Files
iris/src/core/position/span.rs
2025-11-13 16:59:31 -05:00

117 lines
3.3 KiB
Rust

use std::marker::PhantomData;
use crate::prelude::*;
pub struct Span {
pub children: Vec<WidgetId>,
pub dir: Dir,
pub gap: f32,
}
impl Widget for Span {
fn draw(&mut self, painter: &mut Painter) {
let total = self.len_sum(&mut painter.size_ctx());
let mut start = UiScalar::rel_min();
for child in &self.children {
let mut child_region = UiRegion::full();
let mut axis = child_region.axis_mut(self.dir.axis);
axis.top_left.set(start);
let len = painter.size(child).axis(self.dir.axis);
if len.rest > 0.0 {
let offset = UiScalar::new(total.rel, total.abs);
let rel_end = UiScalar::from_anchor(len.rest / total.rest);
start = rel_end.within(start, (UiScalar::rel_max() + start) - offset);
}
start.abs += len.abs;
start.rel += len.rel;
axis.bot_right.set(start);
if self.dir.sign == Sign::Neg {
child_region.flip(self.dir.axis);
}
painter.widget_within(child, child_region);
start.abs += self.gap;
}
}
fn desired_size(&mut self, ctx: &mut SizeCtx) -> Size {
let mut sums = self.len_sum(ctx);
let dir_len = if sums.rest == 0.0 && sums.rel == 0.0 {
sums.abs += self.gap * self.children.len().saturating_sub(1) as f32;
sums
} else {
Len::default()
};
let mut max_ortho = Len::ZERO;
for child in &self.children {
let len = ctx.size(child).axis(!self.dir.axis);
// TODO: rel shouldn't do this, but no easy way before actually calculating pixels
if len.rel > 0.0 || len.rest > 0.0 {
max_ortho.rest = 1.0;
max_ortho.abs = 0.0;
break;
}
max_ortho.abs = max_ortho.abs.max(len.abs);
}
Size::from_axis(self.dir.axis, dir_len, max_ortho)
}
}
impl Span {
pub fn empty(dir: Dir) -> Self {
Self {
children: Vec::new(),
dir,
gap: 0.0,
}
}
pub fn gap(mut self, gap: impl UiNum) -> Self {
self.gap = gap.to_f32();
self
}
fn len_sum(&mut self, ctx: &mut SizeCtx) -> Len {
self.children.iter_mut().fold(Len::ZERO, |mut s, id| {
s += ctx.size(id).axis(self.dir.axis);
s
})
}
}
pub struct SpanBuilder<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> {
pub children: Wa,
pub dir: Dir,
pub gap: f32,
_pd: PhantomData<Tag>,
}
impl<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> FnOnce<(&mut Ui,)>
for SpanBuilder<LEN, Wa, Tag>
{
type Output = Span;
extern "rust-call" fn call_once(self, args: (&mut Ui,)) -> Self::Output {
Span {
children: self.children.ui(args.0).arr.to_vec(),
dir: self.dir,
gap: self.gap,
}
}
}
impl<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> SpanBuilder<LEN, Wa, Tag> {
pub fn new(children: Wa, dir: Dir) -> Self {
Self {
children,
dir,
gap: 0.0,
_pd: PhantomData,
}
}
pub fn gap(mut self, gap: impl UiNum) -> Self {
self.gap = gap.to_f32();
self
}
}