awv3/animation/easing.js

⚡ AWV3 embedded CAD

export const back = {
    in(k) {
        let s = 1.70158;
        return k * k * ((s + 1) * k - s);
    },

    out(k) {
        let s = 1.70158;
        return --k * k * ((s + 1) * k + s) + 1;
    },

    inOut(k) {
        let s = 1.70158 * 1.525;
        if ((k *= 2) < 1) return 0.5 * (k * k * ((s + 1) * k - s));
        return 0.5 * ((k -= 2) * k * ((s + 1) * k + s) + 2);
    }
};

export const bounce = {
    in(k) {
        return 1 - outward(1 - k);
    },

    out(k) {
        if (k < 1 / 2.75) return 7.5625 * k * k;
        else if (k < 2 / 2.75) return 7.5625 * (k -= 1.5 / 2.75) * k + 0.75;
        else if (k < 2.5 / 2.75) return 7.5625 * (k -= 2.25 / 2.75) * k + 0.9375;
        else return 7.5625 * (k -= 2.625 / 2.75) * k + 0.984375;
    },

    inOut(k) {
        if (k < 0.5) return inward(k * 2) * 0.5;
        return outward(k * 2 - 1) * 0.5 + 0.5;
    }
};

export const circular = {
    in(k) {
        return 1 - Math.sqrt(1 - k * k);
    },

    out(k) {
        return Math.sqrt(1 - --k * k);
    },

    inOut(k) {
        if ((k *= 2) < 1) return (-0.5) * (Math.sqrt(1 - k * k) - 1);
        return 0.5 * (Math.sqrt(1 - (k -= 2) * k) + 1);
    }
};

export const cubic = {
    in(k) {
        return k * k * k;
    },

    out(k) {
        return --k * k * k + 1;
    },

    inOut(k) {
        if ((k *= 2) < 1) return 0.5 * k * k * k;
        return 0.5 * ((k -= 2) * k * k + 2);
    }
};

export const elastic = {
    in(k) {
        let s, a = 0.1, p = 0.4;
        if (k === 0) return 0;
        if (k === 1) return 1;
        if (!a || a < 1) {
            a = 1;
            s = p / 4;
        } else
            s = p * Math.asin(1 / a) / (2 * Math.PI);
        return -(a * Math.pow(2, 10 * (k -= 1)) * Math.sin((k - s) * (2 * Math.PI) / p));
    },

    out(k) {
        let s, a = 0.1, p = 0.4;
        if (k === 0) return 0;
        if (k === 1) return 1;
        if (!a || a < 1) {
            a = 1;
            s = p / 4;
        } else
            s = p * Math.asin(1 / a) / (2 * Math.PI);
        return a * Math.pow(2, (-10) * k) * Math.sin((k - s) * (2 * Math.PI) / p) + 1;
    },

    inOut(k) {
        let s, a = 0.1, p = 0.4;
        if (k === 0) return 0;
        if (k === 1) return 1;
        if (!a || a < 1) {
            a = 1;
            s = p / 4;
        } else
            s = p * Math.asin(1 / a) / (2 * Math.PI);
        if ((k *= 2) < 1) return (-0.5) * (a * Math.pow(2, 10 * (k -= 1)) * Math.sin((k - s) * (2 * Math.PI) / p));
        return a * Math.pow(2, (-10) * (k -= 1)) * Math.sin((k - s) * (2 * Math.PI) / p) * 0.5 + 1;
    }
};

export const exponential = {
    in(k) {
        return k === 0 ? 0 : Math.pow(1024, k - 1);
    },

    out(k) {
        return k === 1 ? 1 : 1 - Math.pow(2, (-10) * k);
    },

    inOut(k) {
        if (k === 0) return 0;
        if (k === 1) return 1;
        if ((k *= 2) < 1) return 0.5 * Math.pow(1024, k - 1);
        return 0.5 * (-Math.pow(2, (-10) * (k - 1)) + 2);
    }
};

export const linear = function(k) {
    return k;
};

export const quadratic = {
    in(k) {
        return k * k;
    },

    out(k) {
        return k * (2 - k);
    },

    inOut(k) {
        if ((k *= 2) < 1) return 0.5 * k * k;
        return (-0.5) * (--k * (k - 2) - 1);
    }
};

export const quartic = {
    in(k) {
        return k * k * k * k;
    },

    out(k) {
        return 1 - --k * k * k * k;
    },

    inOut(k) {
        if ((k *= 2) < 1) return 0.5 * k * k * k * k;
        return (-0.5) * ((k -= 2) * k * k * k - 2);
    }
};

export const quintic = {
    in(k) {
        return k * k * k * k * k;
    },

    out(k) {
        return --k * k * k * k * k + 1;
    },

    inOut(k) {
        if ((k *= 2) < 1) return 0.5 * k * k * k * k * k;
        return 0.5 * ((k -= 2) * k * k * k * k + 2);
    }
};

export const sinusoidal = {
    in(k) {
        return 1 - Math.cos(k * Math.PI / 2);
    },

    out(k) {
        return Math.sin(k * Math.PI / 2);
    },

    inOut(k) {
        return 0.5 * (1 - Math.cos(Math.PI * k));
    }
};