cosmic-workspaces/src/widgets/toplevels/toplevel_layout/axis_toplevel_layout.rs
2025-09-11 14:03:30 -07:00

125 lines
3.4 KiB
Rust

use aliasable::vec::AliasableVec;
use cosmic::iced::{Length, Point, Rectangle, Size, advanced::layout::flex::Axis};
use std::marker::PhantomData;
use super::{LayoutToplevel, ToplevelLayout};
#[derive(Debug, Copy, Clone)]
pub struct AxisPoint {
pub main: f32,
pub cross: f32,
}
impl AxisPoint {
fn pack(self, axis: &Axis) -> Point {
match axis {
Axis::Horizontal => Point::new(self.main, self.cross),
Axis::Vertical => Point::new(self.cross, self.main),
}
}
}
#[derive(Debug, Copy, Clone)]
pub struct AxisSize<T = f32> {
pub main: T,
pub cross: T,
}
impl<T> AxisSize<T> {
fn unpack(axis: &Axis, size: Size<T>) -> Self {
match axis {
Axis::Horizontal => AxisSize {
main: size.width,
cross: size.height,
},
Axis::Vertical => AxisSize {
main: size.height,
cross: size.width,
},
}
}
fn pack(self, axis: &Axis) -> Size<T> {
match axis {
Axis::Horizontal => Size::new(self.main, self.cross),
Axis::Vertical => Size::new(self.cross, self.main),
}
}
}
#[derive(Debug, Copy, Clone)]
pub struct AxisRectangle {
pub origin: AxisPoint,
pub size: AxisSize,
}
impl AxisRectangle {
pub fn new(origin: AxisPoint, size: AxisSize) -> Self {
Self { origin, size }
}
fn pack(self, axis: &Axis) -> Rectangle {
Rectangle::new(self.origin.pack(axis), self.size.pack(axis))
}
}
/// Helper to implement [`ToplevelLayout`] for layouts based on an `[Axis]`,
/// that care only about main vs cross, and not width/height.
pub trait AxisToplevelLayout {
fn axis(&self) -> &Axis;
fn size(&self) -> AxisSize<Length>;
fn layout(
&self,
max_limit: AxisSize,
toplevels: &[LayoutToplevel<'_, AxisSize>],
) -> impl Iterator<Item = AxisRectangle>;
}
impl<T: AxisToplevelLayout> ToplevelLayout for T {
fn size(&self) -> Size<Length> {
self.size().pack(self.axis())
}
fn layout<'a>(
&self,
max_limit: Size,
toplevels: &[LayoutToplevel<'a>],
) -> impl Iterator<Item = Rectangle> {
let max_limit = AxisSize::unpack(self.axis(), max_limit);
let toplevels = toplevels
.iter()
.map(|t| LayoutToplevel {
preferred_size: AxisSize::unpack(self.axis(), t.preferred_size),
_phantom_data: PhantomData,
})
.collect::<Vec<_>>();
let toplevels = AliasableVec::from_unique(toplevels);
// Extend lifetime
let toplevels_slice = unsafe {
std::mem::transmute::<&[LayoutToplevel<'_, AxisSize>], &'a [LayoutToplevel<'a, AxisSize>]>(
&*toplevels,
)
};
let inner = self
.layout(max_limit, toplevels_slice)
.map(|rect| rect.pack(self.axis()));
AxisLayoutIterator {
inner,
_toplevels: toplevels,
}
}
}
struct AxisLayoutIterator<'a, I: Iterator<Item = Rectangle>> {
inner: I,
// After `inner` so it is dropped only after that is dropped
_toplevels: AliasableVec<LayoutToplevel<'a, AxisSize>>,
}
impl<I: Iterator<Item = Rectangle>> Iterator for AxisLayoutIterator<'_, I> {
type Item = Rectangle;
fn next(&mut self) -> Option<Rectangle> {
self.inner.next()
}
}