File size: 672 Bytes
bc20498 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 |
var degrees = 180 / Math.PI;
export var identity = {
translateX: 0,
translateY: 0,
rotate: 0,
skewX: 0,
scaleX: 1,
scaleY: 1
};
export default function(a, b, c, d, e, f) {
var scaleX, scaleY, skewX;
if (scaleX = Math.sqrt(a * a + b * b)) a /= scaleX, b /= scaleX;
if (skewX = a * c + b * d) c -= a * skewX, d -= b * skewX;
if (scaleY = Math.sqrt(c * c + d * d)) c /= scaleY, d /= scaleY, skewX /= scaleY;
if (a * d < b * c) a = -a, b = -b, skewX = -skewX, scaleX = -scaleX;
return {
translateX: e,
translateY: f,
rotate: Math.atan2(b, a) * degrees,
skewX: Math.atan(skewX) * degrees,
scaleX: scaleX,
scaleY: scaleY
};
}
|