iris-aiandClaude Opus 5
97cc8b32ed
Fixed point cost 3x in layout: `many` went from 0.179 ms a frame to 0.544, and `scroll` from 0.011 to 0.030. The counters said why -- eight more "placed by redrawing" a frame -- and the reason was mine rather than the grid's. A retained drawing belongs to the layer it was made on, which `4e28f10` started enforcing, and `Stack` measures the child that sizes it by drawing it on its own layer and then draws it again on the child layer. So every stacked child redrew twice a frame, forever. `Painter::child_layer_at` addresses a child's layer rather than walking to it, and `Stack` measures on the layer that child ends up on. The second ask is then a reuse. Its glyphs are written once rather than once under the background and once over it. Measured on the same fixture: `scroll` 0.031 ms to 0.020, `many` 0.570 to 0.283, and the scroll phase's counters are back to what they were before fixed point -- 4 widget draws and 12 draw requests a frame, exactly. What is left above that baseline is not this. `ReuseOutcome` could not say "another layer" or "the region-node choice changed"; both returned without a counter, which is why the first look at this said nothing. They have counters now. Checked: fmt, clippy, 105 tests, five shrinker cases at 300 seeds, 100 generated seeds, and the examples byte-identical but for 36 pixels of `random` at one level -- edges that were being drawn twice. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
570 lines
22 KiB
Rust
570 lines
22 KiB
Rust
#[cfg(feature = "layout-diagnostics")]
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use crate::layout_diagnostics::{self as diag, Counter};
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use crate::{
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Axis, Holds, Len, Px, PxVec2, RegionAlign, Rel, RenderedText, Size, StrongWidget, TextAttrs,
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TextBuffer, TextData, TextureHandle, UiRegion, UiRenderState, UiRsc, UiScalar, UiVec2, Weight,
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WidgetId, Widgets,
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render::{
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GlyphPrimitive, Mask, MaskIdx, MoveIdx, Primitive, PrimitiveHandle, PrimitiveInst,
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PrimitiveKind, TexturePrimitive,
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},
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ui::render_state::DrawInfo,
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};
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const AXES: [Axis; 2] = [Axis::X, Axis::Y];
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/// makes your surfaces look pretty
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pub struct Painter<'a> {
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pub(super) state: &'a mut UiRenderState,
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pub(super) rsc: &'a mut dyn UiRsc,
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/// This widget's box, in the coordinates of `move_idx`.
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pub(super) region: UiRegion,
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pub(super) mask: MaskIdx,
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pub(super) textures: Vec<TextureHandle>,
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pub(super) primitives: Vec<PrimitiveHandle>,
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pub(super) children: Vec<WidgetId>,
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/// The children asked about so far, so the first box each was asked in
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/// is the one recorded as its offer.
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pub(super) offered: Vec<WidgetId>,
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/// The box this widget was first asked about in, in pixels.
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pub(super) offered_px: PxVec2,
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/// Whether this draw is in that box, which makes the questions it asks
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/// the ones a cold layout asks and their answers the ones to keep.
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pub(super) at_offer: bool,
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/// The children whose size this widget read while drawing.
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pub(super) size_deps: Vec<WidgetId>,
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/// What this draw itself read of its box in pixels, per axis: every
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/// length until it reads one, then that one, unless it says otherwise.
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pub(super) own: [Holds; 2],
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/// What the children it asked about and drew keep it to.
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pub(super) under: [Holds; 2],
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/// The movable region this widget's primitives are positioned through:
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/// its own when opted in, otherwise the nearest ancestor's.
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pub(super) move_idx: MoveIdx,
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pub layer: usize,
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/// The layer this widget was entered on, which its children's layers are
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/// counted from however far `layer` has walked.
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pub(super) own_layer: usize,
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pub(super) depth: usize,
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pub(super) id: WidgetId,
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}
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impl<'a> Painter<'a> {
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fn primitive_at<P: Primitive>(&mut self, primitive: P, region: UiRegion) {
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let kind = self.rsc.ui_mut().primitives.kind::<P>();
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self.write(kind, primitive, region);
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}
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/// Takes the kind, for a caller writing many of one primitive.
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fn write<P: Primitive>(&mut self, kind: PrimitiveKind<P>, primitive: P, region: UiRegion) {
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#[cfg(feature = "layout-diagnostics")]
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diag::bump(Counter::PrimitiveWrites);
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let h = self.state.layers.write(
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self.layer,
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PrimitiveInst {
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kind,
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id: self.id,
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primitive,
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region,
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mask_idx: self.mask,
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move_idx: self.move_idx,
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},
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);
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self.push_primitive(h);
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}
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fn push_primitive(&mut self, h: PrimitiveHandle) {
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if self.mask != MaskIdx::NONE {
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// TODO: I have no clue if this works at all :joy:
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self.rsc.ui_mut().masks.push_ref(self.mask);
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}
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self.primitives.push(h);
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}
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/// Writes a primitive to be rendered
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pub fn primitive(&mut self, primitive: impl PrimitiveLike) {
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let primitive = primitive.into_primitive(self);
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self.primitive_at(primitive, self.region)
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}
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pub fn primitive_within(&mut self, primitive: impl PrimitiveLike, region: UiRegion) {
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let primitive = primitive.into_primitive(self);
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self.primitive_at(primitive, region.within(&self.region));
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}
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pub fn set_mask(&mut self, region: UiRegion) {
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assert!(self.mask == MaskIdx::NONE);
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self.mask = self.rsc.ui_mut().masks.push(Mask {
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region,
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move_idx: self.move_idx,
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});
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}
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/// Draws a widget within this widget's region.
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pub fn widget<'s, W: ?Sized>(&'s mut self, id: &'s StrongWidget<W>) -> DrawResult<'s, 'a, W> {
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self.widget_within(id, UiRegion::FULL)
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}
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/// What a widget's rules declare its lengths to be, which whoever draws
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/// it resolves into its box. Reading them depends on nothing -- the box
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/// that comes of them is kept on the child, and `redraw` compares it
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/// there.
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fn declared_lens<W: ?Sized>(&self, id: &StrongWidget<W>) -> [Option<Len>; 2] {
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declared_lens(self.rsc.widgets(), id.id())
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}
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/// Takes back a child that was drawn only to find out how long it is.
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/// Its drawing is dropped and it is not one of this widget's children
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/// this frame; what it answered is still something this widget asked.
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pub fn undraw<W: ?Sized>(&mut self, id: &StrongWidget<W>) {
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self.children.retain(|child| *child != id.id());
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self.state.undraw_rec(id.id(), self.rsc);
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}
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/// Draws a widget somewhere within this one. `region` is in this widget's
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/// own coordinates, and the child's declared lengths are still to be
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/// taken from it. Where the child's drawing sits inside what it is given
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/// is the child's alignment, applied where the child is drawn, so a
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/// container positions a child either by handing it a box of exactly its
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/// length or by leaving it room and letting its alignment decide.
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pub fn widget_within<'s, W: ?Sized>(
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&'s mut self,
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id: &'s StrongWidget<W>,
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region: UiRegion,
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) -> DrawResult<'s, 'a, W> {
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self.widget_at(id, region, None)
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}
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/// Draws a widget with an alignment chosen by its container rather than
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/// the widget's property. Containers use this when the box they hand down
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/// already expresses the size they report around the child.
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pub fn widget_aligned<'s, W: ?Sized>(
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&'s mut self,
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id: &'s StrongWidget<W>,
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region: UiRegion,
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align: RegionAlign,
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) -> DrawResult<'s, 'a, W> {
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self.widget_at(id, region, Some(align))
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}
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fn widget_at<'s, W: ?Sized>(
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&'s mut self,
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id: &'s StrongWidget<W>,
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region: UiRegion,
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align_override: Option<RegionAlign>,
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) -> DrawResult<'s, 'a, W> {
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let region_node = self.rsc.widgets().is_region_node(id.id());
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let declared = self.declared_lens(id);
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let align = align_override.unwrap_or_else(|| self.rsc.widgets().alignment(id.id()));
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// Composing `FULL` through a box is not quite the identity in f32,
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// so a child with nothing declared keeps the box it would have had.
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let local = match declared.iter().any(Option::is_some) {
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true => declared_box(region, declared, align),
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false => region,
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};
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let within = match local == UiRegion::FULL {
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true => self.region,
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false => local.within(&self.region),
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};
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#[cfg(feature = "layout-diagnostics")]
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if region_node {
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diag::bump(Counter::RegionNodeDraws);
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diag::region_node(id.id(), self.id, within);
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}
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// A child listed twice would be moved twice.
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if !self.children.contains(&id.id()) {
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self.children.push(id.id());
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}
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let first_ask = self.offer(id.id());
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let offer = match first_ask {
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true => local,
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false => self.state.active.get(&id.id()).map_or(local, |a| a.offer),
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};
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let answers_offer = self.at_offer && local == offer;
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// The answer and what it holds for, both about the box asked in. The
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// child's record may say something else once its drawing has been
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// placed: a drawing made again in its placed box holds for that box.
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let (size, holds) = self.state.draw_inner(
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id.id(),
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within,
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DrawInfo {
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layer: self.layer,
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parent: Some(self.id),
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depth: self.depth + 1,
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parent_move: self.move_idx,
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region_node,
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mask: self.mask,
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offer,
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offered_px: self.px_within_offer(offer),
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align: align_override,
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},
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None,
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self.rsc,
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);
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if answers_offer {
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self.state.active.get_mut(&id.id()).unwrap().answer = (size, holds);
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}
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// Whatever the child's answer holds for keeps this one to the boxes
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// that give the child a length inside it.
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for (axis, under) in AXES.into_iter().zip(self.under.iter_mut()) {
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*under = under.and(holds[axis as usize].through(local.axis(axis).len()));
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}
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DrawResult {
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child: id,
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painter: self,
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size,
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}
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}
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/// What a child says its length is without being drawn, if it can say.
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/// Asking counts as reading its size.
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pub fn size_hint<W: ?Sized>(&mut self, id: &StrongWidget<W>, axis: Axis) -> Option<Len> {
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let widgets = self.rsc.widgets();
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// A rule is the answer where there is one: it wins over whatever the
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// widget would draw, so it has to win over what the widget says too.
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let hint = widgets.size_rules(id.id()).axis(axis).known().or_else(|| {
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widgets
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.get_dyn(id.id())
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.and_then(|widget| widget.size_hint(axis))
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});
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#[cfg(feature = "layout-diagnostics")]
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diag::hint_read(id.id(), self.id, axis, hint);
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match hint {
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Some(hint) => {
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#[cfg(feature = "layout-diagnostics")]
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diag::bump(Counter::HintHits);
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self.depend_on(id);
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Some(hint)
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}
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None => {
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#[cfg(feature = "layout-diagnostics")]
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diag::bump(Counter::HintMisses);
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None
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}
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}
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}
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/// A child's length in the box it is about to be offered, if it can be
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/// had without drawing it: from its hint, or from a drawing it already
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/// has that holds for that box.
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pub fn known_len<W: ?Sized>(
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&mut self,
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child: &StrongWidget<W>,
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axis: Axis,
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region: UiRegion,
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) -> Option<Len> {
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let declared = self.declared_lens(child);
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let align = self.rsc.widgets().alignment(child.id());
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let local = declared_box(region, declared, align);
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let within = local.within(&self.region);
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let first_ask = self.offer(child.id());
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if first_ask && let Some(active) = self.state.active.get_mut(&child.id()) {
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active.offer = local;
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}
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if let Some(hint) = self.size_hint(child, axis) {
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return Some(hint);
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}
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let px = self.state.px_of(self.move_idx, within);
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let (size, holds) =
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self.state
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.retained_size(child.id(), px, self.move_idx, self.rsc.widgets())?;
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#[cfg(feature = "layout-diagnostics")]
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diag::bump(Counter::RetainedSizeHits);
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self.depend_on(child);
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if first_ask {
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let active = self.state.active.get_mut(&child.id()).unwrap();
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active.answer = (size, holds);
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}
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for (axis, under) in AXES.into_iter().zip(self.under.iter_mut()) {
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*under = under.and(holds[axis as usize].through(local.axis(axis).len()));
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}
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Some(size.axis(axis))
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}
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/// Whether this is the first box a child is asked about in during a draw
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/// that is itself in the box it was asked in -- the question a cold
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/// layout asks, whose answer is the one to keep.
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fn offer(&mut self, child: WidgetId) -> bool {
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if !self.at_offer || self.offered.contains(&child) {
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return false;
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}
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self.offered.push(child);
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true
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}
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/// The pixel size of a part of the box this widget was asked in.
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fn px_within_offer(&self, local: UiRegion) -> PxVec2 {
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let size = local.size();
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PxVec2::new(
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size.x.to_px(self.offered_px.x),
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size.y.to_px(self.offered_px.y),
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)
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}
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fn depend_on<W: ?Sized>(&mut self, child: &StrongWidget<W>) {
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if !self.size_deps.contains(&child.id()) {
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self.size_deps.push(child.id());
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}
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}
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pub fn render_text<'b>(
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&mut self,
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buffer: &'b mut TextBuffer,
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attrs: &TextAttrs,
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width: Option<f32>,
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) -> &'b RenderedText {
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#[cfg(feature = "layout-diagnostics")]
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diag::render_text(self.id, self.rsc.widgets().label(self.id), width);
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let ui = self.rsc.ui_mut();
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ui.text.render(buffer, attrs, width)
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}
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// TODO: merge the text methods into the primitive ones.
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pub fn glyphs(&mut self, text: &RenderedText, origin: UiRegion) {
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let kind = self.rsc.ui_mut().primitives.kind::<GlyphPrimitive>();
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for glyph in text.glyphs.iter() {
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let mut region = origin;
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region.x.end = region.x.start;
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region.y.end = region.y.start;
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let mut region = region.offset(UiVec2::px(glyph.offset));
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region.x.end = region.x.start + UiScalar::px(glyph.entry.width as f32);
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region.y.end = region.y.start + UiScalar::px(glyph.entry.height as f32);
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self.write(
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kind,
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GlyphPrimitive {
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uv_min: glyph.entry.uv_min,
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uv_max: glyph.entry.uv_max,
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layer: glyph.entry.layer,
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color: text.color,
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flags: glyph.entry.flags(),
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},
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region,
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);
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}
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}
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/// This widget's box, in the coordinates its own primitives are written
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/// in -- so a region composed `within` it may be drawn directly.
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pub fn region(&self) -> UiRegion {
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self.region
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}
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/// Where this widget sits in a box longer than the length it takes. A
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/// widget that positions its own content reads it to place that content
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/// the way the box around it would have placed the widget.
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pub fn alignment(&self) -> RegionAlign {
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self.rsc.widgets().alignment(self.id)
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}
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/// Whether a rule beside this widget settles its length on `axis`, which
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/// makes whatever it reports for that axis moot. The widget under a rule
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/// does not otherwise learn of it -- this is for a container deciding
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/// whether reading its children across an axis is worth anything, since
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/// reading one is also what makes its own size depend on it.
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pub fn ruled(&self, axis: Axis) -> bool {
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self.rsc
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.widgets()
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.size_rules(self.id)
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.axis(axis)
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.known()
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.is_some()
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}
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/// The part of this widget's box that something of `size` takes, at the
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/// near edge. A container that reports one child's size gives every child
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/// this, so what it draws is inside what it says it occupies.
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pub fn box_of(&self, size: Size) -> UiRegion {
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placed_box(UiRegion::FULL, size, RegionAlign::NEAR, [None; 2])
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}
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/// This widget's box in pixels. Reading it makes the drawing one that
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/// holds for this box only, until `holds` says how far it goes.
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pub fn px_size(&mut self) -> PxVec2 {
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let px = self.state.px_of(self.move_idx, self.region);
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for (own, len) in self.own.iter_mut().zip([px.x, px.y]) {
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if *own == Holds::ANY {
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*own = Holds::at(len);
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}
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}
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px
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}
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/// One axis of this widget's box in pixels. Prefer this to
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/// [`Self::px_size`] when the other axis cannot affect the drawing.
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pub fn px_len(&mut self, axis: Axis) -> Px {
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let len = self.state.px_of(self.move_idx, self.region).axis(axis);
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let own = &mut self.own[axis as usize];
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if *own == Holds::ANY {
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*own = Holds::at(len);
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}
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len
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}
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/// The lengths of this widget's box on `axis` that what it is drawing
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/// holds for -- the same primitives, in the same fractions and offsets
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/// of the box, and the same reported size. A widget that read its
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/// length in pixels holds for that one alone until it says otherwise.
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pub fn holds(&mut self, axis: Axis, holds: impl Into<Holds>) {
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let holds = holds.into();
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debug_assert!(
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holds.contains(self.state.px_of(self.move_idx, self.region).axis(axis)),
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"'{}' ({:?}) says its drawing holds for lengths that leave out its own box",
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self.label(),
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self.id
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);
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self.own[axis as usize] = holds;
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}
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pub fn text_data(&mut self) -> &mut TextData {
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&mut self.rsc.ui_mut().text
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}
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pub fn child_layer(&mut self) {
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self.layer = self.state.layers.child(self.layer);
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}
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/// The layer this widget's `n`th child draws on, addressed rather than
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/// walked to. A container that measures one child by drawing it can ask
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/// on the layer that child will end up on, and then the second ask is a
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/// reuse rather than a second drawing on another layer.
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pub fn child_layer_at(&mut self, n: usize) {
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let mut at = self.state.layers.child(self.own_layer);
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for _ in 0..n {
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at = self.state.layers.next(at);
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}
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self.layer = at;
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}
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pub fn next_layer(&mut self) {
|
|
self.layer = self.state.layers.next(self.layer);
|
|
}
|
|
|
|
pub fn label(&self) -> &str {
|
|
&self.rsc.widgets().data(self.id).unwrap().label
|
|
}
|
|
|
|
pub fn id(&self) -> &WidgetId {
|
|
&self.id
|
|
}
|
|
}
|
|
|
|
/// A child that has just been drawn. Reading its size records that this
|
|
/// widget's own size depends on it; dropping it without reading draws the
|
|
/// child and leaves the parent independent of what it came to.
|
|
pub struct DrawResult<'p, 'a, W: ?Sized> {
|
|
painter: &'p mut Painter<'a>,
|
|
child: &'p StrongWidget<W>,
|
|
size: Size,
|
|
}
|
|
|
|
impl<W: ?Sized> DrawResult<'_, '_, W> {
|
|
pub fn size(self) -> Size {
|
|
#[cfg(feature = "layout-diagnostics")]
|
|
{
|
|
diag::bump(Counter::SizeReads);
|
|
diag::size_read(self.child.id(), self.painter.id, self.size);
|
|
}
|
|
self.painter.depend_on(self.child);
|
|
self.size
|
|
}
|
|
|
|
pub fn len(self, axis: Axis) -> Len {
|
|
self.size().axis(axis)
|
|
}
|
|
}
|
|
|
|
/// What `Painter::primitive` takes: a primitive, or something that yields one
|
|
/// and does whatever else drawing it needs.
|
|
pub trait PrimitiveLike {
|
|
type Primitive: Primitive;
|
|
fn into_primitive(self, painter: &mut Painter) -> Self::Primitive;
|
|
}
|
|
|
|
impl<P: Primitive> PrimitiveLike for P {
|
|
type Primitive = P;
|
|
fn into_primitive(self, _: &mut Painter) -> P {
|
|
self
|
|
}
|
|
}
|
|
|
|
impl PrimitiveLike for &TextureHandle {
|
|
type Primitive = TexturePrimitive;
|
|
|
|
/// Retains a share of the handle, so the slot the primitive names cannot
|
|
/// be freed and reused while it is still drawn.
|
|
fn into_primitive(self, painter: &mut Painter) -> TexturePrimitive {
|
|
painter.textures.push(self.clone());
|
|
self.into()
|
|
}
|
|
}
|
|
|
|
/// What a widget declares a length of its box to be. `leftover` is not one: a
|
|
/// share of what is left over is only a length to the widget dividing one,
|
|
/// so it passes up in the size instead.
|
|
pub(crate) fn declared_lens(widgets: &Widgets, id: WidgetId) -> [Option<Len>; 2] {
|
|
let rules = widgets.size_rules(id);
|
|
let widget = widgets.get_dyn(id);
|
|
AXES.map(|axis| {
|
|
rules.axis(axis).declared().or_else(|| {
|
|
// A hint still narrows the box where no rule does, which is how a
|
|
// widget with a natural pixel size -- an image, a gap -- gets that
|
|
// size rather than the whole offer. That is the offer's business
|
|
// rather than a declaration's, and this falls away once a widget
|
|
// occupies its reported size inside the box it was offered.
|
|
widget
|
|
.and_then(|widget| widget.size_hint(axis))
|
|
.filter(|len| len.leftover == Weight::ZERO)
|
|
})
|
|
})
|
|
}
|
|
|
|
/// The box a drawing occupies: the size the widget reported, on the side of
|
|
/// the box it was asked in that its alignment says. An axis reported as a
|
|
/// share fills, because a share is a length only to whoever divides one, and
|
|
/// whoever did is the one that handed down this box. A declared axis is
|
|
/// left alone too: `declared_box` already placed it, in the parent's box,
|
|
/// and the rule's length is what the widget reports there.
|
|
///
|
|
/// A reported fraction is a fraction of the box the widget drew in, where a
|
|
/// declared one is a fraction of the box its parent handed down -- a span
|
|
/// reporting `rel(1.0)` means all of what it was given, whatever that was a
|
|
/// fraction of. So this scales by the box rather than composing into it.
|
|
pub(crate) fn placed_box(
|
|
region: UiRegion,
|
|
size: Size,
|
|
align: RegionAlign,
|
|
declared: [Option<Len>; 2],
|
|
) -> UiRegion {
|
|
let mut placed = region;
|
|
for (axis, declared) in AXES.into_iter().zip(declared) {
|
|
let reported = size.axis(axis);
|
|
if reported.leftover != Weight::ZERO || declared.is_some() {
|
|
continue;
|
|
}
|
|
let span = placed.axis_mut(axis);
|
|
let len = span.len().scale(reported.rel) + UiScalar::from_parts(Rel::ZERO, reported.px);
|
|
span.start += (span.len() - len).scale(align.axis(axis).rel());
|
|
span.end = span.start + len;
|
|
}
|
|
placed
|
|
}
|
|
|
|
/// Takes a widget's declared lengths in the box `region` is given in, since a
|
|
/// fraction of a length means a fraction of that one, and puts what is left
|
|
/// over on the side its alignment says. A caller that already reserved the
|
|
/// space hands back the same length, so this is the identity for it.
|
|
pub(crate) fn declared_box(
|
|
mut region: UiRegion,
|
|
declared: [Option<Len>; 2],
|
|
align: RegionAlign,
|
|
) -> UiRegion {
|
|
for (axis, len) in AXES.into_iter().zip(declared) {
|
|
let Some(len) = len else { continue };
|
|
let span = region.axis_mut(axis);
|
|
let len = UiScalar::from_parts(len.rel, len.px);
|
|
span.start += (span.len() - len).scale(align.axis(axis).rel());
|
|
span.end = span.start + len;
|
|
}
|
|
region
|
|
}
|