Upgrade to Taffy 0.4 (#10690)

# Objective

- Enables support for `Display::Block`
- Enables support for `Overflow::Hidden`
- Allows for cleaner integration with text, image and other content
layout.
- Unblocks https://github.com/bevyengine/bevy/pull/8104
- Unlocks the possibility of Bevy creating a custom layout tree over
which Taffy operates.
- Enables #8808 / #10193 to remove a Mutex around the font system.

## Todo

- [x] ~Fix rendering of text/images to account for padding/border on
nodes (should size/position to content box rather than border box)~ In
order get this into a mergeable state this PR instead zeroes out
padding/border when syncing leaf node styles into Taffy to preserve the
existing behaviour. https://github.com/bevyengine/bevy/issues/6879 can
be fixed in a followup PR.

## Solution

- Update the version of Taffy
- Update code to work with the new version

Note: Taffy 0.4 has not yet been released. This PR is being created in
advance of the release to ensure that there are no blockers to upgrading
once the release occurs.

---

## Changelog

- Bevy now supports the `Display::Block` and `Overflow::Hidden` styles.
This commit is contained in:
Nico Burns 2024-05-01 02:13:17 +12:00 committed by GitHub
parent 9973f0c8a3
commit 96b9d0a7e2
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
10 changed files with 250 additions and 123 deletions

View file

@ -31,7 +31,7 @@ bevy_window = { path = "../bevy_window", version = "0.14.0-dev" }
bevy_utils = { path = "../bevy_utils", version = "0.14.0-dev" }
# other
taffy = { version = "0.3.10" }
taffy = { version = "0.4" }
serde = { version = "1", features = ["derive"], optional = true }
bytemuck = { version = "1.5", features = ["derive"] }
thiserror = "1.0.0"

View file

@ -3,8 +3,8 @@ use taffy::style_helpers;
use crate::{
AlignContent, AlignItems, AlignSelf, Display, FlexDirection, FlexWrap, GridAutoFlow,
GridPlacement, GridTrack, GridTrackRepetition, JustifyContent, JustifyItems, JustifySelf,
MaxTrackSizingFunction, MinTrackSizingFunction, PositionType, RepeatedGridTrack, Style, UiRect,
Val,
MaxTrackSizingFunction, MinTrackSizingFunction, OverflowAxis, PositionType, RepeatedGridTrack,
Style, UiRect, Val,
};
use super::LayoutContext;
@ -18,31 +18,31 @@ impl Val {
Val::Auto => taffy::style::LengthPercentageAuto::Auto,
Val::Percent(value) => taffy::style::LengthPercentageAuto::Percent(value / 100.),
Val::Px(value) => {
taffy::style::LengthPercentageAuto::Points(context.scale_factor * value)
taffy::style::LengthPercentageAuto::Length(context.scale_factor * value)
}
Val::VMin(value) => {
taffy::style::LengthPercentageAuto::Points(context.min_size * value / 100.)
taffy::style::LengthPercentageAuto::Length(context.min_size * value / 100.)
}
Val::VMax(value) => {
taffy::style::LengthPercentageAuto::Points(context.max_size * value / 100.)
taffy::style::LengthPercentageAuto::Length(context.max_size * value / 100.)
}
Val::Vw(value) => {
taffy::style::LengthPercentageAuto::Points(context.physical_size.x * value / 100.)
taffy::style::LengthPercentageAuto::Length(context.physical_size.x * value / 100.)
}
Val::Vh(value) => {
taffy::style::LengthPercentageAuto::Points(context.physical_size.y * value / 100.)
taffy::style::LengthPercentageAuto::Length(context.physical_size.y * value / 100.)
}
}
}
fn into_length_percentage(self, context: &LayoutContext) -> taffy::style::LengthPercentage {
match self.into_length_percentage_auto(context) {
taffy::style::LengthPercentageAuto::Auto => taffy::style::LengthPercentage::Points(0.0),
taffy::style::LengthPercentageAuto::Auto => taffy::style::LengthPercentage::Length(0.0),
taffy::style::LengthPercentageAuto::Percent(value) => {
taffy::style::LengthPercentage::Percent(value)
}
taffy::style::LengthPercentageAuto::Points(value) => {
taffy::style::LengthPercentage::Points(value)
taffy::style::LengthPercentageAuto::Length(value) => {
taffy::style::LengthPercentage::Length(value)
}
}
}
@ -63,9 +63,18 @@ impl UiRect {
}
}
pub fn from_style(context: &LayoutContext, style: &Style) -> taffy::style::Style {
pub fn from_style(
context: &LayoutContext,
style: &Style,
ignore_padding_and_border: bool,
) -> taffy::style::Style {
taffy::style::Style {
display: style.display.into(),
overflow: taffy::Point {
x: style.overflow.x.into(),
y: style.overflow.y.into(),
},
scrollbar_width: 0.0,
position: style.position_type.into(),
flex_direction: style.flex_direction.into(),
flex_wrap: style.flex_wrap.into(),
@ -75,7 +84,7 @@ pub fn from_style(context: &LayoutContext, style: &Style) -> taffy::style::Style
justify_self: style.justify_self.into(),
align_content: style.align_content.into(),
justify_content: style.justify_content.into(),
inset: taffy::prelude::Rect {
inset: taffy::Rect {
left: style.left.into_length_percentage_auto(context),
right: style.right.into_length_percentage_auto(context),
top: style.top.into_length_percentage_auto(context),
@ -84,29 +93,41 @@ pub fn from_style(context: &LayoutContext, style: &Style) -> taffy::style::Style
margin: style
.margin
.map_to_taffy_rect(|m| m.into_length_percentage_auto(context)),
padding: style
// Ignore padding for leaf nodes as it isn't implemented in the rendering engine.
// TODO: Implement rendering of padding for leaf nodes
padding: if ignore_padding_and_border {
taffy::Rect::zero()
} else {
style
.padding
.map_to_taffy_rect(|m| m.into_length_percentage(context)),
border: style
.map_to_taffy_rect(|m| m.into_length_percentage(context))
},
// Ignore border for leaf nodes as it isn't implemented in the rendering engine.
// TODO: Implement rendering of border for leaf nodes
border: if ignore_padding_and_border {
taffy::Rect::zero()
} else {
style
.border
.map_to_taffy_rect(|m| m.into_length_percentage(context)),
.map_to_taffy_rect(|m| m.into_length_percentage(context))
},
flex_grow: style.flex_grow,
flex_shrink: style.flex_shrink,
flex_basis: style.flex_basis.into_dimension(context),
size: taffy::prelude::Size {
size: taffy::Size {
width: style.width.into_dimension(context),
height: style.height.into_dimension(context),
},
min_size: taffy::prelude::Size {
min_size: taffy::Size {
width: style.min_width.into_dimension(context),
height: style.min_height.into_dimension(context),
},
max_size: taffy::prelude::Size {
max_size: taffy::Size {
width: style.max_width.into_dimension(context),
height: style.max_height.into_dimension(context),
},
aspect_ratio: style.aspect_ratio,
gap: taffy::prelude::Size {
gap: taffy::Size {
width: style.column_gap.into_length_percentage(context),
height: style.row_gap.into_length_percentage(context),
},
@ -231,11 +252,22 @@ impl From<Display> for taffy::style::Display {
match value {
Display::Flex => taffy::style::Display::Flex,
Display::Grid => taffy::style::Display::Grid,
Display::Block => taffy::style::Display::Block,
Display::None => taffy::style::Display::None,
}
}
}
impl From<OverflowAxis> for taffy::style::Overflow {
fn from(value: OverflowAxis) -> Self {
match value {
OverflowAxis::Visible => taffy::style::Overflow::Visible,
OverflowAxis::Clip => taffy::style::Overflow::Clip,
OverflowAxis::Hidden => taffy::style::Overflow::Hidden,
}
}
}
impl From<FlexDirection> for taffy::style::FlexDirection {
fn from(value: FlexDirection) -> Self {
match value {
@ -489,7 +521,7 @@ mod tests {
grid_row: GridPlacement::span(3),
};
let viewport_values = LayoutContext::new(1.0, bevy_math::Vec2::new(800., 600.));
let taffy_style = from_style(&viewport_values, &bevy_style);
let taffy_style = from_style(&viewport_values, &bevy_style, false);
assert_eq!(taffy_style.display, taffy::style::Display::Flex);
assert_eq!(taffy_style.position, taffy::style::Position::Absolute);
assert_eq!(
@ -502,7 +534,7 @@ mod tests {
);
assert_eq!(
taffy_style.inset.top,
taffy::style::LengthPercentageAuto::Points(12.)
taffy::style::LengthPercentageAuto::Length(12.)
);
assert_eq!(
taffy_style.inset.bottom,
@ -537,7 +569,7 @@ mod tests {
);
assert_eq!(
taffy_style.margin.right,
taffy::style::LengthPercentageAuto::Points(10.)
taffy::style::LengthPercentageAuto::Length(10.)
);
assert_eq!(
taffy_style.margin.top,
@ -553,7 +585,7 @@ mod tests {
);
assert_eq!(
taffy_style.padding.right,
taffy::style::LengthPercentage::Points(21.)
taffy::style::LengthPercentage::Length(21.)
);
assert_eq!(
taffy_style.padding.top,
@ -565,7 +597,7 @@ mod tests {
);
assert_eq!(
taffy_style.border.left,
taffy::style::LengthPercentage::Points(14.)
taffy::style::LengthPercentage::Length(14.)
);
assert_eq!(
taffy_style.border.right,
@ -594,18 +626,18 @@ mod tests {
);
assert_eq!(
taffy_style.grid_template_rows,
vec![sh::points(10.0), sh::percent(0.5), sh::fr(1.0)]
vec![sh::length(10.0), sh::percent(0.5), sh::fr(1.0)]
);
assert_eq!(
taffy_style.grid_template_columns,
vec![sh::repeat(5, vec![sh::points(10.0)])]
vec![sh::repeat(5, vec![sh::length(10.0)])]
);
assert_eq!(
taffy_style.grid_auto_rows,
vec![
sh::fit_content(taffy::style::LengthPercentage::Points(10.0)),
sh::fit_content(taffy::style::LengthPercentage::Length(10.0)),
sh::fit_content(taffy::style::LengthPercentage::Percent(0.25)),
sh::minmax(sh::points(0.0), sh::fr(2.0)),
sh::minmax(sh::length(0.0), sh::fr(2.0)),
]
);
assert_eq!(
@ -627,17 +659,17 @@ mod tests {
use taffy::style::LengthPercentage;
let context = LayoutContext::new(2.0, bevy_math::Vec2::new(800., 600.));
let cases = [
(Val::Auto, LengthPercentage::Points(0.)),
(Val::Auto, LengthPercentage::Length(0.)),
(Val::Percent(1.), LengthPercentage::Percent(0.01)),
(Val::Px(1.), LengthPercentage::Points(2.)),
(Val::Vw(1.), LengthPercentage::Points(8.)),
(Val::Vh(1.), LengthPercentage::Points(6.)),
(Val::VMin(2.), LengthPercentage::Points(12.)),
(Val::VMax(2.), LengthPercentage::Points(16.)),
(Val::Px(1.), LengthPercentage::Length(2.)),
(Val::Vw(1.), LengthPercentage::Length(8.)),
(Val::Vh(1.), LengthPercentage::Length(6.)),
(Val::VMin(2.), LengthPercentage::Length(12.)),
(Val::VMax(2.), LengthPercentage::Length(16.)),
];
for (val, length) in cases {
assert!(match (val.into_length_percentage(&context), length) {
(LengthPercentage::Points(a), LengthPercentage::Points(b))
(LengthPercentage::Length(a), LengthPercentage::Length(b))
| (LengthPercentage::Percent(a), LengthPercentage::Percent(b)) =>
(a - b).abs() < 0.0001,
_ => false,

View file

@ -1,7 +1,6 @@
use std::fmt::Write;
use taffy::prelude::Node;
use taffy::tree::LayoutTree;
use taffy::{NodeId, TraversePartialTree};
use bevy_ecs::prelude::Entity;
use bevy_utils::HashMap;
@ -10,7 +9,7 @@ use crate::layout::ui_surface::UiSurface;
/// Prints a debug representation of the computed layout of the UI layout tree for each window.
pub fn print_ui_layout_tree(ui_surface: &UiSurface) {
let taffy_to_entity: HashMap<Node, Entity> = ui_surface
let taffy_to_entity: HashMap<NodeId, Entity> = ui_surface
.entity_to_taffy
.iter()
.map(|(entity, node)| (*node, *entity))
@ -35,9 +34,9 @@ pub fn print_ui_layout_tree(ui_surface: &UiSurface) {
/// Recursively navigates the layout tree printing each node's information.
fn print_node(
ui_surface: &UiSurface,
taffy_to_entity: &HashMap<Node, Entity>,
taffy_to_entity: &HashMap<NodeId, Entity>,
entity: Entity,
node: Node,
node: NodeId,
has_sibling: bool,
lines_string: String,
acc: &mut String,
@ -46,13 +45,14 @@ fn print_node(
let layout = tree.layout(node).unwrap();
let style = tree.style(node).unwrap();
let num_children = tree.child_count(node).unwrap();
let num_children = tree.child_count(node);
let display_variant = match (num_children, style.display) {
(_, taffy::style::Display::None) => "NONE",
(0, _) => "LEAF",
(_, taffy::style::Display::Flex) => "FLEX",
(_, taffy::style::Display::Grid) => "GRID",
(_, taffy::style::Display::Block) => "BLOCK",
};
let fork_string = if has_sibling {
@ -70,7 +70,7 @@ fn print_node(
y = layout.location.y,
width = layout.size.width,
height = layout.size.height,
measured = if tree.needs_measure(node) { "measured" } else { "" }
measured = if tree.get_node_context(node).is_some() { "measured" } else { "" }
).ok();
let bar = if has_sibling { "" } else { " " };
let new_string = lines_string + bar;

View file

@ -1,5 +1,6 @@
use thiserror::Error;
use crate::{ContentSize, DefaultUiCamera, Node, Outline, Style, TargetCamera, UiScale};
use bevy_ecs::{
change_detection::{DetectChanges, DetectChangesMut},
entity::Entity,
@ -18,8 +19,6 @@ use bevy_utils::{HashMap, HashSet};
use bevy_window::{PrimaryWindow, Window, WindowScaleFactorChanged};
use ui_surface::UiSurface;
use crate::{ContentSize, DefaultUiCamera, Node, Outline, Style, TargetCamera, UiScale};
mod convert;
pub mod debug;
pub(crate) mod ui_surface;
@ -60,7 +59,7 @@ pub enum LayoutError {
#[error("Invalid hierarchy")]
InvalidHierarchy,
#[error("Taffy error: {0}")]
TaffyError(#[from] taffy::error::TaffyError),
TaffyError(#[from] taffy::TaffyError),
}
#[derive(SystemParam)]
@ -82,8 +81,15 @@ pub fn ui_layout_system(
mut resize_events: EventReader<bevy_window::WindowResized>,
mut ui_surface: ResMut<UiSurface>,
root_node_query: Query<(Entity, Option<&TargetCamera>), (With<Node>, Without<Parent>)>,
style_query: Query<(Entity, Ref<Style>, Option<&TargetCamera>), With<Node>>,
mut measure_query: Query<(Entity, &mut ContentSize)>,
mut style_query: Query<
(
Entity,
Ref<Style>,
Option<&mut ContentSize>,
Option<&TargetCamera>,
),
With<Node>,
>,
children_query: Query<(Entity, Ref<Children>), With<Node>>,
just_children_query: Query<&Children>,
mut removed_components: UiLayoutSystemRemovedComponentParam,
@ -152,8 +158,13 @@ pub fn ui_layout_system(
}
}
// Resize all nodes
for (entity, style, target_camera) in style_query.iter() {
// When a `ContentSize` component is removed from an entity, we need to remove the measure from the corresponding taffy node.
for entity in removed_components.removed_content_sizes.read() {
ui_surface.try_remove_node_context(entity);
}
// Sync Style and ContentSize to Taffy for all nodes
for (entity, style, content_size, target_camera) in style_query.iter_mut() {
if let Some(camera) =
camera_with_default(target_camera).and_then(|c| camera_layout_info.get(&c))
{
@ -161,29 +172,24 @@ pub fn ui_layout_system(
|| !scale_factor_events.is_empty()
|| ui_scale.is_changed()
|| style.is_changed()
|| content_size
.as_ref()
.map(|c| c.measure.is_some())
.unwrap_or(false)
{
let layout_context = LayoutContext::new(
camera.scale_factor,
[camera.size.x as f32, camera.size.y as f32].into(),
);
ui_surface.upsert_node(entity, &style, &layout_context);
let measure = content_size.and_then(|mut c| c.measure.take());
ui_surface.upsert_node(&layout_context, entity, &style, measure);
}
} else {
ui_surface.upsert_node(entity, &Style::default(), &LayoutContext::default());
ui_surface.upsert_node(&LayoutContext::DEFAULT, entity, &Style::default(), None);
}
}
scale_factor_events.clear();
// When a `ContentSize` component is removed from an entity, we need to remove the measure from the corresponding taffy node.
for entity in removed_components.removed_content_sizes.read() {
ui_surface.try_remove_measure(entity);
}
for (entity, mut content_size) in &mut measure_query {
if let Some(measure_func) = content_size.measure_func.take() {
ui_surface.try_update_measure(entity, measure_func);
}
}
// clean up removed nodes
ui_surface.remove_entities(removed_components.removed_nodes.read());
@ -337,7 +343,7 @@ fn round_layout_coords(value: Vec2) -> Vec2 {
#[cfg(test)]
mod tests {
use taffy::tree::LayoutTree;
use taffy::TraversePartialTree;
use bevy_asset::AssetEvent;
use bevy_asset::Assets;
@ -578,7 +584,7 @@ mod tests {
let ui_parent_node = ui_surface.entity_to_taffy[&ui_parent_entity];
// `ui_parent_node` shouldn't have any children yet
assert_eq!(ui_surface.taffy.child_count(ui_parent_node).unwrap(), 0);
assert_eq!(ui_surface.taffy.child_count(ui_parent_node), 0);
let mut ui_child_entities = (0..10)
.map(|_| {
@ -597,7 +603,7 @@ mod tests {
1 + ui_child_entities.len()
);
assert_eq!(
ui_surface.taffy.child_count(ui_parent_node).unwrap(),
ui_surface.taffy.child_count(ui_parent_node),
ui_child_entities.len()
);
@ -628,7 +634,7 @@ mod tests {
1 + ui_child_entities.len()
);
assert_eq!(
ui_surface.taffy.child_count(ui_parent_node).unwrap(),
ui_surface.taffy.child_count(ui_parent_node),
ui_child_entities.len()
);
@ -941,8 +947,8 @@ mod tests {
let ui_surface = world.resource::<UiSurface>();
let ui_node = ui_surface.entity_to_taffy[&ui_entity];
// a node with a content size needs to be measured
assert!(ui_surface.taffy.needs_measure(ui_node));
// a node with a content size should have taffy context
assert!(ui_surface.taffy.get_node_context(ui_node).is_some());
let layout = ui_surface.get_layout(ui_entity).unwrap();
assert_eq!(layout.size.width, content_size.x);
assert_eq!(layout.size.height, content_size.y);
@ -952,8 +958,8 @@ mod tests {
ui_schedule.run(&mut world);
let ui_surface = world.resource::<UiSurface>();
// a node without a content size does not need to be measured
assert!(!ui_surface.taffy.needs_measure(ui_node));
// a node without a content size should not have taffy context
assert!(ui_surface.taffy.get_node_context(ui_node).is_none());
// Without a content size, the node has no width or height constraints so the length of both dimensions is 0.
let layout = ui_surface.get_layout(ui_entity).unwrap();

View file

@ -1,7 +1,6 @@
use std::fmt;
use taffy::prelude::LayoutTree;
use taffy::Taffy;
use taffy::TaffyTree;
use bevy_ecs::entity::{Entity, EntityHashMap};
use bevy_ecs::prelude::Resource;
@ -11,28 +10,28 @@ use bevy_utils::default;
use bevy_utils::tracing::warn;
use crate::layout::convert;
use crate::{LayoutContext, LayoutError, Style};
use crate::{LayoutContext, LayoutError, Measure, NodeMeasure, Style};
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct RootNodePair {
// The implicit "viewport" node created by Bevy
pub(super) implicit_viewport_node: taffy::node::Node,
pub(super) implicit_viewport_node: taffy::NodeId,
// The root (parentless) node specified by the user
pub(super) user_root_node: taffy::node::Node,
pub(super) user_root_node: taffy::NodeId,
}
#[derive(Resource)]
pub struct UiSurface {
pub(super) entity_to_taffy: EntityHashMap<taffy::node::Node>,
pub(super) camera_entity_to_taffy: EntityHashMap<EntityHashMap<taffy::node::Node>>,
pub(super) entity_to_taffy: EntityHashMap<taffy::NodeId>,
pub(super) camera_entity_to_taffy: EntityHashMap<EntityHashMap<taffy::NodeId>>,
pub(super) camera_roots: EntityHashMap<Vec<RootNodePair>>,
pub(super) taffy: Taffy,
pub(super) taffy: TaffyTree<NodeMeasure>,
}
fn _assert_send_sync_ui_surface_impl_safe() {
fn _assert_send_sync<T: Send + Sync>() {}
_assert_send_sync::<EntityHashMap<taffy::node::Node>>();
_assert_send_sync::<Taffy>();
_assert_send_sync::<EntityHashMap<taffy::NodeId>>();
_assert_send_sync::<TaffyTree<NodeMeasure>>();
_assert_send_sync::<UiSurface>();
}
@ -47,7 +46,7 @@ impl fmt::Debug for UiSurface {
impl Default for UiSurface {
fn default() -> Self {
let mut taffy = Taffy::new();
let mut taffy: TaffyTree<NodeMeasure> = TaffyTree::new();
taffy.disable_rounding();
Self {
entity_to_taffy: Default::default(),
@ -61,30 +60,55 @@ impl Default for UiSurface {
impl UiSurface {
/// Retrieves the Taffy node associated with the given UI node entity and updates its style.
/// If no associated Taffy node exists a new Taffy node is inserted into the Taffy layout.
pub fn upsert_node(&mut self, entity: Entity, style: &Style, context: &LayoutContext) {
let mut added = false;
pub fn upsert_node(
&mut self,
layout_context: &LayoutContext,
entity: Entity,
style: &Style,
mut new_node_context: Option<NodeMeasure>,
) {
let taffy = &mut self.taffy;
let taffy_node = self.entity_to_taffy.entry(entity).or_insert_with(|| {
let mut added = false;
let taffy_node_id = *self.entity_to_taffy.entry(entity).or_insert_with(|| {
added = true;
taffy.new_leaf(convert::from_style(context, style)).unwrap()
if let Some(measure) = new_node_context.take() {
taffy
.new_leaf_with_context(
convert::from_style(layout_context, style, true),
measure,
)
.unwrap()
} else {
taffy
.new_leaf(convert::from_style(layout_context, style, false))
.unwrap()
}
});
if !added {
self.taffy
.set_style(*taffy_node, convert::from_style(context, style))
let has_measure = if new_node_context.is_some() {
taffy
.set_node_context(taffy_node_id, new_node_context)
.unwrap();
true
} else {
taffy.get_node_context(taffy_node_id).is_some()
};
taffy
.set_style(
taffy_node_id,
convert::from_style(layout_context, style, has_measure),
)
.unwrap();
}
}
/// Update the `MeasureFunc` of the taffy node corresponding to the given [`Entity`] if the node exists.
pub fn try_update_measure(
&mut self,
entity: Entity,
measure_func: taffy::node::MeasureFunc,
) -> Option<()> {
pub fn update_node_context(&mut self, entity: Entity, context: NodeMeasure) -> Option<()> {
let taffy_node = self.entity_to_taffy.get(&entity)?;
self.taffy.set_measure(*taffy_node, Some(measure_func)).ok()
self.taffy.set_node_context(*taffy_node, Some(context)).ok()
}
/// Update the children of the taffy node corresponding to the given [`Entity`].
@ -115,9 +139,9 @@ without UI components as a child of an entity with UI components, results may be
}
/// Removes the measure from the entity's taffy node if it exists. Does nothing otherwise.
pub fn try_remove_measure(&mut self, entity: Entity) {
pub fn try_remove_node_context(&mut self, entity: Entity) {
if let Some(taffy_node) = self.entity_to_taffy.get(&entity) {
self.taffy.set_measure(*taffy_node, None).unwrap();
self.taffy.set_node_context(*taffy_node, None).unwrap();
}
}
@ -183,7 +207,30 @@ without UI components as a child of an entity with UI components, results may be
};
for root_nodes in camera_root_nodes {
self.taffy
.compute_layout(root_nodes.implicit_viewport_node, available_space)
.compute_layout_with_measure(
root_nodes.implicit_viewport_node,
available_space,
|known_dimensions: taffy::Size<Option<f32>>,
available_space: taffy::Size<taffy::AvailableSpace>,
_node_id: taffy::NodeId,
context: Option<&mut NodeMeasure>|
-> taffy::Size<f32> {
context
.map(|ctx| {
let size = ctx.measure(
known_dimensions.width,
known_dimensions.height,
available_space.width,
available_space.height,
);
taffy::Size {
width: size.x,
height: size.y,
}
})
.unwrap_or(taffy::Size::ZERO)
},
)
.unwrap();
}
}
@ -210,7 +257,7 @@ without UI components as a child of an entity with UI components, results may be
/// Get the layout geometry for the taffy node corresponding to the ui node [`Entity`].
/// Does not compute the layout geometry, `compute_window_layouts` should be run before using this function.
pub fn get_layout(&self, entity: Entity) -> Result<&taffy::layout::Layout, LayoutError> {
pub fn get_layout(&self, entity: Entity) -> Result<&taffy::Layout, LayoutError> {
if let Some(taffy_node) = self.entity_to_taffy.get(&entity) {
self.taffy
.layout(*taffy_node)

View file

@ -4,7 +4,11 @@ use bevy_math::Vec2;
use bevy_reflect::{std_traits::ReflectDefault, Reflect};
use std::fmt::Formatter;
pub use taffy::style::AvailableSpace;
use taffy::{node::MeasureFunc, prelude::Size as TaffySize};
use crate::widget::ImageMeasure;
#[cfg(feature = "bevy_text")]
use crate::widget::TextMeasure;
impl std::fmt::Debug for ContentSize {
fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
@ -25,6 +29,44 @@ pub trait Measure: Send + Sync + 'static {
) -> Vec2;
}
/// A type to serve as Taffy's node context (which allows the content size of leaf nodes to be computed)
///
/// It has specific variants for common built-in types to avoid making them opaque and needing to box them
/// by wrapping them in a closure and a Custom variant that allows arbitrary measurement closures if required.
pub enum NodeMeasure {
Fixed(FixedMeasure),
#[cfg(feature = "bevy_text")]
Text(TextMeasure),
Image(ImageMeasure),
Custom(Box<dyn Measure>),
}
impl Measure for NodeMeasure {
fn measure(
&self,
width: Option<f32>,
height: Option<f32>,
available_width: AvailableSpace,
available_height: AvailableSpace,
) -> Vec2 {
match self {
NodeMeasure::Fixed(fixed) => {
fixed.measure(width, height, available_width, available_height)
}
#[cfg(feature = "bevy_text")]
NodeMeasure::Text(text) => {
text.measure(width, height, available_width, available_height)
}
NodeMeasure::Image(image) => {
image.measure(width, height, available_width, available_height)
}
NodeMeasure::Custom(custom) => {
custom.measure(width, height, available_width, available_height)
}
}
}
}
/// A `FixedMeasure` is a `Measure` that ignores all constraints and
/// always returns the same size.
#[derive(Default, Clone)]
@ -51,26 +93,19 @@ impl Measure for FixedMeasure {
pub struct ContentSize {
/// The `Measure` used to compute the intrinsic size
#[reflect(ignore)]
pub(crate) measure_func: Option<MeasureFunc>,
pub(crate) measure: Option<NodeMeasure>,
}
impl ContentSize {
/// Set a `Measure` for the UI node entity with this component
pub fn set(&mut self, measure: impl Measure) {
let measure_func = move |size: TaffySize<_>, available: TaffySize<_>| {
let size = measure.measure(size.width, size.height, available.width, available.height);
TaffySize {
width: size.x,
height: size.y,
}
};
self.measure_func = Some(MeasureFunc::Boxed(Box::new(measure_func)));
pub fn set(&mut self, measure: NodeMeasure) {
self.measure = Some(measure);
}
/// Creates a `ContentSize` with a `Measure` that always returns given `size` argument, regardless of the UI layout's constraints.
pub fn fixed_size(size: Vec2) -> ContentSize {
let mut content_size = Self::default();
content_size.set(FixedMeasure { size });
content_size.set(NodeMeasure::Fixed(FixedMeasure { size }));
content_size
}
}

View file

@ -770,10 +770,12 @@ impl Default for Direction {
reflect(Serialize, Deserialize)
)]
pub enum Display {
/// Use Flexbox layout model to determine the position of this [`Node`].
/// Use Flexbox layout model to determine the position of this [`Node`]'s children.
Flex,
/// Use CSS Grid layout model to determine the position of this [`Node`].
/// Use CSS Grid layout model to determine the position of this [`Node`]'s children.
Grid,
/// Use CSS Block layout model to determine the position of this [`Node`]'s children.
Block,
/// Use no layout, don't render this node and its children.
///
/// If you want to hide a node and its children,
@ -896,8 +898,10 @@ impl Default for Overflow {
pub enum OverflowAxis {
/// Show overflowing items.
Visible,
/// Hide overflowing items.
/// Hide overflowing items by clipping.
Clip,
/// Hide overflowing items by influencing layout and then clipping.
Hidden,
}
impl OverflowAxis {

View file

@ -1,4 +1,6 @@
use crate::{measurement::AvailableSpace, ContentSize, Measure, Node, UiImage, UiScale};
use crate::{
measurement::AvailableSpace, ContentSize, Measure, Node, NodeMeasure, UiImage, UiScale,
};
use bevy_asset::Assets;
use bevy_ecs::prelude::*;
use bevy_math::{UVec2, Vec2};
@ -72,6 +74,7 @@ pub fn update_image_content_size_system(
windows: Query<&Window, With<PrimaryWindow>>,
ui_scale: Res<UiScale>,
textures: Res<Assets<Image>>,
atlases: Res<Assets<TextureAtlasLayout>>,
mut query: Query<
(
@ -100,10 +103,10 @@ pub fn update_image_content_size_system(
|| content_size.is_added()
{
image_size.size = size;
content_size.set(ImageMeasure {
content_size.set(NodeMeasure::Image(ImageMeasure {
// multiply the image size by the scale factor to get the physical size
size: size.as_vec2() * combined_scale_factor,
});
}));
}
}
}

View file

@ -1,4 +1,4 @@
use crate::{ContentSize, FixedMeasure, Measure, Node, UiScale};
use crate::{ContentSize, FixedMeasure, Measure, Node, NodeMeasure, UiScale};
use bevy_asset::Assets;
use bevy_ecs::{
prelude::{Component, DetectChanges},
@ -88,9 +88,9 @@ fn create_text_measure(
match TextMeasureInfo::from_text(&text, fonts, scale_factor) {
Ok(measure) => {
if text.linebreak_behavior == BreakLineOn::NoWrap {
content_size.set(FixedMeasure { size: measure.max });
content_size.set(NodeMeasure::Fixed(FixedMeasure { size: measure.max }));
} else {
content_size.set(TextMeasure { info: measure });
content_size.set(NodeMeasure::Text(TextMeasure { info: measure }));
}
// Text measure func created successfully, so set `TextFlags` to schedule a recompute

View file

@ -54,7 +54,7 @@ impl TargetUpdate for Target<Display> {
style.display = match style.display {
Display::Flex => Display::None,
Display::None => Display::Flex,
Display::Grid => unreachable!(),
Display::Block | Display::Grid => unreachable!(),
};
format!("{}::{:?} ", Self::NAME, style.display)
}