Introduce page / block / inline levels

1 files changed, 18 insertions, 46 deletions

diff --git a/src/layout/shape.rs b/src/layout/shape.rs
index 3469f660..13d5418f 100644
--- a/src/layout/shape.rs
+++ b/src/layout/shape.rs
@@ -1,6 +1,7 @@
 use std::f64::consts::SQRT_2;
 
 use super::*;
+use crate::util::RcExt;
 
 /// Places its child into a sizable and fillable shape.
 #[derive(Debug)]
@@ -15,7 +16,7 @@ pub struct ShapeNode {
     /// How to fill the shape, if at all.
     pub fill: Option<Paint>,
     /// The child node to place into the shape, if any.
-    pub child: Option<LayoutNode>,
+    pub child: Option<BlockNode>,
 }
 
 /// The type of a shape.
@@ -31,40 +32,15 @@ pub enum ShapeKind {
     Ellipse,
 }
 
-impl Layout for ShapeNode {
-    fn layout(
-        &self,
-        ctx: &mut LayoutContext,
-        regions: &Regions,
-    ) -> Vec<Constrained<Rc<Frame>>> {
+impl InlineLevel for ShapeNode {
+    fn layout(&self, ctx: &mut LayoutContext, space: Length, base: Size) -> Frame {
         // Resolve width and height relative to the region's base.
-        let width = self.width.map(|w| w.resolve(regions.base.w));
-        let height = self.height.map(|h| h.resolve(regions.base.h));
-
-        // Generate constraints.
-        let constraints = {
-            let mut cts = Constraints::new(regions.expand);
-            cts.set_base_if_linear(regions.base, Spec::new(self.width, self.height));
-
-            // Set tight exact and base constraints if the child is
-            // automatically sized since we don't know what the child might do.
-            if self.width.is_none() {
-                cts.exact.x = Some(regions.current.w);
-                cts.base.x = Some(regions.base.w);
-            }
-
-            // Same here.
-            if self.height.is_none() {
-                cts.exact.y = Some(regions.current.h);
-                cts.base.y = Some(regions.base.h);
-            }
-
-            cts
-        };
+        let width = self.width.map(|w| w.resolve(base.w));
+        let height = self.height.map(|h| h.resolve(base.h));
 
         // Layout.
-        let mut frames = if let Some(child) = &self.child {
-            let mut node: &dyn Layout = child;
+        let mut frame = if let Some(child) = &self.child {
+            let mut node: &dyn BlockLevel = child;
 
             let padded;
             if matches!(self.shape, ShapeKind::Circle | ShapeKind::Ellipse) {
@@ -79,14 +55,12 @@ impl Layout for ShapeNode {
 
             // The "pod" is the region into which the child will be layouted.
             let mut pod = {
-                let size = Size::new(
-                    width.unwrap_or(regions.current.w),
-                    height.unwrap_or(regions.current.h),
-                );
+                let size =
+                    Size::new(width.unwrap_or(space), height.unwrap_or(Length::inf()));
 
                 let base = Size::new(
-                    if width.is_some() { size.w } else { regions.base.w },
-                    if height.is_some() { size.h } else { regions.base.h },
+                    if width.is_some() { size.w } else { base.w },
+                    if height.is_some() { size.h } else { base.h },
                 );
 
                 let expand = Spec::new(width.is_some(), height.is_some());
@@ -108,17 +82,15 @@ impl Layout for ShapeNode {
 
             // Validate and set constraints.
             assert_eq!(frames.len(), 1);
-            frames[0].constraints = constraints;
-            frames
+            Rc::take(frames.into_iter().next().unwrap().item)
         } else {
             // Resolve shape size.
             let size = Size::new(width.unwrap_or_default(), height.unwrap_or_default());
-            vec![Frame::new(size, size.h).constrain(constraints)]
+            Frame::new(size, size.h)
         };
 
         // Add background shape if desired.
         if let Some(fill) = self.fill {
-            let frame = Rc::make_mut(&mut frames[0].item);
             let (pos, geometry) = match self.shape {
                 ShapeKind::Square | ShapeKind::Rect => {
                     (Point::zero(), Geometry::Rect(frame.size))
@@ -131,12 +103,12 @@ impl Layout for ShapeNode {
             frame.prepend(pos, Element::Geometry(geometry, fill));
         }
 
-        frames
+        frame
     }
 }
 
-impl From<ShapeNode> for LayoutNode {
-    fn from(shape: ShapeNode) -> Self {
-        Self::new(shape)
+impl From<ShapeNode> for InlineNode {
+    fn from(node: ShapeNode) -> Self {
+        Self::new(node)
     }
 }