m3-svelte/package/misc/easing.js

M3 Svelte implements the Material 3 design system in Svelte. See the [website](https://ktibow.github.io/m3-svelte/) for demos and usage instructions.

const createBezierLUT = (points, pointCount = 100) => {
    const lut = [];
    for (let t = 0; t < 1; t += 1 / pointCount) {
        const a = (1 - t) * (1 - t) * (1 - t);
        const b = (1 - t) * (1 - t) * t;
        const c = (1 - t) * t * t;
        const d = t * t * t;
        const x = a * points[0][0] + 3 * b * points[1][0] + 3 * c * points[2][0] + d * points[3][0];
        const y = a * points[0][1] + 3 * b * points[1][1] + 3 * c * points[2][1] + d * points[3][1];
        lut.push([x, y]);
    }
    return lut;
};
const createEase = (lutOptions) => {
    let lut;
    return (t) => {
        if (!lut)
            lut = lutOptions.map((args) => createBezierLUT(args)).flat();
        const closestPoint = lut.find((p) => p[0] >= t);
        const closestY = closestPoint ? closestPoint[1] : 1;
        return closestY;
    };
};
export const easeEmphasized = createEase([
    [
        [0, 0],
        [0.05, 0],
        [0.133, 0.06],
        [0.166, 0.4],
    ],
    [
        [0.166, 0.4],
        [0.208, 0.82],
        [0.25, 1],
        [1, 1],
    ],
]); /* css versions:
with limited overshoot:
https://cdn.discordapp.com/attachments/1058124584286683237/1064238491904524308/w9blD3eMKQBwAAAABJRU5ErkJggg.png
cubic-bezier(0.254, 0.029, 0, 1.2) is preferred, it is the most accurate to the acceleration
cubic-bezier(0.356, 0.701, 0, 1.004) is the most accurate to the deceleration
cubic-bezier(0.291, 0.281, 0, 1.2) has no weighting
unlimited overshoot:
https://cdn.discordapp.com/attachments/1058124584286683237/1064238129306927124/H47ZvYKwT8COjeuQXsI8AE4554luCbtMqAAqAJubZ9I2452QBcREREJgab5REREREKgZEpEREQkBEqmREREREKgZEpEREQkBEqmREREREKgZEpEREQkBEqmREREREKgZEpEREQkBP8PcBLo5kfHxSYAAAAASUVORK5CYII.png
cubic-bezier(0.271, -0.011, 0, 1.449) is the most accurate to the acceleration (but has a large overshoot)
the deceleration is the same as before
cubic-bezier(0.278, 0.195, 0, 1.251) has no weighting
the m3 docs randomly mention 0.2, 0, 0, 1 but that seems off
*/
export const easeEmphasizedDecel = createEase([
    [
        [0, 0],
        [0.05, 0.7],
        [0.1, 1],
        [1, 1],
    ],
]);
export const easeEmphasizedAccel = createEase([
    [
        [0, 0],
        [0.3, 0],
        [0.8, 0.15],
        [1, 1],
    ],
]);
export const easeStandard = createEase([
    [
        [0, 0],
        [0.2, 0],
        [0, 1],
        [1, 1],
    ],
]);
export const easeStandardDecel = createEase([
    [
        [0, 0],
        [0, 0],
        [0, 1],
        [1, 1],
    ],
]);
export const easeStandardAccel = createEase([
    [
        [0, 0],
        [0.3, 0],
        [1, 1],
        [1, 1],
    ],
]);