venny/bin/venn-set.js

Declarative Venn diagrams

import { VennElement } from './base-element';
export class VennSet extends VennElement {
    constructor() {
        super(...arguments);
        this._name = '';
        this._size = 10;
    }
    static get observedAttributes() {
        return ['name', 'size', 'label'];
    }
    get name() {
        return this._name;
    }
    set name(value) {
        if (value !== this._name) {
            this._name = value;
            this._firePropChange('name');
        }
    }
    computeAreas() {
        const areas = [
            {
                sets: [this.name],
                size: this.size,
                label: this.label,
                component: this,
            },
        ];
        const children = this.children;
        let setChildren = 0;
        for (let i = 0; i < children.length; i++) {
            if (children[i] instanceof VennSet) {
                setChildren++;
            }
        }
        for (let i = 0; i < children.length; i++) {
            if (children[i] instanceof VennElement) {
                const childSet = children[i];
                if (childSet.size >= this.size) {
                    switch (setChildren) {
                        case 0:
                        case 1:
                            childSet.size = this.size / 2;
                            break;
                        default:
                            childSet.size = this.size / ((setChildren + 1) * 2);
                            break;
                    }
                }
                const childAreas = childSet.computeAreas();
                if (childAreas && childAreas.length) {
                    for (const ca of childAreas) {
                        areas.push(ca);
                        areas.push({
                            sets: [this.name, ...ca.sets],
                            size: Math.min(this.size, ca.size),
                        });
                    }
                }
            }
        }
        return areas;
    }
}
customElements.define('venn-set', VennSet);