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SVGPathDataTransformer.ts
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/* eslint @typescript-eslint/no-explicit-any:0 */
// Transform SVG PathData
// http://www.w3.org/TR/SVG/paths.html#PathDataBNF
import {
a2c,
annotateArcCommand,
arcAt,
assertNumbers,
bezierAt,
bezierRoot,
intersectionUnitCircleLine,
} from './mathUtils.js';
import { SVGPathData } from './SVGPathData.js';
import type { SVGCommand, TransformFunction } from './types.js';
// Predefined transforming functions
// Rounds commands values
function ROUND(roundVal = 1e13) {
assertNumbers(roundVal);
function rf(val: number) {
return Math.round(val * roundVal) / roundVal;
}
return function round(command: SVGCommand) {
if ('x1' in command && 'undefined' !== typeof command.x1) {
command.x1 = rf(command.x1);
}
if ('y1' in command && 'undefined' !== typeof command.y1) {
command.y1 = rf(command.y1);
}
if ('x2' in command && 'undefined' !== typeof command.x2) {
command.x2 = rf(command.x2);
}
if ('y2' in command && 'undefined' !== typeof command.y2) {
command.y2 = rf(command.y2);
}
if ('x' in command && 'undefined' !== typeof command.x) {
command.x = rf(command.x);
}
if ('y' in command && 'undefined' !== typeof command.y) {
command.y = rf(command.y);
}
if ('rX' in command && 'undefined' !== typeof command.rX) {
command.rX = rf(command.rX);
}
if ('rY' in command && 'undefined' !== typeof command.rY) {
command.rY = rf(command.rY);
}
return command;
};
}
// Relative to absolute commands
function TO_ABS() {
return INFO((command, prevX, prevY) => {
if (command.relative) {
// x1/y1 values
if ('undefined' !== typeof command.x1) {
command.x1 += prevX;
}
if ('undefined' !== typeof command.y1) {
command.y1 += prevY;
}
// x2/y2 values
if ('undefined' !== typeof command.x2) {
command.x2 += prevX;
}
if ('undefined' !== typeof command.y2) {
command.y2 += prevY;
}
// Finally x/y values
if ('undefined' !== typeof command.x) {
command.x += prevX;
}
if ('undefined' !== typeof command.y) {
command.y += prevY;
}
command.relative = false;
}
return command;
});
}
// Absolute to relative commands
function TO_REL() {
return INFO((command, prevX, prevY) => {
if (!command.relative) {
// x1/y1 values
if ('undefined' !== typeof command.x1) {
command.x1 -= prevX;
}
if ('undefined' !== typeof command.y1) {
command.y1 -= prevY;
}
// x2/y2 values
if ('undefined' !== typeof command.x2) {
command.x2 -= prevX;
}
if ('undefined' !== typeof command.y2) {
command.y2 -= prevY;
}
// Finally x/y values
if ('undefined' !== typeof command.x) {
command.x -= prevX;
}
if ('undefined' !== typeof command.y) {
command.y -= prevY;
}
command.relative = true;
}
return command;
});
}
// Convert H, V, Z and A with rX = 0 to L
function NORMALIZE_HVZ(
normalizeZ = true,
normalizeH = true,
normalizeV = true,
) {
return INFO((command, prevX, prevY, pathStartX, pathStartY) => {
if (isNaN(pathStartX) && !(command.type & SVGPathData.MOVE_TO)) {
throw new Error('path must start with moveto');
}
if (normalizeH && command.type & SVGPathData.HORIZ_LINE_TO) {
command.type = SVGPathData.LINE_TO;
command.y = command.relative ? 0 : prevY;
}
if (normalizeV && command.type & SVGPathData.VERT_LINE_TO) {
command.type = SVGPathData.LINE_TO;
command.x = command.relative ? 0 : prevX;
}
if (normalizeZ && command.type & SVGPathData.CLOSE_PATH) {
command.type = SVGPathData.LINE_TO;
command.x = command.relative ? pathStartX - prevX : pathStartX;
command.y = command.relative ? pathStartY - prevY : pathStartY;
}
if (
command.type & SVGPathData.ARC &&
(0 === command.rX || 0 === command.rY)
) {
command.type = SVGPathData.LINE_TO;
delete command.rX;
delete command.rY;
delete command.xRot;
delete command.lArcFlag;
delete command.sweepFlag;
}
return command;
});
}
/*
* Transforms smooth curves and quads to normal curves and quads (SsTt to CcQq)
*/
function NORMALIZE_ST() {
let prevCurveC2X = NaN;
let prevCurveC2Y = NaN;
let prevQuadCX = NaN;
let prevQuadCY = NaN;
return INFO((command, prevX, prevY) => {
if (command.type & SVGPathData.SMOOTH_CURVE_TO) {
command.type = SVGPathData.CURVE_TO;
prevCurveC2X = isNaN(prevCurveC2X) ? prevX : prevCurveC2X;
prevCurveC2Y = isNaN(prevCurveC2Y) ? prevY : prevCurveC2Y;
command.x1 = command.relative
? prevX - prevCurveC2X
: 2 * prevX - prevCurveC2X;
command.y1 = command.relative
? prevY - prevCurveC2Y
: 2 * prevY - prevCurveC2Y;
}
if (command.type & SVGPathData.CURVE_TO) {
prevCurveC2X = command.relative ? prevX + command.x2 : command.x2;
prevCurveC2Y = command.relative ? prevY + command.y2 : command.y2;
} else {
prevCurveC2X = NaN;
prevCurveC2Y = NaN;
}
if (command.type & SVGPathData.SMOOTH_QUAD_TO) {
command.type = SVGPathData.QUAD_TO;
prevQuadCX = isNaN(prevQuadCX) ? prevX : prevQuadCX;
prevQuadCY = isNaN(prevQuadCY) ? prevY : prevQuadCY;
command.x1 = command.relative
? prevX - prevQuadCX
: 2 * prevX - prevQuadCX;
command.y1 = command.relative
? prevY - prevQuadCY
: 2 * prevY - prevQuadCY;
}
if (command.type & SVGPathData.QUAD_TO) {
prevQuadCX = command.relative ? prevX + command.x1 : command.x1;
prevQuadCY = command.relative ? prevY + command.y1 : command.y1;
} else {
prevQuadCX = NaN;
prevQuadCY = NaN;
}
return command;
});
}
/*
* A quadratic bézier curve can be represented by a cubic bézier curve which has
* the same end points as the quadratic and both control points in place of the
* quadratic"s one.
*
* This transformer replaces QqTt commands with Cc commands respectively.
* This is useful for reading path data into a system which only has a
* representation for cubic curves.
*/
function QT_TO_C() {
let prevQuadX1 = NaN;
let prevQuadY1 = NaN;
return INFO((command, prevX, prevY) => {
if (command.type & SVGPathData.SMOOTH_QUAD_TO) {
command.type = SVGPathData.QUAD_TO;
prevQuadX1 = isNaN(prevQuadX1) ? prevX : prevQuadX1;
prevQuadY1 = isNaN(prevQuadY1) ? prevY : prevQuadY1;
command.x1 = command.relative
? prevX - prevQuadX1
: 2 * prevX - prevQuadX1;
command.y1 = command.relative
? prevY - prevQuadY1
: 2 * prevY - prevQuadY1;
}
if (command.type & SVGPathData.QUAD_TO) {
prevQuadX1 = command.relative ? prevX + command.x1 : command.x1;
prevQuadY1 = command.relative ? prevY + command.y1 : command.y1;
const x1 = command.x1;
const y1 = command.y1;
command.type = SVGPathData.CURVE_TO;
command.x1 = ((command.relative ? 0 : prevX) + x1 * 2) / 3;
command.y1 = ((command.relative ? 0 : prevY) + y1 * 2) / 3;
command.x2 = (command.x + x1 * 2) / 3;
command.y2 = (command.y + y1 * 2) / 3;
} else {
prevQuadX1 = NaN;
prevQuadY1 = NaN;
}
return command;
});
}
function INFO(
f: (
command: any,
prevXAbs: number,
prevYAbs: number,
pathStartXAbs: number,
pathStartYAbs: number,
) => any | any[],
) {
let prevXAbs = 0;
let prevYAbs = 0;
let pathStartXAbs = NaN;
let pathStartYAbs = NaN;
return function transform(command: SVGCommand) {
if (isNaN(pathStartXAbs) && !(command.type & SVGPathData.MOVE_TO)) {
throw new Error('path must start with moveto');
}
const result = f(command, prevXAbs, prevYAbs, pathStartXAbs, pathStartYAbs);
if (command.type & SVGPathData.CLOSE_PATH) {
prevXAbs = pathStartXAbs;
prevYAbs = pathStartYAbs;
}
if ('x' in command && 'undefined' !== typeof command.x) {
prevXAbs = command.relative ? prevXAbs + command.x : command.x;
}
if ('y' in command && 'undefined' !== typeof command.y) {
prevYAbs = command.relative ? prevYAbs + command.y : command.y;
}
if (command.type & SVGPathData.MOVE_TO) {
pathStartXAbs = prevXAbs;
pathStartYAbs = prevYAbs;
}
return result;
};
}
/*
* remove 0-length segments
*/
function SANITIZE(EPS = 0) {
assertNumbers(EPS);
let prevCurveC2X = NaN;
let prevCurveC2Y = NaN;
let prevQuadCX = NaN;
let prevQuadCY = NaN;
return INFO((command, prevX, prevY, pathStartX, pathStartY) => {
const abs = Math.abs;
let skip = false;
let x1Rel = 0;
let y1Rel = 0;
if (command.type & SVGPathData.SMOOTH_CURVE_TO) {
x1Rel = isNaN(prevCurveC2X) ? 0 : prevX - prevCurveC2X;
y1Rel = isNaN(prevCurveC2Y) ? 0 : prevY - prevCurveC2Y;
}
if (command.type & (SVGPathData.CURVE_TO | SVGPathData.SMOOTH_CURVE_TO)) {
prevCurveC2X = command.relative ? prevX + command.x2 : command.x2;
prevCurveC2Y = command.relative ? prevY + command.y2 : command.y2;
} else {
prevCurveC2X = NaN;
prevCurveC2Y = NaN;
}
if (command.type & SVGPathData.SMOOTH_QUAD_TO) {
prevQuadCX = isNaN(prevQuadCX) ? prevX : 2 * prevX - prevQuadCX;
prevQuadCY = isNaN(prevQuadCY) ? prevY : 2 * prevY - prevQuadCY;
} else if (command.type & SVGPathData.QUAD_TO) {
prevQuadCX = command.relative ? prevX + command.x1 : command.x1;
prevQuadCY = command.relative ? prevY + command.y1 : command.y2;
} else {
prevQuadCX = NaN;
prevQuadCY = NaN;
}
if (
command.type & SVGPathData.LINE_COMMANDS ||
(command.type & SVGPathData.ARC &&
(0 === command.rX || 0 === command.rY || !command.lArcFlag)) ||
command.type & SVGPathData.CURVE_TO ||
command.type & SVGPathData.SMOOTH_CURVE_TO ||
command.type & SVGPathData.QUAD_TO ||
command.type & SVGPathData.SMOOTH_QUAD_TO
) {
const xRel =
'undefined' === typeof command.x
? 0
: command.relative
? command.x
: command.x - prevX;
const yRel =
'undefined' === typeof command.y
? 0
: command.relative
? command.y
: command.y - prevY;
x1Rel = !isNaN(prevQuadCX)
? prevQuadCX - prevX
: 'undefined' === typeof command.x1
? x1Rel
: command.relative
? command.x
: command.x1 - prevX;
y1Rel = !isNaN(prevQuadCY)
? prevQuadCY - prevY
: 'undefined' === typeof command.y1
? y1Rel
: command.relative
? command.y
: command.y1 - prevY;
const x2Rel =
'undefined' === typeof command.x2
? 0
: command.relative
? command.x
: command.x2 - prevX;
const y2Rel =
'undefined' === typeof command.y2
? 0
: command.relative
? command.y
: command.y2 - prevY;
if (
abs(xRel) <= EPS &&
abs(yRel) <= EPS &&
abs(x1Rel) <= EPS &&
abs(y1Rel) <= EPS &&
abs(x2Rel) <= EPS &&
abs(y2Rel) <= EPS
) {
skip = true;
}
}
if (command.type & SVGPathData.CLOSE_PATH) {
if (abs(prevX - pathStartX) <= EPS && abs(prevY - pathStartY) <= EPS) {
skip = true;
}
}
return skip ? [] : command;
});
}
// SVG Transforms : http://www.w3.org/TR/SVGTiny12/coords.html#TransformList
// Matrix : http://apike.ca/prog_svg_transform.html
// a c e
// b d f
function MATRIX(
a: number,
b: number,
c: number,
d: number,
e: number,
f: number,
) {
assertNumbers(a, b, c, d, e, f);
return INFO((command, prevX, prevY, pathStartX) => {
const origX1 = command.x1;
const origX2 = command.x2;
// if isNaN(pathStartX), then this is the first command, which is ALWAYS an
// absolute MOVE_TO, regardless what the relative flag says
const comRel = command.relative && !isNaN(pathStartX);
const x = 'undefined' !== typeof command.x ? command.x : comRel ? 0 : prevX;
const y = 'undefined' !== typeof command.y ? command.y : comRel ? 0 : prevY;
if (command.type & SVGPathData.HORIZ_LINE_TO && 0 !== b) {
command.type = SVGPathData.LINE_TO;
command.y = command.relative ? 0 : prevY;
}
if (command.type & SVGPathData.VERT_LINE_TO && 0 !== c) {
command.type = SVGPathData.LINE_TO;
command.x = command.relative ? 0 : prevX;
}
if ('undefined' !== typeof command.x) {
command.x = command.x * a + y * c + (comRel ? 0 : e);
}
if ('undefined' !== typeof command.y) {
command.y = x * b + command.y * d + (comRel ? 0 : f);
}
if ('undefined' !== typeof command.x1) {
command.x1 = command.x1 * a + command.y1 * c + (comRel ? 0 : e);
}
if ('undefined' !== typeof command.y1) {
command.y1 = origX1 * b + command.y1 * d + (comRel ? 0 : f);
}
if ('undefined' !== typeof command.x2) {
command.x2 = command.x2 * a + command.y2 * c + (comRel ? 0 : e);
}
if ('undefined' !== typeof command.y2) {
command.y2 = origX2 * b + command.y2 * d + (comRel ? 0 : f);
}
function sqr(x: number) {
return x * x;
}
const det = a * d - b * c;
if ('undefined' !== typeof command.xRot) {
// Skip if this is a pure translation
if (1 !== a || 0 !== b || 0 !== c || 1 !== d) {
// Special case for singular matrix
if (0 === det) {
// In the singular case, the arc is compressed to a line. The actual geometric image of the original
// curve under this transform possibly extends beyond the starting and/or ending points of the segment, but
// for simplicity we ignore this detail and just replace this command with a single line segment.
delete command.rX;
delete command.rY;
delete command.xRot;
delete command.lArcFlag;
delete command.sweepFlag;
command.type = SVGPathData.LINE_TO;
} else {
// Convert to radians
const xRot = (command.xRot * Math.PI) / 180;
// Convert rotated ellipse to general conic form
// x0^2/rX^2 + y0^2/rY^2 - 1 = 0
// x0 = x*cos(xRot) + y*sin(xRot)
// y0 = -x*sin(xRot) + y*cos(xRot)
// --> A*x^2 + B*x*y + C*y^2 - 1 = 0, where
const sinRot = Math.sin(xRot);
const cosRot = Math.cos(xRot);
const xCurve = 1 / sqr(command.rX);
const yCurve = 1 / sqr(command.rY);
const A = sqr(cosRot) * xCurve + sqr(sinRot) * yCurve;
const B = 2 * sinRot * cosRot * (xCurve - yCurve);
const C = sqr(sinRot) * xCurve + sqr(cosRot) * yCurve;
// Apply matrix to A*x^2 + B*x*y + C*y^2 - 1 = 0
// x1 = a*x + c*y
// y1 = b*x + d*y
// (we can ignore e and f, since pure translations don"t affect the shape of the ellipse)
// --> A1*x1^2 + B1*x1*y1 + C1*y1^2 - det^2 = 0, where
const A1 = A * d * d - B * b * d + C * b * b;
const B1 = B * (a * d + b * c) - 2 * (A * c * d + C * a * b);
const C1 = A * c * c - B * a * c + C * a * a;
// Unapply newXRot to get back to axis-aligned ellipse equation
// x1 = x2*cos(newXRot) - y2*sin(newXRot)
// y1 = x2*sin(newXRot) + y2*cos(newXRot)
// A1*x1^2 + B1*x1*y1 + C1*y1^2 - det^2 =
// x2^2*(A1*cos(newXRot)^2 + B1*sin(newXRot)*cos(newXRot) + C1*sin(newXRot)^2)
// + x2*y2*(2*(C1 - A1)*sin(newXRot)*cos(newXRot) + B1*(cos(newXRot)^2 - sin(newXRot)^2))
// + y2^2*(A1*sin(newXRot)^2 - B1*sin(newXRot)*cos(newXRot) + C1*cos(newXRot)^2)
// (which must have the same zeroes as)
// x2^2/newRX^2 + y2^2/newRY^2 - 1
// (so we have)
// 2*(C1 - A1)*sin(newXRot)*cos(newXRot) + B1*(cos(newXRot)^2 - sin(newXRot)^2) = 0
// (A1 - C1)*sin(2*newXRot) = B1*cos(2*newXRot)
// 2*newXRot = atan2(B1, A1 - C1)
const newXRot = ((Math.atan2(B1, A1 - C1) + Math.PI) % Math.PI) / 2;
// For any integer n, (atan2(B1, A1 - C1) + n*pi)/2 is a solution to the above; incrementing n just swaps
// the x and y radii computed below (since that"s what rotating an ellipse by pi/2 does). Choosing the
// rotation between 0 and pi/2 eliminates the ambiguity and leads to more predictable output.
// Finally, we get newRX and newRY from the same-zeroes relationship that gave us newXRot
const newSinRot = Math.sin(newXRot);
const newCosRot = Math.cos(newXRot);
command.rX =
Math.abs(det) /
Math.sqrt(
A1 * sqr(newCosRot) +
B1 * newSinRot * newCosRot +
C1 * sqr(newSinRot),
);
command.rY =
Math.abs(det) /
Math.sqrt(
A1 * sqr(newSinRot) -
B1 * newSinRot * newCosRot +
C1 * sqr(newCosRot),
);
command.xRot = (newXRot * 180) / Math.PI;
}
}
}
// sweepFlag needs to be inverted when mirroring shapes
// see http://www.itk.ilstu.edu/faculty/javila/SVG/SVG_drawing1/elliptical_curve.htm
// m 65,10 a 50,25 0 1 0 50,25
// M 65,60 A 50,25 0 1 1 115,35
if ('undefined' !== typeof command.sweepFlag && 0 > det) {
command.sweepFlag = +!command.sweepFlag;
}
return command;
});
}
function ROTATE(a: number, x = 0, y = 0) {
assertNumbers(a, x, y);
const sin = Math.sin(a);
const cos = Math.cos(a);
return MATRIX(
cos,
sin,
-sin,
cos,
x - x * cos + y * sin,
y - x * sin - y * cos,
);
}
function TRANSLATE(dX: number, dY = 0) {
assertNumbers(dX, dY);
return MATRIX(1, 0, 0, 1, dX, dY);
}
function SCALE(dX: number, dY = dX) {
assertNumbers(dX, dY);
return MATRIX(dX, 0, 0, dY, 0, 0);
}
function SKEW_X(a: number) {
assertNumbers(a);
return MATRIX(1, 0, Math.atan(a), 1, 0, 0);
}
function SKEW_Y(a: number) {
assertNumbers(a);
return MATRIX(1, Math.atan(a), 0, 1, 0, 0);
}
function X_AXIS_SYMMETRY(xOffset = 0) {
assertNumbers(xOffset);
return MATRIX(-1, 0, 0, 1, xOffset, 0);
}
function Y_AXIS_SYMMETRY(yOffset = 0) {
assertNumbers(yOffset);
return MATRIX(1, 0, 0, -1, 0, yOffset);
}
// Convert arc commands to curve commands
function A_TO_C() {
return INFO((command, prevX, prevY) => {
if (SVGPathData.ARC === command.type) {
return a2c(
command,
command.relative ? 0 : prevX,
command.relative ? 0 : prevY,
);
}
return command;
});
}
// @see annotateArcCommand
function ANNOTATE_ARCS() {
return INFO((c, x1, y1) => {
if (c.relative) {
x1 = 0;
y1 = 0;
}
if (SVGPathData.ARC === c.type) {
annotateArcCommand(c, x1, y1);
}
return c;
});
}
function CLONE<T extends SVGCommand>() {
return (c: T): T => {
return { ...c };
};
}
// @see annotateArcCommand
function CALCULATE_BOUNDS() {
const clone = CLONE();
const toAbs = TO_ABS();
const qtToC = QT_TO_C();
const normST = NORMALIZE_ST();
const f: TransformFunction & {
minX: number;
maxX: number;
minY: number;
maxY: number;
} = INFO((command, prevXAbs, prevYAbs) => {
const c = normST(qtToC(toAbs(clone(command))));
function fixX(absX: number) {
if (absX > f.maxX) {
f.maxX = absX;
}
if (absX < f.minX) {
f.minX = absX;
}
}
function fixY(absY: number) {
if (absY > f.maxY) {
f.maxY = absY;
}
if (absY < f.minY) {
f.minY = absY;
}
}
if (c.type & SVGPathData.DRAWING_COMMANDS) {
fixX(prevXAbs);
fixY(prevYAbs);
}
if (c.type & SVGPathData.HORIZ_LINE_TO) {
fixX(c.x);
}
if (c.type & SVGPathData.VERT_LINE_TO) {
fixY(c.y);
}
if (c.type & SVGPathData.LINE_TO) {
fixX(c.x);
fixY(c.y);
}
if (c.type & SVGPathData.CURVE_TO) {
// add start and end points
fixX(c.x);
fixY(c.y);
const xDerivRoots = bezierRoot(prevXAbs, c.x1, c.x2, c.x);
for (const derivRoot of xDerivRoots) {
if (0 < derivRoot && 1 > derivRoot) {
fixX(bezierAt(prevXAbs, c.x1, c.x2, c.x, derivRoot));
}
}
const yDerivRoots = bezierRoot(prevYAbs, c.y1, c.y2, c.y);
for (const derivRoot of yDerivRoots) {
if (0 < derivRoot && 1 > derivRoot) {
fixY(bezierAt(prevYAbs, c.y1, c.y2, c.y, derivRoot));
}
}
}
if (c.type & SVGPathData.ARC) {
// add start and end points
fixX(c.x);
fixY(c.y);
annotateArcCommand(c, prevXAbs, prevYAbs);
// p = cos(phi) * xv + sin(phi) * yv
// dp = -sin(phi) * xv + cos(phi) * yv = 0
const xRotRad = (c.xRot / 180) * Math.PI;
// points on ellipse for phi = 0° and phi = 90°
const x0 = Math.cos(xRotRad) * c.rX;
const y0 = Math.sin(xRotRad) * c.rX;
const x90 = -Math.sin(xRotRad) * c.rY;
const y90 = Math.cos(xRotRad) * c.rY;
// annotateArcCommand returns phi1 and phi2 such that -180° < phi1 < 180° and phi2 is smaller or greater
// depending on the sweep flag. Calculate phiMin, phiMax such that -180° < phiMin < 180° and phiMin < phiMax
const [phiMin, phiMax] =
c.phi1 < c.phi2
? [c.phi1, c.phi2]
: -180 > c.phi2
? [c.phi2 + 360, c.phi1 + 360]
: [c.phi2, c.phi1];
const normalizeXiEta = ([xi, eta]: [number, number]) => {
const phiRad = Math.atan2(eta, xi);
const phi = (phiRad * 180) / Math.PI;
return phi < phiMin ? phi + 360 : phi;
};
// xi = cos(phi), eta = sin(phi)
const xDerivRoots = intersectionUnitCircleLine(x90, -x0, 0).map(
normalizeXiEta,
);
for (const derivRoot of xDerivRoots) {
if (derivRoot > phiMin && derivRoot < phiMax) {
fixX(arcAt(c.cX, x0, x90, derivRoot));
}
}
const yDerivRoots = intersectionUnitCircleLine(y90, -y0, 0).map(
normalizeXiEta,
);
for (const derivRoot of yDerivRoots) {
if (derivRoot > phiMin && derivRoot < phiMax) {
fixY(arcAt(c.cY, y0, y90, derivRoot));
}
}
}
return command;
}) as any;
f.minX = Infinity;
f.maxX = -Infinity;
f.minY = Infinity;
f.maxY = -Infinity;
return f;
}
export const SVGPathDataTransformer = {
ROUND,
TO_ABS,
TO_REL,
NORMALIZE_HVZ,
NORMALIZE_ST,
QT_TO_C,
INFO,
SANITIZE,
MATRIX,
ROTATE,
TRANSLATE,
SCALE,
SKEW_X,
SKEW_Y,
X_AXIS_SYMMETRY,
Y_AXIS_SYMMETRY,
A_TO_C,
ANNOTATE_ARCS,
CLONE,
CALCULATE_BOUNDS,
};