Transitions

Transitions occur when you have a conditional view like if_view!, match_view!, or ViewThatFits which changes branches. Because the branches contain different subtrees, there is no reasonable way to animate between them.

The properties of views within unchanged branches are still animated as normal.

Because Buoyant will not animate between branches, you should avoid using conditional views when all the branches are the same type:

#![allow(unused)]
fn main() {
extern crate buoyant;
extern crate embedded_graphics;
use buoyant::{
    if_view,
    view::{shape::Rectangle, View, ViewExt as _},
};
use embedded_graphics::pixelcolor::Rgb888;

/// This will jump between two different rectangles
fn bar1(is_wide: bool) -> impl View<Rgb888> {
    if_view!((is_wide) {
        Rectangle.frame_sized(100, 5)
    } else {
        Rectangle.frame_sized(20, 5)
    })
}

/// This will animate the frame of the Rectangle
fn bar2(is_wide: bool) -> impl View<Rgb888> {
    Rectangle.frame_sized(if is_wide { 100 } else { 20 }, 5)
}
}

Future Work

There is no animation when transitioning between branches today. However, this feature is planned for a future release and will allow you to animate the motion of the frame as the branch appears or disappears.