stack & padding fix sorta, preparing for scroll areas

src/core/pad.rs

@@ -12,8 +12,20 @@ impl Widget for Padded {
 
     fn desired_size(&mut self, ctx: &mut SizeCtx) -> UiVec2 {
         let mut size = ctx.size(&self.inner);
+        // TODO: this is currently a hack
+        // the correct solution is that the position is not linear
+        // becauase if you have 0.5 rel + 100 abs, it's linear
+        // until you fill up parent rel (in abs units) and then 1.0 rel (piecewise linear)
+        // so I guess yet another detection system is needed
+        // to determine when abs translated to rel + rel > 1.0
+        // hopefully find a way to get working on gpu so no cpu changing needed
+        // eg by sending size to calculate above and then doing... something?
+        if size.rel.x != 1.0 {
             size.abs.x += self.padding.left + self.padding.right;
+        }
+        if size.rel.y != 1.0 {
             size.abs.y += self.padding.top + self.padding.bottom;
+        }
         size
     }
 }

src/core/span.rs

@@ -47,7 +47,7 @@ impl Widget for Span {
         } else {
             UiScalar::new(total.rel, total.abs)
         };
-        let mut max_ortho = UiScalar::default();
+        let mut max_ortho = UiScalar::ZERO;
         for (child, _) in &self.children {
             let size = ctx.size(child);
             max_ortho = max_ortho.max(size.axis(!self.dir.axis));

src/core/stack.rs

@@ -1,19 +1,82 @@
+use std::marker::PhantomData;
+
 use crate::prelude::*;
 
 pub struct Stack {
     pub children: Vec<WidgetId>,
+    pub size: StackSize,
+    pub offset: usize,
 }
 
 impl Widget for Stack {
     fn draw(&mut self, painter: &mut Painter) {
-        let base = painter.layer;
+        for _ in 0..self.offset {
-        for child in &self.children {
-            if painter.layer == base {
-                painter.layer = painter.child_layer();
-            } else {
             painter.layer = painter.next_layer();
         }
+        let base = painter.layer;
+        for child in &self.children {
+            painter.layer = if painter.layer == base {
+                painter.child_layer()
+            } else {
+                painter.next_layer()
+            };
             painter.widget(child);
         }
     }
+
+    fn desired_size(&mut self, ctx: &mut SizeCtx) -> UiVec2 {
+        match self.size {
+            StackSize::Full => UiVec2::MAX_SIZE,
+            StackSize::Child(i) => ctx.size(&self.children[i]),
+        }
+    }
+}
+
+#[derive(Default, Debug)]
+pub enum StackSize {
+    #[default]
+    Full,
+    Child(usize),
+}
+
+pub struct StackBuilder<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> {
+    pub children: Wa,
+    pub size: StackSize,
+    pub offset: usize,
+    _pd: PhantomData<Tag>,
+}
+
+impl<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> FnOnce<(&mut Ui,)>
+    for StackBuilder<LEN, Wa, Tag>
+{
+    type Output = Stack;
+
+    extern "rust-call" fn call_once(self, args: (&mut Ui,)) -> Self::Output {
+        Stack {
+            children: self.children.ui(args.0).arr.to_vec(),
+            offset: self.offset,
+            size: self.size,
+        }
+    }
+}
+
+impl<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> StackBuilder<LEN, Wa, Tag> {
+    pub fn new(children: Wa) -> Self {
+        Self {
+            children,
+            size: StackSize::default(),
+            offset: 0,
+            _pd: PhantomData,
+        }
+    }
+
+    pub fn stack_size(mut self, size: StackSize) -> Self {
+        self.size = size;
+        self
+    }
+
+    pub fn offset_layer(mut self, offset: usize) -> Self {
+        self.offset = offset;
+        self
+    }
 }

src/core/trait_fns.rs

@@ -44,12 +44,12 @@ impl<W: WidgetLike<Tag>, Tag> CoreWidget<W::Widget, Tag> for W {
     }
 }
 
-pub trait CoreWidgetArr<const LEN: usize, Tag> {
+pub trait CoreWidgetArr<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> {
     fn span(self, dir: Dir, lengths: impl IntoSpanLens<LEN>) -> impl WidgetFn<Span>;
-    fn stack(self) -> impl WidgetFn<Stack>;
+    fn stack(self) -> StackBuilder<LEN, Wa, Tag>;
 }
 
-impl<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> CoreWidgetArr<LEN, Tag> for Wa {
+impl<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> CoreWidgetArr<LEN, Wa, Tag> for Wa {
     fn span(self, dir: Dir, lengths: impl IntoSpanLens<LEN>) -> impl WidgetFn<Span> {
         let lengths = lengths.into_lens();
         move |ui| Span {
@@ -57,10 +57,8 @@ impl<const LEN: usize, Wa: WidgetArrLike<LEN, Tag>, Tag> CoreWidgetArr<LEN, Tag>
             dir,
         }
     }
-    fn stack(self) -> impl WidgetFn<Stack> {
+    fn stack(self) -> StackBuilder<LEN, Wa, Tag> {
-        move |ui| Stack {
+        StackBuilder::new(self)
-            children: self.ui(ui).arr.to_vec(),
-        }
     }
 }
 

src/layout/layer.rs

@@ -27,6 +27,8 @@ enum Ptr {
 /// is that realistically desired?
 pub struct Layers {
     vec: Vec<LayerNode>,
+    /// index of last layer at top level (start at first = 0)
+    last: usize,
 }
 
 /// TODO: this can be replaced with Primitives itself atm
@@ -45,6 +47,7 @@ impl Layers {
     pub fn new() -> Layers {
         Self {
             vec: vec![LayerNode::head()],
+            last: 0,
         }
     }
 
@@ -73,7 +76,7 @@ impl Layers {
         match self.vec[i_new].next {
             Ptr::Next(i) => self.vec[i].prev = Ptr::Next(i_new),
             Ptr::Parent(i) => self.vec[i].child.as_mut().unwrap().tail = i_new,
-            Ptr::None => (),
+            Ptr::None => self.last = i_new,
         }
         i_new
     }
@@ -95,11 +98,15 @@ impl Layers {
     }
 
     pub fn iter_mut(&mut self) -> LayerIteratorMut<'_> {
-        LayerIteratorMut::new(&mut self.vec)
+        LayerIteratorMut::new(&mut self.vec, self.last)
+    }
+
+    pub fn iter(&self) -> impl Iterator<Item = (usize, &Layer)> {
+        self.indices().map(|i| (i, &self.vec[i].data))
     }
 
     pub fn indices(&self) -> LayerIndexIterator<'_> {
-        LayerIndexIterator::new(&self.vec)
+        LayerIndexIterator::new(&self.vec, self.last)
     }
 
     pub fn write<P: Primitive>(
@@ -179,9 +186,9 @@ impl<'a> DoubleEndedIterator for LayerIteratorMut<'a> {
 }
 
 impl<'a> LayerIteratorMut<'a> {
-    fn new(vec: &'a mut Vec<LayerNode>) -> Self {
+    fn new(vec: &'a mut Vec<LayerNode>, last: usize) -> Self {
         Self {
-            inner: LayerIndexIterator::new(vec),
+            inner: LayerIndexIterator::new(vec, last),
         }
     }
 }
@@ -203,7 +210,10 @@ impl<'a> Iterator for LayerIndexIterator<'a> {
         } else if let Ptr::Next(i) = node.next {
             Some(i)
         } else if let Ptr::Parent(i) = node.next {
-            let node = &self.vec[i];
+            let mut node = &self.vec[i];
+            while let Ptr::Parent(i) = node.next {
+                node = &self.vec[i];
+            }
             if let Ptr::Next(i) = node.next {
                 Some(i)
             } else {
@@ -243,8 +253,8 @@ impl<'a> DoubleEndedIterator for LayerIndexIterator<'a> {
 }
 
 impl<'a> LayerIndexIterator<'a> {
-    fn new(vec: &'a Vec<LayerNode>) -> Self {
+    fn new(vec: &'a Vec<LayerNode>, last: usize) -> Self {
-        let mut last = 0;
+        let mut last = last;
         while let Some(c) = vec[last].child {
             last = c.tail;
         }

src/layout/painter.rs

@@ -69,11 +69,21 @@ impl<'a> PainterCtx<'a> {
         };
 
         if let Some((rid, size)) = &active.resize {
+            let checked = &mut HashMap::default();
+            let mut ctx = SizeCtx {
+                checked,
+                text: self.text,
+                textures: self.textures,
+                widgets: self.widgets,
+            };
+            let desired = ctx.size_inner(id);
+            if *size != desired {
                 self.redraw(&rid.duplicate());
                 if self.drawing.contains(id) {
                     return;
                 }
             }
+        }
 
         let Some(active) = self.remove(id) else {
             return;
@@ -298,14 +308,17 @@ pub struct SizeCtx<'a> {
 }
 
 impl SizeCtx<'_> {
+    fn size_inner(&mut self, id: &Id) -> UiVec2 {
+        let size = self.widgets.get_dyn_dynamic(id).desired_size(self);
+        self.checked.insert(id.duplicate(), size);
+        size
+    }
     pub fn size<W>(&mut self, id: &WidgetId<W>) -> UiVec2 {
         // TODO: determine if this is useful
         // if let Some(size) = self.checked.get(&id.id) {
         //     return Some(*size);
         // }
-        let size = self.widgets.get_dyn_dynamic(&id.id).desired_size(self);
+        self.size_inner(&id.id)
-        self.checked.insert(id.id.duplicate(), size);
-        size
     }
     pub fn draw_text(
         &mut self,

src/layout/pos.rs

@@ -100,9 +100,7 @@ impl UiVec2 {
         self.rel * size + self.abs
     }
 
-    pub const fn max_size() -> Self {
+    pub const MAX_SIZE: Self = Self::rel(Vec2::ONE);
-        Self::rel(Vec2::ONE)
-    }
 
     pub const fn from_axis(axis: Axis, aligned: UiScalar, ortho: UiScalar) -> Self {
         Self {
@@ -134,6 +132,8 @@ impl_op!(UiScalar Add add; rel abs);
 impl_op!(UiScalar Sub sub; rel abs);
 
 impl UiScalar {
+    pub const ZERO: Self = Self { rel: 0.0, abs: 0.0 };
+
     pub fn new(rel: f32, abs: f32) -> Self {
         Self { rel, abs }
     }

src/layout/widget.rs

@@ -5,7 +5,7 @@ use std::{any::Any, marker::PhantomData};
 pub trait Widget: Any {
     fn draw(&mut self, painter: &mut Painter);
     fn desired_size(&mut self, _: &mut SizeCtx) -> UiVec2 {
-        UiVec2::max_size()
+        UiVec2::MAX_SIZE
     }
 }
 
@@ -76,7 +76,7 @@ impl<const LEN: usize, Ws> WidgetArr<LEN, Ws> {
 }
 
 pub struct ArrTag;
-pub trait WidgetArrLike<const LEN: usize, Tags> {
+pub trait WidgetArrLike<const LEN: usize, Tag> {
     type Ws;
     fn ui(self, ui: &mut Ui) -> WidgetArr<LEN, Self::Ws>;
 }

src/testing/mod.rs

@@ -138,17 +138,22 @@ impl Client {
                 let content = client.ui.text(id).take();
                 let text = text_edit(content)
                     .font_size(30)
+                    .text_align(Align::Left)
                     .id_on(Sense::click(), |id, client: &mut Client, ctx| {
                         client.ui.text(id).select(ctx.cursor, ctx.size);
                         client.focus = Some(id.clone());
-                    })
+                    });
-                    .pad(10)
+                let msg_box = (rect(Color::WHITE.darker(0.5)), text)
+                    .stack()
+                    .stack_size(StackSize::Child(1))
                     .add(&mut client.ui);
-                client.ui[texts].children.push((text.any(), sized()));
+                client.ui[texts].children.push((msg_box.any(), sized()));
             })
             .add(&mut ui);
         let text_edit_scroll = (
             (Rect::new(Color::SKY), texts).stack(),
+            (
+                Rect::new(Color::WHITE.darker(0.9)),
                 (
                     add_text.clone(),
                     Rect::new(Color::GREEN)
@@ -158,7 +163,12 @@ impl Client {
                         .size(40),
                 )
                     .span(Dir::RIGHT, [ratio(1), sized()])
-                .pad(30),
+                    .pad(10),
+            )
+                .stack()
+                .stack_size(StackSize::Child(1))
+                .offset_layer(1)
+                .align(Align::Bot),
         )
             .span(Dir::DOWN, [ratio(1), sized()])
             .add_static(&mut ui);
@@ -192,7 +202,7 @@ impl Client {
             .span(Dir::RIGHT, ratio(1));
 
         let info = text("").add(&mut ui);
-        let info_sect = info.clone().pad(10).align(Align::BotLeft);
+        let info_sect = info.clone().pad(10).align(Align::Right);
 
         (
             (tabs, main).span(Dir::DOWN, [fixed(40), ratio(1)]),