pdf-lib
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Create and modify PDF files with JavaScript
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JavaScript
// Originated from pdfkit Copyright (c) 2014 Devon Govett
// https://github.com/foliojs/pdfkit/blob/1e62e6ffe24b378eb890df507a47610f4c4a7b24/lib/path.js
// MIT LICENSE
// Updated for pdf-lib & TypeScript by Jeremy Messenger
import { appendBezierCurve, appendQuadraticCurve, closePath, lineTo, moveTo, } from "./operators";
var cx = 0;
var cy = 0;
var px = 0;
var py = 0;
var sx = 0;
var sy = 0;
var parameters = new Map([
['A', 7],
['a', 7],
['C', 6],
['c', 6],
['H', 1],
['h', 1],
['L', 2],
['l', 2],
['M', 2],
['m', 2],
['Q', 4],
['q', 4],
['S', 4],
['s', 4],
['T', 2],
['t', 2],
['V', 1],
['v', 1],
['Z', 0],
['z', 0],
]);
var parse = function (path) {
var cmd;
var ret = [];
var args = [];
var curArg = '';
var foundDecimal = false;
var params = 0;
for (var _i = 0, path_1 = path; _i < path_1.length; _i++) {
var c = path_1[_i];
if (parameters.has(c)) {
params = parameters.get(c);
if (cmd) {
// save existing command
if (curArg.length > 0) {
args[args.length] = +curArg;
}
ret[ret.length] = { cmd: cmd, args: args };
args = [];
curArg = '';
foundDecimal = false;
}
cmd = c;
}
else if ([' ', ','].includes(c) ||
(c === '-' && curArg.length > 0 && curArg[curArg.length - 1] !== 'e') ||
(c === '.' && foundDecimal)) {
if (curArg.length === 0) {
continue;
}
if (args.length === params) {
// handle reused commands
ret[ret.length] = { cmd: cmd, args: args };
args = [+curArg];
// handle assumed commands
if (cmd === 'M') {
cmd = 'L';
}
if (cmd === 'm') {
cmd = 'l';
}
}
else {
args[args.length] = +curArg;
}
foundDecimal = c === '.';
// fix for negative numbers or repeated decimals with no delimeter between commands
curArg = ['-', '.'].includes(c) ? c : '';
}
else {
curArg += c;
if (c === '.') {
foundDecimal = true;
}
}
}
// add the last command
if (curArg.length > 0) {
if (args.length === params) {
// handle reused commands
ret[ret.length] = { cmd: cmd, args: args };
args = [+curArg];
// handle assumed commands
if (cmd === 'M') {
cmd = 'L';
}
if (cmd === 'm') {
cmd = 'l';
}
}
else {
args[args.length] = +curArg;
}
}
ret[ret.length] = { cmd: cmd, args: args };
return ret;
};
var apply = function (commands) {
// current point, control point, and subpath starting point
cx = cy = px = py = sx = sy = 0;
// run the commands
var cmds = [];
for (var i = 0; i < commands.length; i++) {
var c = commands[i];
if (c.cmd && typeof runners[c.cmd] === 'function') {
var cmd = runners[c.cmd](c.args);
if (Array.isArray(cmd)) {
cmds = cmds.concat(cmd);
}
else {
cmds.push(cmd);
}
}
}
return cmds;
};
var runners = {
M: function (a) {
cx = a[0];
cy = a[1];
px = py = null;
sx = cx;
sy = cy;
return moveTo(cx, cy);
},
m: function (a) {
cx += a[0];
cy += a[1];
px = py = null;
sx = cx;
sy = cy;
return moveTo(cx, cy);
},
C: function (a) {
cx = a[4];
cy = a[5];
px = a[2];
py = a[3];
return appendBezierCurve(a[0], a[1], a[2], a[3], a[4], a[5]);
},
c: function (a) {
var cmd = appendBezierCurve(a[0] + cx, a[1] + cy, a[2] + cx, a[3] + cy, a[4] + cx, a[5] + cy);
px = cx + a[2];
py = cy + a[3];
cx += a[4];
cy += a[5];
return cmd;
},
S: function (a) {
if (px === null || py === null) {
px = cx;
py = cy;
}
var cmd = appendBezierCurve(cx - (px - cx), cy - (py - cy), a[0], a[1], a[2], a[3]);
px = a[0];
py = a[1];
cx = a[2];
cy = a[3];
return cmd;
},
s: function (a) {
if (px === null || py === null) {
px = cx;
py = cy;
}
var cmd = appendBezierCurve(cx - (px - cx), cy - (py - cy), cx + a[0], cy + a[1], cx + a[2], cy + a[3]);
px = cx + a[0];
py = cy + a[1];
cx += a[2];
cy += a[3];
return cmd;
},
Q: function (a) {
px = a[0];
py = a[1];
cx = a[2];
cy = a[3];
return appendQuadraticCurve(a[0], a[1], cx, cy);
},
q: function (a) {
var cmd = appendQuadraticCurve(a[0] + cx, a[1] + cy, a[2] + cx, a[3] + cy);
px = cx + a[0];
py = cy + a[1];
cx += a[2];
cy += a[3];
return cmd;
},
T: function (a) {
if (px === null || py === null) {
px = cx;
py = cy;
}
else {
px = cx - (px - cx);
py = cy - (py - cy);
}
var cmd = appendQuadraticCurve(px, py, a[0], a[1]);
px = cx - (px - cx);
py = cy - (py - cy);
cx = a[0];
cy = a[1];
return cmd;
},
t: function (a) {
if (px === null || py === null) {
px = cx;
py = cy;
}
else {
px = cx - (px - cx);
py = cy - (py - cy);
}
var cmd = appendQuadraticCurve(px, py, cx + a[0], cy + a[1]);
cx += a[0];
cy += a[1];
return cmd;
},
A: function (a) {
var cmds = solveArc(cx, cy, a);
cx = a[5];
cy = a[6];
return cmds;
},
a: function (a) {
a[5] += cx;
a[6] += cy;
var cmds = solveArc(cx, cy, a);
cx = a[5];
cy = a[6];
return cmds;
},
L: function (a) {
cx = a[0];
cy = a[1];
px = py = null;
return lineTo(cx, cy);
},
l: function (a) {
cx += a[0];
cy += a[1];
px = py = null;
return lineTo(cx, cy);
},
H: function (a) {
cx = a[0];
px = py = null;
return lineTo(cx, cy);
},
h: function (a) {
cx += a[0];
px = py = null;
return lineTo(cx, cy);
},
V: function (a) {
cy = a[0];
px = py = null;
return lineTo(cx, cy);
},
v: function (a) {
cy += a[0];
px = py = null;
return lineTo(cx, cy);
},
Z: function () {
var cmd = closePath();
cx = sx;
cy = sy;
return cmd;
},
z: function () {
var cmd = closePath();
cx = sx;
cy = sy;
return cmd;
},
};
var solveArc = function (x, y, coords) {
var rx = coords[0], ry = coords[1], rot = coords[2], large = coords[3], sweep = coords[4], ex = coords[5], ey = coords[6];
var segs = arcToSegments(ex, ey, rx, ry, large, sweep, rot, x, y);
var cmds = [];
for (var _i = 0, segs_1 = segs; _i < segs_1.length; _i++) {
var seg = segs_1[_i];
var bez = segmentToBezier.apply(void 0, seg);
cmds.push(appendBezierCurve.apply(void 0, bez));
}
return cmds;
};
// from Inkscape svgtopdf, thanks!
var arcToSegments = function (x, y, rx, ry, large, sweep, rotateX, ox, oy) {
var th = rotateX * (Math.PI / 180);
var sinTh = Math.sin(th);
var cosTh = Math.cos(th);
rx = Math.abs(rx);
ry = Math.abs(ry);
px = cosTh * (ox - x) * 0.5 + sinTh * (oy - y) * 0.5;
py = cosTh * (oy - y) * 0.5 - sinTh * (ox - x) * 0.5;
var pl = (px * px) / (rx * rx) + (py * py) / (ry * ry);
if (pl > 1) {
pl = Math.sqrt(pl);
rx *= pl;
ry *= pl;
}
var a00 = cosTh / rx;
var a01 = sinTh / rx;
var a10 = -sinTh / ry;
var a11 = cosTh / ry;
var x0 = a00 * ox + a01 * oy;
var y0 = a10 * ox + a11 * oy;
var x1 = a00 * x + a01 * y;
var y1 = a10 * x + a11 * y;
var d = (x1 - x0) * (x1 - x0) + (y1 - y0) * (y1 - y0);
var sfactorSq = 1 / d - 0.25;
if (sfactorSq < 0) {
sfactorSq = 0;
}
var sfactor = Math.sqrt(sfactorSq);
if (sweep === large) {
sfactor = -sfactor;
}
var xc = 0.5 * (x0 + x1) - sfactor * (y1 - y0);
var yc = 0.5 * (y0 + y1) + sfactor * (x1 - x0);
var th0 = Math.atan2(y0 - yc, x0 - xc);
var th1 = Math.atan2(y1 - yc, x1 - xc);
var thArc = th1 - th0;
if (thArc < 0 && sweep === 1) {
thArc += 2 * Math.PI;
}
else if (thArc > 0 && sweep === 0) {
thArc -= 2 * Math.PI;
}
var segments = Math.ceil(Math.abs(thArc / (Math.PI * 0.5 + 0.001)));
var result = [];
for (var i = 0; i < segments; i++) {
var th2 = th0 + (i * thArc) / segments;
var th3 = th0 + ((i + 1) * thArc) / segments;
result[i] = [xc, yc, th2, th3, rx, ry, sinTh, cosTh];
}
return result;
};
var segmentToBezier = function (cx1, cy1, th0, th1, rx, ry, sinTh, cosTh) {
var a00 = cosTh * rx;
var a01 = -sinTh * ry;
var a10 = sinTh * rx;
var a11 = cosTh * ry;
var thHalf = 0.5 * (th1 - th0);
var t = ((8 / 3) * Math.sin(thHalf * 0.5) * Math.sin(thHalf * 0.5)) /
Math.sin(thHalf);
var x1 = cx1 + Math.cos(th0) - t * Math.sin(th0);
var y1 = cy1 + Math.sin(th0) + t * Math.cos(th0);
var x3 = cx1 + Math.cos(th1);
var y3 = cy1 + Math.sin(th1);
var x2 = x3 + t * Math.sin(th1);
var y2 = y3 - t * Math.cos(th1);
var result = [
a00 * x1 + a01 * y1,
a10 * x1 + a11 * y1,
a00 * x2 + a01 * y2,
a10 * x2 + a11 * y2,
a00 * x3 + a01 * y3,
a10 * x3 + a11 * y3,
];
return result;
};
export var svgPathToOperators = function (path) { return apply(parse(path)); };
//# sourceMappingURL=svgPath.js.map