| from __future__ import annotations |
|
|
| from typing import TYPE_CHECKING |
|
|
| from .scalar import ScalarOffset |
| from .._animator import Animation |
| from .._animator import EasingFunction |
| from .._types import CallbackType |
| from ..geometry import Offset |
|
|
| if TYPE_CHECKING: |
| from ..widget import Widget |
| from .styles import Styles |
|
|
|
|
| class ScalarAnimation(Animation): |
| def __init__( |
| self, |
| widget: Widget, |
| styles: Styles, |
| start_time: float, |
| attribute: str, |
| value: ScalarOffset, |
| duration: float | None, |
| speed: float | None, |
| easing: EasingFunction, |
| on_complete: CallbackType | None = None, |
| ): |
| assert ( |
| speed is not None or duration is not None |
| ), "One of speed or duration required" |
| self.widget = widget |
| self.styles = styles |
| self.start_time = start_time |
| self.attribute = attribute |
| self.final_value = value |
| self.easing = easing |
| self.on_complete = on_complete |
|
|
| size = widget.outer_size |
| viewport = widget.app.size |
|
|
| self.start: Offset = getattr(styles, attribute).resolve(size, viewport) |
| self.destination: Offset = value.resolve(size, viewport) |
|
|
| if speed is not None: |
| distance = self.start.get_distance_to(self.destination) |
| self.duration = distance / speed |
| else: |
| assert duration is not None, "Duration expected to be non-None" |
| self.duration = duration |
|
|
| def __call__(self, time: float) -> bool: |
| factor = min(1.0, (time - self.start_time) / self.duration) |
| eased_factor = self.easing(factor) |
|
|
| if eased_factor >= 1: |
| setattr(self.styles, self.attribute, self.final_value) |
| return True |
|
|
| offset = self.start + (self.destination - self.start) * eased_factor |
| current = self.styles._rules[self.attribute] |
| if current != offset: |
| setattr(self.styles, f"{self.attribute}", offset) |
|
|
| return False |
|
|
| def __eq__(self, other: object) -> bool: |
| if isinstance(other, ScalarAnimation): |
| return ( |
| self.final_value == other.final_value |
| and self.duration == other.duration |
| ) |
| return False |
|
|
