1
use glam::dvec3;
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use ranim::{
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    animation::transform::TransformAnimSchedule,
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    color::{HueDirection, palettes::manim},
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    components::Anchor,
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    items::{group::Group, vitem::Rectangle},
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    prelude::*,
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    utils::rate_functions::{ease_in_quad, ease_out_quad, linear},
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};
10

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fn solve_hanoi(
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    n: usize,
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    idx_src: usize,
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    idx_dst: usize,
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    idx_tmp: usize,
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    move_disk: &mut impl FnMut(usize, usize),
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) {
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    if n == 1 {
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        move_disk(idx_src, idx_dst);
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    } else {
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        solve_hanoi(n - 1, idx_src, idx_tmp, idx_dst, move_disk);
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        move_disk(idx_src, idx_dst);
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        solve_hanoi(n - 1, idx_tmp, idx_dst, idx_src, move_disk);
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    }
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}
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#[scene]
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struct HanoiScene(pub usize);
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impl TimelineConstructor for HanoiScene {
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    fn construct<'t: 'r, 'r>(
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        self,
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        timeline: &'t RanimTimeline,
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        _camera: &'r mut Rabject<'t, CameraFrame>,
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    ) {
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        let n = self.0;
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        let total_sec = 10.0;
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        let rod_width = 0.4;
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        let rod_height = 5.0;
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        let rod_section_width = 4.0;
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        let _rods = timeline.insert([-1, 0, 1].into_iter().map(|i| {
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            let mut rod = Rectangle(rod_width, rod_height).build();
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            rod.set_color(manim::GREY_C).put_anchor_on(
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                Anchor::edge(0, -1, 0),
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                dvec3(i as f64 * rod_section_width, -4.0, 0.0),
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            );
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            rod
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        }));
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        let min_disk_width = rod_width * 1.7;
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        let max_disk_width = rod_section_width * 0.8;
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        let disk_height = (rod_height * 0.8) / n as f64;
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        let _disks = timeline.insert((0..n).map(|i| {
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            let factor = i as f64 / (n - 1) as f64;
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            let disk_width = min_disk_width + (max_disk_width - min_disk_width) * (1.0 - factor);
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            let mut disk = Rectangle(disk_width, disk_height).build();
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            let color = manim::RED_D.lerp(manim::BLUE_D, factor as f32, HueDirection::Increasing);
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            disk.set_color(color).put_anchor_on(
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                Anchor::edge(0, -1, 0),
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                dvec3(-rod_section_width, -4.0 + disk_height * i as f64, 0.0),
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            );
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            disk
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        }));
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        let mut disks = [_disks, Group::new(), Group::new()];
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        let anim_duration = total_sec / (2.0f64.powi(n as i32) - 1.0) / 3.0;
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        let mut move_disk = |idx_src: usize, idx_dst: usize| {
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            let top_disk_y = |idx: usize| disks[idx].len() as f64 * disk_height - 4.0;
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            let top_src = top_disk_y(idx_src) - disk_height;
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            let top_dst = top_disk_y(idx_dst);
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            let mut disk = disks[idx_src].pop().unwrap();
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            timeline.play(
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                disk.transform(|data| {
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                    data.shift(dvec3(0.0, 3.0 - top_src, 0.0));
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                })
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                .with_duration(anim_duration)
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                .with_rate_func(ease_in_quad)
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                .apply(),
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            );
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            timeline.play(
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                disk.transform(|data| {
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                    data.shift(dvec3(
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                        (idx_dst as f64 - idx_src as f64) * rod_section_width,
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                        0.0,
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                        0.0,
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                    ));
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                })
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                .with_duration(anim_duration)
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                .with_rate_func(linear)
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                .apply(),
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            );
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            timeline.play(
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                disk.transform(|data| {
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                    data.shift(dvec3(0.0, top_dst - 3.0, 0.0));
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                })
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                .with_duration(anim_duration)
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                .with_rate_func(ease_out_quad)
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                .apply(),
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            );
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            timeline.sync();
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            disks[idx_dst].push(disk);
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        };
106

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        solve_hanoi(n, 0, 1, 2, &mut move_disk);
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    }
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}
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111
fn main() {
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    #[cfg(feature = "app")]
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    run_scene_app(HanoiScene(10));
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    #[cfg(not(feature = "app"))]
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    {
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        render_scene(
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            HanoiScene(5),
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            &AppOptions {
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                output_filename: "output-5.mp4",
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                ..Default::default()
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            },
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        );
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        render_scene_at_sec(HanoiScene(5), 0.0, "preview-5.png", &AppOptions::default());
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        render_scene(
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            HanoiScene(10),
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            &AppOptions {
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                output_filename: "output-10.mp4",
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                ..Default::default()
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            },
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        );
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        render_scene_at_sec(
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            HanoiScene(10),
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            0.0,
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            "preview-10.png",
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            &AppOptions::default(),
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        );
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    }
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}
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