use crate::{UiRect, Val}; use bevy_asset::Handle; use bevy_ecs::{prelude::Component, reflect::ReflectComponent}; use bevy_math::{Rect, Vec2}; use bevy_reflect::prelude::*; use bevy_render::{color::Color, texture::Image}; use bevy_transform::prelude::GlobalTransform; use serde::{Deserialize, Serialize}; use smallvec::SmallVec; use std::num::{NonZeroI16, NonZeroU16}; use thiserror::Error; /// Describes the size of a UI node #[derive(Component, Debug, Copy, Clone, Reflect)] #[reflect(Component, Default)] pub struct Node { /// The size of the node as width and height in logical pixels. /// /// Automatically calculated by [`super::layout::ui_layout_system`]. pub(crate) calculated_size: Vec2, /// The width of this node's outline. /// If this value is `Auto`, negative or `0.` then no outline will be rendered. /// /// Automatically calculated by [`super::layout::resolve_outlines_system`]. pub(crate) outline_width: f32, /// The amount of space between the outline and the edge of the node. pub(crate) outline_offset: f32, /// The unrounded size of the node as width and height in logical pixels. /// /// Automatically calculated by [`super::layout::ui_layout_system`]. pub(crate) unrounded_size: Vec2, } impl Node { /// The calculated node size as width and height in logical pixels. /// /// Automatically calculated by [`super::layout::ui_layout_system`]. pub const fn size(&self) -> Vec2 { self.calculated_size } /// The calculated node size as width and height in logical pixels before rounding. /// /// Automatically calculated by [`super::layout::ui_layout_system`]. pub const fn unrounded_size(&self) -> Vec2 { self.unrounded_size } /// Returns the size of the node in physical pixels based on the given scale factor and `UiScale`. #[inline] pub fn physical_size(&self, scale_factor: f64, ui_scale: f64) -> Vec2 { Vec2::new( (self.calculated_size.x as f64 * scale_factor * ui_scale) as f32, (self.calculated_size.y as f64 * scale_factor * ui_scale) as f32, ) } /// Returns the logical pixel coordinates of the UI node, based on its [`GlobalTransform`]. #[inline] pub fn logical_rect(&self, transform: &GlobalTransform) -> Rect { Rect::from_center_size(transform.translation().truncate(), self.size()) } /// Returns the physical pixel coordinates of the UI node, based on its [`GlobalTransform`] and the scale factor. #[inline] pub fn physical_rect( &self, transform: &GlobalTransform, scale_factor: f64, ui_scale: f64, ) -> Rect { let rect = self.logical_rect(transform); Rect { min: Vec2::new( (rect.min.x as f64 * scale_factor * ui_scale) as f32, (rect.min.y as f64 * scale_factor * ui_scale) as f32, ), max: Vec2::new( (rect.max.x as f64 * scale_factor * ui_scale) as f32, (rect.max.y as f64 * scale_factor * ui_scale) as f32, ), } } #[inline] /// Returns the thickness of the UI node's outline. /// If this value is negative or `0.` then no outline will be rendered. pub fn outline_width(&self) -> f32 { self.outline_width } } impl Node { pub const DEFAULT: Self = Self { calculated_size: Vec2::ZERO, outline_width: 0., outline_offset: 0., unrounded_size: Vec2::ZERO, }; } impl Default for Node { fn default() -> Self { Self::DEFAULT } } /// Describes the style of a UI container node /// /// Nodes can be laid out using either Flexbox or CSS Grid Layout. /// /// See below for general learning resources and for documentation on the individual style properties. /// /// ### Flexbox /// /// - [MDN: Basic Concepts of Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Flexible_Box_Layout/Basic_Concepts_of_Flexbox) /// - [A Complete Guide To Flexbox](https://css-tricks.com/snippets/css/a-guide-to-flexbox/) by CSS Tricks. This is detailed guide with illustrations and comprehensive written explanation of the different Flexbox properties and how they work. /// - [Flexbox Froggy](https://flexboxfroggy.com/). An interactive tutorial/game that teaches the essential parts of Flexbox in a fun engaging way. /// /// ### CSS Grid /// /// - [MDN: Basic Concepts of Grid Layout](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Grid_Layout/Basic_Concepts_of_Grid_Layout) /// - [A Complete Guide To CSS Grid](https://css-tricks.com/snippets/css/complete-guide-grid/) by CSS Tricks. This is detailed guide with illustrations and comprehensive written explanation of the different CSS Grid properties and how they work. /// - [CSS Grid Garden](https://cssgridgarden.com/). An interactive tutorial/game that teaches the essential parts of CSS Grid in a fun engaging way. #[derive(Component, Clone, PartialEq, Debug, Deserialize, Serialize, Reflect)] #[reflect(Component, Default, PartialEq, Deserialize, Serialize)] pub struct Style { /// Which layout algorithm to use when laying out this node's contents: /// - [`Display::Flex`]: Use the Flexbox layout algorithm /// - [`Display::Grid`]: Use the CSS Grid layout algorithm /// - [`Display::None`]: Hide this node and perform layout as if it does not exist. /// /// pub display: Display, /// Whether a node should be laid out in-flow with, or independently of its siblings: /// - [`PositionType::Relative`]: Layout this node in-flow with other nodes using the usual (flexbox/grid) layout algorithm. /// - [`PositionType::Absolute`]: Layout this node on top and independently of other nodes. /// /// pub position_type: PositionType, /// Whether overflowing content should be displayed or clipped. /// /// pub overflow: Overflow, /// Defines the text direction. For example, English is written LTR (left-to-right) while Arabic is written RTL (right-to-left). /// /// Note: the corresponding CSS property also affects box layout order, but this isn't yet implemented in Bevy. /// /// pub direction: Direction, /// The horizontal position of the left edge of the node. /// - For relatively positioned nodes, this is relative to the node's position as computed during regular layout. /// - For absolutely positioned nodes, this is relative to the *parent* node's bounding box. /// /// pub left: Val, /// The horizontal position of the right edge of the node. /// - For relatively positioned nodes, this is relative to the node's position as computed during regular layout. /// - For absolutely positioned nodes, this is relative to the *parent* node's bounding box. /// /// pub right: Val, /// The vertical position of the top edge of the node. /// - For relatively positioned nodes, this is relative to the node's position as computed during regular layout. /// - For absolutely positioned nodes, this is relative to the *parent* node's bounding box. /// /// pub top: Val, /// The vertical position of the bottom edge of the node. /// - For relatively positioned nodes, this is relative to the node's position as computed during regular layout. /// - For absolutely positioned nodes, this is relative to the *parent* node's bounding box. /// /// pub bottom: Val, /// The ideal width of the node. `width` is used when it is within the bounds defined by `min_width` and `max_width`. /// /// pub width: Val, /// The ideal height of the node. `height` is used when it is within the bounds defined by `min_height` and `max_height`. /// /// pub height: Val, /// The minimum width of the node. `min_width` is used if it is greater than `width` and/or `max_width`. /// /// pub min_width: Val, /// The minimum height of the node. `min_height` is used if it is greater than `height` and/or `max_height`. /// /// pub min_height: Val, /// The maximum width of the node. `max_width` is used if it is within the bounds defined by `min_width` and `width`. /// /// pub max_width: Val, /// The maximum height of the node. `max_height` is used if it is within the bounds defined by `min_height` and `height`. /// /// pub max_height: Val, /// The aspect ratio of the node (defined as `width / height`) /// /// pub aspect_ratio: Option, /// Used to control how each individual item is aligned by default within the space they're given. /// - For Flexbox containers, sets default cross axis alignment of the child items. /// - For CSS Grid containers, controls block (vertical) axis alignment of children of this grid container within their grid areas. /// /// This value is overridden if [`AlignSelf`] on the child node is set. /// /// pub align_items: AlignItems, /// Used to control how each individual item is aligned by default within the space they're given. /// - For Flexbox containers, this property has no effect. See `justify_content` for main axis alignment of flex items. /// - For CSS Grid containers, sets default inline (horizontal) axis alignment of child items within their grid areas. /// /// This value is overridden if [`JustifySelf`] on the child node is set. /// /// pub justify_items: JustifyItems, /// Used to control how the specified item is aligned within the space it's given. /// - For Flexbox items, controls cross axis alignment of the item. /// - For CSS Grid items, controls block (vertical) axis alignment of a grid item within its grid area. /// /// If set to `Auto`, alignment is inherited from the value of [`AlignItems`] set on the parent node. /// /// pub align_self: AlignSelf, /// Used to control how the specified item is aligned within the space it's given. /// - For Flexbox items, this property has no effect. See `justify_content` for main axis alignment of flex items. /// - For CSS Grid items, controls inline (horizontal) axis alignment of a grid item within its grid area. /// /// If set to `Auto`, alignment is inherited from the value of [`JustifyItems`] set on the parent node. /// /// pub justify_self: JustifySelf, /// Used to control how items are distributed. /// - For Flexbox containers, controls alignment of lines if `flex_wrap` is set to [`FlexWrap::Wrap`] and there are multiple lines of items. /// - For CSS Grid containers, controls alignment of grid rows. /// /// pub align_content: AlignContent, /// Used to control how items are distributed. /// - For Flexbox containers, controls alignment of items in the main axis. /// - For CSS Grid containers, controls alignment of grid columns. /// /// pub justify_content: JustifyContent, /// The amount of space around a node outside its border. /// /// If a percentage value is used, the percentage is calculated based on the width of the parent node. /// /// # Example /// ``` /// # use bevy_ui::{Style, UiRect, Val}; /// let style = Style { /// margin: UiRect { /// left: Val::Percent(10.), /// right: Val::Percent(10.), /// top: Val::Percent(15.), /// bottom: Val::Percent(15.) /// }, /// ..Default::default() /// }; /// ``` /// A node with this style and a parent with dimensions of 100px by 300px will have calculated margins of 10px on both left and right edges, and 15px on both top and bottom edges. /// /// pub margin: UiRect, /// The amount of space between the edges of a node and its contents. /// /// If a percentage value is used, the percentage is calculated based on the width of the parent node. /// /// # Example /// ``` /// # use bevy_ui::{Style, UiRect, Val}; /// let style = Style { /// padding: UiRect { /// left: Val::Percent(1.), /// right: Val::Percent(2.), /// top: Val::Percent(3.), /// bottom: Val::Percent(4.) /// }, /// ..Default::default() /// }; /// ``` /// A node with this style and a parent with dimensions of 300px by 100px will have calculated padding of 3px on the left, 6px on the right, 9px on the top and 12px on the bottom. /// /// pub padding: UiRect, /// The amount of space between the margins of a node and its padding. /// /// If a percentage value is used, the percentage is calculated based on the width of the parent node. /// /// The size of the node will be expanded if there are constraints that prevent the layout algorithm from placing the border within the existing node boundary. /// /// pub border: UiRect, /// Whether a Flexbox container should be a row or a column. This property has no effect on Grid nodes. /// /// pub flex_direction: FlexDirection, /// Whether a Flexbox container should wrap its contents onto multiple lines if they overflow. This property has no effect on Grid nodes. /// /// pub flex_wrap: FlexWrap, /// Defines how much a flexbox item should grow if there's space available. Defaults to 0 (don't grow at all). /// /// pub flex_grow: f32, /// Defines how much a flexbox item should shrink if there's not enough space available. Defaults to 1. /// /// pub flex_shrink: f32, /// The initial length of a flexbox in the main axis, before flex growing/shrinking properties are applied. /// /// `flex_basis` overrides `size` on the main axis if both are set, but it obeys the bounds defined by `min_size` and `max_size`. /// /// pub flex_basis: Val, /// The size of the gutters between items in a vertical flexbox layout or between rows in a grid layout. /// /// Note: Values of `Val::Auto` are not valid and are treated as zero. /// /// pub row_gap: Val, /// The size of the gutters between items in a horizontal flexbox layout or between column in a grid layout. /// /// Note: Values of `Val::Auto` are not valid and are treated as zero. /// /// pub column_gap: Val, /// Controls whether automatically placed grid items are placed row-wise or column-wise as well as whether the sparse or dense packing algorithm is used. /// Only affects Grid layouts. /// /// pub grid_auto_flow: GridAutoFlow, /// Defines the number of rows a grid has and the sizes of those rows. If grid items are given explicit placements then more rows may /// be implicitly generated by items that are placed out of bounds. The sizes of those rows are controlled by `grid_auto_rows` property. /// /// pub grid_template_rows: Vec, /// Defines the number of columns a grid has and the sizes of those columns. If grid items are given explicit placements then more columns may /// be implicitly generated by items that are placed out of bounds. The sizes of those columns are controlled by `grid_auto_columns` property. /// /// pub grid_template_columns: Vec, /// Defines the size of implicitly created rows. Rows are created implicitly when grid items are given explicit placements that are out of bounds /// of the rows explicitly created using `grid_template_rows`. /// /// pub grid_auto_rows: Vec, /// Defines the size of implicitly created columns. Columns are created implicitly when grid items are given explicit placements that are out of bounds /// of the columns explicitly created using `grid_template_columns`. /// /// pub grid_auto_columns: Vec, /// The row in which a grid item starts and how many rows it spans. /// /// pub grid_row: GridPlacement, /// The column in which a grid item starts and how many columns it spans. /// /// pub grid_column: GridPlacement, } impl Style { pub const DEFAULT: Self = Self { display: Display::DEFAULT, position_type: PositionType::DEFAULT, left: Val::Auto, right: Val::Auto, top: Val::Auto, bottom: Val::Auto, direction: Direction::DEFAULT, flex_direction: FlexDirection::DEFAULT, flex_wrap: FlexWrap::DEFAULT, align_items: AlignItems::DEFAULT, justify_items: JustifyItems::DEFAULT, align_self: AlignSelf::DEFAULT, justify_self: JustifySelf::DEFAULT, align_content: AlignContent::DEFAULT, justify_content: JustifyContent::DEFAULT, margin: UiRect::DEFAULT, padding: UiRect::DEFAULT, border: UiRect::DEFAULT, flex_grow: 0.0, flex_shrink: 1.0, flex_basis: Val::Auto, width: Val::Auto, height: Val::Auto, min_width: Val::Auto, min_height: Val::Auto, max_width: Val::Auto, max_height: Val::Auto, aspect_ratio: None, overflow: Overflow::DEFAULT, row_gap: Val::ZERO, column_gap: Val::ZERO, grid_auto_flow: GridAutoFlow::DEFAULT, grid_template_rows: Vec::new(), grid_template_columns: Vec::new(), grid_auto_rows: Vec::new(), grid_auto_columns: Vec::new(), grid_column: GridPlacement::DEFAULT, grid_row: GridPlacement::DEFAULT, }; } impl Default for Style { fn default() -> Self { Self::DEFAULT } } /// Used to control how each individual item is aligned by default within the space they're given. /// - For Flexbox containers, sets default cross axis alignment of the child items. /// - For CSS Grid containers, controls block (vertical) axis alignment of children of this grid container within their grid areas. /// /// #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum AlignItems { /// The items are packed in their default position as if no alignment was applied. Default, /// The items are packed towards the start of the axis. Start, /// The items are packed towards the end of the axis. End, /// The items are packed towards the start of the axis, unless the flex direction is reversed; /// then they are packed towards the end of the axis. FlexStart, /// The items are packed towards the end of the axis, unless the flex direction is reversed; /// then they are packed towards the start of the axis. FlexEnd, /// The items are packed along the center of the axis. Center, /// The items are packed such that their baselines align. Baseline, /// The items are stretched to fill the space they're given. Stretch, } impl AlignItems { pub const DEFAULT: Self = Self::Default; } impl Default for AlignItems { fn default() -> Self { Self::DEFAULT } } /// Used to control how each individual item is aligned by default within the space they're given. /// - For Flexbox containers, this property has no effect. See `justify_content` for main axis alignment of flex items. /// - For CSS Grid containers, sets default inline (horizontal) axis alignment of child items within their grid areas. /// /// #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum JustifyItems { /// The items are packed in their default position as if no alignment was applied. Default, /// The items are packed towards the start of the axis. Start, /// The items are packed towards the end of the axis. End, /// The items are packed along the center of the axis Center, /// The items are packed such that their baselines align. Baseline, /// The items are stretched to fill the space they're given. Stretch, } impl JustifyItems { pub const DEFAULT: Self = Self::Default; } impl Default for JustifyItems { fn default() -> Self { Self::DEFAULT } } /// Used to control how the specified item is aligned within the space it's given. /// - For Flexbox items, controls cross axis alignment of the item. /// - For CSS Grid items, controls block (vertical) axis alignment of a grid item within its grid area. /// /// #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum AlignSelf { /// Use the parent node's [`AlignItems`] value to determine how this item should be aligned. Auto, /// This item will be aligned with the start of the axis. Start, /// This item will be aligned with the end of the axis. End, /// This item will be aligned with the start of the axis, unless the flex direction is reversed; /// then it will be aligned with the end of the axis. FlexStart, /// This item will be aligned with the end of the axis, unless the flex direction is reversed; /// then it will be aligned with the start of the axis. FlexEnd, /// This item will be aligned along the center of the axis. Center, /// This item will be aligned at the baseline. Baseline, /// This item will be stretched to fill the container. Stretch, } impl AlignSelf { pub const DEFAULT: Self = Self::Auto; } impl Default for AlignSelf { fn default() -> Self { Self::DEFAULT } } /// Used to control how the specified item is aligned within the space it's given. /// - For Flexbox items, this property has no effect. See `justify_content` for main axis alignment of flex items. /// - For CSS Grid items, controls inline (horizontal) axis alignment of a grid item within its grid area. /// /// #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum JustifySelf { /// Use the parent node's [`JustifyItems`] value to determine how this item should be aligned. Auto, /// This item will be aligned with the start of the axis. Start, /// This item will be aligned with the end of the axis. End, /// This item will be aligned along the center of the axis. Center, /// This item will be aligned at the baseline. Baseline, /// This item will be stretched to fill the space it's given. Stretch, } impl JustifySelf { pub const DEFAULT: Self = Self::Auto; } impl Default for JustifySelf { fn default() -> Self { Self::DEFAULT } } /// Used to control how items are distributed. /// - For Flexbox containers, controls alignment of lines if `flex_wrap` is set to [`FlexWrap::Wrap`] and there are multiple lines of items. /// - For CSS Grid containers, controls alignment of grid rows. /// /// #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum AlignContent { /// The items are packed in their default position as if no alignment was applied. Default, /// The items are packed towards the start of the axis. Start, /// The items are packed towards the end of the axis. End, /// The items are packed towards the start of the axis, unless the flex direction is reversed; /// then the items are packed towards the end of the axis. FlexStart, /// The items are packed towards the end of the axis, unless the flex direction is reversed; /// then the items are packed towards the start of the axis. FlexEnd, /// The items are packed along the center of the axis. Center, /// The items are stretched to fill the container along the axis. Stretch, /// The items are distributed such that the gap between any two items is equal. SpaceBetween, /// The items are distributed such that the gap between and around any two items is equal. SpaceEvenly, /// The items are distributed such that the gap between and around any two items is equal, with half-size gaps on either end. SpaceAround, } impl AlignContent { pub const DEFAULT: Self = Self::Default; } impl Default for AlignContent { fn default() -> Self { Self::DEFAULT } } /// Used to control how items are distributed. /// - For Flexbox containers, controls alignment of items in the main axis. /// - For CSS Grid containers, controls alignment of grid columns. /// /// #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum JustifyContent { /// The items are packed in their default position as if no alignment was applied. Default, /// The items are packed towards the start of the axis. Start, /// The items are packed towards the end of the axis. End, /// The items are packed towards the start of the axis, unless the flex direction is reversed; /// then the items are packed towards the end of the axis. FlexStart, /// The items are packed towards the end of the axis, unless the flex direction is reversed; /// then the items are packed towards the start of the axis. FlexEnd, /// The items are packed along the center of the axis. Center, /// The items are stretched to fill the container along the axis. Stretch, /// The items are distributed such that the gap between any two items is equal. SpaceBetween, /// The items are distributed such that the gap between and around any two items is equal. SpaceEvenly, /// The items are distributed such that the gap between and around any two items is equal, with half-size gaps on either end. SpaceAround, } impl JustifyContent { pub const DEFAULT: Self = Self::Default; } impl Default for JustifyContent { fn default() -> Self { Self::DEFAULT } } /// Defines the text direction. /// /// For example, English is written LTR (left-to-right) while Arabic is written RTL (right-to-left). #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum Direction { /// Inherit from parent node. Inherit, /// Text is written left to right. LeftToRight, /// Text is written right to left. RightToLeft, } impl Direction { pub const DEFAULT: Self = Self::Inherit; } impl Default for Direction { fn default() -> Self { Self::DEFAULT } } /// Defines the layout model used by this node. /// /// Part of the [`Style`] component. #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum Display { /// Use Flexbox layout model to determine the position of this [`Node`]. Flex, /// Use CSS Grid layout model to determine the position of this [`Node`]. Grid, /// Use no layout, don't render this node and its children. /// /// If you want to hide a node and its children, /// but keep its layout in place, set its [`Visibility`](bevy_render::view::Visibility) component instead. None, } impl Display { pub const DEFAULT: Self = Self::Flex; } impl Default for Display { fn default() -> Self { Self::DEFAULT } } /// Defines how flexbox items are ordered within a flexbox #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum FlexDirection { /// Same way as text direction along the main axis. Row, /// Flex from top to bottom. Column, /// Opposite way as text direction along the main axis. RowReverse, /// Flex from bottom to top. ColumnReverse, } impl FlexDirection { pub const DEFAULT: Self = Self::Row; } impl Default for FlexDirection { fn default() -> Self { Self::DEFAULT } } /// Whether to show or hide overflowing items #[derive(Copy, Clone, PartialEq, Eq, Debug, Reflect, Serialize, Deserialize)] #[reflect(PartialEq, Serialize, Deserialize)] pub struct Overflow { /// Whether to show or clip overflowing items on the x axis pub x: OverflowAxis, /// Whether to show or clip overflowing items on the y axis pub y: OverflowAxis, } impl Overflow { pub const DEFAULT: Self = Self { x: OverflowAxis::DEFAULT, y: OverflowAxis::DEFAULT, }; /// Show overflowing items on both axes pub const fn visible() -> Self { Self { x: OverflowAxis::Visible, y: OverflowAxis::Visible, } } /// Clip overflowing items on both axes pub const fn clip() -> Self { Self { x: OverflowAxis::Clip, y: OverflowAxis::Clip, } } /// Clip overflowing items on the x axis pub const fn clip_x() -> Self { Self { x: OverflowAxis::Clip, y: OverflowAxis::Visible, } } /// Clip overflowing items on the y axis pub const fn clip_y() -> Self { Self { x: OverflowAxis::Visible, y: OverflowAxis::Clip, } } /// Overflow is visible on both axes pub const fn is_visible(&self) -> bool { self.x.is_visible() && self.y.is_visible() } } impl Default for Overflow { fn default() -> Self { Self::DEFAULT } } /// Whether to show or hide overflowing items #[derive(Copy, Clone, PartialEq, Eq, Debug, Reflect, Serialize, Deserialize)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum OverflowAxis { /// Show overflowing items. Visible, /// Hide overflowing items. Clip, } impl OverflowAxis { pub const DEFAULT: Self = Self::Visible; /// Overflow is visible on this axis pub const fn is_visible(&self) -> bool { matches!(self, Self::Visible) } } impl Default for OverflowAxis { fn default() -> Self { Self::DEFAULT } } /// The strategy used to position this node #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum PositionType { /// Relative to all other nodes with the [`PositionType::Relative`] value. Relative, /// Independent of all other nodes, but relative to its parent node. Absolute, } impl PositionType { pub const DEFAULT: Self = Self::Relative; } impl Default for PositionType { fn default() -> Self { Self::DEFAULT } } /// Defines if flexbox items appear on a single line or on multiple lines #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum FlexWrap { /// Single line, will overflow if needed. NoWrap, /// Multiple lines, if needed. Wrap, /// Same as [`FlexWrap::Wrap`] but new lines will appear before the previous one. WrapReverse, } impl FlexWrap { pub const DEFAULT: Self = Self::NoWrap; } impl Default for FlexWrap { fn default() -> Self { Self::DEFAULT } } /// Controls whether grid items are placed row-wise or column-wise as well as whether the sparse or dense packing algorithm is used. /// /// The "dense" packing algorithm attempts to fill in holes earlier in the grid, if smaller items come up later. /// This may cause items to appear out-of-order when doing so would fill in holes left by larger items. /// /// Defaults to [`GridAutoFlow::Row`]. /// /// #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub enum GridAutoFlow { /// Items are placed by filling each row in turn, adding new rows as necessary. Row, /// Items are placed by filling each column in turn, adding new columns as necessary. Column, /// Combines `Row` with the dense packing algorithm. RowDense, /// Combines `Column` with the dense packing algorithm. ColumnDense, } impl GridAutoFlow { pub const DEFAULT: Self = Self::Row; } impl Default for GridAutoFlow { fn default() -> Self { Self::DEFAULT } } #[derive(Copy, Clone, PartialEq, Debug, Serialize, Deserialize, Reflect)] #[reflect_value(PartialEq, Serialize, Deserialize)] pub enum MinTrackSizingFunction { /// Track minimum size should be a fixed pixel value Px(f32), /// Track minimum size should be a percentage value Percent(f32), /// Track minimum size should be content sized under a min-content constraint MinContent, /// Track minimum size should be content sized under a max-content constraint MaxContent, /// Track minimum size should be automatically sized Auto, } #[derive(Copy, Clone, PartialEq, Debug, Serialize, Deserialize, Reflect)] #[reflect_value(PartialEq, Serialize, Deserialize)] pub enum MaxTrackSizingFunction { /// Track maximum size should be a fixed pixel value Px(f32), /// Track maximum size should be a percentage value Percent(f32), /// Track maximum size should be content sized under a min-content constraint MinContent, /// Track maximum size should be content sized under a max-content constraint MaxContent, /// Track maximum size should be sized according to the fit-content formula with a fixed pixel limit FitContentPx(f32), /// Track maximum size should be sized according to the fit-content formula with a percentage limit FitContentPercent(f32), /// Track maximum size should be automatically sized Auto, /// The dimension as a fraction of the total available grid space (`fr` units in CSS) /// Specified value is the numerator of the fraction. Denominator is the sum of all fractions specified in that grid dimension. /// /// Spec: Fraction(f32), } /// A [`GridTrack`] is a Row or Column of a CSS Grid. This struct specifies what size the track should be. /// See below for the different "track sizing functions" you can specify. #[derive(Copy, Clone, PartialEq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub struct GridTrack { pub(crate) min_sizing_function: MinTrackSizingFunction, pub(crate) max_sizing_function: MaxTrackSizingFunction, } impl GridTrack { pub const DEFAULT: Self = Self { min_sizing_function: MinTrackSizingFunction::Auto, max_sizing_function: MaxTrackSizingFunction::Auto, }; /// Create a grid track with a fixed pixel size pub fn px>(value: f32) -> T { Self { min_sizing_function: MinTrackSizingFunction::Px(value), max_sizing_function: MaxTrackSizingFunction::Px(value), } .into() } /// Create a grid track with a percentage size pub fn percent>(value: f32) -> T { Self { min_sizing_function: MinTrackSizingFunction::Percent(value), max_sizing_function: MaxTrackSizingFunction::Percent(value), } .into() } /// Create a grid track with an `fr` size. /// Note that this will give the track a content-based minimum size. /// Usually you are best off using `GridTrack::flex` instead which uses a zero minimum size. pub fn fr>(value: f32) -> T { Self { min_sizing_function: MinTrackSizingFunction::Auto, max_sizing_function: MaxTrackSizingFunction::Fraction(value), } .into() } /// Create a grid track with a `minmax(0, Nfr)` size. pub fn flex>(value: f32) -> T { Self { min_sizing_function: MinTrackSizingFunction::Px(0.0), max_sizing_function: MaxTrackSizingFunction::Fraction(value), } .into() } /// Create a grid track which is automatically sized to fit its contents. pub fn auto>() -> T { Self { min_sizing_function: MinTrackSizingFunction::Auto, max_sizing_function: MaxTrackSizingFunction::Auto, } .into() } /// Create a grid track which is automatically sized to fit its contents when sized at their "min-content" sizes pub fn min_content>() -> T { Self { min_sizing_function: MinTrackSizingFunction::MinContent, max_sizing_function: MaxTrackSizingFunction::MinContent, } .into() } /// Create a grid track which is automatically sized to fit its contents when sized at their "max-content" sizes pub fn max_content>() -> T { Self { min_sizing_function: MinTrackSizingFunction::MaxContent, max_sizing_function: MaxTrackSizingFunction::MaxContent, } .into() } /// Create a fit-content() grid track with fixed pixel limit /// /// pub fn fit_content_px>(limit: f32) -> T { Self { min_sizing_function: MinTrackSizingFunction::Auto, max_sizing_function: MaxTrackSizingFunction::FitContentPx(limit), } .into() } /// Create a fit-content() grid track with percentage limit /// /// pub fn fit_content_percent>(limit: f32) -> T { Self { min_sizing_function: MinTrackSizingFunction::Auto, max_sizing_function: MaxTrackSizingFunction::FitContentPercent(limit), } .into() } /// Create a minmax() grid track /// /// pub fn minmax>(min: MinTrackSizingFunction, max: MaxTrackSizingFunction) -> T { Self { min_sizing_function: min, max_sizing_function: max, } .into() } } impl Default for GridTrack { fn default() -> Self { Self::DEFAULT } } #[derive(Copy, Clone, PartialEq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] /// How many times to repeat a repeated grid track /// /// pub enum GridTrackRepetition { /// Repeat the track fixed number of times Count(u16), /// Repeat the track to fill available space /// /// AutoFill, /// Repeat the track to fill available space but collapse any tracks that do not end up with /// an item placed in them. /// /// AutoFit, } impl From for GridTrackRepetition { fn from(count: u16) -> Self { Self::Count(count) } } impl From for GridTrackRepetition { fn from(count: i32) -> Self { Self::Count(count as u16) } } impl From for GridTrackRepetition { fn from(count: usize) -> Self { Self::Count(count as u16) } } /// Represents a *possibly* repeated [`GridTrack`]. /// /// The repetition parameter can either be: /// - The integer `1`, in which case the track is non-repeated. /// - a `u16` count to repeat the track N times. /// - A `GridTrackRepetition::AutoFit` or `GridTrackRepetition::AutoFill`. /// /// Note: that in the common case you want a non-repeating track (repetition count 1), you may use the constructor methods on [`GridTrack`] /// to create a `RepeatedGridTrack`. i.e. `GridTrack::px(10.0)` is equivalent to `RepeatedGridTrack::px(1, 10.0)`. /// /// You may only use one auto-repetition per track list. And if your track list contains an auto repetition /// then all tracks (in and outside of the repetition) must be fixed size (px or percent). Integer repetitions are just shorthand for writing out /// N tracks longhand and are not subject to the same limitations. #[derive(Clone, PartialEq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] pub struct RepeatedGridTrack { pub(crate) repetition: GridTrackRepetition, pub(crate) tracks: SmallVec<[GridTrack; 1]>, } impl RepeatedGridTrack { /// Create a repeating set of grid tracks with a fixed pixel size pub fn px>(repetition: impl Into, value: f32) -> T { Self { repetition: repetition.into(), tracks: SmallVec::from_buf([GridTrack::px(value)]), } .into() } /// Create a repeating set of grid tracks with a percentage size pub fn percent>(repetition: impl Into, value: f32) -> T { Self { repetition: repetition.into(), tracks: SmallVec::from_buf([GridTrack::percent(value)]), } .into() } /// Create a repeating set of grid tracks with automatic size pub fn auto>(repetition: u16) -> T { Self { repetition: GridTrackRepetition::Count(repetition), tracks: SmallVec::from_buf([GridTrack::auto()]), } .into() } /// Create a repeating set of grid tracks with an `fr` size. /// Note that this will give the track a content-based minimum size. /// Usually you are best off using `GridTrack::flex` instead which uses a zero minimum size. pub fn fr>(repetition: u16, value: f32) -> T { Self { repetition: GridTrackRepetition::Count(repetition), tracks: SmallVec::from_buf([GridTrack::fr(value)]), } .into() } /// Create a repeating set of grid tracks with a `minmax(0, Nfr)` size. pub fn flex>(repetition: u16, value: f32) -> T { Self { repetition: GridTrackRepetition::Count(repetition), tracks: SmallVec::from_buf([GridTrack::flex(value)]), } .into() } /// Create a repeating set of grid tracks with min-content size pub fn min_content>(repetition: u16) -> T { Self { repetition: GridTrackRepetition::Count(repetition), tracks: SmallVec::from_buf([GridTrack::min_content()]), } .into() } /// Create a repeating set of grid tracks with max-content size pub fn max_content>(repetition: u16) -> T { Self { repetition: GridTrackRepetition::Count(repetition), tracks: SmallVec::from_buf([GridTrack::max_content()]), } .into() } /// Create a repeating set of fit-content() grid tracks with fixed pixel limit pub fn fit_content_px>(repetition: u16, limit: f32) -> T { Self { repetition: GridTrackRepetition::Count(repetition), tracks: SmallVec::from_buf([GridTrack::fit_content_px(limit)]), } .into() } /// Create a repeating set of fit-content() grid tracks with percentage limit pub fn fit_content_percent>(repetition: u16, limit: f32) -> T { Self { repetition: GridTrackRepetition::Count(repetition), tracks: SmallVec::from_buf([GridTrack::fit_content_percent(limit)]), } .into() } /// Create a repeating set of minmax() grid track pub fn minmax>( repetition: impl Into, min: MinTrackSizingFunction, max: MaxTrackSizingFunction, ) -> T { Self { repetition: repetition.into(), tracks: SmallVec::from_buf([GridTrack::minmax(min, max)]), } .into() } /// Create a repetition of a set of tracks pub fn repeat_many>( repetition: impl Into, tracks: impl Into>, ) -> T { Self { repetition: repetition.into(), tracks: SmallVec::from_vec(tracks.into()), } .into() } } impl From for RepeatedGridTrack { fn from(track: GridTrack) -> Self { Self { repetition: GridTrackRepetition::Count(1), tracks: SmallVec::from_buf([track]), } } } impl From for Vec { fn from(track: GridTrack) -> Self { vec![GridTrack { min_sizing_function: track.min_sizing_function, max_sizing_function: track.max_sizing_function, }] } } impl From for Vec { fn from(track: GridTrack) -> Self { vec![RepeatedGridTrack { repetition: GridTrackRepetition::Count(1), tracks: SmallVec::from_buf([track]), }] } } impl From for Vec { fn from(track: RepeatedGridTrack) -> Self { vec![track] } } #[derive(Copy, Clone, PartialEq, Eq, Debug, Serialize, Deserialize, Reflect)] #[reflect(PartialEq, Serialize, Deserialize)] /// Represents the position of a grid item in a single axis. /// /// There are 3 fields which may be set: /// - `start`: which grid line the item should start at /// - `end`: which grid line the item should end at /// - `span`: how many tracks the item should span /// /// The default `span` is 1. If neither `start` or `end` is set then the item will be placed automatically. /// /// Generally, at most two fields should be set. If all three fields are specified then `span` will be ignored. If `end` specifies an earlier /// grid line than `start` then `end` will be ignored and the item will have a span of 1. /// /// pub struct GridPlacement { /// The grid line at which the item should start. /// Lines are 1-indexed. /// Negative indexes count backwards from the end of the grid. /// Zero is not a valid index. pub(crate) start: Option, /// How many grid tracks the item should span. /// Defaults to 1. pub(crate) span: Option, /// The grid line at which the item should end. /// Lines are 1-indexed. /// Negative indexes count backwards from the end of the grid. /// Zero is not a valid index. pub(crate) end: Option, } impl GridPlacement { pub const DEFAULT: Self = Self { start: None, span: Some(unsafe { NonZeroU16::new_unchecked(1) }), end: None, }; /// Place the grid item automatically (letting the `span` default to `1`). pub fn auto() -> Self { Self::DEFAULT } /// Place the grid item automatically, specifying how many tracks it should `span`. /// /// # Panics /// /// Panics if `span` is `0`. pub fn span(span: u16) -> Self { Self { start: None, end: None, span: try_into_grid_span(span).expect("Invalid span value of 0."), } } /// Place the grid item specifying the `start` grid line (letting the `span` default to `1`). /// /// # Panics /// /// Panics if `start` is `0`. pub fn start(start: i16) -> Self { Self { start: try_into_grid_index(start).expect("Invalid start value of 0."), ..Self::DEFAULT } } /// Place the grid item specifying the `end` grid line (letting the `span` default to `1`). /// /// # Panics /// /// Panics if `end` is `0`. pub fn end(end: i16) -> Self { Self { end: try_into_grid_index(end).expect("Invalid end value of 0."), ..Self::DEFAULT } } /// Place the grid item specifying the `start` grid line and how many tracks it should `span`. /// /// # Panics /// /// Panics if `start` or `span` is `0`. pub fn start_span(start: i16, span: u16) -> Self { Self { start: try_into_grid_index(start).expect("Invalid start value of 0."), end: None, span: try_into_grid_span(span).expect("Invalid span value of 0."), } } /// Place the grid item specifying `start` and `end` grid lines (`span` will be inferred) /// /// # Panics /// /// Panics if `start` or `end` is `0`. pub fn start_end(start: i16, end: i16) -> Self { Self { start: try_into_grid_index(start).expect("Invalid start value of 0."), end: try_into_grid_index(end).expect("Invalid end value of 0."), span: None, } } /// Place the grid item specifying the `end` grid line and how many tracks it should `span`. /// /// # Panics /// /// Panics if `end` or `span` is `0`. pub fn end_span(end: i16, span: u16) -> Self { Self { start: None, end: try_into_grid_index(end).expect("Invalid end value of 0."), span: try_into_grid_span(span).expect("Invalid span value of 0."), } } /// Mutate the item, setting the `start` grid line /// /// # Panics /// /// Panics if `start` is `0`. pub fn set_start(mut self, start: i16) -> Self { self.start = try_into_grid_index(start).expect("Invalid start value of 0."); self } /// Mutate the item, setting the `end` grid line /// /// # Panics /// /// Panics if `end` is `0`. pub fn set_end(mut self, end: i16) -> Self { self.end = try_into_grid_index(end).expect("Invalid end value of 0."); self } /// Mutate the item, setting the number of tracks the item should `span` /// /// # Panics /// /// Panics if `span` is `0`. pub fn set_span(mut self, span: u16) -> Self { self.span = try_into_grid_span(span).expect("Invalid span value of 0."); self } /// Returns the grid line at which the item should start, or `None` if not set. pub fn get_start(self) -> Option { self.start.map(NonZeroI16::get) } /// Returns the grid line at which the item should end, or `None` if not set. pub fn get_end(self) -> Option { self.end.map(NonZeroI16::get) } /// Returns span for this grid item, or `None` if not set. pub fn get_span(self) -> Option { self.span.map(NonZeroU16::get) } } impl Default for GridPlacement { fn default() -> Self { Self::DEFAULT } } /// Convert an `i16` to `NonZeroI16`, fails on `0` and returns the `InvalidZeroIndex` error. fn try_into_grid_index(index: i16) -> Result, GridPlacementError> { Ok(Some( NonZeroI16::new(index).ok_or(GridPlacementError::InvalidZeroIndex)?, )) } /// Convert a `u16` to `NonZeroU16`, fails on `0` and returns the `InvalidZeroSpan` error. fn try_into_grid_span(span: u16) -> Result, GridPlacementError> { Ok(Some( NonZeroU16::new(span).ok_or(GridPlacementError::InvalidZeroSpan)?, )) } /// Errors that occur when setting constraints for a `GridPlacement` #[derive(Debug, Eq, PartialEq, Clone, Copy, Error)] pub enum GridPlacementError { #[error("Zero is not a valid grid position")] InvalidZeroIndex, #[error("Spans cannot be zero length")] InvalidZeroSpan, } /// The background color of the node /// /// This serves as the "fill" color. /// When combined with [`UiImage`], tints the provided texture. #[derive(Component, Copy, Clone, Debug, Deserialize, Serialize, Reflect)] #[reflect(Component, Default, Deserialize, Serialize)] pub struct BackgroundColor(pub Color); impl BackgroundColor { pub const DEFAULT: Self = Self(Color::WHITE); } impl Default for BackgroundColor { fn default() -> Self { Self::DEFAULT } } impl From for BackgroundColor { fn from(color: Color) -> Self { Self(color) } } /// The atlas sprite to be used in a UI Texture Atlas Node #[derive(Component, Clone, Debug, Reflect, Default)] #[reflect(Component, Default)] pub struct UiTextureAtlasImage { /// Texture index in the TextureAtlas pub index: usize, /// Whether to flip the sprite in the X axis pub flip_x: bool, /// Whether to flip the sprite in the Y axis pub flip_y: bool, } /// The border color of the UI node. #[derive(Component, Copy, Clone, Debug, Deserialize, Serialize, Reflect)] #[reflect(Component, Default, Deserialize, Serialize)] pub struct BorderColor(pub Color); impl From for BorderColor { fn from(color: Color) -> Self { Self(color) } } impl BorderColor { pub const DEFAULT: Self = BorderColor(Color::WHITE); } impl Default for BorderColor { fn default() -> Self { Self::DEFAULT } } #[derive(Component, Copy, Clone, Default, Debug, Deserialize, Serialize, Reflect)] #[reflect(Component, Default, Deserialize, Serialize)] /// The [`Outline`] component adds an outline outside the edge of a UI node. /// Outlines do not take up space in the layout. /// /// To add an [`Outline`] to a ui node you can spawn a `(NodeBundle, Outline)` tuple bundle: /// ``` /// # use bevy_ecs::prelude::*; /// # use bevy_ui::prelude::*; /// # use bevy_render::prelude::Color; /// fn setup_ui(mut commands: Commands) { /// commands.spawn(( /// NodeBundle { /// style: Style { /// width: Val::Px(100.), /// height: Val::Px(100.), /// ..Default::default() /// }, /// background_color: Color::BLUE.into(), /// ..Default::default() /// }, /// Outline::new(Val::Px(10.), Val::ZERO, Color::RED) /// )); /// } /// ``` /// /// [`Outline`] components can also be added later to existing UI nodes: /// ``` /// # use bevy_ecs::prelude::*; /// # use bevy_ui::prelude::*; /// # use bevy_render::prelude::Color; /// fn outline_hovered_button_system( /// mut commands: Commands, /// mut node_query: Query<(Entity, &Interaction, Option<&mut Outline>), Changed>, /// ) { /// for (entity, interaction, mut maybe_outline) in node_query.iter_mut() { /// let outline_color = /// if matches!(*interaction, Interaction::Hovered) { /// Color::WHITE /// } else { /// Color::NONE /// }; /// if let Some(mut outline) = maybe_outline { /// outline.color = outline_color; /// } else { /// commands.entity(entity).insert(Outline::new(Val::Px(10.), Val::ZERO, outline_color)); /// } /// } /// } /// ``` /// Inserting and removing an [`Outline`] component repeatedly will result in table moves, so it is generally preferable to /// set `Outline::color` to `Color::NONE` to hide an outline. pub struct Outline { /// The width of the outline. /// /// Percentage `Val` values are resolved based on the width of the outlined [`Node`]. pub width: Val, /// The amount of space between a node's outline the edge of the node. /// /// Percentage `Val` values are resolved based on the width of the outlined [`Node`]. pub offset: Val, /// The color of the outline. /// /// If you are frequently toggling outlines for a UI node on and off it is recommended to set `Color::None` to hide the outline. /// This avoids the table moves that would occur from the repeated insertion and removal of the `Outline` component. pub color: Color, } impl Outline { /// Create a new outline pub const fn new(width: Val, offset: Val, color: Color) -> Self { Self { width, offset, color, } } } /// The 2D texture displayed for this UI node #[derive(Component, Clone, Debug, Reflect, Default)] #[reflect(Component, Default)] pub struct UiImage { /// Handle to the texture pub texture: Handle, /// Whether the image should be flipped along its x-axis pub flip_x: bool, /// Whether the image should be flipped along its y-axis pub flip_y: bool, } impl UiImage { pub fn new(texture: Handle) -> Self { Self { texture, ..Default::default() } } /// Flip the image along its x-axis #[must_use] pub const fn with_flip_x(mut self) -> Self { self.flip_x = true; self } /// Flip the image along its y-axis #[must_use] pub const fn with_flip_y(mut self) -> Self { self.flip_y = true; self } } impl From> for UiImage { fn from(texture: Handle) -> Self { Self::new(texture) } } /// The calculated clip of the node #[derive(Component, Default, Copy, Clone, Debug, Reflect)] #[reflect(Component)] pub struct CalculatedClip { /// The rect of the clip pub clip: Rect, } /// Indicates that this [`Node`] entity's front-to-back ordering is not controlled solely /// by its location in the UI hierarchy. A node with a higher z-index will appear on top /// of other nodes with a lower z-index. /// /// UI nodes that have the same z-index will appear according to the order in which they /// appear in the UI hierarchy. In such a case, the last node to be added to its parent /// will appear in front of its siblings. /// /// Internally, nodes with a global z-index share the stacking context of root UI nodes /// (nodes that have no parent). Because of this, there is no difference between using /// `ZIndex::Local(n)` and `ZIndex::Global(n)` for root nodes. /// /// Nodes without this component will be treated as if they had a value of `ZIndex::Local(0)`. #[derive(Component, Copy, Clone, Debug, Reflect)] #[reflect(Component)] pub enum ZIndex { /// Indicates the order in which this node should be rendered relative to its siblings. Local(i32), /// Indicates the order in which this node should be rendered relative to root nodes and /// all other nodes that have a global z-index. Global(i32), } impl Default for ZIndex { fn default() -> Self { Self::Local(0) } } #[cfg(test)] mod tests { use crate::GridPlacement; #[test] fn invalid_grid_placement_values() { assert!(std::panic::catch_unwind(|| GridPlacement::span(0)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::start(0)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::end(0)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::start_end(0, 1)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::start_end(-1, 0)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::start_span(1, 0)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::start_span(0, 1)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::end_span(0, 1)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::end_span(1, 0)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::default().set_start(0)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::default().set_end(0)).is_err()); assert!(std::panic::catch_unwind(|| GridPlacement::default().set_span(0)).is_err()); } #[test] fn grid_placement_accessors() { assert_eq!(GridPlacement::start(5).get_start(), Some(5)); assert_eq!(GridPlacement::end(-4).get_end(), Some(-4)); assert_eq!(GridPlacement::span(2).get_span(), Some(2)); assert_eq!(GridPlacement::start_end(11, 21).get_span(), None); assert_eq!(GridPlacement::start_span(3, 5).get_end(), None); assert_eq!(GridPlacement::end_span(-4, 12).get_start(), None); } }