ranim_anims/
fading.rs

1use ranim_core::{
2    animation::Eval,
3    traits::{Interpolatable, Opacity},
4};
5
6// MARK: Require Trait
7/// The requirement of [`FadeIn`] and [`FadeOut`]
8pub trait FadingRequirement: Opacity + Interpolatable + Clone {}
9impl<T: Opacity + Interpolatable + Clone> FadingRequirement for T {}
10
11// MARK: Anim Trait
12/// The methods to create animations for `T` that satisfies [`FadingRequirement`]
13pub trait FadingAnim: FadingRequirement + Sized + 'static {
14    /// Create a [`FadeIn`] anim.
15    fn fade_in(&mut self) -> FadeIn<Self>;
16    /// Create a [`FadeOut`] anim.
17    fn fade_out(&mut self) -> FadeOut<Self>;
18}
19
20impl<T: FadingRequirement + Sized + 'static> FadingAnim for T {
21    fn fade_in(&mut self) -> FadeIn<Self> {
22        FadeIn::new(self.clone()).apply_to(self)
23    }
24    fn fade_out(&mut self) -> FadeOut<Self> {
25        FadeOut::new(self.clone()).apply_to(self)
26    }
27}
28
29// MARK: Impl
30
31/// Fade-in animation.
32///
33/// Because some Items may not be completly opaque, so
34/// this is implemented by setting the opacity to 0.0 as
35/// initial state, then interpolate between them.
36pub struct FadeIn<T: FadingRequirement> {
37    src: T,
38    dst: T,
39}
40
41impl<T: FadingRequirement> FadeIn<T> {
42    /// Constructor
43    pub fn new(target: T) -> Self {
44        let mut src = target.clone();
45        let dst = target.clone();
46        src.set_opacity(0.0);
47        Self { src, dst }
48    }
49}
50
51impl<T: FadingRequirement> Eval for FadeIn<T> {
52    type Output = T;
53
54    fn eval_alpha(&self, alpha: f64) -> Self::Output {
55        self.src.lerp(&self.dst, alpha)
56    }
57}
58
59/// Fade-out animation.
60///
61/// Because some Items may not be completly opaque, so
62/// this is implemented by setting the opacity to 0.0 as
63/// target state, then interpolate between them.
64pub struct FadeOut<T: FadingRequirement> {
65    src: T,
66    dst: T,
67}
68
69impl<T: FadingRequirement> FadeOut<T> {
70    /// Constructor
71    pub fn new(target: T) -> Self {
72        let src = target.clone();
73        let mut dst = target.clone();
74        dst.set_opacity(0.0);
75        Self { src, dst }
76    }
77}
78
79impl<T: FadingRequirement> Eval for FadeOut<T> {
80    type Output = T;
81
82    fn eval_alpha(&self, alpha: f64) -> Self::Output {
83        self.src.lerp(&self.dst, alpha)
84    }
85}
ranim_anims/fading.rs

ranim_anims/
fading.rs
