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-rw-r--r--src/library/stack.rs261
1 files changed, 0 insertions, 261 deletions
diff --git a/src/library/stack.rs b/src/library/stack.rs
deleted file mode 100644
index 8e463f6a..00000000
--- a/src/library/stack.rs
+++ /dev/null
@@ -1,261 +0,0 @@
-//! Side-by-side layout of nodes along an axis.
-
-use super::prelude::*;
-use super::{AlignNode, SpacingKind};
-
-/// Arrange nodes and spacing along an axis.
-#[derive(Debug, Hash)]
-pub struct StackNode {
- /// The stacking direction.
- pub dir: Dir,
- /// The spacing between non-spacing children.
- pub spacing: Option<SpacingKind>,
- /// The children to be stacked.
- pub children: Vec<StackChild>,
-}
-
-#[class]
-impl StackNode {
- fn construct(_: &mut Context, args: &mut Args) -> TypResult<Template> {
- Ok(Template::block(Self {
- dir: args.named("dir")?.unwrap_or(Dir::TTB),
- spacing: args.named("spacing")?,
- children: args.all()?,
- }))
- }
-}
-
-impl Layout for StackNode {
- fn layout(
- &self,
- ctx: &mut Context,
- regions: &Regions,
- styles: StyleChain,
- ) -> TypResult<Vec<Arc<Frame>>> {
- let mut layouter = StackLayouter::new(self.dir, regions);
-
- // Spacing to insert before the next node.
- let mut deferred = None;
-
- for child in &self.children {
- match child {
- StackChild::Spacing(kind) => {
- layouter.layout_spacing(*kind);
- deferred = None;
- }
- StackChild::Node(node) => {
- if let Some(kind) = deferred {
- layouter.layout_spacing(kind);
- }
-
- layouter.layout_node(ctx, node, styles)?;
- deferred = self.spacing;
- }
- }
- }
-
- Ok(layouter.finish())
- }
-}
-
-/// A child of a stack node.
-#[derive(Hash)]
-pub enum StackChild {
- /// Spacing between other nodes.
- Spacing(SpacingKind),
- /// An arbitrary node.
- Node(LayoutNode),
-}
-
-impl Debug for StackChild {
- fn fmt(&self, f: &mut Formatter) -> fmt::Result {
- match self {
- Self::Spacing(kind) => kind.fmt(f),
- Self::Node(node) => node.fmt(f),
- }
- }
-}
-
-castable! {
- StackChild,
- Expected: "linear, fractional or template",
- Value::Length(v) => Self::Spacing(SpacingKind::Linear(v.into())),
- Value::Relative(v) => Self::Spacing(SpacingKind::Linear(v.into())),
- Value::Linear(v) => Self::Spacing(SpacingKind::Linear(v)),
- Value::Fractional(v) => Self::Spacing(SpacingKind::Fractional(v)),
- Value::Template(v) => Self::Node(v.pack()),
-}
-
-/// Performs stack layout.
-pub struct StackLayouter {
- /// The stacking direction.
- dir: Dir,
- /// The axis of the stacking direction.
- axis: SpecAxis,
- /// The regions to layout children into.
- regions: Regions,
- /// Whether the stack itself should expand to fill the region.
- expand: Spec<bool>,
- /// The full size of the current region that was available at the start.
- full: Size,
- /// The generic size used by the frames for the current region.
- used: Gen<Length>,
- /// The sum of fractional ratios in the current region.
- fr: Fractional,
- /// Already layouted items whose exact positions are not yet known due to
- /// fractional spacing.
- items: Vec<StackItem>,
- /// Finished frames for previous regions.
- finished: Vec<Arc<Frame>>,
-}
-
-/// A prepared item in a stack layout.
-enum StackItem {
- /// Absolute spacing between other items.
- Absolute(Length),
- /// Fractional spacing between other items.
- Fractional(Fractional),
- /// A frame for a layouted child node.
- Frame(Arc<Frame>, Align),
-}
-
-impl StackLayouter {
- /// Create a new stack layouter.
- pub fn new(dir: Dir, regions: &Regions) -> Self {
- let axis = dir.axis();
- let expand = regions.expand;
- let full = regions.first;
-
- // Disable expansion along the block axis for children.
- let mut regions = regions.clone();
- regions.expand.set(axis, false);
-
- Self {
- dir,
- axis,
- regions,
- expand,
- full,
- used: Gen::zero(),
- fr: Fractional::zero(),
- items: vec![],
- finished: vec![],
- }
- }
-
- /// Add spacing along the spacing direction.
- pub fn layout_spacing(&mut self, spacing: SpacingKind) {
- match spacing {
- SpacingKind::Linear(v) => {
- // Resolve the linear and limit it to the remaining space.
- let resolved = v.resolve(self.regions.base.get(self.axis));
- let remaining = self.regions.first.get_mut(self.axis);
- let limited = resolved.min(*remaining);
- *remaining -= limited;
- self.used.main += limited;
- self.items.push(StackItem::Absolute(resolved));
- }
- SpacingKind::Fractional(v) => {
- self.fr += v;
- self.items.push(StackItem::Fractional(v));
- }
- }
- }
-
- /// Layout an arbitrary node.
- pub fn layout_node(
- &mut self,
- ctx: &mut Context,
- node: &LayoutNode,
- styles: StyleChain,
- ) -> TypResult<()> {
- if self.regions.is_full() {
- self.finish_region();
- }
-
- // Align nodes' block-axis alignment is respected by the stack node.
- let align = node
- .downcast::<AlignNode>()
- .and_then(|node| node.aligns.get(self.axis))
- .unwrap_or(self.dir.start().into());
-
- let frames = node.layout(ctx, &self.regions, styles)?;
- let len = frames.len();
- for (i, frame) in frames.into_iter().enumerate() {
- // Grow our size, shrink the region and save the frame for later.
- let size = frame.size.to_gen(self.axis);
- self.used.main += size.main;
- self.used.cross.set_max(size.cross);
- *self.regions.first.get_mut(self.axis) -= size.main;
- self.items.push(StackItem::Frame(frame, align));
-
- if i + 1 < len {
- self.finish_region();
- }
- }
-
- Ok(())
- }
-
- /// Advance to the next region.
- pub fn finish_region(&mut self) {
- // Determine the size of the stack in this region dependening on whether
- // the region expands.
- let used = self.used.to_spec(self.axis);
- let mut size = self.expand.select(self.full, used);
-
- // Expand fully if there are fr spacings.
- let full = self.full.get(self.axis);
- let remaining = full - self.used.main;
- if self.fr.get() > 0.0 && full.is_finite() {
- self.used.main = full;
- size.set(self.axis, full);
- }
-
- let mut output = Frame::new(size);
- let mut cursor = Length::zero();
- let mut ruler: Align = self.dir.start().into();
-
- // Place all frames.
- for item in self.items.drain(..) {
- match item {
- StackItem::Absolute(v) => cursor += v,
- StackItem::Fractional(v) => cursor += v.resolve(self.fr, remaining),
- StackItem::Frame(frame, align) => {
- if self.dir.is_positive() {
- ruler = ruler.max(align);
- } else {
- ruler = ruler.min(align);
- }
-
- // Align along the block axis.
- let parent = size.get(self.axis);
- let child = frame.size.get(self.axis);
- let block = ruler.resolve(parent - self.used.main)
- + if self.dir.is_positive() {
- cursor
- } else {
- self.used.main - child - cursor
- };
-
- let pos = Gen::new(Length::zero(), block).to_point(self.axis);
- cursor += child;
- output.push_frame(pos, frame);
- }
- }
- }
-
- // Advance to the next region.
- self.regions.next();
- self.full = self.regions.first;
- self.used = Gen::zero();
- self.fr = Fractional::zero();
- self.finished.push(Arc::new(output));
- }
-
- /// Finish layouting and return the resulting frames.
- pub fn finish(mut self) -> Vec<Arc<Frame>> {
- self.finish_region();
- self.finished
- }
-}
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