PI/P /* base angle for convex poly */,
RI = RCO*Math.cos(.5*BAS) /*pentagram/ inner pentagon inradius */,
RCI = RI/Math.cos(.5*BAC) /* inner pentagon circumradius */,
ND = 2*P /* total number of distinct points we need to get */,
BAD = 2*Math.PI/ND /* base angle for point distribution */,
PTS = [] /* array we fill with point coordinates */;
for(let i = 0; i < ND; i++) {
let /* radius at end point (inner)/ control point (outer) */
cr = i%2 ? RCI : RCO,
/* angle of radial segment from origin to current point */
ca = i*BAD + .5*Math.PI,
x = Math.round(cr*Math.cos(ca)),
y = Math.round(cr*Math.sin(ca));
PTS.push([x, y]);
/* for even indices double it, control points coincide here */
if(!(i%2)) PTS.push([x, y]);
}
return PTS
};
function getHeartPoints(f = .25) {
const R = f*D /* helper circle radius */,
RC = Math.round(R/Math.SQRT2) /* circumradius of square of edge R */,
XT = 0, YT = -RC /* coords of point T */,
XA = 2*RC, YA = -RC /* coords of A points (x in abs value) */,
XB = 2*RC, YB = RC /* coords of B points (x in abs value) */,
XC = 0, YC = 3*RC /* coords of point C */,
XD = RC, YD = -2*RC /* coords of D points (x in abs value) */,
XE = 3*RC, YE = 0 /* coords of E points (x in abs value) */,
/* const for cubic curve approx of quarter circle */
C = .551915,
CC = 1 - C,
/* coords of ctrl points on TD segs */
XTD = Math.round(CC*XT + C*XD), YTD = Math.round(CC*YT + C*YD),
/* coords of ctrl points on AD segs */
XAD = Math.round(CC*XA + C*XD), YAD = Math.round(CC*YA + C*YD),
/* coords of ctrl points on AE segs */
XAE = Math.round(CC*XA + C*XE), YAE = Math.round(CC*YA + C*YE),
/* coords of ctrl points on BE segs */
XBE = Math.round(CC*XB + C*XE), YBE = Math.round(CC*YB + C*YE);
return [
[XC, YC], [XC, YC], [-XB, YB],
[-XBE, YBE], [-XAE, YAE], [-XA, YA],
[-XAD, YAD], [-XTD, YTD], [XT, YT],
[XTD, YTD], [XAD, YAD], [XA, YA],
[XAE, YAE], [XBE, YBE], [XB, YB]
].map(([x, y]) => [x, y - .09*R]);
};
function fnStr(fname, farg) { return `${fname}(${farg})` };
function range(ini, fin) {
return typeof ini == 'number' ?
fin - ini :
ini.map((c, i) => range(ini[i], fin[i]))
};
function int(ini, rng, tfn, k) {
return typeof ini == 'number' ?
Math.round(ini + (m + dir*tfn(m + dir*k))*rng) :
ini.map((c, i) => int(ini[i], rng[i], tfn, k))
}
function stopAni() {
cancelAnimationFrame(rID);
rID = null;
};
function update() {
cf += dir;
let k = cf/NF;
for(let p in O) {
let co = O[p];
_SHAPE.setAttribute(...[
p,
co.afn(int(co.ini, co.rng, TFN[co.tfn], k))
])
}
if(!(cf%NF)) {
stopAni();
return
}
rID = requestAnimationFrame(update)
};
(function init() {
_SVG.setAttribute('viewBox', [-.5*D, -.5*D, D, D].join(' '));
O.d = {
ini: getStarPoints(),
fin: getHeartPoints(),
afn: function(pts) {
return pts.reduce((a, c, i) => {
return a + (i%3 ? ' ' : 'C') + c
}, `M${pts[pts.length - 1]}`)
},
tfn: 'ease-in-out'
};
O.transform = {
ini: -180,
fin: 0,
afn: (ang) => fnStr('rotate', ang),
tfn: 'bounce-ini-fin'
};
O.fill = {
ini: [255, 215, 0],
fin: [220, 20, 60],
afn: (rgb) => fnStr('rgb', rgb),
tfn: 'ease-out'
};
for(let p in O) {
O[p].rng = range(O[p].ini, O[p].fin);
_SHAPE.setAttribute(p, O[p].afn(O[p].ini));
}
_SHAPE.addEventListener('click', e => {
if(rID) stopAni();
dir *= -1;
m = .5*(1 - dir);
update();
}, false);
})();
```

999px

Also see: Tab Triggers