open-consul/ui-v2/app/helpers/svg-curve.js

42 lines
1.2 KiB
JavaScript

import { helper } from '@ember/component/helper';
// arguments should be a list of {x: numLike, y: numLike} points
// numLike meaning they should be numbers (or numberlike strings i.e. "1" vs 1)
const curve = function() {
const args = [...arguments];
// our arguments are destination first control points last
// SVGs are control points first destination last
// we 'shift,push' to turn that around and then map
// through the values to convert it to 'x y, x y' etc
// whether the curve is cubic-bezier (C) or quadratic-bezier (Q)
// then depends on the amount of control points
// `Q|C x y, x y, x y` etc
return `${arguments.length > 2 ? `C` : `Q`} ${args
.concat(args.shift())
.map(p => Object.values(p).join(' '))
.join(',')}`;
};
const move = function(d) {
return `
M ${d.x} ${d.y}
`;
};
export default helper(function([dest], hash) {
const src = hash.src || { x: 0, y: 0 };
const type = hash.type || 'cubic';
let args = [
dest,
{
x: (src.x + dest.x) / 2,
y: src.y,
},
];
if (type === 'cubic') {
args.push({
x: args[1].x,
y: dest.y,
});
}
return `${move(src)}${curve(...args)}`;
});