knot-toolbox/frontend/lib/math/math.js

export const Vec2 = {
    Mutate: {
        add(target, [x, y]) {
            target[0] += x;
            target[1] += y;

            return target;
        },
        scale(target, factor) {
            target[0] *= factor;
            target[1] *= factor;

            return target;
        },
        normalize(target) {
            const norm = Vec2.norm2([x, y]);
            target[0] /= norm;
            target[1] /= norm;

            return target;
        },
        set(target, [x, y]) {
            target[0] = x;
            target[1] = y;
            return target;
        },
    },
    perpendicular([x, y]) {
        return [-y, x];
    },
    distance2(v1, v2) {
        return Vec2.norm2(Vec2.sub(v1, v2));
    },
    add([x1, y1], [x2, y2]) {
        return [x1 + x2, y1 + y2];
    },
    sub([x1, y1], [x2, y2]) {
        return [x1 - x2, y1 - y2];
    },
    dot([x1, y1], [x2, y2]) {
        return x1 * x2 + y1 * y2;
    },
    scale([x, y], factor) {
        return [x * factor, y * factor];
    },
    norm2([x, y]) {
        return Math.sqrt(x ** 2 + y ** 2);
    },
    normalize([x, y]) {
        const norm = Vec2.norm2([x, y]);
        return [x / norm, y / norm];
    },

    findNearest(curve, pt) {
        let index = -1;
        let minDist = +Infinity;

        for (let i = 0; i < curve.length; i++) {
            const d = Vec2.distance2(curve[i], pt);

            if (d < minDist) {
                index = i;
                minDist = d;
            }
        }

        return [index, minDist];
    },
};

export const Vec3 = {
    Mutate: {
        add(target, [x, y, z]) {
            target[0] += x;
            target[1] += y;
            target[2] += z;

            return target;
        },
        scale(target, factor) {
            target[0] *= factor;
            target[1] *= factor;
            target[2] *= factor;

            return target;
        },
        normalize(target) {
            const norm = Vec3.norm2(target);
            target[0] /= norm;
            target[1] /= norm;
            target[2] /= norm;

            return target;
        },
    },
    withMaxLength(v, max) {
        const d = Vec3.norm2(v);

        if (d > max) {
            return Vec3.scale(v, max / d);
        }

        return v;
    },
    distance2(v1, v2) {
        return Vec3.norm2(Vec3.sub(v1, v2));
    },
    add([x1, y1, z1], [x2, y2, z2]) {
        return [x1 + x2, y1 + y2, z1 + z2];
    },
    sub([x1, y1, z1], [x2, y2, z2]) {
        return [x1 - x2, y1 - y2, z1 - z2];
    },
    dot([x1, y1, z1], [x2, y2, z2]) {
        return x1 * x2 + y1 * y2 + z1 * z2;
    },
    scale([x, y, z], factor) {
        return [x * factor, y * factor, z * factor];
    },
    norm2([x, y, z]) {
        return Math.sqrt(x ** 2 + y ** 2 + z ** 2);
    },
    normalize([x, y, z]) {
        const norm = Vec3.norm2([x, y, z]);
        return [x / norm, y / norm, z / norm];
    },
    findNearest(curve, pt) {
        let index = -1;
        let minDist = +Infinity;

        for (let i = 0; i < curve.length; i++) {
            const d = Vec3.distance2(curve[i], pt);

            if (d < minDist) {
                index = i;
                minDist = d;
            }
        }

        return [index, minDist];
    },
};

export function clamp(min, value, max) {
    return Math.min(max, Math.max(min, value));
}