Draft new layout API

10 files changed, 98 insertions, 161 deletions

diff --git a/native/src/widget/button.rs b/native/src/widget/button.rs
index 31dd6fcc..882d4a6c 100644
--- a/native/src/widget/button.rs
+++ b/native/src/widget/button.rs
@@ -7,7 +7,7 @@
 //! [`Class`]: enum.Class.html
 
 use crate::input::{mouse, ButtonState};
-use crate::{Element, Event, Hasher, Layout, Node, Point, Widget};
+use crate::{layout, Element, Event, Hasher, Layout, Point, Widget};
 use std::hash::Hash;
 
 pub use iced_core::button::State;
@@ -21,14 +21,14 @@ where
     Renderer: self::Renderer,
     Message: Clone + std::fmt::Debug,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        renderer.node(&self)
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        renderer.layout(&self, limits)
     }
 
     fn on_event(
         &mut self,
         event: Event,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
         messages: &mut Vec<Message>,
         _renderer: &Renderer,
@@ -66,7 +66,7 @@ where
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Renderer::Output {
         renderer.draw(&self, layout, cursor_position)
@@ -91,7 +91,11 @@ pub trait Renderer: crate::Renderer + Sized {
     ///
     /// [`Node`]: ../../struct.Node.html
     /// [`Button`]: struct.Button.html
-    fn node<Message>(&self, button: &Button<'_, Message, Self>) -> Node;
+    fn layout<Message>(
+        &self,
+        button: &Button<'_, Message, Self>,
+        limits: &layout::Limits,
+    ) -> Layout;
 
     /// Draws a [`Button`].
     ///
@@ -99,7 +103,7 @@ pub trait Renderer: crate::Renderer + Sized {
     fn draw<Message>(
         &mut self,
         button: &Button<'_, Message, Self>,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Self::Output;
 }
diff --git a/native/src/widget/checkbox.rs b/native/src/widget/checkbox.rs
index b8053238..12a6a728 100644
--- a/native/src/widget/checkbox.rs
+++ b/native/src/widget/checkbox.rs
@@ -2,7 +2,7 @@
 use std::hash::Hash;
 
 use crate::input::{mouse, ButtonState};
-use crate::{Element, Event, Hasher, Layout, Node, Point, Widget};
+use crate::{layout, Element, Event, Hasher, Layout, Point, Widget};
 
 pub use iced_core::Checkbox;
 
@@ -10,14 +10,14 @@ impl<Message, Renderer> Widget<Message, Renderer> for Checkbox<Message>
 where
     Renderer: self::Renderer,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        renderer.node(&self)
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        renderer.layout(&self, limits)
     }
 
     fn on_event(
         &mut self,
         event: Event,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
         messages: &mut Vec<Message>,
         _renderer: &Renderer,
@@ -40,7 +40,7 @@ where
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Renderer::Output {
         renderer.draw(&self, layout, cursor_position)
@@ -63,7 +63,11 @@ pub trait Renderer: crate::Renderer {
     ///
     /// [`Node`]: ../../struct.Node.html
     /// [`Checkbox`]: struct.Checkbox.html
-    fn node<Message>(&self, checkbox: &Checkbox<Message>) -> Node;
+    fn layout<Message>(
+        &self,
+        checkbox: &Checkbox<Message>,
+        limits: &layout::Limits,
+    ) -> Layout;
 
     /// Draws a [`Checkbox`].
     ///
@@ -77,7 +81,7 @@ pub trait Renderer: crate::Renderer {
     fn draw<Message>(
         &mut self,
         checkbox: &Checkbox<Message>,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Self::Output;
 }
diff --git a/native/src/widget/column.rs b/native/src/widget/column.rs
index 086d05ef..d0446ec9 100644
--- a/native/src/widget/column.rs
+++ b/native/src/widget/column.rs
@@ -1,6 +1,6 @@
 use std::hash::Hash;
 
-use crate::{Element, Event, Hasher, Layout, Node, Point, Style, Widget};
+use crate::{layout, Element, Event, Hasher, Layout, Point, Rectangle, Widget};
 
 /// A container that distributes its contents vertically.
 pub type Column<'a, Message, Renderer> =
@@ -11,48 +11,20 @@ impl<'a, Message, Renderer> Widget<Message, Renderer>
 where
     Renderer: self::Renderer,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        let mut children: Vec<Node> = self
-            .children
-            .iter()
-            .map(|child| {
-                let mut node = child.widget.node(renderer);
-
-                let mut style = node.0.style();
-                style.margin.bottom =
-                    stretch::style::Dimension::Points(f32::from(self.spacing));
-
-                node.0.set_style(style);
-                node
-            })
-            .collect();
-
-        if let Some(node) = children.last_mut() {
-            let mut style = node.0.style();
-            style.margin.bottom = stretch::style::Dimension::Undefined;
-
-            node.0.set_style(style);
-        }
-
-        let mut style = Style::default()
-            .width(self.width)
-            .height(self.height)
-            .max_width(self.max_width)
-            .max_height(self.max_height)
-            .padding(self.padding)
-            .align_self(self.align_self)
-            .align_items(self.align_items)
-            .justify_content(self.justify_content);
-
-        style.0.flex_direction = stretch::style::FlexDirection::Column;
-
-        Node::with_children(style, children)
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        // TODO
+        Layout::new(Rectangle {
+            x: 0.0,
+            y: 0.0,
+            width: 0.0,
+            height: 0.0,
+        })
     }
 
     fn on_event(
         &mut self,
         event: Event,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
         messages: &mut Vec<Message>,
         renderer: &Renderer,
@@ -73,7 +45,7 @@ where
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Renderer::Output {
         renderer.draw(&self, layout, cursor_position)
@@ -100,7 +72,7 @@ pub trait Renderer: crate::Renderer + Sized {
     fn draw<Message>(
         &mut self,
         row: &Column<'_, Message, Self>,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Self::Output;
 }
diff --git a/native/src/widget/image.rs b/native/src/widget/image.rs
index 6255a7b5..b503f95c 100644
--- a/native/src/widget/image.rs
+++ b/native/src/widget/image.rs
@@ -1,6 +1,6 @@
 //! Display images in your user interface.
 
-use crate::{Element, Hasher, Layout, Node, Point, Widget};
+use crate::{layout, Element, Hasher, Layout, Point, Widget};
 
 use std::hash::Hash;
 
@@ -10,14 +10,14 @@ impl<Message, Renderer> Widget<Message, Renderer> for Image
 where
     Renderer: self::Renderer,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        renderer.node(&self)
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        renderer.layout(&self, limits)
     }
 
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         _cursor_position: Point,
     ) -> Renderer::Output {
         renderer.draw(&self, layout)
@@ -44,12 +44,12 @@ pub trait Renderer: crate::Renderer {
     ///
     /// [`Node`]: ../../struct.Node.html
     /// [`Image`]: struct.Image.html
-    fn node(&self, image: &Image) -> Node;
+    fn layout(&self, image: &Image, limits: &layout::Limits) -> Layout;
 
     /// Draws an [`Image`].
     ///
     /// [`Image`]: struct.Image.html
-    fn draw(&mut self, image: &Image, layout: Layout<'_>) -> Self::Output;
+    fn draw(&mut self, image: &Image, layout: &Layout) -> Self::Output;
 }
 
 impl<'a, Message, Renderer> From<Image> for Element<'a, Message, Renderer>
diff --git a/native/src/widget/radio.rs b/native/src/widget/radio.rs
index 626e6ffc..86d507da 100644
--- a/native/src/widget/radio.rs
+++ b/native/src/widget/radio.rs
@@ -1,6 +1,6 @@
 //! Create choices using radio buttons.
 use crate::input::{mouse, ButtonState};
-use crate::{Element, Event, Hasher, Layout, Node, Point, Widget};
+use crate::{layout, Element, Event, Hasher, Layout, Point, Widget};
 
 use std::hash::Hash;
 
@@ -11,14 +11,14 @@ where
     Renderer: self::Renderer,
     Message: Clone + std::fmt::Debug,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        renderer.node(&self)
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        renderer.layout(&self, limits)
     }
 
     fn on_event(
         &mut self,
         event: Event,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
         messages: &mut Vec<Message>,
         _renderer: &Renderer,
@@ -39,7 +39,7 @@ where
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Renderer::Output {
         renderer.draw(&self, layout, cursor_position)
@@ -62,7 +62,11 @@ pub trait Renderer: crate::Renderer {
     ///
     /// [`Node`]: ../../struct.Node.html
     /// [`Radio`]: struct.Radio.html
-    fn node<Message>(&self, radio: &Radio<Message>) -> Node;
+    fn layout<Message>(
+        &self,
+        radio: &Radio<Message>,
+        limits: &layout::Limits,
+    ) -> Layout;
 
     /// Draws a [`Radio`] button.
     ///
@@ -76,7 +80,7 @@ pub trait Renderer: crate::Renderer {
     fn draw<Message>(
         &mut self,
         radio: &Radio<Message>,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Self::Output;
 }
diff --git a/native/src/widget/row.rs b/native/src/widget/row.rs
index 7dbfb92a..ca1cda23 100644
--- a/native/src/widget/row.rs
+++ b/native/src/widget/row.rs
@@ -1,6 +1,6 @@
 use std::hash::Hash;
 
-use crate::{Element, Event, Hasher, Layout, Node, Point, Style, Widget};
+use crate::{layout, Element, Event, Hasher, Layout, Point, Rectangle, Widget};
 
 /// A container that distributes its contents horizontally.
 pub type Row<'a, Message, Renderer> =
@@ -11,48 +11,20 @@ impl<'a, Message, Renderer> Widget<Message, Renderer>
 where
     Renderer: self::Renderer,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        let mut children: Vec<Node> = self
-            .children
-            .iter()
-            .map(|child| {
-                let mut node = child.widget.node(renderer);
-
-                let mut style = node.0.style();
-                style.margin.end =
-                    stretch::style::Dimension::Points(f32::from(self.spacing));
-
-                node.0.set_style(style);
-                node
-            })
-            .collect();
-
-        if let Some(node) = children.last_mut() {
-            let mut style = node.0.style();
-            style.margin.end = stretch::style::Dimension::Undefined;
-
-            node.0.set_style(style);
-        }
-
-        let mut style = Style::default()
-            .width(self.width)
-            .height(self.height)
-            .max_width(self.max_width)
-            .max_height(self.max_height)
-            .padding(self.padding)
-            .align_self(self.align_self)
-            .align_items(self.align_items)
-            .justify_content(self.justify_content);
-
-        style.0.flex_direction = stretch::style::FlexDirection::Row;
-
-        Node::with_children(style, children)
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        // TODO
+        Layout::new(Rectangle {
+            x: 0.0,
+            y: 0.0,
+            width: 0.0,
+            height: 0.0,
+        })
     }
 
     fn on_event(
         &mut self,
         event: Event,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
         messages: &mut Vec<Message>,
         renderer: &Renderer,
@@ -73,7 +45,7 @@ where
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Renderer::Output {
         renderer.draw(&self, layout, cursor_position)
@@ -101,7 +73,7 @@ pub trait Renderer: crate::Renderer + Sized {
     fn draw<Message>(
         &mut self,
         row: &Row<'_, Message, Self>,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Self::Output;
 }
diff --git a/native/src/widget/scrollable.rs b/native/src/widget/scrollable.rs
index de4c749c..a5eb2f01 100644
--- a/native/src/widget/scrollable.rs
+++ b/native/src/widget/scrollable.rs
@@ -1,7 +1,7 @@
 use crate::{
     column,
     input::{mouse, ButtonState},
-    Element, Event, Hasher, Layout, Node, Point, Rectangle, Style, Widget,
+    layout, Element, Event, Hasher, Layout, Point, Rectangle, Widget,
 };
 
 pub use iced_core::scrollable::State;
@@ -19,32 +19,15 @@ impl<'a, Message, Renderer> Widget<Message, Renderer>
 where
     Renderer: self::Renderer + column::Renderer,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        let mut content = self.content.node(renderer);
-
-        {
-            let mut style = content.0.style();
-            style.flex_shrink = 0.0;
-
-            content.0.set_style(style);
-        }
-
-        let mut style = Style::default()
-            .width(self.content.width)
-            .max_width(self.content.max_width)
-            .height(self.height)
-            .max_height(self.max_height)
-            .align_self(self.align_self);
-
-        style.0.flex_direction = stretch::style::FlexDirection::Column;
-
-        Node::with_children(style, vec![content])
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        // TODO
+        self.content.layout(renderer, limits)
     }
 
     fn on_event(
         &mut self,
         event: Event,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
         messages: &mut Vec<Message>,
         renderer: &Renderer,
@@ -147,7 +130,7 @@ where
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Renderer::Output {
         let bounds = layout.bounds();
@@ -185,7 +168,7 @@ pub trait Renderer: crate::Renderer + Sized {
         &mut self,
         scrollable: &Scrollable<'_, Message, Self>,
         bounds: Rectangle,
-        content_layout: Layout<'_>,
+        content_layout: &Layout,
         cursor_position: Point,
     ) -> Self::Output;
 }
diff --git a/native/src/widget/slider.rs b/native/src/widget/slider.rs
index be2b9b22..be4ed564 100644
--- a/native/src/widget/slider.rs
+++ b/native/src/widget/slider.rs
@@ -7,7 +7,7 @@
 use std::hash::Hash;
 
 use crate::input::{mouse, ButtonState};
-use crate::{Element, Event, Hasher, Layout, Node, Point, Widget};
+use crate::{layout, Element, Event, Hasher, Layout, Point, Widget};
 
 pub use iced_core::slider::*;
 
@@ -15,14 +15,14 @@ impl<'a, Message, Renderer> Widget<Message, Renderer> for Slider<'a, Message>
 where
     Renderer: self::Renderer,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        renderer.node(&self)
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        renderer.layout(&self, limits)
     }
 
     fn on_event(
         &mut self,
         event: Event,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
         messages: &mut Vec<Message>,
         _renderer: &Renderer,
@@ -70,7 +70,7 @@ where
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Renderer::Output {
         renderer.draw(&self, layout, cursor_position)
@@ -93,7 +93,11 @@ pub trait Renderer: crate::Renderer {
     ///
     /// [`Node`]: ../../struct.Node.html
     /// [`Radio`]: struct.Radio.html
-    fn node<Message>(&self, slider: &Slider<'_, Message>) -> Node;
+    fn layout<Message>(
+        &self,
+        slider: &Slider<'_, Message>,
+        limits: &layout::Limits,
+    ) -> Layout;
 
     /// Draws a [`Slider`].
     ///
@@ -110,7 +114,7 @@ pub trait Renderer: crate::Renderer {
     fn draw<Message>(
         &mut self,
         slider: &Slider<'_, Message>,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Self::Output;
 }
diff --git a/native/src/widget/text.rs b/native/src/widget/text.rs
index e389e1d9..da8563a4 100644
--- a/native/src/widget/text.rs
+++ b/native/src/widget/text.rs
@@ -1,5 +1,5 @@
 //! Write some text for your users to read.
-use crate::{Element, Hasher, Layout, Node, Point, Widget};
+use crate::{layout, Element, Hasher, Layout, Point, Widget};
 
 use std::hash::Hash;
 
@@ -9,14 +9,14 @@ impl<Message, Renderer> Widget<Message, Renderer> for Text
 where
     Renderer: self::Renderer,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        renderer.node(&self)
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        renderer.layout(&self, limits)
     }
 
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         _cursor_position: Point,
     ) -> Renderer::Output {
         renderer.draw(&self, layout)
@@ -49,7 +49,7 @@ pub trait Renderer: crate::Renderer {
     /// [`Style`]: ../../struct.Style.html
     /// [`Text`]: struct.Text.html
     /// [`Node::with_measure`]: ../../struct.Node.html#method.with_measure
-    fn node(&self, text: &Text) -> Node;
+    fn layout(&self, text: &Text, limits: &layout::Limits) -> Layout;
 
     /// Draws a [`Text`] fragment.
     ///
@@ -64,7 +64,7 @@ pub trait Renderer: crate::Renderer {
     /// [`Text`]: struct.Text.html
     /// [`HorizontalAlignment`]: enum.HorizontalAlignment.html
     /// [`VerticalAlignment`]: enum.VerticalAlignment.html
-    fn draw(&mut self, text: &Text, layout: Layout<'_>) -> Self::Output;
+    fn draw(&mut self, text: &Text, layout: &Layout) -> Self::Output;
 }
 
 impl<'a, Message, Renderer> From<Text> for Element<'a, Message, Renderer>
diff --git a/native/src/widget/text_input.rs b/native/src/widget/text_input.rs
index d9837b61..ca72801d 100644
--- a/native/src/widget/text_input.rs
+++ b/native/src/widget/text_input.rs
@@ -1,7 +1,6 @@
 use crate::{
     input::{keyboard, mouse, ButtonState},
-    Element, Event, Hasher, Layout, Length, Node, Point, Rectangle, Style,
-    Widget,
+    layout, Element, Event, Hasher, Layout, Point, Rectangle, Widget,
 };
 
 pub use iced_core::{text_input::State, TextInput};
@@ -11,25 +10,20 @@ where
     Renderer: self::Renderer,
     Message: Clone + std::fmt::Debug,
 {
-    fn node(&self, renderer: &Renderer) -> Node {
-        let text_bounds =
-            Node::new(Style::default().width(Length::Fill).height(
-                Length::Units(self.size.unwrap_or(renderer.default_size())),
-            ));
-
-        Node::with_children(
-            Style::default()
-                .width(self.width)
-                .max_width(self.width)
-                .padding(self.padding),
-            vec![text_bounds],
-        )
+    fn layout(&self, renderer: &Renderer, limits: &layout::Limits) -> Layout {
+        // TODO
+        Layout::new(Rectangle {
+            x: 0.0,
+            y: 0.0,
+            width: 0.0,
+            height: 0.0,
+        })
     }
 
     fn on_event(
         &mut self,
         event: Event,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
         messages: &mut Vec<Message>,
         _renderer: &Renderer,
@@ -101,7 +95,7 @@ where
     fn draw(
         &self,
         renderer: &mut Renderer,
-        layout: Layout<'_>,
+        layout: &Layout,
         cursor_position: Point,
     ) -> Renderer::Output {
         let bounds = layout.bounds();