Files
react-native-svg/lib/SerializablePath.js
2016-05-04 11:24:13 +08:00

287 lines
8.9 KiB
JavaScript

const MOVE_TO = 0;
const CLOSE = 1;
const LINE_TO = 2;
const CURVE_TO = 3;
const ARC = 4;
export default class SerializablePath {
constructor(path) {
this.reset();
if (path instanceof SerializablePath) {
this.path = path.path.slice();
} else if (path) {
this.push(path);
}
}
/* parser */
push = () => {
let p = Array.prototype.join.call(arguments, ' ')
.replace(/(\.[\d]+)(\-?\.)/ig, '$1,$2') //-.3-.575 => -.3,-.575
.match(/[a-df-z]|[\-+]?(?:[\d\.]e[\-+]?|[^\s\-+,a-z])+/ig);
if (!p) {
return this;
}
let last,
cmd = p[0],
i = 1;
while (cmd){
switch (cmd){
case 'm': this.move(p[i++], p[i++]); break;
case 'l': this.line(p[i++], p[i++]); break;
case 'c': this.curve(p[i++], p[i++], p[i++], p[i++], p[i++], p[i++]); break;
case 's': this.curve(p[i++], p[i++], null, null, p[i++], p[i++]); break;
case 'q': this.curve(p[i++], p[i++], p[i++], p[i++]); break;
case 't': this.curve(p[i++], p[i++]); break;
case 'a': this.arc(p[i + 5], p[i + 6], p[i], p[i + 1], p[i + 3], !+p[i + 4], p[i + 2]); i += 7; break;
case 'h': this.line(p[i++], 0); break;
case 'v': this.line(0, p[i++]); break;
case 'M': this.moveTo(p[i++], p[i++]); break;
case 'L': this.lineTo(p[i++], p[i++]); break;
case 'C': this.curveTo(p[i++], p[i++], p[i++], p[i++], p[i++], p[i++]); break;
case 'S': this.curveTo(p[i++], p[i++], null, null, p[i++], p[i++]); break;
case 'Q': this.curveTo(p[i++], p[i++], p[i++], p[i++]); break;
case 'T': this.curveTo(p[i++], p[i++]); break;
case 'A': this.arcTo(p[i + 5], p[i + 6], p[i], p[i + 1], p[i + 3], !+p[i + 4], p[i + 2]); i += 7; break;
case 'H': this.lineTo(p[i++], this.penY); break;
case 'V': this.lineTo(this.penX, p[i++]); break;
case 'Z': case 'z': this.close(); break;
default: i--; continue;
}
last = cmd;
if (last === 'm') {
last = 'l';
}
else if (last === 'M') {
last = 'L';
}
cmd = p[i++];
}
return this;
};
/* utility methods */
reset = () => {
this.penX = this.penY = 0;
this.penDownX = this.penDownY = null;
this._pivotX = this._pivotY = 0;
this.onReset();
return this;
};
move = (x,y) => {
this.onMove(this.penX, this.penY, this._pivotX = this.penX += (+x), this._pivotY = this.penY += (+y));
return this;
};
moveTo = (x,y) => {
this.onMove(this.penX, this.penY, this._pivotX = this.penX = (+x), this._pivotY = this.penY = (+y));
return this;
};
line = (x,y) => {
return this.lineTo(this.penX + (+x), this.penY + (+y));
};
lineTo = (x,y) => {
if (this.penDownX == null) {
this.penDownX = this.penX; this.penDownY = this.penY;
}
this.onLine(this.penX, this.penY, this._pivotX = this.penX = (+x), this._pivotY = this.penY = (+y));
return this;
};
curve = (c1x, c1y, c2x, c2y, ex, ey) => {
let x = this.penX,
y = this.penY;
return this.curveTo(
x + (+c1x), y + (+c1y),
c2x == null ? null : x + (+c2x),
c2y == null ? null : y + (+c2y),
ex == null ? null : x + (+ex),
ey == null ? null : y + (+ey)
);
};
curveTo = (c1x, c1y, c2x, c2y, ex, ey) => {
let x = this.penX,
y = this.penY;
if (c2x == null){
c2x = +c1x; c2y = +c1y;
c1x = (x * 2) - (this._pivotX || 0); c1y = (y * 2) - (this._pivotY || 0);
}
if (ex == null){
this._pivotX = +c1x; this._pivotY = +c1y;
ex = +c2x; ey = +c2y;
c2x = (ex + (+c1x) * 2) / 3; c2y = (ey + (+c1y) * 2) / 3;
c1x = (x + (+c1x) * 2) / 3; c1y = (y + (+c1y) * 2) / 3;
} else {
this._pivotX = +c2x; this._pivotY = +c2y;
}
if (this.penDownX == null) {
this.penDownX = x; this.penDownY = y;
}
this.onBezierCurve(x, y, +c1x, +c1y, +c2x, +c2y, this.penX = +ex, this.penY = +ey);
return this;
};
arc = (x, y, rx, ry, outer, counterClockwise, rotation) => {
return this.arcTo(this.penX + (+x), this.penY + (+y), rx, ry, outer, counterClockwise, rotation);
};
arcTo = (x, y, rx, ry, outer, counterClockwise, rotation) => {
ry = Math.abs(+ry || +rx || (+y - this.penY));
rx = Math.abs(+rx || (+x - this.penX));
if (!rx || !ry || (x == this.penX && y == this.penY)) {
return this.lineTo(x, y);
}
let tX = this.penX, tY = this.penY, clockwise = !+counterClockwise, large = !!+outer;
let rad = rotation ? rotation * Math.PI / 180 : 0, cos = Math.cos(rad), sin = Math.sin(rad);
x -= tX; y -= tY;
// Ellipse Center
let cx = cos * x / 2 + sin * y / 2,
cy = -sin * x / 2 + cos * y / 2,
rxry = rx * rx * ry * ry,
rycx = ry * ry * cx * cx,
rxcy = rx * rx * cy * cy,
a = rxry - rxcy - rycx;
if (a < 0){
a = Math.sqrt(1 - a / rxry);
rx *= a; ry *= a;
cx = x / 2; cy = y / 2;
} else {
a = Math.sqrt(a / (rxcy + rycx));
if (large == clockwise) a = -a;
let cxd = -a * cy * rx / ry,
cyd = a * cx * ry / rx;
cx = cos * cxd - sin * cyd + x / 2;
cy = sin * cxd + cos * cyd + y / 2;
}
// Rotation + Scale Transform
let xx = cos / rx, yx = sin / rx,
xy = -sin / ry, yy = cos / ry;
// Start and End Angle
let sa = Math.atan2(xy * -cx + yy * -cy, xx * -cx + yx * -cy),
ea = Math.atan2(xy * (x - cx) + yy * (y - cy), xx * (x - cx) + yx * (y - cy));
cx += tX; cy += tY;
x += tX; y += tY;
// Circular Arc
if (this.penDownX == null){ this.penDownX = this.penX; this.penDownY = this.penY; }
this.onArc(
tX, tY, this._pivotX = this.penX = x, this._pivotY = this.penY = y,
cx, cy, rx, ry, sa, ea, !clockwise, rotation
);
return this;
};
counterArc = (x, y, rx, ry, outer) =>{
return this.arc(x, y, rx, ry, outer, true);
};
counterArcTo = (x, y, rx, ry, outer) => {
return this.arcTo(x, y, rx, ry, outer, true);
};
close = () => {
if (this.penDownX != null){
this.onClose(this.penX, this.penY, this.penX = this.penDownX, this.penY = this.penDownY);
this.penDownX = null;
}
return this;
};
/* overridable handlers */
onReset = () => {
this.path = [];
};
onMove = (sx, sy, x, y) => {
this.path.push(MOVE_TO, x, y);
};
onLine = (sx, sy, x, y) => {
this.path.push(LINE_TO, x, y);
};
onBezierCurve = (sx, sy, p1x, p1y, p2x, p2y, x, y) => {
this.path.push(CURVE_TO, p1x, p1y, p2x, p2y, x, y);
};
_arcToBezier = (sx, sy, ex, ey, cx, cy, rx, ry, sa, ea, ccw, rotation) => {
// Inverse Rotation + Scale Transform
let rad = rotation ? rotation * Math.PI / 180 : 0,
cos = Math.cos(rad), sin = Math.sin(rad),
xx = cos * rx, yx = -sin * ry,
xy = sin * rx, yy = cos * ry;
// Bezier Curve Approximation
let arc = ea - sa;
if (arc < 0 && !ccw) {
arc += Math.PI * 2;
} else if (arc > 0 && ccw) {
arc -= Math.PI * 2;
}
let n = Math.ceil(Math.abs(arc / (Math.PI / 2))),
step = arc / n,
k = (4 / 3) * Math.tan(step / 4);
let x = Math.cos(sa), y = Math.sin(sa);
for (let i = 0; i < n; i++){
let cp1x = x - k * y, cp1y = y + k * x;
sa += step;
x = Math.cos(sa); y = Math.sin(sa);
let cp2x = x + k * y, cp2y = y - k * x;
this.onBezierCurve(
sx, sy,
cx + xx * cp1x + yx * cp1y, cy + xy * cp1x + yy * cp1y,
cx + xx * cp2x + yx * cp2y, cy + xy * cp2x + yy * cp2y,
(sx = (cx + xx * x + yx * y)), (sy = (cy + xy * x + yy * y))
);
}
};
onArc = (sx, sy, ex, ey, cx, cy, rx, ry, sa, ea, ccw, rotation) => {
if (rx !== ry || rotation) {
return this._arcToBezier(
sx, sy, ex, ey, cx, cy, rx, ry, sa, ea, ccw, rotation
);
}
this.path.push(ARC, cx, cy, rx, sa, ea, ccw ? 0 : 1);
};
onClose = () => {
this.path.push(CLOSE);
};
toJSON = () => {
return this.path;
};
}