-module(ease).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/ease.gleam").
-export([linear/1, quadratic/1, cubic/1, quartic/1, quintic/1, sine/1, exponential/1, circular/1, back/1, elastic/1, bounce/1, spring/1, reverse/1, join_at/3, join/2, symmetry/1]).

-if(?OTP_RELEASE >= 27).
-define(MODULEDOC(Str), -moduledoc(Str)).
-define(DOC(Str), -doc(Str)).
-else.
-define(MODULEDOC(Str), -compile([])).
-define(DOC(Str), -compile([])).
-endif.

?MODULEDOC(
    " Easing functions for more natural animation transitions, derived from\n"
    " [Easings.net](https://easings.net).\n"
    "\n"
    " <style>\n"
    "   @font-face {\n"
    "     font-family: \"Iosevka\";\n"
    "     font-style: normal;\n"
    "     font-display: swap;\n"
    "     font-weight: 400;\n"
    "     src: url(https://cdn.jsdelivr.net/fontsource/fonts/iosevka@latest/latin-400-normal.woff2) format('woff2'), url(https://cdn.jsdelivr.net/fontsource/fonts/iosevka@latest/latin-400-normal.woff) format('woff');\n"
    "   }\n"
    "\n"
    "   .language-ansi {\n"
    "     font-family: \"Iosevka\", \"monospace\";\n"
    "     line-height: 1.0;\n"
    "   }\n"
    " </style>\n"
).

-file("src/ease.gleam", 45).
?DOC(
    " Linear easing is an identity transformation, time is not skewed.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ _________________________________________________⢀⡀\n"
    "       _                                            ⣀⣀⠤⠔⠒⠉⠁\n"
    "  0.75 _                                      ⣀⡠⠤⠒⠊⠉\n"
    "       _                               ⢀⣀⡠⠤⠒⠊⠉\n"
    "   0.5 _                         ⢀⣀⠤⠔⠒⠉⠁\n"
    "       _                   ⣀⣀⠤⠔⠒⠉⠁\n"
    "  0.25 _             ⣀⡠⠤⠒⠊⠉\n"
    "       _      ⢀⣀⡠⠤⠒⠊⠉\n"
    "     0 _ ⣀⠤⠔⠒⠉⠁_____________________________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
).
-spec linear(float()) -> float().
linear(T) ->
    T.

-file("src/ease.gleam", 69).
?DOC(
    " Eases in quadratically.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                               ⢀⡠⠔⠉\n"
    "  0.75 _                                            ⣀⠤⠒⠁\n"
    "       _                                        ⢀⡠⠒⠉\n"
    "   0.5 _                                    ⣀⠤⠒⠊⠁\n"
    "       _                               ⣀⡠⠔⠒⠉\n"
    "  0.25 _                         ⢀⣀⠤⠔⠒⠉\n"
    "       _                  ⣀⣀⠤⠤⠒⠒⠉⠁\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⡠⠤⠤⠤⠤⠒⠒⠒⠉⠉⠉__________________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInQuad).\n"
).
-spec quadratic(float()) -> float().
quadratic(T) ->
    T * T.

-file("src/ease.gleam", 93).
?DOC(
    " Eases in cubically.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                                 ⡠⠊\n"
    "  0.75 _                                              ⢀⠔⠉\n"
    "       _                                           ⢀⡠⠊⠁\n"
    "   0.5 _                                        ⢀⡠⠒⠁\n"
    "       _                                     ⣀⠔⠊⠁\n"
    "  0.25 _                                ⣀⡠⠔⠊⠉\n"
    "       _                         ⣀⣀⡠⠤⠒⠊⠉\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⡠⠤⠤⠤⠤⠤⠔⠒⠒⠊⠉⠉___________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInCubic).\n"
).
-spec cubic(float()) -> float().
cubic(T) ->
    (T * T) * T.

-file("src/ease.gleam", 117).
?DOC(
    " Eases in quartically.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                                 ⢀⠊\n"
    "  0.75 _                                               ⢀⠔⠁\n"
    "       _                                             ⢀⠔⠁\n"
    "   0.5 _                                           ⡠⠒⠁\n"
    "       _                                        ⣀⠔⠊\n"
    "  0.25 _                                    ⣀⠤⠒⠉\n"
    "       _                              ⣀⣀⠤⠔⠒⠉\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⠤⠤⠤⠤⠤⠔⠒⠒⠊⠉⠉______________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInQuart).\n"
).
-spec quartic(float()) -> float().
quartic(T) ->
    ((T * T) * T) * T.

-file("src/ease.gleam", 141).
?DOC(
    " Eases in quintically.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                                  ⠔\n"
    "  0.75 _                                                ⠠⠊\n"
    "       _                                              ⢀⠔⠁\n"
    "   0.5 _                                            ⢀⠔⠁\n"
    "       _                                          ⡠⠔⠁\n"
    "  0.25 _                                      ⢀⡠⠔⠊\n"
    "       _                                 ⢀⣀⠤⠔⠊⠁\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⠤⠤⠤⠤⠤⠔⠒⠒⠊⠉⠁__________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInQuint).\n"
).
-spec quintic(float()) -> float().
quintic(T) ->
    (((T * T) * T) * T) * T.

-file("src/ease.gleam", 165).
?DOC(
    " Eases in with a sine function.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                               ⣀⠤⠒⠉\n"
    "  0.75 _                                          ⢀⡠⠔⠒⠉\n"
    "       _                                      ⢀⡠⠔⠊⠁\n"
    "   0.5 _                                  ⣀⠤⠔⠊⠁\n"
    "       _                             ⣀⡠⠔⠒⠉\n"
    "  0.25 _                       ⢀⣀⠤⠔⠒⠉\n"
    "       _                ⢀⣀⡠⠤⠒⠒⠉⠁\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⠤⠤⠤⠤⠒⠒⠒⠉⠉⠁___________________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInSine).\n"
).
-spec sine(float()) -> float().
sine(T) ->
    Half_pi = 1.5707963267948966,
    1.0 - gleam_community@maths:cos(T * Half_pi).

-file("src/ease.gleam", 191).
?DOC(
    " Eases in exponentially.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                                  ⡐\n"
    "  0.75 _                                                 ⡐\n"
    "       _                                               ⢀⠌\n"
    "   0.5 _                                              ⡠⠂\n"
    "       _                                            ⡠⠊\n"
    "  0.25 _                                         ⡠⠔⠉\n"
    "       _                                   ⢀⣀⠤⠔⠒⠉\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⠤⠤⠤⠤⠤⠤⠤⠤⠒⠒⠒⠒⠉⠉⠁________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInExpo).\n"
).
-spec exponential(float()) -> float().
exponential(T) ->
    case T of
        +0.0 ->
            +0.0;

        _ ->
            X@1 = case gleam@float:power(2.0, (10.0 * T) - 10.0) of
                {ok, X} -> X;
                _assert_fail ->
                    erlang:error(#{gleam_error => let_assert,
                                message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                                file => <<?FILEPATH/utf8>>,
                                module => <<"ease"/utf8>>,
                                function => <<"exponential"/utf8>>,
                                line => 195,
                                value => _assert_fail,
                                start => 7331,
                                'end' => 7385,
                                pattern_start => 7342,
                                pattern_end => 7347})
            end,
            X@1
    end.

-file("src/ease.gleam", 221).
?DOC(
    " Eases in on an elliptic arc.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _\n"
    "  0.75 _                                                 ⢀⠊\n"
    "       _                                               ⢀⠔⠁\n"
    "   0.5 _                                            ⣀⠤⠊⠁\n"
    "       _                                       ⢀⣀⠤⠒⠉\n"
    "  0.25 _                                 ⢀⣀⠤⠤⠒⠊⠁\n"
    "       _                        ⣀⣀⣀⠤⠤⠔⠒⠊⠉⠁\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⣀⣀⣀⠤⠤⠤⠤⠤⠤⠔⠒⠒⠒⠊⠉⠉⠉____________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInCirc).\n"
).
-spec circular(float()) -> float().
circular(T) ->
    X@1 = case gleam@float:square_root(1.0 - (T * T)) of
        {ok, X} -> X;
        _assert_fail ->
            erlang:error(#{gleam_error => let_assert,
                        message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                        file => <<?FILEPATH/utf8>>,
                        module => <<"ease"/utf8>>,
                        function => <<"circular"/utf8>>,
                        line => 222,
                        value => _assert_fail,
                        start => 8305,
                        'end' => 8356,
                        pattern_start => 8316,
                        pattern_end => 8321})
    end,
    1.0 - X@1.

-file("src/ease.gleam", 246).
?DOC(
    " Eases away from the goal before accelerating toward it.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                                 ⢀⠌\n"
    "  0.75 _                                                ⡠⠂\n"
    "       _                                              ⢀⠔\n"
    "   0.5 _                                            ⢀⠔⠁\n"
    "       _                                          ⢀⠔⠁\n"
    "  0.25 _                                        ⡠⠔⠁\n"
    "       _                                     ⡠⠔⠊\n"
    "     0 _ ⣀⣀⣀⣀⣀⡀_________________________⣀⡠⠔⠒⠉_______________\n"
    "               ⠈⠉⠉⠉⠉⠑⠒⠒⠒⠒⠤⠤⠤⠤⠤⠤⠤⠤⠤⠤⠤⠔⠒⠒⠉⠉\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInBack).\n"
).
-spec back(float()) -> float().
back(T) ->
    C1 = 1.70158,
    C3 = C1 + 1.0,
    (((C3 * T) * T) * T) - ((C1 * T) * T).

-file("src/ease.gleam", 273).
?DOC(
    " Eases by oscillating with increasing amplitude around the start.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                                  ⠠\n"
    "  0.75 _                                                  ⠄\n"
    "       _                                                 ⠠\n"
    "   0.5 _                                                 ⡀\n"
    "       _\n"
    "  0.25 _                                                ⠈\n"
    "       _                                   ⢀⣀⣀⡀         ⠁\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⠤⢄⣀⣀⣀______⣀⠤⠊⠁__⠈⠢_______⠐____\n"
    "                                  ⠉⠉⠉⠉⠉⠉        ⠑⡀     ⠂\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''⠐⠄'''⡈''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8⠢⣀0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInElastic).\n"
).
-spec elastic(float()) -> float().
elastic(T) ->
    C4 = 2.0943951,
    case T of
        +0.0 ->
            +0.0;

        1.0 ->
            1.0;

        _ ->
            P@1 = case gleam@float:power(2.0, (10.0 * T) - 10.0) of
                {ok, P} -> P;
                _assert_fail ->
                    erlang:error(#{gleam_error => let_assert,
                                message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                                file => <<?FILEPATH/utf8>>,
                                module => <<"ease"/utf8>>,
                                function => <<"elastic"/utf8>>,
                                line => 280,
                                value => _assert_fail,
                                start => 10577,
                                'end' => 10631,
                                pattern_start => 10588,
                                pattern_end => 10593})
            end,
            (+0.0 - P@1) * gleam_community@maths:sin(((T * 10.0) - 10.75) * C4)
    end.

-file("src/ease.gleam", 306).
?DOC(
    " Eases in by \"bouncing\" around the start.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ ________________________________________________⣀⣀⡀\n"
    "       _                                            ⢀⠤⠒⠊⠉\n"
    "  0.75 _                                          ⡠⠊⠁\n"
    "       _                                        ⡠⠊\n"
    "   0.5 _                                      ⡠⠊\n"
    "       _                                    ⢀⠔\n"
    "  0.25 _                     ⢀⣀⣀⣀⣀⡀        ⠠⠂\n"
    "       _                 ⣀⠤⠒⠉⠁    ⠈⠉⠒⠤⣀   ⡐⠁\n"
    "     0 _ ⣀⣀⣀⣀⣀⡠⠤⠒⠒⠒⠒⠢⠤⢄⠤⠊______________⠑⢄⠔__________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " See more info on [Easings.net](https://easings.net/#easeInBounce).\n"
).
-spec bounce(float()) -> float().
bounce(T) ->
    N1 = 7.5625,
    D1 = 2.75,
    A = case D1 of
        +0.0 -> +0.0;
        -0.0 -> -0.0;
        Gleam@denominator -> 1.0 / Gleam@denominator
    end,
    B = 2.0 * A,
    C = 2.5 * A,
    X = case 1.0 - T of
        T@1 when T@1 < A ->
            (N1 * T@1) * T@1;

        T@2 when T@2 < B ->
            T@3 = T@2 - (case D1 of
                +0.0 -> +0.0;
                -0.0 -> -0.0;
                Gleam@denominator@1 -> 1.5 / Gleam@denominator@1
            end),
            ((N1 * T@3) * T@3) + 0.75;

        T@4 when T@4 < C ->
            T@5 = T@4 - (case D1 of
                +0.0 -> +0.0;
                -0.0 -> -0.0;
                Gleam@denominator@2 -> 2.25 / Gleam@denominator@2
            end),
            ((N1 * T@5) * T@5) + 0.9375;

        T@6 ->
            T@7 = T@6 - (case D1 of
                +0.0 -> +0.0;
                -0.0 -> -0.0;
                Gleam@denominator@3 -> 2.625 / Gleam@denominator@3
            end),
            ((N1 * T@7) * T@7) + 0.984375
    end,
    1.0 - X.

-file("src/ease.gleam", 351).
?DOC(
    " Eases in like a spring around the start.\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                                 ⡠⠊\n"
    "  0.75 _                                               ⡠⠊\n"
    "       _                                             ⡠⠊\n"
    "   0.5 _                                          ⣀⠔⠉\n"
    "       _                                       ⢀⠤⠊\n"
    "  0.25 _                                    ⣀⠤⠊⠁\n"
    "       _                                ⢀⡠⠔⠊\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⣀⣀⠤⠤⠤⠤⢄⣀⣀____________⣀⡠⠔⠊⠁___________________\n"
    "                        ⠉⠉⠒⠒⠢⠤⠤⠤⠒⠒⠊⠉\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
).
-spec spring(float()) -> float().
spring(T) ->
    Pi = 3.1415926535897932,
    {T@1, S1} = {1.0 - T, T},
    S2@1 = case gleam@float:power(S1, 2.2) of
        {ok, S2} -> S2;
        _assert_fail ->
            erlang:error(#{gleam_error => let_assert,
                        message => <<"Pattern match failed, no pattern matched the value."/utf8>>,
                        file => <<?FILEPATH/utf8>>,
                        module => <<"ease"/utf8>>,
                        function => <<"spring"/utf8>>,
                        line => 355,
                        value => _assert_fail,
                        start => 13053,
                        'end' => 13093,
                        pattern_start => 13064,
                        pattern_end => 13070})
    end,
    1.0 - (((gleam_community@maths:sin(
        (T@1 * Pi) * (0.2 + (((2.5 * T@1) * T@1) * T@1))
    )
    * S2@1)
    + T@1)
    * (1.0 + (1.2 * S1))).

-file("src/ease.gleam", 389).
?DOC(
    " Inverts an easing function, so ease-in becomes ease-out and ease-out\n"
    " becomes ease-in.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " quartic |> reverse\n"
    " ```\n"
    "\n"
    " Output functions graph:\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ ________________________________⢀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⡀\n"
    "       _                    ⢀⣀⡠⠤⠤⠒⠒⠒⠉⠉⠉⠉⠉⠁\n"
    "  0.75 _               ⢀⡠⠔⠒⠉⠁\n"
    "       _           ⢀⡠⠔⠊⠁\n"
    "   0.5 _         ⡠⠒⠁\n"
    "       _      ⢀⠔⠊\n"
    "  0.25 _    ⢀⠔⠁\n"
    "       _  ⢀⠔⠁\n"
    "     0 _ ⡠⠂_________________________________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
).
-spec reverse(fun((float()) -> float())) -> fun((float()) -> float()).
reverse(Ease) ->
    fun(T) -> 1.0 - Ease(1.0 - T) end.

-file("src/ease.gleam", 503).
?DOC(
    " Join two easing functions at a given point.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " join(linear, bounce |> reverse, 0.25)\n"
    " ```\n"
    "\n"
    " Output functions graph:\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________⡀____________⢀⡀_____⣀⣀⣀⣀⡀\n"
    "       _                          ⡐⠈⠑⠤⣀      ⢀⡠⠔⠁⠈⠉⠉⠉⠉⠉\n"
    "  0.75 _                        ⢀⠌     ⠉⠒⠒⠒⠒⠉⠁\n"
    "       _                       ⡠⠂\n"
    "   0.5 _                     ⢀⠔\n"
    "       _                   ⡠⠔⠁\n"
    "  0.25 _             ⣀⣀⡠⠤⠒⠉\n"
    "       _      ⢀⣀⡠⠤⠒⠊⠉\n"
    "     0 _ ⣀⠤⠔⠒⠉⠁_____________________________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
).
-spec join_at(fun((float()) -> float()), fun((float()) -> float()), float()) -> fun((float()) -> float()).
join_at(Ease_start, Ease_end, At) ->
    fun(T) -> case T < At of
            true ->
                Ease_start(case At of
                        +0.0 -> +0.0;
                        -0.0 -> -0.0;
                        Gleam@denominator -> T / Gleam@denominator
                    end) * At;

            false ->
                (Ease_end(case (1.0 - At) of
                        +0.0 -> +0.0;
                        -0.0 -> -0.0;
                        Gleam@denominator@1 -> (T - At) / Gleam@denominator@1
                    end) * (1.0 - At)) + At
        end end.

-file("src/ease.gleam", 473).
?DOC(
    " Join two easing functions.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " join(back, elastic |> reverse)\n"
    " ```\n"
    "\n"
    " Output functions graph:\n"
    "\n"
    " ```ansi\n"
    "\n"
    "                                    ⢀⠒⢄\n"
    "     1 _ ___________________________⠄__⢂___⣀⠤⠤⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⡀\n"
    "       _                           ⠠    ⠑⠒⠊\n"
    "  0.75 _                           ⡀\n"
    "       _\n"
    "   0.5 _                          ⡈\n"
    "       _                        ⢀⠌\n"
    "  0.25 _                       ⡠⠁\n"
    "       _                    ⢀⠔⠊\n"
    "     0 _ ⣀⣀⣀⣀___________⣀⡠⠤⠊⠁_______________________________\n"
    "             ⠉⠉⠉⠉⠉⠒⠒⠒⠉⠉⠉\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
).
-spec join(fun((float()) -> float()), fun((float()) -> float())) -> fun((float()) -> float()).
join(Ease_start, Ease_end) ->
    join_at(Ease_start, Ease_end, 0.5).

-file("src/ease.gleam", 442).
?DOC(
    " Making an easing function symmetry by joining it to its reversed self, so\n"
    " ease-in becomes ease-in-out and ease-out becomes ease-out-in.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " quartic |> symmetry\n"
    " ```\n"
    "\n"
    " Output functions graph:\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ _______________________________________⢀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⡀\n"
    "       _                                 ⣀⠤⠔⠒⠊⠉⠉⠁\n"
    "  0.75 _                              ⡠⠔⠉\n"
    "       _                           ⢀⠔⠊\n"
    "   0.5 _                          ⡠⠂\n"
    "       _                        ⢀⠊\n"
    "  0.25 _                      ⡠⠒⠁\n"
    "       _                  ⢀⡠⠔⠉\n"
    "     0 _ ⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⠤⠤⠤⠒⠒⠉⠁_________________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
    "\n"
    " ```gleam\n"
    " quartic |> reverse |> symmetry\n"
    " ```\n"
    "\n"
    " Output functions graph:\n"
    "\n"
    " ```ansi\n"
    "\n"
    "     1 _ __________________________________________________⡀\n"
    "       _                                                 ⢀⠊\n"
    "  0.75 _                                               ⡠⠒⠁\n"
    "       _                                           ⢀⡠⠔⠉\n"
    "   0.5 _               ⢀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⣀⠤⠤⠤⠒⠒⠉⠁\n"
    "       _        ⣀⠤⠔⠒⠊⠉⠉⠁\n"
    "  0.25 _     ⡠⠔⠉\n"
    "       _  ⢀⠔⠊\n"
    "     0 _ ⡠⠂_________________________________________________\n"
    "\n"
    "         |''''|''''|''''|''''|''''|''''|''''|''''|''''|''''|\n"
    "         0   0.1  0.2  0.3  0.4  0.5  0.6  0.7  0.8  0.9   1\n"
    " ```\n"
).
-spec symmetry(fun((float()) -> float())) -> fun((float()) -> float()).
symmetry(Ease) ->
    join(
        Ease,
        begin
            _pipe = Ease,
            reverse(_pipe)
        end
    ).