dxf
Version:
DXF parser for node/browser
286 lines (275 loc) • 11.4 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.polyfaceOutline = exports.interpolateBSpline = exports["default"] = void 0;
var _bSpline = _interopRequireDefault(require("./util/bSpline"));
var _logger = _interopRequireDefault(require("./util/logger"));
var _createArcForLWPolyline = _interopRequireDefault(require("./util/createArcForLWPolyline"));
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { "default": obj }; }
function _toConsumableArray(arr) { return _arrayWithoutHoles(arr) || _iterableToArray(arr) || _unsupportedIterableToArray(arr) || _nonIterableSpread(); }
function _nonIterableSpread() { throw new TypeError("Invalid attempt to spread non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); }
function _iterableToArray(iter) { if (typeof Symbol !== "undefined" && iter[Symbol.iterator] != null || iter["@@iterator"] != null) return Array.from(iter); }
function _arrayWithoutHoles(arr) { if (Array.isArray(arr)) return _arrayLikeToArray(arr); }
function _createForOfIteratorHelper(o, allowArrayLike) { var it = typeof Symbol !== "undefined" && o[Symbol.iterator] || o["@@iterator"]; if (!it) { if (Array.isArray(o) || (it = _unsupportedIterableToArray(o)) || allowArrayLike && o && typeof o.length === "number") { if (it) o = it; var i = 0; var F = function F() {}; return { s: F, n: function n() { if (i >= o.length) return { done: true }; return { done: false, value: o[i++] }; }, e: function e(_e) { throw _e; }, f: F }; } throw new TypeError("Invalid attempt to iterate non-iterable instance.\nIn order to be iterable, non-array objects must have a [Symbol.iterator]() method."); } var normalCompletion = true, didErr = false, err; return { s: function s() { it = it.call(o); }, n: function n() { var step = it.next(); normalCompletion = step.done; return step; }, e: function e(_e2) { didErr = true; err = _e2; }, f: function f() { try { if (!normalCompletion && it["return"] != null) it["return"](); } finally { if (didErr) throw err; } } }; }
function _unsupportedIterableToArray(o, minLen) { if (!o) return; if (typeof o === "string") return _arrayLikeToArray(o, minLen); var n = Object.prototype.toString.call(o).slice(8, -1); if (n === "Object" && o.constructor) n = o.constructor.name; if (n === "Map" || n === "Set") return Array.from(o); if (n === "Arguments" || /^(?:Ui|I)nt(?:8|16|32)(?:Clamped)?Array$/.test(n)) return _arrayLikeToArray(o, minLen); }
function _arrayLikeToArray(arr, len) { if (len == null || len > arr.length) len = arr.length; for (var i = 0, arr2 = new Array(len); i < len; i++) arr2[i] = arr[i]; return arr2; }
/**
* Rotate a set of points.
*
* @param points the points
* @param angle the rotation angle
*/
var rotate = function rotate(points, angle) {
return points.map(function (p) {
return [p[0] * Math.cos(angle) - p[1] * Math.sin(angle), p[1] * Math.cos(angle) + p[0] * Math.sin(angle)];
});
};
/**
* Interpolate an ellipse
* @param cx center X
* @param cy center Y
* @param rx radius X
* @param ry radius Y
* @param start start angle in radians
* @param start end angle in radians
*/
var interpolateEllipse = function interpolateEllipse(cx, cy, rx, ry, start, end, rotationAngle) {
if (end < start) {
end += Math.PI * 2;
}
// ----- Relative points -----
// Start point
var points = [];
var dTheta = Math.PI * 2 / 72;
var EPS = 1e-6;
for (var theta = start; theta < end - EPS; theta += dTheta) {
points.push([Math.cos(theta) * rx, Math.sin(theta) * ry]);
}
points.push([Math.cos(end) * rx, Math.sin(end) * ry]);
// ----- Rotate -----
if (rotationAngle) {
points = rotate(points, rotationAngle);
}
// ----- Offset center -----
points = points.map(function (p) {
return [cx + p[0], cy + p[1]];
});
return points;
};
/**
* Interpolate a b-spline. The algorithm examins the knot vector
* to create segments for interpolation. The parameterisation value
* is re-normalised back to [0,1] as that is what the lib expects (
* and t i de-normalised in the b-spline library)
*
* @param controlPoints the control points
* @param degree the b-spline degree
* @param knots the knot vector
* @returns the polyline
*/
var interpolateBSpline = function interpolateBSpline(controlPoints, degree, knots, interpolationsPerSplineSegment, weights) {
var polyline = [];
var controlPointsForLib = controlPoints.map(function (p) {
return [p.x, p.y];
});
var segmentTs = [knots[degree]];
var domain = [knots[degree], knots[knots.length - 1 - degree]];
for (var k = degree + 1; k < knots.length - degree; ++k) {
if (segmentTs[segmentTs.length - 1] !== knots[k]) {
segmentTs.push(knots[k]);
}
}
interpolationsPerSplineSegment = interpolationsPerSplineSegment || 25;
for (var i = 1; i < segmentTs.length; ++i) {
var uMin = segmentTs[i - 1];
var uMax = segmentTs[i];
for (var _k = 0; _k <= interpolationsPerSplineSegment; ++_k) {
var u = _k / interpolationsPerSplineSegment * (uMax - uMin) + uMin;
// Clamp t to 0, 1 to handle numerical precision issues
var t = (u - domain[0]) / (domain[1] - domain[0]);
t = Math.max(t, 0);
t = Math.min(t, 1);
var p = (0, _bSpline["default"])(t, degree, controlPointsForLib, knots, weights);
polyline.push(p);
}
}
return polyline;
};
exports.interpolateBSpline = interpolateBSpline;
var polyfaceOutline = function polyfaceOutline(entity) {
var vertices = [];
var faces = [];
var _iterator = _createForOfIteratorHelper(entity.vertices),
_step;
try {
for (_iterator.s(); !(_step = _iterator.n()).done;) {
var v = _step.value;
if (v.faces) {
var _face = {
indices: [],
hiddens: []
};
var _iterator3 = _createForOfIteratorHelper(v.faces),
_step3;
try {
for (_iterator3.s(); !(_step3 = _iterator3.n()).done;) {
var i = _step3.value;
if (i === 0) {
break;
}
// Negative indices signify hidden edges
_face.indices.push(i < 0 ? -i - 1 : i - 1);
_face.hiddens.push(i < 0);
}
} catch (err) {
_iterator3.e(err);
} finally {
_iterator3.f();
}
if ([3, 4].includes(_face.indices.length)) faces.push(_face);
} else {
vertices.push({
x: v.x,
y: v.y
});
}
}
// If a segment starts at the end of a previous line, continue it
} catch (err) {
_iterator.e(err);
} finally {
_iterator.f();
}
var polylines = [];
var segment = function segment(a, b) {
for (var _i = 0, _polylines = polylines; _i < _polylines.length; _i++) {
var prev = _polylines[_i];
if (prev.slice(-1)[0] === a) {
return prev.push(b);
}
}
polylines.push([a, b]);
};
for (var _i2 = 0, _faces = faces; _i2 < _faces.length; _i2++) {
var face = _faces[_i2];
for (var beg = 0; beg < face.indices.length; beg++) {
if (face.hiddens[beg]) {
continue;
}
var end = (beg + 1) % face.indices.length;
segment(face.indices[beg], face.indices[end]);
}
}
// Sometimes segments are not sequential, in that case
// we need to find if they can mend gaps between others
for (var _i3 = 0, _polylines2 = polylines; _i3 < _polylines2.length; _i3++) {
var a = _polylines2[_i3];
var _iterator2 = _createForOfIteratorHelper(polylines),
_step2;
try {
for (_iterator2.s(); !(_step2 = _iterator2.n()).done;) {
var b = _step2.value;
if (a !== b && a[0] === b.slice(-1)[0]) {
b.push.apply(b, _toConsumableArray(a.slice(1)));
a.splice(0, a.length);
break;
}
}
} catch (err) {
_iterator2.e(err);
} finally {
_iterator2.f();
}
}
return polylines.filter(function (l) {
return l.length;
}).map(function (l) {
return l.map(function (i) {
return vertices[i];
}).map(function (v) {
return [v.x, v.y];
});
});
};
/**
* Convert a parsed DXF entity to a polyline. These can be used to render the
* the DXF in SVG, Canvas, WebGL etc., without depending on native support
* of primitive objects (ellispe, spline etc.)
*/
exports.polyfaceOutline = polyfaceOutline;
var _default = function _default(entity, options) {
options = options || {};
var polyline;
if (entity.type === 'LINE') {
polyline = [[entity.start.x, entity.start.y], [entity.end.x, entity.end.y]];
}
if (entity.type === 'LWPOLYLINE' || entity.type === 'POLYLINE') {
polyline = [];
if (entity.polyfaceMesh) {
var _polyline;
// Only return the first polyline because we can't return many
(_polyline = polyline).push.apply(_polyline, _toConsumableArray(polyfaceOutline(entity)[0]));
} else if (entity.polygonMesh) {
// Do not attempt to render polygon meshes
} else if (entity.vertices.length) {
if (entity.closed) {
entity.vertices = entity.vertices.concat(entity.vertices[0]);
}
for (var i = 0, il = entity.vertices.length; i < il - 1; ++i) {
var from = [entity.vertices[i].x, entity.vertices[i].y];
var to = [entity.vertices[i + 1].x, entity.vertices[i + 1].y];
polyline.push(from);
if (entity.vertices[i].bulge) {
polyline = polyline.concat((0, _createArcForLWPolyline["default"])(from, to, entity.vertices[i].bulge));
}
// The last iteration of the for loop
if (i === il - 2) {
polyline.push(to);
}
}
} else {
_logger["default"].warn('Polyline entity with no vertices');
}
}
if (entity.type === 'CIRCLE') {
polyline = interpolateEllipse(entity.x, entity.y, entity.r, entity.r, 0, Math.PI * 2);
if (entity.extrusionZ === -1) {
polyline = polyline.map(function (p) {
return [-p[0], p[1]];
});
}
}
if (entity.type === 'ELLIPSE') {
var rx = Math.sqrt(entity.majorX * entity.majorX + entity.majorY * entity.majorY);
var ry = entity.axisRatio * rx;
var majorAxisRotation = -Math.atan2(-entity.majorY, entity.majorX);
polyline = interpolateEllipse(entity.x, entity.y, rx, ry, entity.startAngle, entity.endAngle, majorAxisRotation);
if (entity.extrusionZ === -1) {
polyline = polyline.map(function (p) {
return [-p[0], p[1]];
});
}
}
if (entity.type === 'ARC') {
// Why on earth DXF has degree start & end angles for arc,
// and radian start & end angles for ellipses is a mystery
polyline = interpolateEllipse(entity.x, entity.y, entity.r, entity.r, entity.startAngle, entity.endAngle, undefined, false);
// I kid you not, ARCs and ELLIPSEs handle this differently,
// as evidenced by how AutoCAD actually renders these entities
if (entity.extrusionZ === -1) {
polyline = polyline.map(function (p) {
return [-p[0], p[1]];
});
}
}
if (entity.type === 'SPLINE') {
polyline = interpolateBSpline(entity.controlPoints, entity.degree, entity.knots, options.interpolationsPerSplineSegment, entity.weights);
}
if (!polyline) {
_logger["default"].warn('unsupported entity for converting to polyline:', entity.type);
return [];
}
return polyline;
};
exports["default"] = _default;