feat(eckhart): add easing and rollback to HtC anim

core/embed/rust/src/ui/layout_eckhart/component/hold_to_confirm.rs

@@ -5,6 +5,7 @@ use crate::{
         component::{Component, Event, EventCtx, Never},
         display::Color,
         geometry::{Offset, Rect},
+        lerp::Lerp,
         shape::{self, Renderer},
     },
 };
@@ -17,8 +18,8 @@ use super::{
 /// A component that displays a border that grows from the bottom of the screen
 /// to the top. The animation is parametrizable by color and duration.
 pub struct HoldToConfirmAnim {
-    /// Duration of the animation
-    duration: Duration,
+    /// Intended total duration of Hold to Confirm animation
+    total_duration: Duration,
     /// Screen border and header overlay color
     color: Color,
     /// Screen border shape
@@ -27,17 +28,47 @@ pub struct HoldToConfirmAnim {
     timer: Stopwatch,
     /// Header overlay text shown during the animation
     header_overlay: Option<TString<'static>>,
+    /// Rollback animation state
+    rollback: RollbackState,
+}
+
+/// State of the rollback animation, when `stop` is called.
+struct RollbackState {
+    /// Timer for the rollback animation
+    timer: Stopwatch,
+    /// Point in time of the growth animation when the rollback was initiated
+    duration: Duration,
 }
 
 impl HoldToConfirmAnim {
+    /// Growth duration of the bottom part of the border
+    const BOTTOM_DURATION: Duration = Duration::from_millis(200);
+    /// Growth duration of the side parts of the border
+    const SIDES_DURATION: Duration = Duration::from_millis(800);
+    /// Growth duration of the top part of the border
+    const TOP_DURATION: Duration = Duration::from_millis(600);
+
+    /// Duration of the rollback animation
+    const ROLLBACK_DURATION: Duration = Duration::from_millis(600);
+
     pub fn new() -> Self {
+        debug_assert!(
+            theme::CONFIRM_HOLD_DURATION.to_millis()
+                > (Self::BOTTOM_DURATION.to_millis()
+                    + Self::SIDES_DURATION.to_millis()
+                    + Self::TOP_DURATION.to_millis())
+        );
         let default_color = theme::GREEN_LIME;
         Self {
-            duration: theme::CONFIRM_HOLD_DURATION,
+            total_duration: theme::CONFIRM_HOLD_DURATION,
             color: default_color,
             border: ScreenBorder::new(default_color),
             timer: Stopwatch::default(),
             header_overlay: None,
+            rollback: RollbackState {
+                timer: Stopwatch::default(),
+                duration: Duration::default(),
+            },
         }
     }
 
@@ -48,7 +79,13 @@ impl HoldToConfirmAnim {
     }
 
     pub fn with_duration(mut self, duration: Duration) -> Self {
-        self.duration = duration;
+        debug_assert!(
+            duration.to_millis()
+                > (Self::BOTTOM_DURATION.to_millis()
+                    + Self::SIDES_DURATION.to_millis()
+                    + Self::TOP_DURATION.to_millis())
+        );
+        self.total_duration = duration;
         self
     }
 
@@ -62,64 +99,19 @@ impl HoldToConfirmAnim {
     }
 
     pub fn stop(&mut self) {
+        self.rollback.timer = Stopwatch::new_started();
+        self.rollback.duration = self.timer.elapsed();
         self.timer = Stopwatch::new_stopped();
     }
 
     fn is_active(&self) -> bool {
-        self.timer.is_running_within(self.duration)
+        self.timer.is_running_within(self.total_duration)
     }
 
-    fn get_clips(&self) -> (Rect, Option<Rect>) {
-        let ratio = self.timer.elapsed() / self.duration;
-
-        let bottom_width = self.border.bottom_width();
-        let total_height = SCREEN.height();
-        let total_width = SCREEN.width();
-
-        let circumference = 2 * total_height + total_width + bottom_width;
-        let bottom_ratio = bottom_width as f32 / circumference as f32;
-        let vertical_ratio = (2 * total_height) as f32 / circumference as f32;
-        let upper_ratio = total_width as f32 / circumference as f32;
-
-        let vertical_cut = bottom_ratio + vertical_ratio;
-
-        if ratio < bottom_ratio {
-            // Animate the bottom border growing horizontally.
-            let clip_width = ((ratio / bottom_ratio) * bottom_width as f32) as i16;
-            let clip_width = clip_width.clamp(0, bottom_width);
-            (
-                Rect::from_center_and_size(
-                    SCREEN
-                        .bottom_center()
-                        .ofs(Offset::y(-ScreenBorder::WIDTH / 2)),
-                    Offset::new(clip_width, ScreenBorder::WIDTH),
-                ),
-                None,
-            )
-        } else if ratio < vertical_cut {
-            // Animate the vertical border growing from the bottom up.
-            let progress = (ratio - bottom_ratio) / vertical_ratio;
-            let clip_height = (progress * total_height as f32) as i16;
-            let clip_height = clip_height.clamp(0, total_height - ScreenBorder::WIDTH);
-            (
-                Rect::from_bottom_left_and_size(
-                    SCREEN.bottom_left(),
-                    Offset::new(total_width, clip_height),
-                ),
-                None,
-            )
-        } else {
-            // Animate the top border growing horizontally towards center.
-            let progress = (ratio - vertical_cut) / upper_ratio;
-            let clip_width = total_width - ((progress * total_width as f32) as i16);
-            (
-                SCREEN,
-                Some(Rect::from_center_and_size(
-                    SCREEN.top_center().ofs(Offset::y(ScreenBorder::WIDTH / 2)),
-                    Offset::new(clip_width, ScreenBorder::WIDTH),
-                )),
-            )
-        }
+    fn is_rollback(&self) -> bool {
+        self.rollback
+            .timer
+            .is_running_within(Self::ROLLBACK_DURATION)
     }
 }
 
@@ -132,7 +124,7 @@ impl Component for HoldToConfirmAnim {
 
     fn event(&mut self, ctx: &mut EventCtx, event: Event) -> Option<Self::Msg> {
         if let Event::Timer(EventCtx::ANIM_FRAME_TIMER) = event {
-            if self.is_active() {
+            if self.is_active() || self.is_rollback() {
                 ctx.request_anim_frame();
                 ctx.request_paint();
             }
@@ -141,37 +133,152 @@ impl Component for HoldToConfirmAnim {
     }
 
     fn render<'s>(&'s self, target: &mut impl Renderer<'s>) {
+        // Rollback & Fading out animation
+        if self.is_rollback() {
+            let rollback_elapsed = self.rollback.timer.elapsed();
+            let alpha = self.get_rollback_alpha(rollback_elapsed);
+            let rollback_duration_progressed = self
+                .rollback
+                .duration
+                .checked_add(rollback_elapsed)
+                .unwrap_or(Duration::default());
+            let (clip, top_gap) = self.get_clips(rollback_duration_progressed);
+            let top_back_rollback = self.get_top_gap_rollback(rollback_elapsed);
+            let top_gap = top_gap.union(top_back_rollback);
+            self.render_clipped_border(clip, top_gap, alpha, target);
+        }
+
+        // Growing animation
         if self.is_active() {
             // override header with custom text
-            if let Some(text) = self.header_overlay {
-                let font = fonts::FONT_SATOSHI_REGULAR_22;
-                let header_pad = Rect::from_top_left_and_size(
-                    SCREEN.top_left(),
-                    Offset::new(SCREEN.width(), Header::HEADER_HEIGHT),
-                );
-                shape::Bar::new(header_pad)
-                    .with_bg(theme::BG)
-                    .render(target);
-                text.map(|text| {
-                    let text_pos = header_pad.top_left()
-                        + Offset::new(24, font.vert_center(0, Header::HEADER_HEIGHT, text));
-                    shape::Text::new(text_pos, text, font)
-                        .with_fg(self.color)
-                        .render(target);
-                });
+            // TODO: is the delay desirable?
+            if self.timer.elapsed() > Duration::from_millis(300) {
+                self.render_header_overlay(target);
             }
             // growing border
-            let (in_clip, out_clip_opt) = self.get_clips();
-            target.in_clip(in_clip, &|target| {
-                self.border.render(target);
-            });
-            // optional out clip for upper line rendering
-            if let Some(out_clip) = out_clip_opt {
-                shape::Bar::new(out_clip)
-                    .with_bg(theme::BG)
-                    .with_fg(theme::BG)
-                    .render(target);
-            }
+            let (clip, top_gap) = self.get_clips(self.timer.elapsed());
+            self.render_clipped_border(clip, top_gap, u8::MAX, target);
+        }
+    }
+}
+
+// Rendering helpers
+impl HoldToConfirmAnim {
+    fn render_header_overlay<'s>(&'s self, target: &mut impl Renderer<'s>) {
+        if let Some(text) = self.header_overlay {
+            let font = theme::label_title_main().text_font;
+            let header_pad = Rect::from_top_left_and_size(
+                SCREEN.top_left(),
+                Offset::new(SCREEN.width(), Header::HEADER_HEIGHT),
+            );
+            shape::Bar::new(header_pad)
+                .with_bg(theme::BG)
+                .render(target);
+            text.map(|text| {
+                let text_pos = header_pad.top_left()
+                    + Offset::new(24, font.vert_center(0, Header::HEADER_HEIGHT, text));
+                shape::Text::new(text_pos, text, font)
+                    .with_fg(self.color)
+                    .render(target);
+            });
+        }
+    }
+
+    fn render_clipped_border<'s>(
+        &'s self,
+        clip: Rect,
+        top_gap: Rect,
+        alpha: u8,
+        target: &mut impl Renderer<'s>,
+    ) {
+        target.in_clip(clip, &|target| {
+            self.border.render(alpha, target);
+        });
+        // optional out clip for upper line rendering
+        shape::Bar::new(top_gap)
+            .with_bg(theme::BG)
+            .with_fg(theme::BG)
+            .render(target);
+    }
+
+    fn get_rollback_alpha(&self, elapsed: Duration) -> u8 {
+        let progress = (elapsed / Self::ROLLBACK_DURATION).clamp(0.0, 1.0);
+        let shift = pareen::constant(0.0).seq_ease_out(
+            0.0,
+            easer::functions::Cubic,
+            1.0,
+            pareen::constant(1.0),
+        );
+        u8::lerp(u8::MAX, u8::MIN, shift.eval(progress))
+    }
+
+    fn get_top_gap_rollback(&self, elapsed: Duration) -> Rect {
+        let progress = (elapsed / Self::ROLLBACK_DURATION).clamp(0.0, 1.0);
+        let clip_width = (progress * SCREEN.width() as f32) as i16;
+        Rect::from_center_and_size(
+            SCREEN.top_center().ofs(Offset::y(ScreenBorder::WIDTH / 2)),
+            Offset::new(clip_width, ScreenBorder::WIDTH),
+        )
+    }
+
+    fn get_clips(&self, elapsed: Duration) -> (Rect, Rect) {
+        // Define segment-specific timings
+        let bottom_dur_ratio = Self::BOTTOM_DURATION / self.total_duration;
+        let sides_dur_ratio = Self::SIDES_DURATION / self.total_duration;
+        let top_dur_ratio = Self::TOP_DURATION / self.total_duration;
+
+        let progress = (elapsed / self.total_duration).clamp(0.0, 1.0);
+
+        const TOP_GAP_ZERO: Rect = Rect::from_center_and_size(
+            SCREEN.top_center().ofs(Offset::y(ScreenBorder::WIDTH / 2)),
+            Offset::zero(),
+        );
+        match progress {
+            // Bottom phase growing linearly
+            p if p < bottom_dur_ratio => {
+                let bottom_progress = (p / bottom_dur_ratio).clamp(0.0, 1.0);
+                let width = i16::lerp(0, SCREEN.width(), bottom_progress);
+                let clip = Rect::from_center_and_size(
+                    SCREEN
+                        .bottom_center()
+                        .ofs(Offset::y(-ScreenBorder::WIDTH / 2)),
+                    Offset::new(width, ScreenBorder::WIDTH),
+                );
+                (clip, TOP_GAP_ZERO)
+            }
+
+            // Sides phase growing up linearly
+            p if p < (bottom_dur_ratio + sides_dur_ratio) => {
+                let sides_progress = ((p - bottom_dur_ratio) / sides_dur_ratio).clamp(0.0, 1.0);
+                let height = i16::lerp(ScreenBorder::WIDTH, SCREEN.height(), sides_progress);
+                let clip = Rect::from_bottom_left_and_size(
+                    SCREEN.bottom_left(),
+                    Offset::new(SCREEN.width(), height),
+                );
+                (clip, TOP_GAP_ZERO)
+            }
+
+            // Top phase
+            p if p < 1.0 => {
+                let top_progress =
+                    ((p - bottom_dur_ratio - sides_dur_ratio) / top_dur_ratio).clamp(0.0, 1.0);
+                let ease = pareen::constant(0.0).seq_ease_out(
+                    0.0,
+                    easer::functions::Cubic,
+                    1.0,
+                    pareen::constant(1.0),
+                );
+                let eased_progress = ease.eval(top_progress);
+                let width = i16::lerp(SCREEN.width(), 0, eased_progress);
+                let top_gap = Rect::from_center_and_size(
+                    SCREEN.top_center().ofs(Offset::y(ScreenBorder::WIDTH / 2)),
+                    Offset::new(width, ScreenBorder::WIDTH),
+                );
+                (SCREEN, top_gap)
+            }
+
+            // Animation complete
+            _ => (SCREEN, TOP_GAP_ZERO),
         }
     }
 }

core/embed/rust/src/ui/layout_eckhart/theme/mod.rs

@@ -12,7 +12,7 @@ use super::{
     fonts,
 };
 
-pub const CONFIRM_HOLD_DURATION: Duration = Duration::from_millis(1500);
+pub const CONFIRM_HOLD_DURATION: Duration = Duration::from_millis(2500);
 pub const ERASE_HOLD_DURATION: Duration = Duration::from_millis(1500);
 
 // Color palette.