Method lerp

docs/app/js/sanddance-app.js:69303–69310

(a, b, t)

        return this.check();
    }
    lerp(a, b, t) {
        if (t === undefined) return this.lerp(this, a, b);
        for(let i = 0; i < this.ELEMENTS; ++i){
            const ai = a[i];
            this[i] = ai + t * (b[i] - ai);
        }
        return this.check();
    }
    min(vector) {
        for(let i = 0; i < this.ELEMENTS; ++i)this[i] = Math.min(vector[i], this[i]);
        return this.check();