vue-bokeh
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A wrapper around bokehjs embedded
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JavaScript
var arc_to_bezier, segment_to_bezier;
segment_to_bezier = function(cx, cy, th0, th1, rx, ry, sin_th, cos_th) {
var a00, a01, a10, a11, t, th_half, x1, x2, x3, y1, y2, y3;
a00 = cos_th * rx;
a01 = -sin_th * ry;
a10 = sin_th * rx;
a11 = cos_th * ry;
th_half = 0.5 * (th1 - th0);
t = (8 / 3) * Math.sin(th_half * 0.5) * Math.sin(th_half * 0.5) / Math.sin(th_half);
x1 = cx + Math.cos(th0) - t * Math.sin(th0);
y1 = cy + Math.sin(th0) + t * Math.cos(th0);
x3 = cx + Math.cos(th1);
y3 = cy + Math.sin(th1);
x2 = x3 + t * Math.sin(th1);
y2 = y3 - t * Math.cos(th1);
return [a00 * x1 + a01 * y1, a10 * x1 + a11 * y1, a00 * x2 + a01 * y2, a10 * x2 + a11 * y2, a00 * x3 + a01 * y3, a10 * x3 + a11 * y3];
};
arc_to_bezier = function(ox, oy, radx, rady, rotateX, large, sweep, x, y) {
var a00, a01, a10, a11, cos_th, d, i, pl, px, py, result, rx, ry, segments, sfactor, sfactor_sq, sin_th, th, th0, th1, th2, th3, th_arc, x0, x1, xc, y0, y1, yc;
th = rotateX * (Math.PI / 180);
sin_th = Math.sin(th);
cos_th = Math.cos(th);
rx = Math.abs(radx);
ry = Math.abs(rady);
px = cos_th * (ox - x) * 0.5 + sin_th * (oy - y) * 0.5;
py = cos_th * (oy - y) * 0.5 - sin_th * (ox - x) * 0.5;
pl = (px * px) / (rx * rx) + (py * py) / (ry * ry);
if (pl > 1) {
pl = Math.sqrt(pl);
rx *= pl;
ry *= pl;
}
a00 = cos_th / rx;
a01 = sin_th / rx;
a10 = -sin_th / ry;
a11 = cos_th / ry;
x0 = a00 * ox + a01 * oy;
y0 = a10 * ox + a11 * oy;
x1 = a00 * x + a01 * y;
y1 = a10 * x + a11 * y;
d = (x1 - x0) * (x1 - x0) + (y1 - y0) * (y1 - y0);
sfactor_sq = 1 / d - 0.25;
if (sfactor_sq < 0) {
sfactor_sq = 0;
}
sfactor = Math.sqrt(sfactor_sq);
if (sweep === large) {
sfactor = -sfactor;
}
xc = 0.5 * (x0 + x1) - sfactor * (y1 - y0);
yc = 0.5 * (y0 + y1) + sfactor * (x1 - x0);
th0 = Math.atan2(y0 - yc, x0 - xc);
th1 = Math.atan2(y1 - yc, x1 - xc);
th_arc = th1 - th0;
if (th_arc < 0 && sweep === 1) {
th_arc += 2 * Math.PI;
} else if (th_arc > 0 && sweep === 0) {
th_arc -= 2 * Math.PI;
}
segments = Math.ceil(Math.abs(th_arc / (Math.PI * 0.5 + 0.001)));
result = (function() {
var j, ref, results;
results = [];
for (i = j = 0, ref = segments; 0 <= ref ? j < ref : j > ref; i = 0 <= ref ? ++j : --j) {
th2 = th0 + i * th_arc / segments;
th3 = th0 + (i + 1) * th_arc / segments;
results.push(segment_to_bezier(xc, yc, th2, th3, rx, ry, sin_th, cos_th));
}
return results;
})();
return result;
};
module.exports = {
arc_to_bezier: arc_to_bezier,
segment_to_bezier: segment_to_bezier
};