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@malipetek
Last active March 26, 2019 12:43
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Fix By Ikaros
function transformSVGPath(pathStr) {
const DIGIT_0 = 48, DIGIT_9 = 57, COMMA = 44, SPACE = 32, PERIOD = 46,
MINUS = 45;
const DEGS_TO_RADS = Math.PI/180.0;
var path = new THREE.Shape();
var idx = 1, len = pathStr.length, activeCmd,
x = 0, y = 0, nx = 0, ny = 0, firstX = null, firstY = null,
x1 = 0, x2 = 0, y1 = 0, y2 = 0,
rx = 0, ry = 0, xar = 0, laf = 0, sf = 0, cx, cy;
function eatNum() {
var sidx, c, isFloat = false, s;
// eat delims
while (idx < len) {
c = pathStr.charCodeAt(idx);
if (c !== COMMA && c !== SPACE)
break;
idx++;
}
if (c === MINUS)
sidx = idx++;
else
sidx = idx;
// eat number
while (idx < len) {
c = pathStr.charCodeAt(idx);
if (DIGIT_0 <= c && c <= DIGIT_9) {
idx++;
continue;
}
else if (c === PERIOD) {
idx++;
isFloat = true;
continue;
}
s = pathStr.substring(sidx, idx);
return isFloat ? parseFloat(s) : parseInt(s);
}
s = pathStr.substring(sidx);
return isFloat ? parseFloat(s) : parseInt(s);
}
function nextIsNum() {
var c;
// do permanently eat any delims...
while (idx < len) {
c = pathStr.charCodeAt(idx);
if (c !== COMMA && c !== SPACE)
break;
idx++;
}
c = pathStr.charCodeAt(idx);
return (c === MINUS || (DIGIT_0 <= c && c <= DIGIT_9));
}
function eatAbsoluteArc() {
rx = eatNum();
ry = eatNum();
xar = eatNum() * DEGS_TO_RADS;
laf = eatNum();
sf = eatNum();
nx = eatNum();
ny = eatNum();
if( activeCmd == 'a' ) { // relative
nx += x;
ny += y;
}
console.debug( "[SVGPath2ThreeShape.eatAbsoluteArc] Read arc params: rx=" + rx + ", ry=" + ry + ", xar=" + xar + ", laf=" + laf + ", sf=" + sf + ", nx=" + nx + ", ny=" + ny );
if (rx !== ry) {
console.warn("Forcing elliptical arc to be a circular one :(",
rx, ry);
}
// SVG implementation notes does all the math for us! woo!
// http://www.w3.org/TR/SVG/implnote.html#ArcImplementationNotes
// step1, using x1 as x1'
x1 = Math.cos(xar) * (x - nx) / 2 + Math.sin(xar) * (y - ny) / 2;
y1 = -Math.sin(xar) * (x - nx) / 2 + Math.cos(xar) * (y - ny) / 2;
// step 2, using x2 as cx'
console.debug( "[SVGPath2ThreeShape.eatAbsoluteArc] TMP x1=" + x1 + ", y1=" + y1 + ", (rx*rx * y1*y1 + ry*ry * x1*x1)=" + (rx*rx * y1*y1 + ry*ry * x1*x1) + ", (rx*rx * ry*ry - rx*rx * y1*y1 - ry*ry * x1*x1)=" + (rx*rx * ry*ry - rx*rx * y1*y1 - ry*ry * x1*x1) );
var norm = Math.sqrt( Math.abs(
(rx*rx * ry*ry - rx*rx * y1*y1 - ry*ry * x1*x1) /
(rx*rx * y1*y1 + ry*ry * x1*x1) ) );
if (laf === sf)
norm = -norm;
x2 = norm * rx * y1 / ry;
y2 = norm * -ry * x1 / rx;
console.debug( "[SVGPath2ThreeShape.eatAbsoluteArc] TMP norm=" + norm + ", x2=" + x2 + ", y2=" + y2 );
// step 3
cx = Math.cos(xar) * x2 - Math.sin(xar) * y2 + (x + nx) / 2;
cy = Math.sin(xar) * x2 + Math.cos(xar) * y2 + (y + ny) / 2;
console.debug( "[SVGPath2ThreeShape.eatAbsoluteArc] TMP cx=" + cx + ", cy=" + cy );
var u = new THREE.Vector2(1, 0),
v = new THREE.Vector2((x1 - x2) / rx,
(y1 - y2) / ry);
var startAng = Math.acos(u.dot(v) / u.length() / v.length());
if (u.x * v.y - u.y * v.x < 0)
startAng = -startAng;
// we can reuse 'v' from start angle as our 'u' for delta angle
u.x = (-x1 - x2) / rx;
u.y = (-y1 - y2) / ry;
var deltaAng = Math.acos(v.dot(u) / v.length() / u.length());
// This normalization ends up making our curves fail to triangulate...
if (v.x * u.y - v.y * u.x < 0)
deltaAng = -deltaAng;
if (!sf && deltaAng > 0)
deltaAng -= Math.PI * 2;
if (sf && deltaAng < 0)
deltaAng += Math.PI * 2;
console.debug( "[SVGPath2ThreeShape.eatAbsoluteArc] Building arc from values: cx=" + cx + ", cy=" + cy + ", startAng=" + startAng + ", deltaAng=" + deltaAng + ", endAng=" + (startAng+deltaAng) + ", sweepFlag=" + sf );
path.absarc(cx, cy, rx, startAng, startAng + deltaAng, sf);
x = nx;
y = ny;
}
var canRepeat;
activeCmd = pathStr[0];
while (idx <= len) {
canRepeat = true;
switch (activeCmd) {
// moveto commands, become lineto's if repeated
case 'M':
x = eatNum();
y = eatNum();
path.moveTo(x, y);
activeCmd = 'L';
break;
case 'm':
x += eatNum();
y += eatNum();
path.moveTo(x, y);
activeCmd = 'l';
break;
case 'Z':
case 'z':
canRepeat = false;
if (x !== firstX || y !== firstY)
path.lineTo(firstX, firstY);
break;
// - lines!
case 'L':
case 'H':
case 'V':
nx = (activeCmd === 'V') ? x : eatNum();
ny = (activeCmd === 'H') ? y : eatNum();
path.lineTo(nx, ny);
x = nx;
y = ny;
break;
case 'l':
case 'h':
case 'v':
nx = (activeCmd === 'v') ? x : (x + eatNum());
ny = (activeCmd === 'h') ? y : (y + eatNum());
path.lineTo(nx, ny);
x = nx;
y = ny;
break;
// - cubic bezier
case 'C':
x1 = eatNum(); y1 = eatNum();
case 'S':
if (activeCmd === 'S') {
x1 = 2 * x - x2; y1 = 2 * y - y2;
}
x2 = eatNum();
y2 = eatNum();
nx = eatNum();
ny = eatNum();
path.bezierCurveTo(x1, y1, x2, y2, nx, ny);
x = nx; y = ny;
break;
case 'c':
x1 = x + eatNum();
y1 = y + eatNum();
case 's':
if (activeCmd === 's') {
x1 = 2 * x - x2;
y1 = 2 * y - y2;
}
x2 = x + eatNum();
y2 = y + eatNum();
nx = x + eatNum();
ny = y + eatNum();
path.bezierCurveTo(x1, y1, x2, y2, nx, ny);
x = nx; y = ny;
break;
// - quadratic bezier
case 'Q':
x1 = eatNum(); y1 = eatNum();
case 'T':
if (activeCmd === 'T') {
x1 = 2 * x - x1;
y1 = 2 * y - y1;
}
nx = eatNum();
ny = eatNum();
path.quadraticCurveTo(x1, y1, nx, ny);
x = nx;
y = ny;
break;
case 'q':
x1 = x + eatNum();
y1 = y + eatNum();
case 't':
if (activeCmd === 't') {
x1 = 2 * x - x1;
y1 = 2 * y - y1;
}
nx = x + eatNum();
ny = y + eatNum();
path.quadraticCurveTo(x1, y1, nx, ny);
x = nx; y = ny;
break;
// - elliptical arc
case 'A':
// eatAbsoluteArc();
case 'a':
eatAbsoluteArc();
break;
default:
throw new Error("weird path command: " + activeCmd);
}
if (firstX === null) {
firstX = x;
firstY = y;
}
// just reissue the command
if (canRepeat && nextIsNum())
continue;
activeCmd = pathStr[idx++];
}
return path;
}
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