Files
ai-app/iris/src/widget/position/offset.rs
T
irisandClaude Sonnet 1a6599e1b2 iris: Widget::draw reports the size it used, replacing desired_width/height
Implements LAYOUT.md end to end: one fn draw(&mut self, &mut Painter) ->
Size replaces draw + desired_width/desired_height on every widget in
iris/src/widget/, SizeCtx and Cache are deleted, and a moved widget
(Scroll, Offset) costs one move_offsets write resolved by a shared
resolve_move WGSL function in both shader stages -- O(1) regardless of
how many primitives are in its subtree, measured at 500 in the new
iris/src/layout_tests.rs (a plain unit test: UiRenderState touches no
GPU or window).

Five real bugs surfaced only by diffing iris/run-headless.sh screenshots
against the pre-change tree and are written up in LAYOUT.md's
"Deviations found during implementation": Aligned's provisional draw
composing painter.region() a second time through widget_within; Sized/
MaxSize reporting a capped size while still painting their child
unconstrained (fine under the old two-pass model, wrong once a parent
like Aligned draws before knowing the final size); a widget's
move_offsets parent link being unreadable from self.active while its
own ActiveData is still mid-construction; Painter::reposition needing
the child's *painted* footprint (its reported size, top-left anchored)
rather than its offered region; and a widget's move slot needing to be
reused in place across redraws, with its delta reset, rather than
reallocated.

All four iris/examples render pixel-identical to the pre-change tree.
cargo fmt/clippy/test clean across the workspace (18 tests: 14
pre-existing plus 4 new).

Co-Authored-By: Claude Sonnet <noreply@anthropic.com>
2026-09-04 23:40:56 -04:00

14 lines
291 B
Rust

use crate::prelude::*;
pub struct Offset {
pub inner: StrongWidget,
pub amt: UiVec2,
}
impl Widget for Offset {
fn draw(&mut self, painter: &mut Painter) -> Size {
let region = UiRegion::FULL.offset(self.amt);
painter.widget_within(&self.inner, region)
}
}