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Easing Functions

Module: terminaltexteffects.utils.easing

Functions and Classes for easing calculations.

Classes:

Name Description
EasingTracker

Tracks the progression of an easing function over a set number of steps.
SequenceEaser

Eases over a sequence, tracking added, removed, and total elements

Functions:

Name Description
linear

Linear easing function.
in_sine

Ease in using a sine function.
out_sine

Ease out using a sine function.
in_out_sine

Ease in/out using a sine function.
in_quad

Ease in using a quadratic function.
out_quad

Ease out using a quadratic function.
in_out_quad

Ease in/out using a quadratic function.
in_cubic

Ease in using a cubic function.
out_cubic

Ease out using a cubic function.
in_out_cubic

Ease in/out using a cubic function.
in_quart

Ease in using a quartic function.
out_quart

Ease out using a quartic function.
in_out_quart

Ease in/out using a quartic function.
in_quint

Ease in using a quintic function.
out_quint

Ease out using a quintic function.
in_out_quint

Ease in/out using a quintic function.
in_expo

Ease in using an exponential function.
out_expo

Ease out using an exponential function.
in_out_expo

Ease in/out using an exponential function.
in_circ

Ease in using a circular function.
out_circ

Ease out using a circular function.
in_out_circ

Ease in/out using a circular function.
in_back

Ease in using a back function.
out_back

Ease out using a back function.
in_out_back

Ease in/out using a back function.
in_elastic

Ease in using an elastic function.
out_elastic

Ease out using an elastic function.
in_out_elastic

Ease in/out using an elastic function.
in_bounce

Ease in using a bounce function.
out_bounce

Ease out using a bounce function.
in_out_bounce

Ease in/out using a bounce function.
make_easing

Create a cubic Bezier easing function using the provided control points.

EasingFunction = typing.Callable[[float], float] module-attribute

EasingFunctions take a float between 0 and 1 and return a float between 0 and 1.

make_easing = functools.wraps(make_easing)(functools.lru_cache(maxsize=8192)(make_easing)) module-attribute

Create a cubic Bezier easing function using the provided control points.

The easing function maps an input progress ratio (0 to 1) to an output value (0 to 1) according to a cubic Bezier curve defined by four points: - Start point: (0, 0) - First control point: (x1, y1) - Second control point: (x2, y2) - End point: (1, 1)

Parameters:

Name Type Description Default
x1 float

Determines the horizontal position of the first control point. Smaller values make the curve start off steeper, while larger values delay the initial acceleration.

 required
y1 float

Determines the vertical position of the first control point. Smaller values create a gentler ease-in effect; larger values increase the initial acceleration.

 required
x2 float

Determines the horizontal position of the second control point. Larger values extend the period of change, affecting how late the acceleration or deceleration begins.

 required
y2 float

Determines the vertical position of the second control point. Larger values can create a more abrupt ease-out effect; smaller values result in a smoother finish.

 required

Note: Use a resource such as cubic-bezier.com to design an appropriate easing curve for your needs.

Returns:

Name Type Description
EasingFunction EasingFunction

A function that takes a progress_ratio (0 <= progress_ratio <= 1) and returns
EasingFunction

the eased value computed from the cubic Bezier curve.

EasingTracker dataclass

Describe the progression of items as an easing function is applied over a sequence.

Attributes:

Name Type Description
easing_function EasingFunction

The easing function being tracked.
total_steps int

The total number of steps for the easing function.
current_step int

The current step in the easing progression.
progress_ratio float

The ratio of the current step to the total steps.
step_delta float

The change in eased value from the last step to the current step.
eased_value float

The current eased value based on the easing function and progress ratio.

Methods:

Name Description
step

Advance the easing tracker by one step and return the new eased value.
is_complete

Check if the easing tracker has completed all steps.
Source code in terminaltexteffects/utils/easing.py 
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@dataclass
class EasingTracker:
    """Describe the progression of items as an easing function is applied over a sequence.

    Attributes:
        easing_function (EasingFunction): The easing function being tracked.
        total_steps (int): The total number of steps for the easing function.
        current_step (int): The current step in the easing progression.
        progress_ratio (float): The ratio of the current step to the total steps.
        step_delta (float): The change in eased value from the last step to the current step.
        eased_value (float): The current eased value based on the easing function and progress ratio.

    Methods:
        step() -> float: Advance the easing tracker by one step and return the new eased value.
        is_complete() -> bool: Check if the easing tracker has completed all steps.

    """

    easing_function: EasingFunction
    total_steps: int = 100
    clamp: InitVar[bool] = field(default=False)

    def __post_init__(self, clamp: bool) -> None:
        """Initialize the EasingTracker.

        Args:
            clamp (bool, optional): If True, clamp the eased value between 0 and 1. Defaults to False.

        """
        self._clamp = clamp
        self.current_step: int = 0
        self.progress_ratio: float = 0.0
        self.step_delta: float = 0.0
        self.eased_value: float = 0.0
        self._last_eased_value: float = 0.0

    def step(self) -> float:
        """Advance the easing tracker by one step.

        If the current step is less than the total steps, increment the current step,
        update the progress ratio, compute the new eased value using the easing function,
        and calculate the step delta.

        If clamp is enabled, the eased value is constrained between 0 and 1.

        Returns:
            float: The new eased value after advancing one step.

        """
        if self.current_step < self.total_steps:
            self.current_step += 1
            self.progress_ratio = self.current_step / self.total_steps
            self.eased_value = self.easing_function(self.progress_ratio)
            if self._clamp:
                self.eased_value = max(0.0, min(self.eased_value, 1.0))
            self.step_delta = self.eased_value - self._last_eased_value
            self._last_eased_value = self.eased_value
        return self.eased_value

    def reset(self) -> None:
        """Reset the easing tracker to the initial state."""
        self.current_step = 0
        self.progress_ratio = 0.0
        self.step_delta = 0.0
        self.eased_value = 0.0
        self._last_eased_value = 0.0

    def is_complete(self) -> bool:
        """Check if the easing tracker has completed all steps.

        Returns:
            bool: True if all steps have been completed, False otherwise.

        """
        return self.current_step >= self.total_steps

    def __iter__(self) -> typing.Iterator[float]:
        """Iterate over eased values until completion.

        Yields:
            float: The eased value at each step.

        """
        while not self.is_complete():
            yield self.step()

__iter__()

Iterate over eased values until completion.

Yields:

Name Type Description
float float

The eased value at each step.
Source code in terminaltexteffects/utils/easing.py 
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def __iter__(self) -> typing.Iterator[float]:
    """Iterate over eased values until completion.

    Yields:
        float: The eased value at each step.

    """
    while not self.is_complete():
        yield self.step()

__post_init__(clamp)

Initialize the EasingTracker.

Parameters:

Name Type Description Default
clamp bool

If True, clamp the eased value between 0 and 1. Defaults to False.

 required
Source code in terminaltexteffects/utils/easing.py 
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def __post_init__(self, clamp: bool) -> None:
    """Initialize the EasingTracker.

    Args:
        clamp (bool, optional): If True, clamp the eased value between 0 and 1. Defaults to False.

    """
    self._clamp = clamp
    self.current_step: int = 0
    self.progress_ratio: float = 0.0
    self.step_delta: float = 0.0
    self.eased_value: float = 0.0
    self._last_eased_value: float = 0.0

is_complete()

Check if the easing tracker has completed all steps.

Returns:

Name Type Description
bool bool

True if all steps have been completed, False otherwise.
Source code in terminaltexteffects/utils/easing.py 
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def is_complete(self) -> bool:
    """Check if the easing tracker has completed all steps.

    Returns:
        bool: True if all steps have been completed, False otherwise.

    """
    return self.current_step >= self.total_steps

reset()

Reset the easing tracker to the initial state.

Source code in terminaltexteffects/utils/easing.py 
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def reset(self) -> None:
    """Reset the easing tracker to the initial state."""
    self.current_step = 0
    self.progress_ratio = 0.0
    self.step_delta = 0.0
    self.eased_value = 0.0
    self._last_eased_value = 0.0

step()

Advance the easing tracker by one step.

If the current step is less than the total steps, increment the current step, update the progress ratio, compute the new eased value using the easing function, and calculate the step delta.

If clamp is enabled, the eased value is constrained between 0 and 1.

Returns:

Name Type Description
float float

The new eased value after advancing one step.
Source code in terminaltexteffects/utils/easing.py 
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def step(self) -> float:
    """Advance the easing tracker by one step.

    If the current step is less than the total steps, increment the current step,
    update the progress ratio, compute the new eased value using the easing function,
    and calculate the step delta.

    If clamp is enabled, the eased value is constrained between 0 and 1.

    Returns:
        float: The new eased value after advancing one step.

    """
    if self.current_step < self.total_steps:
        self.current_step += 1
        self.progress_ratio = self.current_step / self.total_steps
        self.eased_value = self.easing_function(self.progress_ratio)
        if self._clamp:
            self.eased_value = max(0.0, min(self.eased_value, 1.0))
        self.step_delta = self.eased_value - self._last_eased_value
        self._last_eased_value = self.eased_value
    return self.eased_value

SequenceEaser dataclass

Bases: Generic[_T]

Eases over a sequence, tracking added, removed, and total elements.

Attributes:

Name Type Description
sequence Sequence[_T]

The sequence to ease over.
easing_function EasingFunction

The easing function to use.
total_steps int

The total number of steps for the easing function.
added Sequence[_T]

Elements added in the current step.
removed Sequence[_T]

Elements removed in the current step.
total Sequence[_T]

Current active elements based on eased length.
Source code in terminaltexteffects/utils/easing.py 
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@dataclass
class SequenceEaser(typing.Generic[_T]):
    """Eases over a sequence, tracking added, removed, and total elements.

    Attributes:
        sequence (Sequence[_T]): The sequence to ease over.
        easing_function (EasingFunction): The easing function to use.
        total_steps (int): The total number of steps for the easing function.
        added (Sequence[_T]): Elements added in the current step.
        removed (Sequence[_T]): Elements removed in the current step.
        total (Sequence[_T]): Current active elements based on eased length.

    """

    sequence: typing.Sequence[_T]
    easing_function: EasingFunction
    total_steps: int = 100
    added: typing.Sequence[_T] = field(init=False, default_factory=list)
    removed: typing.Sequence[_T] = field(init=False, default_factory=list)
    total: typing.Sequence[_T] = field(init=False, default_factory=list)

    def __post_init__(self) -> None:
        """Initialize the SequenceEaser."""
        self.easing_tracker = EasingTracker(
            easing_function=self.easing_function,
            total_steps=self.total_steps,
            clamp=True,
        )

    def step(self) -> typing.Sequence[_T]:
        """Advance the easing tracker by one step and update added, removed, and total elements.

        Returns:
            typing.Sequence[_T]: The elements added in the current step.

        """
        previous_eased = self.easing_tracker.eased_value
        eased_value = self.easing_tracker.step()
        seq_len = len(self.sequence)
        if seq_len == 0:
            self.added = self.sequence[:0]
            self.removed = self.sequence[:0]
            self.total = self.sequence[:0]
            return self.added

        length = int(eased_value * seq_len)
        previous_length = int(previous_eased * seq_len)

        if length > previous_length:
            self.added = self.sequence[previous_length:length]
            self.removed = self.sequence[:0]
        elif length < previous_length:
            self.added = self.sequence[:0]
            self.removed = self.sequence[length:previous_length]
        else:
            self.added = self.sequence[:0]
            self.removed = self.sequence[:0]

        self.total = self.sequence[:length]
        return self.added

    def is_complete(self) -> bool:
        """Check if the easing over the sequence is complete.

        Returns:
            bool: True if all steps have been completed, False otherwise.

        """
        return self.easing_tracker.is_complete()

    def reset(self) -> None:
        """Reset the SequenceEaser to the initial state."""
        self.easing_tracker.reset()
        self.added = self.sequence[:0]
        self.removed = self.sequence[:0]
        self.total = self.sequence[:0]

__post_init__()

Initialize the SequenceEaser.

Source code in terminaltexteffects/utils/easing.py 
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def __post_init__(self) -> None:
    """Initialize the SequenceEaser."""
    self.easing_tracker = EasingTracker(
        easing_function=self.easing_function,
        total_steps=self.total_steps,
        clamp=True,
    )

is_complete()

Check if the easing over the sequence is complete.

Returns:

Name Type Description
bool bool

True if all steps have been completed, False otherwise.
Source code in terminaltexteffects/utils/easing.py 
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def is_complete(self) -> bool:
    """Check if the easing over the sequence is complete.

    Returns:
        bool: True if all steps have been completed, False otherwise.

    """
    return self.easing_tracker.is_complete()

reset()

Reset the SequenceEaser to the initial state.

Source code in terminaltexteffects/utils/easing.py 
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def reset(self) -> None:
    """Reset the SequenceEaser to the initial state."""
    self.easing_tracker.reset()
    self.added = self.sequence[:0]
    self.removed = self.sequence[:0]
    self.total = self.sequence[:0]

step()

Advance the easing tracker by one step and update added, removed, and total elements.

Returns:

Type Description
Sequence[_T]

typing.Sequence[_T]: The elements added in the current step.
Source code in terminaltexteffects/utils/easing.py 
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def step(self) -> typing.Sequence[_T]:
    """Advance the easing tracker by one step and update added, removed, and total elements.

    Returns:
        typing.Sequence[_T]: The elements added in the current step.

    """
    previous_eased = self.easing_tracker.eased_value
    eased_value = self.easing_tracker.step()
    seq_len = len(self.sequence)
    if seq_len == 0:
        self.added = self.sequence[:0]
        self.removed = self.sequence[:0]
        self.total = self.sequence[:0]
        return self.added

    length = int(eased_value * seq_len)
    previous_length = int(previous_eased * seq_len)

    if length > previous_length:
        self.added = self.sequence[previous_length:length]
        self.removed = self.sequence[:0]
    elif length < previous_length:
        self.added = self.sequence[:0]
        self.removed = self.sequence[length:previous_length]
    else:
        self.added = self.sequence[:0]
        self.removed = self.sequence[:0]

    self.total = self.sequence[:length]
    return self.added

in_back(progress_ratio)

Ease in using a back function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_back(progress_ratio: float) -> float:
    """Ease in using a back function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    c1 = 1.70158
    c3 = c1 + 1
    return c3 * progress_ratio**3 - c1 * progress_ratio**2

in_bounce(progress_ratio)

Ease in using a bounce function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 representing the percentage of the current waypoint speed to apply to the character
Source code in terminaltexteffects/utils/easing.py 
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def in_bounce(progress_ratio: float) -> float:
    """Ease in using a bounce function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 representing the percentage of the current waypoint speed to apply to the character

    """
    return 1 - out_bounce(1 - progress_ratio)

in_circ(progress_ratio)

Ease in using a circular function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_circ(progress_ratio: float) -> float:
    """Ease in using a circular function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return 1 - math.sqrt(1 - progress_ratio**2)

in_cubic(progress_ratio)

Ease in using a cubic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_cubic(progress_ratio: float) -> float:
    """Ease in using a cubic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return progress_ratio**3

in_elastic(progress_ratio)

Ease in using an elastic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_elastic(progress_ratio: float) -> float:
    """Ease in using an elastic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    c4 = (2 * math.pi) / 3
    if progress_ratio == 0:
        return 0
    if progress_ratio == 1:
        return 1
    return -(2 ** (10 * progress_ratio - 10)) * math.sin((progress_ratio * 10 - 10.75) * c4)

in_expo(progress_ratio)

Ease in using an exponential function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_expo(progress_ratio: float) -> float:
    """Ease in using an exponential function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    if progress_ratio == 0:
        return 0
    return 2 ** (10 * progress_ratio - 10)

in_out_back(progress_ratio)

Ease in/out using a back function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_out_back(progress_ratio: float) -> float:
    """Ease in/out using a back function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    c1 = 1.70158
    c2 = c1 * 1.525
    if progress_ratio < 0.5:
        return ((2 * progress_ratio) ** 2 * ((c2 + 1) * 2 * progress_ratio - c2)) / 2
    return ((2 * progress_ratio - 2) ** 2 * ((c2 + 1) * (progress_ratio * 2 - 2) + c2) + 2) / 2

in_out_bounce(progress_ratio)

Ease in/out using a bounce function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_out_bounce(progress_ratio: float) -> float:
    """Ease in/out using a bounce function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    if progress_ratio < 0.5:
        return (1 - out_bounce(1 - 2 * progress_ratio)) / 2
    return (1 + out_bounce(2 * progress_ratio - 1)) / 2

in_out_circ(progress_ratio)

Ease in/out using a circular function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_out_circ(progress_ratio: float) -> float:
    """Ease in/out using a circular function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    if progress_ratio < 0.5:
        return (1 - math.sqrt(1 - (2 * progress_ratio) ** 2)) / 2
    return (math.sqrt(1 - (-2 * progress_ratio + 2) ** 2) + 1) / 2

in_out_cubic(progress_ratio)

Ease in/out using a cubic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 representing the percentage of the current waypoint speed to apply to the
float

character
Source code in terminaltexteffects/utils/easing.py 
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def in_out_cubic(progress_ratio: float) -> float:
    """Ease in/out using a cubic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 representing the percentage of the current waypoint speed to apply to the
        character

    """
    if progress_ratio < 0.5:
        return 4 * progress_ratio**3
    return 1 - (-2 * progress_ratio + 2) ** 3 / 2

in_out_elastic(progress_ratio)

Ease in/out using an elastic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 representing the percentage of the current waypoint speed to apply to the character
Source code in terminaltexteffects/utils/easing.py 
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def in_out_elastic(progress_ratio: float) -> float:
    """Ease in/out using an elastic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 representing the percentage of the current waypoint speed to apply to the character

    """
    c5 = (2 * math.pi) / 4.5
    if progress_ratio == 0:
        return 0
    if progress_ratio == 1:
        return 1
    if progress_ratio < 0.5:
        return -(2 ** (20 * progress_ratio - 10) * math.sin((20 * progress_ratio - 11.125) * c5)) / 2
    return (2 ** (-20 * progress_ratio + 10) * math.sin((20 * progress_ratio - 11.125) * c5)) / 2 + 1

in_out_expo(progress_ratio)

Ease in/out using an exponential function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_out_expo(progress_ratio: float) -> float:
    """Ease in/out using an exponential function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    if progress_ratio == 0:
        return 0
    if progress_ratio == 1:
        return 1
    if progress_ratio < 0.5:
        return 2 ** (20 * progress_ratio - 10) / 2
    return (2 - 2 ** (-20 * progress_ratio + 10)) / 2

in_out_quad(progress_ratio)

Ease in/out using a quadratic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_out_quad(progress_ratio: float) -> float:
    """Ease in/out using a quadratic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    if progress_ratio < 0.5:
        return 2 * progress_ratio**2
    return 1 - (-2 * progress_ratio + 2) ** 2 / 2

in_out_quart(progress_ratio)

Ease in/out using a quartic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_out_quart(progress_ratio: float) -> float:
    """Ease in/out using a quartic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    if progress_ratio < 0.5:
        return 8 * progress_ratio**4
    return 1 - (-2 * progress_ratio + 2) ** 4 / 2

in_out_quint(progress_ratio)

Ease in/out using a quintic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_out_quint(progress_ratio: float) -> float:
    """Ease in/out using a quintic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    if progress_ratio < 0.5:
        return 16 * progress_ratio**5
    return 1 - (-2 * progress_ratio + 2) ** 5 / 2

in_out_sine(progress_ratio)

Ease in/out using a sine function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_out_sine(progress_ratio: float) -> float:
    """Ease in/out using a sine function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return -(math.cos(math.pi * progress_ratio) - 1) / 2

in_quad(progress_ratio)

Ease in using a quadratic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_quad(progress_ratio: float) -> float:
    """Ease in using a quadratic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return progress_ratio**2

in_quart(progress_ratio)

Ease in using a quartic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 representing the percentage
float

of the current waypoint speed to apply to the character
Source code in terminaltexteffects/utils/easing.py 
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def in_quart(progress_ratio: float) -> float:
    """Ease in using a quartic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 representing the percentage
        of the current waypoint speed to apply to the character

    """
    return progress_ratio**4

in_quint(progress_ratio)

Ease in using a quintic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_quint(progress_ratio: float) -> float:
    """Ease in using a quintic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return progress_ratio**5

in_sine(progress_ratio)

Ease in using a sine function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def in_sine(progress_ratio: float) -> float:
    """Ease in using a sine function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return 1 - math.cos((progress_ratio * math.pi) / 2)

linear(progress_ratio)

Linear easing function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def linear(progress_ratio: float) -> float:
    """Linear easing function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return progress_ratio

out_back(progress_ratio)

Ease out using a back function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_back(progress_ratio: float) -> float:
    """Ease out using a back function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    c1 = 1.70158
    c3 = c1 + 1
    return 1 + c3 * (progress_ratio - 1) ** 3 + c1 * (progress_ratio - 1) ** 2

out_bounce(progress_ratio)

Ease out using a bounce function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_bounce(progress_ratio: float) -> float:
    """Ease out using a bounce function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    n1 = 7.5625
    d1 = 2.75
    if progress_ratio < 1 / d1:
        return n1 * progress_ratio**2
    if progress_ratio < 2 / d1:
        return n1 * (progress_ratio - 1.5 / d1) ** 2 + 0.75
    if progress_ratio < 2.5 / d1:
        return n1 * (progress_ratio - 2.25 / d1) ** 2 + 0.9375
    return n1 * (progress_ratio - 2.625 / d1) ** 2 + 0.984375

out_circ(progress_ratio)

Ease out using a circular function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_circ(progress_ratio: float) -> float:
    """Ease out using a circular function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return math.sqrt(1 - (progress_ratio - 1) ** 2)

out_cubic(progress_ratio)

Ease out using a cubic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_cubic(progress_ratio: float) -> float:
    """Ease out using a cubic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return 1 - (1 - progress_ratio) ** 3

out_elastic(progress_ratio)

Ease out using an elastic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 representing the percentage of the current waypoint speed to apply to the character
Source code in terminaltexteffects/utils/easing.py 
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def out_elastic(progress_ratio: float) -> float:
    """Ease out using an elastic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 representing the percentage of the current waypoint speed to apply to the character

    """
    c4 = (2 * math.pi) / 3
    if progress_ratio == 0:
        return 0
    if progress_ratio == 1:
        return 1
    return 2 ** (-10 * progress_ratio) * math.sin((progress_ratio * 10 - 0.75) * c4) + 1

out_expo(progress_ratio)

Ease out using an exponential function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_expo(progress_ratio: float) -> float:
    """Ease out using an exponential function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    if progress_ratio == 1:
        return 1
    return 1 - 2 ** (-10 * progress_ratio)

out_quad(progress_ratio)

Ease out using a quadratic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_quad(progress_ratio: float) -> float:
    """Ease out using a quadratic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return 1 - (1 - progress_ratio) * (1 - progress_ratio)

out_quart(progress_ratio)

Ease out using a quartic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_quart(progress_ratio: float) -> float:
    """Ease out using a quartic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return 1 - (1 - progress_ratio) ** 4

out_quint(progress_ratio)

Ease out using a quintic function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_quint(progress_ratio: float) -> float:
    """Ease out using a quintic function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return 1 - (1 - progress_ratio) ** 5

out_sine(progress_ratio)

Ease out using a sine function.

Parameters:

Name Type Description Default
progress_ratio float

the ratio of the current step to the maximum steps

 required

Returns:

Name Type Description
float float

0 <= n <= 1 eased value
Source code in terminaltexteffects/utils/easing.py 
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def out_sine(progress_ratio: float) -> float:
    """Ease out using a sine function.

    Args:
        progress_ratio (float): the ratio of the current step to the maximum steps

    Returns:
        float: 0 <= n <= 1 eased value

    """
    return math.sin((progress_ratio * math.pi) / 2)