wavyte 0.2.1

Programmatic video composition and rendering engine in Rust (CPU backend, ffmpeg MP4 encoding)
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143

use super::*;
use crate::{
    animation::anim::Anim,
    animation::ease::Ease,
    composition::model::{Asset, ClipProps, TextAsset, Track},
    foundation::core::{Canvas, Fps, Transform2D, Vec2},
};
use std::collections::BTreeMap;

fn basic_comp(
    opacity: Anim<f64>,
    tr_in: Option<TransitionSpec>,
    tr_out: Option<TransitionSpec>,
) -> Composition {
    let mut assets = BTreeMap::new();
    assets.insert(
        "t0".to_string(),
        Asset::Text(TextAsset {
            text: "hello".to_string(),
            font_source: "assets/PlayfairDisplay.ttf".to_string(),
            size_px: 48.0,
            max_width_px: None,
            color_rgba8: [255, 255, 255, 255],
        }),
    );
    Composition {
        fps: Fps::new(30, 1).unwrap(),
        canvas: Canvas {
            width: 640,
            height: 360,
        },
        duration: FrameIndex(20),
        assets,
        tracks: vec![Track {
            name: "main".to_string(),
            z_base: 0,
            layout_mode: crate::LayoutMode::Absolute,
            layout_gap_px: 0.0,
            layout_padding: crate::Edges::default(),
            layout_align_x: crate::LayoutAlignX::Start,
            layout_align_y: crate::LayoutAlignY::Start,
            layout_grid_columns: 2,
            clips: vec![Clip {
                id: "c0".to_string(),
                asset: "t0".to_string(),
                range: FrameRange::new(FrameIndex(5), FrameIndex(15)).unwrap(),
                props: ClipProps {
                    transform: Anim::constant(Transform2D {
                        translate: Vec2::new(1.0, 2.0),
                        ..Transform2D::default()
                    }),
                    opacity,
                    blend: BlendMode::Normal,
                },
                z_offset: 0,
                effects: vec![],
                transition_in: tr_in,
                transition_out: tr_out,
            }],
        }],
        seed: 1,
    }
}

#[test]
fn visibility_respects_frame_range() {
    let comp = basic_comp(Anim::constant(1.0), None, None);
    assert_eq!(
        Evaluator::eval_frame(&comp, FrameIndex(4))
            .unwrap()
            .nodes
            .len(),
        0
    );
    assert_eq!(
        Evaluator::eval_frame(&comp, FrameIndex(5))
            .unwrap()
            .nodes
            .len(),
        1
    );
    assert_eq!(
        Evaluator::eval_frame(&comp, FrameIndex(14))
            .unwrap()
            .nodes
            .len(),
        1
    );
    assert_eq!(
        Evaluator::eval_frame(&comp, FrameIndex(15))
            .unwrap()
            .nodes
            .len(),
        0
    );
}

#[test]
fn opacity_is_clamped() {
    let opacity = Anim::constant(2.0);
    let comp = basic_comp(opacity, None, None);
    let g = Evaluator::eval_frame(&comp, FrameIndex(5)).unwrap();
    assert_eq!(g.nodes[0].opacity, 1.0);
}

#[test]
fn transition_progress_boundaries() {
    let tr = TransitionSpec {
        kind: "crossfade".to_string(),
        duration_frames: 3,
        ease: Ease::Linear,
        params: serde_json::Value::Null,
    };
    let comp = basic_comp(Anim::constant(1.0), Some(tr.clone()), Some(tr));

    // In transition at clip start frame.
    let g0 = Evaluator::eval_frame(&comp, FrameIndex(5)).unwrap();
    assert_eq!(g0.nodes[0].transition_in.as_ref().unwrap().progress, 0.0);

    // Last in-transition frame hits progress 1.0 (dur=3 => denom=2).
    let g_last_in = Evaluator::eval_frame(&comp, FrameIndex(7)).unwrap();
    assert_eq!(
        g_last_in.nodes[0].transition_in.as_ref().unwrap().progress,
        1.0
    );

    // Out transition starts at end-dur.
    let g_out0 = Evaluator::eval_frame(&comp, FrameIndex(12)).unwrap();
    assert_eq!(
        g_out0.nodes[0].transition_out.as_ref().unwrap().progress,
        0.0
    );

    let g_out_last = Evaluator::eval_frame(&comp, FrameIndex(14)).unwrap();
    assert_eq!(
        g_out_last.nodes[0]
            .transition_out
            .as_ref()
            .unwrap()
            .progress,
        1.0
    );
}