typst/src/layout/pad.rs

48 lines
1.3 KiB
Rust

use super::*;
use crate::geom::Linear;
/// A node that pads its child at the sides.
#[derive(Debug, Clone, PartialEq)]
pub struct Pad {
/// The amount of padding.
pub padding: Sides<Linear>,
/// The child node whose sides to pad.
pub child: LayoutNode,
}
impl Layout for Pad {
fn layout(&self, ctx: &mut LayoutContext, areas: &Areas) -> Vec<Layouted> {
let shrink = |size| size - self.padding.eval(size).size();
let areas = Areas {
current: Area {
rem: shrink(areas.current.rem),
full: shrink(areas.current.full),
},
backlog: areas.backlog.iter().copied().map(shrink).collect(),
last: areas.last.map(shrink),
};
let mut layouted = self.child.layout(ctx, &areas);
for item in &mut layouted {
if let Layouted::Boxed(boxed, _) = item {
let padding = self.padding.eval(boxed.size);
let origin = Point::new(padding.left, padding.top);
boxed.size += padding.size();
for (point, _) in &mut boxed.elements {
*point += origin;
}
}
}
layouted
}
}
impl From<Pad> for LayoutNode {
fn from(pad: Pad) -> Self {
Self::dynamic(pad)
}
}