finished moving out render_state

core/src/attr.rs

@@ -1,15 +1,15 @@
-use crate::{HasUi, WidgetIdFn, WidgetLike, WidgetRef};
+use crate::{UiRsc, WidgetIdFn, WidgetLike, WeakWidget};
 
 pub trait WidgetAttr<Rsc, W: ?Sized> {
     type Input;
-    fn run(rsc: &mut Rsc, id: WidgetRef<W>, input: Self::Input);
+    fn run(rsc: &mut Rsc, id: WeakWidget<W>, input: Self::Input);
 }
 
 pub trait Attrable<Rsc, W: ?Sized, Tag> {
     fn attr<A: WidgetAttr<Rsc, W>>(self, input: A::Input) -> impl WidgetIdFn<Rsc, W>;
 }
 
-impl<Rsc: HasUi, WL: WidgetLike<Rsc, Tag>, Tag> Attrable<Rsc, WL::Widget, Tag> for WL {
+impl<Rsc: UiRsc, WL: WidgetLike<Rsc, Tag>, Tag> Attrable<Rsc, WL::Widget, Tag> for WL {
     fn attr<A: WidgetAttr<Rsc, WL::Widget>>(
         self,
         input: A::Input,

core/src/event/ctx.rs

@@ -1,4 +1,4 @@
-use crate::{HasEvents, HasUi, Widget, WidgetRef};
+use crate::{HasEvents, WeakWidget, Widget};
 
 pub struct EventCtx<'a, Rsc: HasEvents, Data> {
     pub state: &'a mut Rsc::State,
@@ -6,13 +6,13 @@ pub struct EventCtx<'a, Rsc: HasEvents, Data> {
 }
 
 pub struct EventIdCtx<'a, Rsc: HasEvents, Data, W: ?Sized> {
-    pub widget: WidgetRef<W>,
+    pub widget: WeakWidget<W>,
     pub state: &'a mut Rsc::State,
     pub data: Data,
 }
 
-impl<Rsc: HasEvents + HasUi, Data, W: Widget> EventIdCtx<'_, Rsc, Data, W> {
+impl<Rsc: HasEvents, Data, W: Widget> EventIdCtx<'_, Rsc, Data, W> {
     pub fn widget<'a>(&self, rsc: &'a mut Rsc) -> &'a mut W {
-        &mut rsc.ui_mut()[self.widget]
+        &mut rsc.ui_mut().widgets[self.widget]
     }
 }

core/src/event/manager.rs

@@ -1,6 +1,6 @@
 use crate::{
     ActiveData, Event, EventCtx, EventFn, EventIdCtx, EventLike, HasEvents, IdLike, LayerId,
-    Widget, WidgetEventFn, WidgetId, WidgetRef,
+    WeakWidget, Widget, WidgetEventFn, WidgetId,
     util::{HashMap, HashSet, TypeMap},
 };
 use std::{any::TypeId, rc::Rc};
@@ -26,9 +26,9 @@ impl<Rsc: HasEvents + 'static> EventManager<Rsc> {
 
     pub fn register<W: Widget + ?Sized, E: EventLike>(
         &mut self,
-        id: WidgetRef<W>,
+        id: WeakWidget<W>,
         event: E,
-        f: impl WidgetEventFn<Rsc, <E::Event as Event>::Data, W>,
+        f: impl for<'a> WidgetEventFn<Rsc, <E::Event as Event>::Data<'a>, W>,
     ) {
         self.get_type::<E>().register(id, event, f);
         self.widget_to_types
@@ -74,7 +74,7 @@ pub trait EventManagerLike<State> {
     fn undraw(&mut self, data: &ActiveData);
 }
 
-type EventData<Rsc, E> = (E, Rc<dyn EventFn<Rsc, <E as Event>::Data>>);
+type EventData<Rsc, E> = (E, Rc<dyn for<'a> EventFn<Rsc, <E as Event>::Data<'a>>>);
 pub struct TypeEventManager<Rsc: HasEvents, E: Event> {
     // TODO: reduce visiblity!!
     pub active: HashMap<LayerId, HashMap<WidgetId, E::State>>,
@@ -114,9 +114,9 @@ impl<Rsc: HasEvents, E: Event> Default for TypeEventManager<Rsc, E> {
 impl<Rsc: HasEvents + 'static, E: Event> TypeEventManager<Rsc, E> {
     fn register<W: Widget + ?Sized>(
         &mut self,
-        widget: WidgetRef<W>,
+        widget: WeakWidget<W>,
         event: impl EventLike<Event = E>,
-        f: impl WidgetEventFn<Rsc, E::Data, W>,
+        f: impl for<'a> WidgetEventFn<Rsc, E::Data<'a>, W>,
     ) {
         let event = event.into_event();
         self.map.entry(widget.id()).or_default().push((
@@ -137,7 +137,7 @@ impl<Rsc: HasEvents + 'static, E: Event> TypeEventManager<Rsc, E> {
     pub fn run_fn<'a>(
         &mut self,
         id: impl IdLike,
-    ) -> impl FnOnce(EventCtx<'_, Rsc, E::Data>, &mut Rsc) + 'a {
+    ) -> impl for<'b> FnOnce(EventCtx<'_, Rsc, E::Data<'b>>, &mut Rsc) + 'a {
         let fs = self.map.get(&id.id()).cloned().unwrap_or_default();
         move |ctx, rsc| {
             for (e, f) in fs {

core/src/event/mod.rs

@@ -7,10 +7,10 @@ pub use manager::*;
 pub use rsc::*;
 
 pub trait Event: Sized + 'static + Clone {
-    type Data: Clone = ();
+    type Data<'a>: Clone = ();
     type State: Default = ();
     #[allow(unused_variables)]
-    fn should_run(&self, data: &Self::Data) -> Option<Self::Data> {
+    fn should_run<'a>(&self, data: &Self::Data<'a>) -> Option<Self::Data<'a>> {
         Some(data.clone())
     }
 }

core/src/event/rsc.rs

@@ -1,20 +1,20 @@
 use crate::{
-    Event, EventCtx, EventLike, EventManager, HasUi, IdLike, Widget, WidgetEventFn, WidgetRef,
+    Event, EventCtx, EventLike, EventManager, IdLike, UiRsc, WeakWidget, Widget, WidgetEventFn,
 };
 
 pub trait HasState: 'static {
     type State;
 }
 
-pub trait HasEvents: Sized + HasUi + HasState {
+pub trait HasEvents: Sized + UiRsc + HasState {
     fn events(&self) -> &EventManager<Self>;
     fn events_mut(&mut self) -> &mut EventManager<Self>;
 
     fn register_event<W: Widget + ?Sized, E: EventLike>(
         &mut self,
-        id: WidgetRef<W>,
+        id: WeakWidget<W>,
         event: E,
-        f: impl WidgetEventFn<Self, <E::Event as Event>::Data, W>,
+        f: impl for<'a> WidgetEventFn<Self, <E::Event as Event>::Data<'a>, W>,
     ) {
         self.events_mut().register(id, event, f);
     }
@@ -24,7 +24,7 @@ pub trait RunEvents: HasEvents {
     fn run_event<E: EventLike>(
         &mut self,
         id: impl IdLike,
-        data: <E::Event as Event>::Data,
+        data: <E::Event as Event>::Data<'_>,
         state: &mut Self::State,
     ) {
         let f = self.events_mut().get_type::<E>().run_fn(id);

core/src/primitive/text.rs

@@ -3,7 +3,7 @@ use cosmic_text::{
     Attrs, AttrsList, Buffer, CacheKey, Color, Family, FontSystem, Metrics, Placement, SwashCache,
     SwashContent,
 };
-use image::{GenericImageView, RgbaImage};
+use image::{DynamicImage, GenericImageView, RgbaImage};
 use std::simd::{Simd, num::SimdUint};
 
 /// TODO: properly wrap this
@@ -185,3 +185,7 @@ pub struct RenderedText {
     pub top_left_offset: Vec2,
     pub size: Vec2,
 }
+
+pub trait HasTextures {
+    fn add_texture(&mut self, image: DynamicImage) -> TextureHandle;
+}

core/src/render/mod.rs

@@ -1,7 +1,7 @@
 use std::num::NonZero;
 
 use crate::{
-    Ui,
+    UiData, UiRenderState,
     render::{data::PrimitiveInstance, texture::GpuTextures, util::ArrBuf},
     util::HashMap,
 };
@@ -59,12 +59,18 @@ impl UiRenderNode {
         }
     }
 
-    pub fn update(&mut self, device: &Device, queue: &Queue, ui: &mut Ui) {
+    pub fn update(
+        &mut self,
+        device: &Device,
+        queue: &Queue,
+        ui: &mut UiData,
+        ui_render: &mut UiRenderState,
+    ) {
         self.active.clear();
-        for (i, primitives) in ui.layers.iter_mut() {
+        for (i, primitives) in ui_render.layers.iter_mut() {
             self.active.push(i);
             for change in primitives.apply_free() {
-                if let Some(inst) = ui.active.get_mut(&change.id) {
+                if let Some(inst) = ui_render.active.get_mut(&change.id) {
                     for h in &mut inst.primitives {
                         if h.layer == i && h.inst_idx == change.old {
                             h.inst_idx = change.new;

core/src/ui/draw_state.rs

@@ -1,46 +1,38 @@
 use crate::{
-    ActiveData, Axis, EventsLike, Painter, SizeCtx, Ui, UiRegion, UiVec2, WidgetId,
+    ActiveData, Axis, EventsLike, Painter, SizeCtx, StrongWidget, UiRegion, UiRenderState, UiVec2,
+    WidgetId, Widgets,
     render::MaskIdx,
     util::{HashSet, forget_ref},
 };
-use std::ops::{Deref, DerefMut};
 
 /// state maintained between widgets during painting
-pub struct DrawState<'a> {
-    pub(super) ui: &'a mut Ui,
+pub struct Drawer<'a> {
+    pub(super) widgets: &'a mut Widgets,
+    pub(super) data: &'a mut PainterData,
     pub(super) events: &'a mut dyn EventsLike,
+    pub(super) render: &'a mut UiRenderState,
+    root: Option<&'a StrongWidget>,
     draw_started: HashSet<WidgetId>,
 }
 
-impl<'a> DrawState<'a> {
-    pub fn new(ui: &'a mut Ui, events: &'a mut dyn EventsLike) -> Self {
-        Self {
-            ui,
-            events,
-            draw_started: Default::default(),
-        }
-    }
-
-    pub fn redraw_updates(&mut self) {
-        while let Some(&id) = self.widgets.needs_redraw.iter().next() {
-            self.redraw(id);
-        }
-        self.ui.free(self.events);
-    }
-
+impl<'a> Drawer<'a> {
     /// redraws a widget that's currently active (drawn)
     pub fn redraw(&mut self, id: WidgetId) {
         self.widgets.needs_redraw.remove(&id);
         self.draw_started.remove(&id);
         // check if parent depends on the desired size of this, if so then redraw it first
         for axis in [Axis::X, Axis::Y] {
-            if let Some(&(outer, old)) = self.cache.size.axis_dyn(axis).get(&id)
-                && let Some(current) = self.active.get(&id)
+            if let Some(&(outer, old)) = self.render.cache.size.axis_dyn(axis).get(&id)
+                && let Some(current) = self.render.active.get(&id)
                 && let Some(pid) = current.parent
             {
-                self.cache.size.axis_dyn(axis).remove(&id);
+                self.render.cache.size.axis_dyn(axis).remove(&id);
                 let new = self.size_ctx(id, outer).len_axis(id, axis);
-                self.cache.size.axis_dyn(axis).insert(id, (outer, new));
+                self.render
+                    .cache
+                    .size
+                    .axis_dyn(axis)
+                    .insert(id, (outer, new));
                 if new != old {
                     self.redraw(pid);
                 }
@@ -68,31 +60,16 @@ impl<'a> DrawState<'a> {
     pub(super) fn size_ctx<'b>(&'b mut self, source: WidgetId, outer: UiVec2) -> SizeCtx<'b> {
         SizeCtx {
             source,
-            cache: &mut self.ui.cache,
-            text: &mut self.ui.text,
-            textures: &mut self.ui.textures,
-            widgets: &self.ui.widgets,
+            cache: &mut self.render.cache,
+            text: &mut self.data.text,
+            textures: &mut self.data.textures,
+            widgets: &self.widgets,
             outer,
-            output_size: self.ui.output_size,
+            output_size: self.render.output_size,
             id: source,
         }
     }
 
-    pub fn redraw_all(&mut self) {
-        // free all resources & cache
-        for (_, active) in self.ui.active.drain() {
-            self.events.undraw(&active);
-        }
-        self.ui.cache.clear();
-        self.ui.free(self.events);
-        self.layers.clear();
-        self.widgets.needs_redraw.clear();
-
-        if let Some(id) = &self.ui.root {
-            self.draw_inner(0, id.id(), UiRegion::FULL, None, MaskIdx::NONE, None);
-        }
-    }
-
     pub(super) fn draw_inner(
         &mut self,
         layer: usize,
@@ -103,8 +80,8 @@ impl<'a> DrawState<'a> {
         old_children: Option<Vec<WidgetId>>,
     ) {
         let mut old_children = old_children.unwrap_or_default();
-        if let Some(active) = self.ui.active.get_mut(&id)
-            && !self.ui.widgets.needs_redraw.contains(&id)
+        if let Some(active) = self.render.active.get_mut(&id)
+            && !self.widgets.needs_redraw.contains(&id)
         {
             // check to see if we can skip drawing first
             if active.region == region {
@@ -124,7 +101,7 @@ impl<'a> DrawState<'a> {
         self.draw_started.insert(id);
 
         let mut painter = Painter {
-            state: self,
+            drawer: self,
             region,
             mask,
             layer,
@@ -134,12 +111,12 @@ impl<'a> DrawState<'a> {
             children: Vec::new(),
         };
 
-        let mut widget = painter.state.widgets.get_dyn_dynamic(id);
+        let mut widget = painter.drawer.widgets.get_dyn_dynamic(id);
         widget.draw(&mut painter);
         drop(widget);
 
         let Painter {
-            state: _,
+            drawer: _,
             region,
             mask,
             textures,
@@ -170,13 +147,13 @@ impl<'a> DrawState<'a> {
 
         // update modules
         self.events.draw(&active);
-        self.active.insert(id, active);
+        self.render.active.insert(id, active);
     }
 
     fn mov(&mut self, id: WidgetId, from: UiRegion, to: UiRegion) {
-        let active = self.ui.active.get_mut(&id).unwrap();
+        let active = self.render.active.get_mut(&id).unwrap();
         for h in &active.primitives {
-            let region = self.ui.layers[h.layer].region_mut(h);
+            let region = self.render.layers[h.layer].region_mut(h);
             *region = region.outside(&from).within(&to);
         }
         active.region = active.region.outside(&from).within(&to);
@@ -189,16 +166,16 @@ impl<'a> DrawState<'a> {
 
     /// NOTE: instance textures are cleared and self.textures freed
     fn remove(&mut self, id: WidgetId, undraw: bool) -> Option<ActiveData> {
-        let mut active = self.active.remove(&id);
+        let mut active = self.render.active.remove(&id);
         if let Some(active) = &mut active {
             for h in &active.primitives {
-                let mask = self.layers.free(h);
+                let mask = self.render.layers.free(h);
                 if mask != MaskIdx::NONE {
-                    self.masks.remove(mask);
+                    self.data.masks.remove(mask);
                 }
             }
             active.textures.clear();
-            self.textures.free();
+            self.data.textures.free();
             if undraw {
                 self.events.undraw(active);
             }
@@ -207,7 +184,7 @@ impl<'a> DrawState<'a> {
     }
 
     fn remove_rec(&mut self, id: WidgetId) -> Option<ActiveData> {
-        self.cache.remove(id);
+        self.render.cache.remove(id);
         let inst = self.remove(id, true);
         if let Some(inst) = &inst {
             for c in &inst.children {
@@ -217,16 +194,3 @@ impl<'a> DrawState<'a> {
         inst
     }
 }
-
-impl Deref for DrawState<'_> {
-    type Target = Ui;
-
-    fn deref(&self) -> &Self::Target {
-        self.ui
-    }
-}
-impl DerefMut for DrawState<'_> {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        self.ui
-    }
-}

core/src/ui/mod.rs

@@ -1,211 +1,49 @@
-use crate::{
-    EventsLike, IdLike, Mask, PixelRegion, PrimitiveLayers, TextData, TextureHandle, Textures,
-    Widget, WidgetHandle, WidgetId, Widgets,
-    ui::draw_state::DrawState,
-    util::{HashMap, TrackedArena, Vec2},
-};
-use image::DynamicImage;
-use std::{
-    ops::{Index, IndexMut},
-    sync::mpsc::{Receiver, channel},
-};
+use crate::{Mask, TextData, Textures, WeakWidget, WidgetId, Widgets, util::TrackedArena};
 
 mod active;
 mod cache;
-mod draw_state;
+// mod draw_state;
 mod painter;
+mod render_state;
 mod size;
 mod state;
 
 pub use active::*;
-use cache::*;
 pub use painter::Painter;
+pub use render_state::*;
 pub use size::*;
 
-pub struct Ui {
-    // TODO: edit visibilities
+#[derive(Default)]
+pub struct UiData {
     pub widgets: Widgets,
-
-    // retained painter state
-    pub active: HashMap<WidgetId, ActiveData>,
-    pub layers: PrimitiveLayers,
     pub textures: Textures,
     pub text: TextData,
-    output_size: Vec2,
     pub masks: TrackedArena<Mask, u32>,
-    pub cache: Cache,
-
-    pub root: Option<WidgetHandle>,
-    old_root: Option<WidgetId>,
-    recv: Receiver<WidgetId>,
-    resized: bool,
 }
 
-pub trait HasUi: Sized {
-    fn ui(&self) -> &Ui;
-    fn ui_mut(&mut self) -> &mut Ui;
-}
+pub trait UiRsc {
+    fn ui(&self) -> &UiData;
+    fn ui_mut(&mut self) -> &mut UiData;
 
-impl HasUi for Ui {
-    fn ui(&self) -> &Ui {
-        self
-    }
+    #[allow(unused_variables)]
+    fn on_add(&mut self, id: WeakWidget) {}
+    #[allow(unused_variables)]
+    fn on_remove(&mut self, id: WidgetId) {}
+    #[allow(unused_variables)]
+    fn on_draw(&mut self, active: &ActiveData) {}
+    #[allow(unused_variables)]
+    fn on_undraw(&mut self, active: &ActiveData) {}
 
-    fn ui_mut(&mut self) -> &mut Ui {
-        self
-    }
-}
-
-impl Ui {
-    /// useful for debugging
-    pub fn set_label(&mut self, id: impl IdLike, label: String) {
-        self.widgets.data_mut(id.id()).unwrap().label = label;
-    }
-
-    pub fn label(&self, id: impl IdLike) -> &String {
-        &self.widgets.data(id.id()).unwrap().label
-    }
-
-    pub fn new() -> Self {
-        Self::default()
-    }
-
-    pub fn get<I: IdLike>(&self, id: &I) -> Option<&I::Widget>
-    where
-        I::Widget: Sized + Widget,
-    {
-        self.widgets.get(id)
-    }
-
-    pub fn get_mut<I: IdLike>(&mut self, id: &I) -> Option<&mut I::Widget>
-    where
-        I::Widget: Sized + Widget,
-    {
-        self.widgets.get_mut(id)
-    }
-
-    pub fn add_texture(&mut self, image: DynamicImage) -> TextureHandle {
-        self.textures.add(image)
-    }
-
-    pub fn resize(&mut self, size: impl Into<Vec2>) {
-        self.output_size = size.into();
-        self.resized = true;
-    }
-
-    pub fn update(&mut self, events: &mut dyn EventsLike) {
-        if !self.widgets.waiting.is_empty() {
-            let len = self.widgets.waiting.len();
-            let all: Vec<_> = self
-                .widgets
-                .waiting
-                .iter()
-                .map(|&w| format!("'{}' ({w:?})", self.label(w)))
-                .collect();
-            panic!(
-                "{len} widget(s) were never upgraded\n\
-                this is likely a memory leak; consider upgrading to strong if you plan on using it later\n\
-                weak widgets: {all:#?}"
-            );
-        }
-        if self.root_changed() {
-            DrawState::new(self, events).redraw_all();
-            self.old_root = self.root.as_ref().map(|r| r.id());
-        } else if self.widgets.has_updates() {
-            DrawState::new(self, events).redraw_updates();
-        }
-        if self.resized {
-            self.resized = false;
-            DrawState::new(self, events).redraw_all();
-        }
-    }
-
-    /// free any resources that don't have references anymore
-    fn free(&mut self, events: &mut dyn EventsLike) {
-        for id in self.recv.try_iter() {
-            events.remove(id);
-            self.widgets.delete(id);
-        }
-        self.textures.free();
-    }
-
-    pub fn root_changed(&self) -> bool {
-        self.root.as_ref().map(|r| r.id()) != self.old_root
-    }
-
-    pub fn needs_redraw(&self) -> bool {
-        self.root_changed() || self.widgets.has_updates()
-    }
-
-    pub fn num_widgets(&self) -> usize {
-        self.widgets.len()
-    }
-
-    pub fn active_widgets(&self) -> usize {
-        self.active.len()
-    }
-
-    pub fn debug_layers(&self) {
-        for ((idx, depth), primitives) in self.layers.iter_depth() {
-            let indent = " ".repeat(depth * 2);
-            let len = primitives.instances().len();
-            print!("{indent}{idx}: {len} primitives");
-            if len >= 1 {
-                print!(" ({})", primitives.instances()[0].binding);
-            }
-            println!();
-        }
-    }
-
-    pub fn window_region(&self, id: &impl IdLike) -> Option<PixelRegion> {
-        let region = self.active.get(&id.id())?.region;
-        Some(region.to_px(self.output_size))
-    }
-
-    pub fn debug(&self, label: &str) -> impl Iterator<Item = &ActiveData> {
-        self.active.iter().filter_map(move |(&id, inst)| {
-            let l = self.widgets.label(id);
-            if l == label { Some(inst) } else { None }
-        })
-    }
-}
-
-impl<I: IdLike> Index<I> for Ui
-where
-    I::Widget: Sized + Widget,
-{
-    type Output = I::Widget;
-
-    fn index(&self, id: I) -> &Self::Output {
-        self.get(&id).unwrap()
-    }
-}
-
-impl<I: IdLike> IndexMut<I> for Ui
-where
-    I::Widget: Sized + Widget,
-{
-    fn index_mut(&mut self, id: I) -> &mut Self::Output {
-        self.get_mut(&id).unwrap()
-    }
-}
-
-impl Default for Ui {
-    fn default() -> Self {
-        let (send, recv) = channel();
-        Self {
-            widgets: Widgets::new(send),
-            active: Default::default(),
-            layers: Default::default(),
-            masks: Default::default(),
-            text: Default::default(),
-            textures: Default::default(),
-            cache: Default::default(),
-            output_size: Vec2::ZERO,
-            root: None,
-            old_root: None,
-            recv,
-            resized: false,
-        }
+    fn widgets(&self) -> &Widgets {
+        &self.ui().widgets
+    }
+    fn widgets_mut(&mut self) -> &mut Widgets {
+        &mut self.ui_mut().widgets
+    }
+    fn free(&mut self) {
+        while let Some(id) = self.widgets_mut().free_next() {
+            self.on_remove(id);
+        }
+        self.ui_mut().textures.free();
     }
 }

core/src/ui/painter.rs

@@ -1,14 +1,14 @@
 use crate::{
-    Axis, Len, RenderedText, Size, SizeCtx, TextAttrs, TextBuffer, TextData, TextureHandle,
-    UiRegion, Widget, WidgetHandle, WidgetId,
+    Axis, Len, RenderedText, Size, SizeCtx, StrongWidget, TextAttrs, TextBuffer, TextData,
+    TextureHandle, UiRegion, UiRenderState, UiRsc, Widget, WidgetId,
     render::{Mask, MaskIdx, Primitive, PrimitiveHandle, PrimitiveInst},
-    ui::draw_state::DrawState,
     util::Vec2,
 };
 
 /// makes your surfaces look pretty
-pub struct Painter<'a, 'b> {
-    pub(super) state: &'a mut DrawState<'b>,
+pub struct Painter<'a> {
+    pub(super) state: &'a mut UiRenderState,
+    pub(super) rsc: &'a mut dyn UiRsc,
 
     pub(super) region: UiRegion,
     pub(super) mask: MaskIdx,
@@ -19,7 +19,7 @@ pub struct Painter<'a, 'b> {
     pub(super) id: WidgetId,
 }
 
-impl<'a, 'c> Painter<'a, 'c> {
+impl<'a> Painter<'a> {
     fn primitive_at<P: Primitive>(&mut self, primitive: P, region: UiRegion) {
         let h = self.state.layers.write(
             self.layer,
@@ -32,7 +32,7 @@ impl<'a, 'c> Painter<'a, 'c> {
         );
         if self.mask != MaskIdx::NONE {
             // TODO: I have no clue if this works at all :joy:
-            self.state.masks.push_ref(self.mask);
+            self.rsc.ui_mut().masks.push_ref(self.mask);
         }
         self.primitives.push(h);
     }
@@ -48,24 +48,31 @@ impl<'a, 'c> Painter<'a, 'c> {
 
     pub fn set_mask(&mut self, region: UiRegion) {
         assert!(self.mask == MaskIdx::NONE);
-        self.mask = self.state.masks.push(Mask { region });
+        self.mask = self.rsc.ui_mut().masks.push(Mask { region });
     }
 
     /// Draws a widget within this widget's region.
-    pub fn widget<W: ?Sized>(&mut self, id: &WidgetHandle<W>) {
+    pub fn widget<W: ?Sized>(&mut self, id: &StrongWidget<W>) {
         self.widget_at(id, self.region);
     }
 
     /// Draws a widget somewhere within this one.
     /// Useful for drawing child widgets in select areas.
-    pub fn widget_within<W: ?Sized>(&mut self, id: &WidgetHandle<W>, region: UiRegion) {
+    pub fn widget_within<W: ?Sized>(&mut self, id: &StrongWidget<W>, region: UiRegion) {
         self.widget_at(id, region.within(&self.region));
     }
 
-    fn widget_at<W: ?Sized>(&mut self, id: &WidgetHandle<W>, region: UiRegion) {
+    fn widget_at<W: ?Sized>(&mut self, id: &StrongWidget<W>, region: UiRegion) {
         self.children.push(id.id());
-        self.state
-            .draw_inner(self.layer, id.id(), region, Some(self.id), self.mask, None);
+        self.state.draw_inner(
+            self.layer,
+            id.id(),
+            region,
+            Some(self.id),
+            self.mask,
+            None,
+            self.rsc,
+        );
     }
 
     pub fn texture_within(&mut self, handle: &TextureHandle, region: UiRegion) {
@@ -85,21 +92,19 @@ impl<'a, 'c> Painter<'a, 'c> {
 
     /// returns (handle, offset from top left)
     pub fn render_text(&mut self, buffer: &mut TextBuffer, attrs: &TextAttrs) -> RenderedText {
-        self.state
-            .ui
-            .text
-            .draw(buffer, attrs, &mut self.state.ui.textures)
+        let ui = self.rsc.ui_mut();
+        ui.text.draw(buffer, attrs, &mut ui.textures)
     }
 
     pub fn region(&self) -> UiRegion {
         self.region
     }
 
-    pub fn size<W: ?Sized + Widget>(&mut self, id: &WidgetHandle<W>) -> Size {
+    pub fn size<W: ?Sized + Widget>(&mut self, id: &StrongWidget<W>) -> Size {
         self.size_ctx().size(id)
     }
 
-    pub fn len_axis<W: ?Sized + Widget>(&mut self, id: &WidgetHandle<W>, axis: Axis) -> Len {
+    pub fn len_axis<W: ?Sized + Widget>(&mut self, id: &StrongWidget<W>, axis: Axis) -> Len {
         match axis {
             Axis::X => self.size_ctx().width(id),
             Axis::Y => self.size_ctx().height(id),
@@ -115,7 +120,7 @@ impl<'a, 'c> Painter<'a, 'c> {
     }
 
     pub fn text_data(&mut self) -> &mut TextData {
-        &mut self.state.text
+        &mut self.rsc.ui_mut().text
     }
 
     pub fn child_layer(&mut self) {
@@ -127,7 +132,7 @@ impl<'a, 'c> Painter<'a, 'c> {
     }
 
     pub fn label(&self) -> &str {
-        &self.state.widgets.data(self.id).unwrap().label
+        &self.rsc.widgets().data(self.id).unwrap().label
     }
 
     pub fn id(&self) -> &WidgetId {
@@ -135,6 +140,6 @@ impl<'a, 'c> Painter<'a, 'c> {
     }
 
     pub fn size_ctx(&mut self) -> SizeCtx<'_> {
-        self.state.size_ctx(self.id, self.region.size())
+        self.state.size_ctx(self.id, self.region.size(), self.rsc)
     }
 }

core/src/ui/render_state.rs

@@ -0,0 +1,319 @@
+use crate::{
+    ActiveData, Axis, IdLike, MaskIdx, Painter, PixelRegion, PrimitiveLayers, SizeCtx,
+    StrongWidget, UiRegion, UiRsc, UiVec2, WidgetId, Widgets,
+    ui::cache::Cache,
+    util::{HashMap, HashSet, Vec2, forget_ref},
+};
+
+pub struct UiRenderState {
+    pub active: HashMap<WidgetId, ActiveData>,
+    pub layers: PrimitiveLayers,
+    pub(super) output_size: Vec2,
+    pub cache: Cache,
+
+    old_root: Option<WidgetId>,
+    resized: bool,
+    draw_started: HashSet<WidgetId>,
+}
+
+impl UiRenderState {
+    pub fn new() -> Self {
+        Self {
+            active: Default::default(),
+            layers: Default::default(),
+            cache: Default::default(),
+            output_size: Vec2::ZERO,
+            old_root: None,
+            resized: false,
+            draw_started: Default::default(),
+        }
+    }
+
+    pub fn resize(&mut self, size: impl Into<Vec2>) {
+        self.output_size = size.into();
+        self.resized = true;
+    }
+
+    pub fn update<'a>(&mut self, root: impl Into<Option<&'a StrongWidget>>, rsc: &mut dyn UiRsc) {
+        // safety mechanism for memory leaks; might wanna return a result instead so user can
+        // decide whether to panic or not
+        if !rsc.widgets().waiting.is_empty() {
+            let widgets = rsc.widgets();
+            let len = widgets.waiting.len();
+            let all: Vec<_> = widgets
+                .waiting
+                .iter()
+                .map(|&w| format!("'{}' ({w:?})", widgets.label(w)))
+                .collect();
+            panic!(
+                "{len} widget(s) were never upgraded\n\
+                this is likely a memory leak; consider upgrading to strong if you plan on using it later\n\
+                weak widgets: {all:#?}"
+            );
+        }
+        let root = root.into();
+        if self.root_changed(root) || self.resized {
+            self.redraw_all(root, rsc);
+            self.old_root = root.map(|r| r.id());
+            self.resized = false;
+        } else if rsc.widgets().has_updates() {
+            self.redraw_updates(rsc);
+        }
+    }
+
+    fn redraw_all(&mut self, root: Option<&StrongWidget>, rsc: &mut dyn UiRsc) {
+        self.clear(rsc);
+        // free all resources & cache
+        if let Some(id) = root {
+            self.draw_inner(0, id.id(), UiRegion::FULL, None, MaskIdx::NONE, None, rsc);
+        }
+    }
+
+    // TODO: should prolly make a DrawInfo struct or smth for everything other than rsc
+    #[allow(clippy::too_many_arguments)]
+    pub(super) fn draw_inner(
+        &mut self,
+        layer: usize,
+        id: WidgetId,
+        region: UiRegion,
+        parent: Option<WidgetId>,
+        mask: MaskIdx,
+        old_children: Option<Vec<WidgetId>>,
+        rsc: &mut dyn UiRsc,
+    ) {
+        let mut old_children = old_children.unwrap_or_default();
+        if let Some(active) = self.active.get_mut(&id)
+            && !rsc.widgets().needs_redraw.contains(&id)
+        {
+            // check to see if we can skip drawing first
+            if active.region == region {
+                return;
+            } else if active.region.size() == region.size() {
+                // TODO: epsilon?
+                let from = active.region;
+                self.mov(id, from, region);
+                return;
+            }
+            // if not, then maintain resize and track old children to remove unneeded
+            let active = self.remove(id, false, rsc).unwrap();
+            old_children = active.children;
+        }
+
+        // draw widget
+        self.draw_started.insert(id);
+
+        let mut painter = Painter {
+            state: self,
+            region,
+            mask,
+            layer,
+            id,
+            textures: Vec::new(),
+            primitives: Vec::new(),
+            children: Vec::new(),
+            rsc,
+        };
+
+        let mut widget = painter.rsc.widgets().get_dyn_dynamic(id);
+        widget.draw(&mut painter);
+        drop(widget);
+
+        let Painter {
+            state: _,
+            rsc: _,
+            region,
+            mask,
+            textures,
+            primitives,
+            children,
+            layer,
+            id,
+        } = painter;
+
+        // add to active
+        let active = ActiveData {
+            id,
+            region,
+            parent,
+            textures,
+            primitives,
+            children,
+            mask,
+            layer,
+        };
+
+        // remove old children that weren't kept
+        for c in &old_children {
+            if !active.children.contains(c) {
+                self.remove_rec(*c, rsc);
+            }
+        }
+
+        rsc.on_draw(&active);
+        self.active.insert(id, active);
+    }
+
+    fn mov(&mut self, id: WidgetId, from: UiRegion, to: UiRegion) {
+        let active = self.active.get_mut(&id).unwrap();
+        for h in &active.primitives {
+            let region = self.layers[h.layer].region_mut(h);
+            *region = region.outside(&from).within(&to);
+        }
+        active.region = active.region.outside(&from).within(&to);
+        // SAFETY: children cannot be recursive
+        let children = unsafe { forget_ref(&active.children) };
+        for child in children {
+            self.mov(*child, from, to);
+        }
+    }
+
+    /// NOTE: instance textures are cleared and self.textures freed
+    fn remove(&mut self, id: WidgetId, undraw: bool, rsc: &mut dyn UiRsc) -> Option<ActiveData> {
+        let mut active = self.active.remove(&id);
+        if let Some(active) = &mut active {
+            for h in &active.primitives {
+                let mask = self.layers.free(h);
+                if mask != MaskIdx::NONE {
+                    rsc.ui_mut().masks.remove(mask);
+                }
+            }
+            active.textures.clear();
+            rsc.ui_mut().textures.free();
+            if undraw {
+                rsc.on_undraw(active);
+            }
+        }
+        active
+    }
+
+    fn remove_rec(&mut self, id: WidgetId, rsc: &mut dyn UiRsc) -> Option<ActiveData> {
+        self.cache.remove(id);
+        let inst = self.remove(id, true, rsc);
+        if let Some(inst) = &inst {
+            for c in &inst.children {
+                self.remove_rec(*c, rsc);
+            }
+        }
+        inst
+    }
+
+    fn clear(&mut self, rsc: &mut dyn UiRsc) {
+        for (_, active) in self.active.drain() {
+            rsc.on_undraw(&active);
+        }
+        self.cache.clear();
+        self.layers.clear();
+        rsc.widgets_mut().needs_redraw.clear();
+        rsc.free();
+    }
+
+    pub fn redraw_updates(&mut self, rsc: &mut dyn UiRsc) {
+        while let Some(&id) = rsc.widgets().needs_redraw.iter().next() {
+            self.redraw(id, rsc);
+        }
+        rsc.free();
+    }
+
+    pub fn root_changed<'a>(&self, root: impl Into<Option<&'a StrongWidget>>) -> bool {
+        root.into().map(|r| r.id()) != self.old_root
+    }
+
+    pub fn needs_redraw<'a>(
+        &self,
+        root: impl Into<Option<&'a StrongWidget>>,
+        widgets: &Widgets,
+    ) -> bool {
+        self.root_changed(root) || widgets.has_updates()
+    }
+
+    pub fn active_widgets(&self) -> usize {
+        self.active.len()
+    }
+
+    pub fn debug(&self, widgets: &Widgets, label: &str) -> impl Iterator<Item = &ActiveData> {
+        self.active.iter().filter_map(move |(&id, inst)| {
+            let l = widgets.label(id);
+            if l == label { Some(inst) } else { None }
+        })
+    }
+
+    pub fn debug_layers(&self) {
+        for ((idx, depth), primitives) in self.layers.iter_depth() {
+            let indent = " ".repeat(depth * 2);
+            let len = primitives.instances().len();
+            print!("{indent}{idx}: {len} primitives");
+            if len >= 1 {
+                print!(" ({})", primitives.instances()[0].binding);
+            }
+            println!();
+        }
+    }
+
+    pub fn window_region(&self, id: &impl IdLike) -> Option<PixelRegion> {
+        let region = self.active.get(&id.id())?.region;
+        Some(region.to_px(self.output_size))
+    }
+
+    /// redraws a widget that's currently active (drawn)
+    pub fn redraw(&mut self, id: WidgetId, rsc: &mut dyn UiRsc) {
+        rsc.widgets_mut().needs_redraw.remove(&id);
+        self.draw_started.remove(&id);
+        // check if parent depends on the desired size of this, if so then redraw it first
+        for axis in [Axis::X, Axis::Y] {
+            if let Some(&(outer, old)) = self.cache.size.axis_dyn(axis).get(&id)
+                && let Some(current) = self.active.get(&id)
+                && let Some(pid) = current.parent
+            {
+                self.cache.size.axis_dyn(axis).remove(&id);
+                let new = self.size_ctx(id, outer, rsc).len_axis(id, axis);
+                self.cache.size.axis_dyn(axis).insert(id, (outer, new));
+                if new != old {
+                    self.redraw(pid, rsc);
+                }
+            }
+        }
+
+        if self.draw_started.contains(&id) {
+            return;
+        }
+
+        let Some(active) = self.remove(id, false, rsc) else {
+            return;
+        };
+
+        self.draw_inner(
+            active.layer,
+            id,
+            active.region,
+            active.parent,
+            active.mask,
+            Some(active.children),
+            rsc,
+        );
+    }
+
+    pub(super) fn size_ctx<'b>(
+        &'b mut self,
+        source: WidgetId,
+        outer: UiVec2,
+        rsc: &'b mut dyn UiRsc,
+    ) -> SizeCtx<'b> {
+        let ui = rsc.ui_mut();
+        SizeCtx {
+            source,
+            cache: &mut self.cache,
+            text: &mut ui.text,
+            textures: &mut ui.textures,
+            widgets: &ui.widgets,
+            outer,
+            output_size: self.output_size,
+            id: source,
+        }
+    }
+}
+
+impl Default for UiRenderState {
+    fn default() -> Self {
+        Self::new()
+    }
+}

core/src/widget/handle.rs

@@ -1,7 +1,7 @@
 use std::{marker::Unsize, ops::CoerceUnsized, sync::mpsc::Sender};
 
 use crate::{
-    HasUi, Widget,
+    UiRsc, Widget,
     util::{RefCounter, SlotId},
 };
 
@@ -12,7 +12,7 @@ pub type WidgetId = SlotId;
 /// a signal is sent to the owning UI to clean up the resources.
 ///
 /// TODO: ergonomic clones when they get put in rust-analyzer & don't cause ICEs?
-pub struct WidgetHandle<W: ?Sized = dyn Widget> {
+pub struct StrongWidget<W: ?Sized = dyn Widget> {
     pub(super) id: WidgetId,
     counter: RefCounter,
     send: Sender<WidgetId>,
@@ -21,24 +21,19 @@ pub struct WidgetHandle<W: ?Sized = dyn Widget> {
 
 /// A weak handle to a widget.
 /// Will not keep it alive, but can still be used for indexing like WidgetHandle.
-pub struct WidgetRef<W: ?Sized = dyn Widget> {
+pub struct WeakWidget<W: ?Sized = dyn Widget> {
     pub(super) id: WidgetId,
     #[allow(unused)]
     ty: *const W,
 }
 
-pub struct WidgetHandles<W: ?Sized = dyn Widget> {
-    pub h: WidgetHandle<W>,
-    pub r: WidgetRef<W>,
-}
-
-impl<W: Widget + ?Sized + Unsize<dyn Widget>> WidgetHandle<W> {
-    pub fn any(self) -> WidgetHandle<dyn Widget> {
+impl<W: Widget + ?Sized + Unsize<dyn Widget>> StrongWidget<W> {
+    pub fn any(self) -> StrongWidget<dyn Widget> {
         self
     }
 }
 
-impl<W: ?Sized> WidgetHandle<W> {
+impl<W: ?Sized> StrongWidget<W> {
     pub(crate) fn new(id: WidgetId, send: Sender<WidgetId>) -> Self {
         Self {
             id,
@@ -56,18 +51,13 @@ impl<W: ?Sized> WidgetHandle<W> {
         self.counter.refs()
     }
 
-    pub fn weak(&self) -> WidgetRef<W> {
+    pub fn weak(&self) -> WeakWidget<W> {
         let Self { ty, id, .. } = *self;
-        WidgetRef { ty, id }
-    }
-
-    pub fn handles(self) -> WidgetHandles<W> {
-        let r = self.weak();
-        WidgetHandles { h: self, r }
+        WeakWidget { ty, id }
     }
 }
 
-impl<W: ?Sized> WidgetRef<W> {
+impl<W: ?Sized> WeakWidget<W> {
     pub(crate) fn new(id: WidgetId) -> Self {
         Self { id, ty: null_ptr() }
     }
@@ -77,12 +67,12 @@ impl<W: ?Sized> WidgetRef<W> {
     }
 
     #[track_caller]
-    pub fn upgrade(self, ui: &mut impl HasUi) -> WidgetHandle<W> {
-        ui.ui_mut().widgets.upgrade(self)
+    pub fn upgrade(self, ui: &mut impl UiRsc) -> StrongWidget<W> {
+        ui.widgets_mut().upgrade(self)
     }
 }
 
-impl<W: ?Sized> Drop for WidgetHandle<W> {
+impl<W: ?Sized> Drop for StrongWidget<W> {
     fn drop(&mut self) {
         if self.counter.drop() {
             let _ = self.send.send(self.id);
@@ -90,29 +80,29 @@ impl<W: ?Sized> Drop for WidgetHandle<W> {
     }
 }
 
-pub trait WidgetIdFn<Rsc, W: ?Sized = dyn Widget>: FnOnce(&mut Rsc) -> WidgetRef<W> {}
-impl<Rsc, W: ?Sized, F: FnOnce(&mut Rsc) -> WidgetRef<W>> WidgetIdFn<Rsc, W> for F {}
+pub trait WidgetIdFn<Rsc, W: ?Sized = dyn Widget>: FnOnce(&mut Rsc) -> WeakWidget<W> {}
+impl<Rsc, W: ?Sized, F: FnOnce(&mut Rsc) -> WeakWidget<W>> WidgetIdFn<Rsc, W> for F {}
 
 pub trait IdLike {
     type Widget: ?Sized;
     fn id(&self) -> WidgetId;
 }
 
-impl<W: ?Sized> IdLike for &WidgetHandle<W> {
+impl<W: ?Sized> IdLike for &StrongWidget<W> {
     type Widget = W;
     fn id(&self) -> WidgetId {
         self.id
     }
 }
 
-impl<W: ?Sized> IdLike for WidgetHandle<W> {
+impl<W: ?Sized> IdLike for StrongWidget<W> {
     type Widget = W;
     fn id(&self) -> WidgetId {
         self.id
     }
 }
 
-impl<W: ?Sized> IdLike for WidgetRef<W> {
+impl<W: ?Sized> IdLike for WeakWidget<W> {
     type Widget = W;
     fn id(&self) -> WidgetId {
         self.id
@@ -126,38 +116,38 @@ impl IdLike for WidgetId {
     }
 }
 
-impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<WidgetHandle<U>> for WidgetHandle<T> {}
-impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<WidgetRef<U>> for WidgetRef<T> {}
+impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<StrongWidget<U>> for StrongWidget<T> {}
+impl<T: ?Sized + Unsize<U>, U: ?Sized> CoerceUnsized<WeakWidget<U>> for WeakWidget<T> {}
 
-impl<W: ?Sized> Clone for WidgetRef<W> {
+impl<W: ?Sized> Clone for WeakWidget<W> {
     fn clone(&self) -> Self {
         *self
     }
 }
-impl<W: ?Sized> Copy for WidgetRef<W> {}
-impl<W: ?Sized> PartialEq for WidgetRef<W> {
+impl<W: ?Sized> Copy for WeakWidget<W> {}
+impl<W: ?Sized> PartialEq for WeakWidget<W> {
     fn eq(&self, other: &Self) -> bool {
         self.id == other.id
     }
 }
 
-impl<W> PartialEq for WidgetHandle<W> {
+impl<W> PartialEq for StrongWidget<W> {
     fn eq(&self, other: &Self) -> bool {
         self.id == other.id
     }
 }
 
-impl<W> std::fmt::Debug for WidgetHandle<W> {
+impl<W> std::fmt::Debug for StrongWidget<W> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         self.id.fmt(f)
     }
 }
 
-impl<'a, W: Widget + 'a, State: HasUi> FnOnce<(&'a mut State,)> for WidgetRef<W> {
+impl<'a, W: Widget + 'a, State: UiRsc> FnOnce<(&'a mut State,)> for WeakWidget<W> {
     type Output = &'a mut W;
 
     extern "rust-call" fn call_once(self, args: (&'a mut State,)) -> Self::Output {
-        &mut args.0.ui_mut()[self]
+        &mut args.0.widgets_mut()[self]
     }
 }
 
@@ -170,5 +160,5 @@ fn null_ptr<W: ?Sized>() -> *const W {
     }
 }
 
-unsafe impl<W: ?Sized> Send for WidgetRef<W> {}
-unsafe impl<W: ?Sized> Sync for WidgetRef<W> {}
+unsafe impl<W: ?Sized> Send for WeakWidget<W> {}
+unsafe impl<W: ?Sized> Sync for WeakWidget<W> {}

core/src/widget/like.rs

@@ -1,20 +1,20 @@
-use crate::HasUi;
+use crate::UiRsc;
 
 use super::*;
 use std::marker::Unsize;
 
-pub trait WidgetLike<Rsc: HasUi, Tag>: Sized {
+pub trait WidgetLike<Rsc: UiRsc, Tag>: Sized {
     type Widget: Widget + ?Sized + Unsize<dyn Widget>;
 
-    fn add(self, rsc: &mut Rsc) -> WidgetRef<Self::Widget>;
+    fn add(self, rsc: &mut Rsc) -> WeakWidget<Self::Widget>;
 
-    fn add_strong(self, rsc: &mut Rsc) -> WidgetHandle<Self::Widget> {
-        self.add(rsc).upgrade(rsc.ui_mut())
+    fn add_strong(self, rsc: &mut Rsc) -> StrongWidget<Self::Widget> {
+        self.add(rsc).upgrade(rsc)
     }
 
     fn with_id<W2>(
         self,
-        f: impl FnOnce(&mut Rsc, WidgetRef<Self::Widget>) -> WidgetRef<W2>,
+        f: impl FnOnce(&mut Rsc, WeakWidget<Self::Widget>) -> WeakWidget<W2>,
     ) -> impl WidgetIdFn<Rsc, W2> {
         move |state| {
             let id = self.add(state);
@@ -22,15 +22,14 @@ pub trait WidgetLike<Rsc: HasUi, Tag>: Sized {
         }
     }
 
-    fn set_root(self, state: &mut Rsc) {
-        let id = self.add(state);
-        let ui = state.ui_mut();
-        ui.root = Some(id.upgrade(ui));
+    fn set_root(self, rsc: &mut Rsc, root: &mut impl HasRoot) {
+        let id = self.add_strong(rsc);
+        root.set_root(id);
+    }
 }
 
-    fn handles(self, state: &mut Rsc) -> WidgetHandles<Self::Widget> {
-        self.add(state).upgrade(state.ui_mut()).handles()
-    }
+pub trait HasRoot {
+    fn set_root(&mut self, root: StrongWidget);
 }
 
 pub trait WidgetArrLike<Rsc, const LEN: usize, Tag> {
@@ -50,12 +49,12 @@ macro_rules! impl_widget_arr {
         impl_widget_arr!($n;$($W)*;$(${concat($W,Tag)})*);
     };
     ($n:expr;$($W:ident)*;$($Tag:ident)*) => {
-        impl<Rsc: HasUi, $($W: WidgetLike<Rsc, $Tag>,$Tag,)*> WidgetArrLike<Rsc, $n, ($($Tag,)*)> for ($($W,)*) {
+        impl<Rsc: UiRsc, $($W: WidgetLike<Rsc, $Tag>,$Tag,)*> WidgetArrLike<Rsc, $n, ($($Tag,)*)> for ($($W,)*) {
             fn add(self, rsc: &mut Rsc) -> WidgetArr<$n> {
                 #[allow(non_snake_case)]
                 let ($($W,)*) = self;
                 WidgetArr::new(
-                    [$($W.add(rsc).upgrade(rsc.ui_mut()),)*],
+                    [$($W.add(rsc).upgrade(rsc),)*],
                 )
             }
         }

core/src/widget/mod.rs

@@ -61,27 +61,27 @@ pub trait WidgetFn<State, W: Widget + ?Sized>: FnOnce(&mut State) -> W {}
 impl<State, W: Widget + ?Sized, F: FnOnce(&mut State) -> W> WidgetFn<State, W> for F {}
 
 pub struct WidgetArr<const LEN: usize> {
-    pub arr: [WidgetHandle; LEN],
+    pub arr: [StrongWidget; LEN],
 }
 
 impl<const LEN: usize> WidgetArr<LEN> {
-    pub fn new(arr: [WidgetHandle; LEN]) -> Self {
+    pub fn new(arr: [StrongWidget; LEN]) -> Self {
         Self { arr }
     }
 }
 
 pub trait WidgetOption<State> {
-    fn get(self, state: &mut State) -> Option<WidgetHandle>;
+    fn get(self, state: &mut State) -> Option<StrongWidget>;
 }
 
 impl<State> WidgetOption<State> for () {
-    fn get(self, _: &mut State) -> Option<WidgetHandle> {
+    fn get(self, _: &mut State) -> Option<StrongWidget> {
         None
     }
 }
 
-impl<State, F: FnOnce(&mut State) -> Option<WidgetHandle>> WidgetOption<State> for F {
-    fn get(self, state: &mut State) -> Option<WidgetHandle> {
+impl<State, F: FnOnce(&mut State) -> Option<StrongWidget>> WidgetOption<State> for F {
+    fn get(self, state: &mut State) -> Option<StrongWidget> {
         self(state)
     }
 }

core/src/widget/tag.rs

@@ -1,19 +1,21 @@
 use super::*;
-use crate::HasUi;
+use crate::UiRsc;
 use std::marker::Unsize;
 
 pub struct WidgetTag;
-impl<Rsc: HasUi, W: Widget> WidgetLike<Rsc, WidgetTag> for W {
+impl<Rsc: UiRsc, W: Widget> WidgetLike<Rsc, WidgetTag> for W {
     type Widget = W;
-    fn add(self, rsc: &mut Rsc) -> WidgetRef<W> {
-        rsc.ui_mut().widgets.add_weak(self)
+    fn add(self, rsc: &mut Rsc) -> WeakWidget<W> {
+        let w = rsc.ui_mut().widgets.add_weak(self);
+        rsc.on_add(w);
+        w
     }
 }
 
 pub struct FnTag;
-impl<Rsc: HasUi, W: Widget, F: FnOnce(&mut Rsc) -> W> WidgetLike<Rsc, FnTag> for F {
+impl<Rsc: UiRsc, W: Widget, F: FnOnce(&mut Rsc) -> W> WidgetLike<Rsc, FnTag> for F {
     type Widget = W;
-    fn add(self, rsc: &mut Rsc) -> WidgetRef<W> {
+    fn add(self, rsc: &mut Rsc) -> WeakWidget<W> {
         self(rsc).add(rsc)
     }
 }
@@ -23,36 +25,38 @@ pub trait WidgetFnTrait<Rsc> {
     fn run(self, rsc: &mut Rsc) -> Self::Widget;
 }
 pub struct FnTraitTag;
-impl<Rsc: HasUi, T: WidgetFnTrait<Rsc>> WidgetLike<Rsc, FnTraitTag> for T {
+impl<Rsc: UiRsc, T: WidgetFnTrait<Rsc>> WidgetLike<Rsc, FnTraitTag> for T {
     type Widget = T::Widget;
     #[track_caller]
-    fn add(self, rsc: &mut Rsc) -> WidgetRef<T::Widget> {
+    fn add(self, rsc: &mut Rsc) -> WeakWidget<T::Widget> {
         self.run(rsc).add(rsc)
     }
 }
 
 pub struct RefTag;
-impl<Rsc: HasUi, W: ?Sized + Widget + Unsize<dyn Widget>> WidgetLike<Rsc, RefTag> for WidgetRef<W> {
+impl<Rsc: UiRsc, W: ?Sized + Widget + Unsize<dyn Widget>> WidgetLike<Rsc, RefTag>
+    for WeakWidget<W>
+{
     type Widget = W;
-    fn add(self, _: &mut Rsc) -> WidgetRef<W> {
+    fn add(self, _: &mut Rsc) -> WeakWidget<W> {
         self
     }
 }
 
 pub struct RefFnTag;
-impl<Rsc: HasUi, W: ?Sized + Widget + Unsize<dyn Widget>, F: FnOnce(&mut Rsc) -> WidgetRef<W>>
+impl<Rsc: UiRsc, W: ?Sized + Widget + Unsize<dyn Widget>, F: FnOnce(&mut Rsc) -> WeakWidget<W>>
     WidgetLike<Rsc, RefFnTag> for F
 {
     type Widget = W;
-    fn add(self, rsc: &mut Rsc) -> WidgetRef<W> {
+    fn add(self, rsc: &mut Rsc) -> WeakWidget<W> {
         self(rsc)
     }
 }
 
 pub struct ViewTag;
-impl<Rsc: HasUi, V: WidgetView> WidgetLike<Rsc, ViewTag> for V {
+impl<Rsc: UiRsc, V: WidgetView> WidgetLike<Rsc, ViewTag> for V {
     type Widget = V::Widget;
-    fn add(self, _: &mut Rsc) -> WidgetRef<Self::Widget> {
+    fn add(self, _: &mut Rsc) -> WeakWidget<Self::Widget> {
         self.root()
     }
 }

core/src/widget/view.rs

@@ -1,16 +1,16 @@
 use std::marker::Unsize;
 
-use crate::{Widget, WidgetRef};
+use crate::{Widget, WeakWidget};
 
 pub trait WidgetView {
     type Widget: Widget + ?Sized + Unsize<dyn Widget>;
-    fn root(&self) -> WidgetRef<Self::Widget>;
+    fn root(&self) -> WeakWidget<Self::Widget>;
 }
 
 pub trait HasWidget {
     type Widget: Widget + ?Sized + Unsize<dyn Widget>;
 }
 
-impl<W: Widget + Unsize<dyn Widget> + ?Sized> HasWidget for WidgetRef<W> {
+impl<W: Widget + Unsize<dyn Widget> + ?Sized> HasWidget for WeakWidget<W> {
     type Widget = W;
 }

core/src/widget/widgets.rs

@@ -1,7 +1,7 @@
-use std::sync::mpsc::Sender;
+use std::sync::mpsc::{Receiver, Sender, channel};
 
 use crate::{
-    IdLike, Widget, WidgetData, WidgetHandle, WidgetId, WidgetRef,
+    IdLike, StrongWidget, WeakWidget, Widget, WidgetData, WidgetId,
     util::{DynBorrower, HashSet, SlotVec, forget_mut, to_mut},
 };
 
@@ -9,16 +9,19 @@ pub struct Widgets {
     pub needs_redraw: HashSet<WidgetId>,
     vec: SlotVec<WidgetData>,
     send: Sender<WidgetId>,
+    recv: Receiver<WidgetId>,
     pub(crate) waiting: HashSet<WidgetId>,
 }
 
 impl Widgets {
-    pub fn new(send: Sender<WidgetId>) -> Self {
+    pub fn new() -> Self {
+        let (send, recv) = channel();
         Self {
             needs_redraw: Default::default(),
             vec: Default::default(),
             waiting: Default::default(),
             send,
+            recv,
         }
     }
 
@@ -61,25 +64,27 @@ impl Widgets {
         self.get_dyn_mut(id.id())?.as_any_mut().downcast_mut()
     }
 
-    pub fn add_strong<W: Widget>(&mut self, widget: W) -> WidgetHandle<W> {
+    pub fn add_strong<W: Widget>(&mut self, widget: W) -> StrongWidget<W> {
         let id = self.vec.add(WidgetData::new(widget));
-        WidgetHandle::new(id, self.send.clone())
+        StrongWidget::new(id, self.send.clone())
     }
 
-    pub fn add_weak<W: Widget>(&mut self, widget: W) -> WidgetRef<W> {
+    pub fn add_weak<W: Widget>(&mut self, widget: W) -> WeakWidget<W> {
         let id = self.vec.add(WidgetData::new(widget));
         self.waiting.insert(id);
-        WidgetRef::new(id)
+        WeakWidget::new(id)
     }
 
     #[track_caller]
-    pub fn upgrade<W: ?Sized>(&mut self, rf: WidgetRef<W>) -> WidgetHandle<W> {
+    pub fn upgrade<W: ?Sized>(&mut self, rf: WeakWidget<W>) -> StrongWidget<W> {
         if !self.waiting.remove(&rf.id()) {
             let label = self.label(rf);
             let id = rf.id();
-            panic!("widget '{label}' ({id:?}) was already added\ncannot add a widget twice; consider creating two")
+            panic!(
+                "widget '{label}' ({id:?}) was already added\ncannot add a widget twice; consider creating two"
+            )
         }
-        WidgetHandle::new(rf.id(), self.send.clone())
+        StrongWidget::new(rf.id(), self.send.clone())
     }
 
     pub fn data(&self, id: impl IdLike) -> Option<&WidgetData> {
@@ -90,14 +95,19 @@ impl Widgets {
         &self.data(id.id()).unwrap().label
     }
 
+    /// useful for debugging
+    pub fn set_label(&mut self, id: impl IdLike, label: String) {
+        self.data_mut(id.id()).unwrap().label = label;
+    }
+
     pub fn data_mut(&mut self, id: impl IdLike) -> Option<&mut WidgetData> {
         self.vec.get_mut(id.id())
     }
 
-    pub fn delete(&mut self, id: impl IdLike) {
-        self.vec.free(id.id());
-        // not sure if there's any point in this
-        // self.updates.remove(&id);
+    pub fn free_next(&mut self) -> Option<WidgetId> {
+        let next = self.recv.try_recv().ok()?;
+        self.vec.free(next);
+        Some(next)
     }
 
     #[allow(clippy::len_without_is_empty)]
@@ -106,4 +116,30 @@ impl Widgets {
     }
 }
 
+impl Default for Widgets {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
 pub type WidgetWrapper<'a> = DynBorrower<'a, dyn Widget>;
+
+impl<I: IdLike> std::ops::Index<I> for Widgets
+where
+    I::Widget: Sized + Widget,
+{
+    type Output = I::Widget;
+
+    fn index(&self, id: I) -> &Self::Output {
+        self.get(&id).unwrap()
+    }
+}
+
+impl<I: IdLike> std::ops::IndexMut<I> for Widgets
+where
+    I::Widget: Sized + Widget,
+{
+    fn index_mut(&mut self, id: I) -> &mut Self::Output {
+        self.get_mut(&id).unwrap()
+    }
+}

examples/minimal.rs

@@ -10,8 +10,12 @@ struct State {
 }
 
 impl DefaultAppState for State {
-    fn new(ui_state: DefaultUiState, rsc: &mut DefaultRsc<Self>, _: Proxy<Self::Event>) -> Self {
-        rect(Color::RED).set_root(rsc);
+    fn new(
+        mut ui_state: DefaultUiState,
+        rsc: &mut DefaultRsc<Self>,
+        _: Proxy<Self::Event>,
+    ) -> Self {
+        rect(Color::RED).set_root(rsc, &mut ui_state);
         Self { ui_state }
     }
 }

examples/tabs/main.rs

@@ -12,11 +12,15 @@ fn main() {
 #[derive(DefaultUiState)]
 pub struct Client {
     ui_state: DefaultUiState,
-    info: WidgetRef<Text>,
+    info: WeakWidget<Text>,
 }
 
 impl DefaultAppState for Client {
-    fn new(ui_state: DefaultUiState, rsc: &mut DefaultRsc<Self>, _: Proxy<Self::Event>) -> Self {
+    fn new(
+        mut ui_state: DefaultUiState,
+        rsc: &mut DefaultRsc<Self>,
+        _: Proxy<Self::Event>,
+    ) -> Self {
         let rrect = rect(Color::WHITE).radius(20);
         let pad_test = (
             rrect.color(Color::BLUE),
@@ -147,7 +151,7 @@ impl DefaultAppState for Client {
         let main = WidgetPtr::new().add(rsc);
 
         let vals = Rc::new(RefCell::new((0, Vec::new())));
-        let mut switch_button = |color, to: WidgetRef, label| {
+        let mut switch_button = |color, to: WeakWidget, label| {
             let to = to.upgrade(rsc);
             let vec = &mut vals.borrow_mut().1;
             let i = vec.len();
@@ -197,20 +201,25 @@ impl DefaultAppState for Client {
 
         ((tabs.height(40), main.pad(10)).span(Dir::DOWN), info_sect)
             .stack()
-            .set_root(rsc);
+            .set_root(rsc, &mut ui_state);
 
         Self { ui_state, info }
     }
 
-    fn window_event(&mut self, _: WindowEvent, rsc: &mut DefaultRsc<Self>) {
+    fn window_event(
+        &mut self,
+        _: WindowEvent,
+        rsc: &mut DefaultRsc<Self>,
+        render: &mut UiRenderState,
+    ) {
         let new = format!(
             "widgets: {}\nactive: {}\nviews: {}",
-            rsc.ui.num_widgets(),
-            rsc.ui.active_widgets(),
-            self.ui_state.renderer.ui.view_count()
+            rsc.widgets().len(),
+            render.active_widgets(),
+            self.ui_state.renderer.ui.view_count(),
         );
-        if new != *rsc.ui[self.info].content {
-            *rsc.ui[self.info].content = new;
+        if new != *rsc.widgets()[self.info].content {
+            *rsc.widgets_mut()[self.info].content = new;
         }
     }
 }

examples/task.rs

@@ -11,11 +11,15 @@ struct State {
 }
 
 impl DefaultAppState for State {
-    fn new(ui_state: DefaultUiState, rsc: &mut DefaultRsc<Self>, _: Proxy<Self::Event>) -> Self {
+    fn new(
+        mut ui_state: DefaultUiState,
+        rsc: &mut DefaultRsc<Self>,
+        _: Proxy<Self::Event>,
+    ) -> Self {
         let rect = rect(Color::RED).add(rsc);
         rect.task_on(CursorSense::click(), async move |mut ctx| {
             tokio::time::sleep(Duration::from_secs(1)).await;
-            ctx.task.update(move |_, rsc| {
+            ctx.update(move |_, rsc| {
                 let rect = rect(rsc);
                 if rect.color == Color::RED {
                     rect.color = Color::BLUE;
@@ -24,7 +28,7 @@ impl DefaultAppState for State {
                 }
             });
         })
-        .set_root(rsc);
+        .set_root(rsc, &mut ui_state);
         Self { ui_state }
     }
 }

examples/view.rs

@@ -14,7 +14,7 @@ type Rsc = DefaultRsc<State>;
 #[derive(Clone, Copy, WidgetView)]
 struct Test {
     #[root]
-    root: WidgetRef<Rect>,
+    root: WeakWidget<Rect>,
 }
 
 impl Test {
@@ -33,13 +33,17 @@ impl Test {
 }
 
 impl DefaultAppState for State {
-    fn new(ui_state: DefaultUiState, rsc: &mut DefaultRsc<Self>, _: Proxy<Self::Event>) -> Self {
+    fn new(
+        mut ui_state: DefaultUiState,
+        rsc: &mut DefaultRsc<Self>,
+        _: Proxy<Self::Event>,
+    ) -> Self {
         let test = Test::new(rsc);
 
         test.on(CursorSense::click(), move |_, rsc| {
             test.toggle(rsc);
         })
-        .set_root(rsc);
+        .set_root(rsc, &mut ui_state);
 
         Self { ui_state }
     }

src/default/attr.rs

@@ -8,16 +8,24 @@ impl<Rsc: HasEvents, W: Widget + 'static> WidgetAttr<Rsc, W> for Selector
 where
     Rsc::State: HasDefaultUiState,
 {
-    type Input = WidgetRef<TextEdit>;
+    type Input = WeakWidget<TextEdit>;
 
-    fn run(rsc: &mut Rsc, container: WidgetRef<W>, id: Self::Input) {
+    fn run(rsc: &mut Rsc, container: WeakWidget<W>, id: Self::Input) {
         rsc.register_event(container, CursorSense::click_or_drag(), move |ctx, rsc| {
-            let region = rsc.ui().window_region(&id).unwrap();
+            let region = ctx.data.render.window_region(&id).unwrap();
             let id_pos = region.top_left;
-            let container_pos = rsc.ui().window_region(&container).unwrap().top_left;
+            let container_pos = ctx.data.render.window_region(&container).unwrap().top_left;
             let pos = ctx.data.pos + container_pos - id_pos;
             let size = region.size();
-            select(rsc, ctx.state, id, pos, size, ctx.data.sense.is_dragging());
+            select(
+                rsc,
+                ctx.data.render,
+                ctx.state,
+                id,
+                pos,
+                size,
+                ctx.data.sense.is_dragging(),
+            );
         });
     }
 }
@@ -30,10 +38,11 @@ where
 {
     type Input = ();
 
-    fn run(rsc: &mut Rsc, id: WidgetRef<TextEdit>, _: Self::Input) {
+    fn run(rsc: &mut Rsc, id: WeakWidget<TextEdit>, _: Self::Input) {
         rsc.register_event(id, CursorSense::click_or_drag(), move |ctx, rsc| {
             select(
                 rsc,
+                ctx.data.render,
                 ctx.state,
                 id,
                 ctx.data.pos,
@@ -45,9 +54,10 @@ where
 }
 
 fn select(
-    rsc: &mut impl HasUi,
+    rsc: &mut impl UiRsc,
+    render: &UiRenderState,
     state: &mut impl HasDefaultUiState,
-    id: WidgetRef<TextEdit>,
+    id: WeakWidget<TextEdit>,
     pos: Vec2,
     size: Vec2,
     dragging: bool,
@@ -57,7 +67,7 @@ fn select(
     let recent = (now - state.last_click) < Duration::from_millis(300);
     state.last_click = now;
     id.edit(rsc).select(pos, size, dragging, recent);
-    if let Some(region) = rsc.ui().window_region(&id) {
+    if let Some(region) = render.window_region(&id) {
         state.window.set_ime_allowed(true);
         state.window.set_ime_cursor_area(
             LogicalPosition::<f32>::from(region.top_left.tuple()),

src/default/mod.rs

@@ -30,19 +30,27 @@ pub use task::*;
 pub type Proxy<Event> = EventLoopProxy<Event>;
 
 pub struct DefaultUiState {
+    pub root: Option<StrongWidget>,
     pub renderer: UiRenderer,
     pub input: Input,
-    pub focus: Option<WidgetRef<TextEdit>>,
+    pub focus: Option<WeakWidget<TextEdit>>,
     pub clipboard: Clipboard,
     pub window: Arc<Window>,
     pub ime: usize,
     pub last_click: Instant,
 }
 
+impl HasRoot for DefaultUiState {
+    fn set_root(&mut self, root: StrongWidget) {
+        self.root = Some(root);
+    }
+}
+
 impl DefaultUiState {
     pub fn new(window: impl Into<Arc<Window>>) -> Self {
         let window = window.into();
         Self {
+            root: None,
             renderer: UiRenderer::new(window.clone()),
             window,
             input: Input::default(),
@@ -64,18 +72,30 @@ pub trait DefaultAppState: HasDefaultUiState {
     fn new(ui_state: DefaultUiState, rsc: &mut DefaultRsc<Self>, proxy: Proxy<Self::Event>)
     -> Self;
     #[allow(unused_variables)]
-    fn event(&mut self, event: Self::Event, rsc: &mut DefaultRsc<Self>) {}
+    fn event(
+        &mut self,
+        event: Self::Event,
+        rsc: &mut DefaultRsc<Self>,
+        render: &mut UiRenderState,
+    ) {
+    }
     #[allow(unused_variables)]
-    fn exit(&mut self, rsc: &mut DefaultRsc<Self>) {}
+    fn exit(&mut self, rsc: &mut DefaultRsc<Self>, render: &mut UiRenderState) {}
     #[allow(unused_variables)]
-    fn window_event(&mut self, event: WindowEvent, rsc: &mut DefaultRsc<Self>) {}
+    fn window_event(
+        &mut self,
+        event: WindowEvent,
+        rsc: &mut DefaultRsc<Self>,
+        render: &mut UiRenderState,
+    ) {
+    }
     fn window_attributes() -> WindowAttributes {
         Default::default()
     }
 }
 
 pub struct DefaultRsc<State: 'static> {
-    pub ui: Ui,
+    pub ui: UiData,
     pub events: EventManager<Self>,
     pub tasks: Tasks<Self>,
     _state: PhantomData<State>,
@@ -96,14 +116,26 @@ impl<State> DefaultRsc<State> {
     }
 }
 
-impl<State> HasUi for DefaultRsc<State> {
-    fn ui(&self) -> &Ui {
+impl<State> UiRsc for DefaultRsc<State> {
+    fn ui(&self) -> &UiData {
         &self.ui
     }
 
-    fn ui_mut(&mut self) -> &mut Ui {
+    fn ui_mut(&mut self) -> &mut UiData {
         &mut self.ui
     }
+
+    fn on_draw(&mut self, active: &ActiveData) {
+        self.events.draw(active);
+    }
+
+    fn on_undraw(&mut self, active: &ActiveData) {
+        self.events.undraw(active);
+    }
+
+    fn on_remove(&mut self, id: WidgetId) {
+        self.events.remove(id);
+    }
 }
 
 impl<State: 'static> HasState for DefaultRsc<State> {
@@ -128,6 +160,7 @@ impl<State: 'static> HasTasks for DefaultRsc<State> {
 
 pub struct DefaultApp<State: DefaultAppState> {
     rsc: DefaultRsc<State>,
+    render: UiRenderState,
     state: State,
     task_recv: TaskMsgReceiver<DefaultRsc<State>>,
 }
@@ -142,23 +175,32 @@ impl<State: DefaultAppState> AppState for DefaultApp<State> {
         let default_state = DefaultUiState::new(window);
         let (mut rsc, task_recv) = DefaultRsc::init(default_state.window.clone());
         let state = State::new(default_state, &mut rsc, proxy);
+        let render = UiRenderState::new();
         Self {
             rsc,
             state,
+            render,
             task_recv,
         }
     }
 
     fn event(&mut self, event: Self::Event, _: &ActiveEventLoop) {
-        self.state.event(event, &mut self.rsc);
+        self.state.event(event, &mut self.rsc, &mut self.render);
     }
 
     fn window_event(&mut self, event: WindowEvent, event_loop: &ActiveEventLoop) {
-        for update in self.task_recv.try_iter() {
-            update(&mut self.state, &mut self.rsc);
+        let Self {
+            rsc,
+            render,
+            state,
+            task_recv,
+        } = self;
+
+        for update in task_recv.try_iter() {
+            update(state, rsc);
         }
 
-        let ui_state = self.state.default_state_mut();
+        let ui_state = state.default_state_mut();
         let input_changed = ui_state.input.event(&event);
         let cursor_state = ui_state.cursor_state().clone();
         let old = ui_state.focus;
@@ -167,45 +209,43 @@ impl<State: DefaultAppState> AppState for DefaultApp<State> {
         }
         if input_changed {
             let window_size = ui_state.window_size();
-            self.rsc
-                .run_sensors(&mut self.state, cursor_state, window_size);
+            render.run_sensors(rsc, state, cursor_state, window_size);
         }
-        let ui = &mut self.rsc.ui;
-        let ui_state = self.state.default_state_mut();
+        let ui_state = state.default_state_mut();
         if old != ui_state.focus
             && let Some(old) = old
         {
-            old.edit(ui).deselect();
+            old.edit(rsc).deselect();
         }
         match &event {
             WindowEvent::CloseRequested => event_loop.exit(),
             WindowEvent::RedrawRequested => {
-                ui.update(&mut self.rsc.events);
-                ui_state.renderer.update(ui);
+                render.update(&ui_state.root, rsc);
+                ui_state.renderer.update(&mut rsc.ui, render);
                 ui_state.renderer.draw();
             }
             WindowEvent::Resized(size) => {
-                ui.resize((size.width, size.height));
+                render.resize((size.width, size.height));
                 ui_state.renderer.resize(size)
             }
             WindowEvent::KeyboardInput { event, .. } => {
                 if let Some(sel) = ui_state.focus
                     && event.state.is_pressed()
                 {
-                    let mut text = sel.edit(ui);
+                    let mut text = sel.edit(rsc);
                     match text.apply_event(event, &ui_state.input.modifiers) {
                         TextInputResult::Unfocus => {
                             ui_state.focus = None;
                             ui_state.window.set_ime_allowed(false);
                         }
                         TextInputResult::Submit => {
-                            self.rsc.run_event::<Submit>(sel, (), &mut self.state);
+                            rsc.run_event::<Submit>(sel, (), state);
                         }
                         TextInputResult::Paste => {
                             if let Ok(t) = ui_state.clipboard.get_text() {
                                 text.insert(&t);
                             }
-                            self.rsc.run_event::<Edited>(sel, (), &mut self.state);
+                            rsc.run_event::<Edited>(sel, (), state);
                         }
                         TextInputResult::Copy(text) => {
                             if let Err(err) = ui_state.clipboard.set_text(text) {
@@ -213,7 +253,7 @@ impl<State: DefaultAppState> AppState for DefaultApp<State> {
                             }
                         }
                         TextInputResult::Used => {
-                            self.rsc.run_event::<Edited>(sel, (), &mut self.state);
+                            rsc.run_event::<Edited>(sel, (), state);
                         }
                         TextInputResult::Unused => {}
                     }
@@ -221,7 +261,7 @@ impl<State: DefaultAppState> AppState for DefaultApp<State> {
             }
             WindowEvent::Ime(ime) => {
                 if let Some(sel) = ui_state.focus {
-                    let mut text = sel.edit(ui);
+                    let mut text = sel.edit(rsc);
                     match ime {
                         Ime::Enabled | Ime::Disabled => (),
                         Ime::Preedit(content, _pos) => {
@@ -237,15 +277,15 @@ impl<State: DefaultAppState> AppState for DefaultApp<State> {
             }
             _ => (),
         }
-        self.state.window_event(event, &mut self.rsc);
+        state.window_event(event, rsc, render);
         let ui_state = self.state.default_state_mut();
-        if self.rsc.ui.needs_redraw() {
+        if render.needs_redraw(&ui_state.root, rsc.widgets()) {
             ui_state.renderer.window().request_redraw();
         }
         ui_state.input.end_frame();
     }
 
     fn exit(&mut self) {
-        self.state.exit(&mut self.rsc);
+        self.state.exit(&mut self.rsc, &mut self.render);
     }
 }

src/default/render.rs

@@ -1,4 +1,4 @@
-use iris_core::{Ui, UiLimits, UiRenderNode};
+use iris_core::{UiData, UiLimits, UiRenderNode, UiRenderState};
 use pollster::FutureExt;
 use std::sync::Arc;
 use wgpu::*;
@@ -17,8 +17,8 @@ pub struct UiRenderer {
 }
 
 impl UiRenderer {
-    pub fn update(&mut self, ui: &mut Ui) {
-        self.ui.update(&self.device, &self.queue, ui);
+    pub fn update(&mut self, ui: &mut UiData, render: &mut UiRenderState) {
+        self.ui.update(&self.device, &self.queue, ui, render);
     }
 
     pub fn draw(&mut self) {

src/default/sense.rs

@@ -26,9 +26,9 @@ pub enum CursorSense {
 pub struct CursorSenses(Vec<CursorSense>);
 
 impl Event for CursorSenses {
-    type Data = CursorData;
+    type Data<'a> = CursorData<'a>;
     type State = SensorState;
-    fn should_run(&self, data: &Self::Data) -> Option<Self::Data> {
+    fn should_run<'a>(&self, data: &Self::Data<'a>) -> Option<Self::Data<'a>> {
         if let Some(sense) = should_run(self, &data.cursor, data.hover) {
             let mut data = data.clone();
             data.sense = sense;
@@ -129,7 +129,7 @@ pub struct SensorState {
 }
 
 #[derive(Clone)]
-pub struct CursorData {
+pub struct CursorData<'a> {
     /// where this widget was hit
     pub pos: Vec2,
     pub size: Vec2,
@@ -138,20 +138,36 @@ pub struct CursorData {
     pub cursor: CursorState,
     /// the first sense that triggered this
     pub sense: CursorSense,
+    pub render: &'a UiRenderState,
 }
 
-pub trait SensorUi<Rsc: HasEvents> {
-    fn run_sensors(&mut self, state: &mut Rsc::State, cursor: CursorState, window_size: Vec2);
+pub trait SensorUi {
+    fn run_sensors<Rsc: HasEvents>(
+        &self,
+        rsc: &mut Rsc,
+        state: &mut Rsc::State,
+        cursor: CursorState,
+        window_size: Vec2,
+    );
 }
 
-impl<Rsc: HasEvents> SensorUi<Rsc> for Rsc {
-    fn run_sensors(&mut self, state: &mut Rsc::State, cursor: CursorState, window_size: Vec2) {
-        let layers = std::mem::take(&mut self.ui_mut().layers);
-        let mut active = std::mem::take(&mut self.events_mut().get_type::<CursorSense>().active);
-        for layer in layers.indices().rev() {
+impl SensorUi for UiRenderState {
+    fn run_sensors<Rsc: HasEvents>(
+        &self,
+        rsc: &mut Rsc,
+        state: &mut Rsc::State,
+        cursor: CursorState,
+        window_size: Vec2,
+    ) {
+        // in order to remove this take, need to store active list in UiRenderState somehow
+        // this would probably be done through a generic parameter that adds yet another rsc /
+        // state like thing, but local to render state, and is passed to UiRsc events so you can
+        // update it there?
+        let mut active = std::mem::take(&mut rsc.events_mut().get_type::<CursorSense>().active);
+        for layer in self.layers.indices().rev() {
             let mut sensed = false;
             for (id, sensor) in active.get_mut(&layer).into_flat_iter() {
-                let shape = self.ui().active.get(id).unwrap().region;
+                let shape = self.active.get(id).unwrap().region;
                 let region = shape.to_px(window_size);
                 let in_shape = cursor.exists && region.contains(cursor.pos);
                 sensor.hover.update(in_shape);
@@ -171,15 +187,15 @@ impl<Rsc: HasEvents> SensorUi<Rsc> for Rsc {
                     // this does not have any meaning;
                     // might wanna set up Event to have a prepare stage
                     sense: CursorSense::Hovering,
+                    render: self,
                 };
-                self.run_event::<CursorSense>(*id, data, state);
+                rsc.run_event::<CursorSense>(*id, data, state);
             }
             if sensed {
                 break;
             }
         }
-        self.events_mut().get_type::<CursorSense>().active = active;
-        self.ui_mut().layers = layers;
+        rsc.events_mut().get_type::<CursorSense>().active = active;
     }
 }
 

src/event.rs

@@ -2,13 +2,13 @@ use iris_core::*;
 use iris_macro::*;
 use std::sync::Arc;
 
-use crate::default::{TaskCtx, Tasks};
+use crate::default::{TaskCtx, TaskUpdate, Tasks};
 
 pub trait Eventable<Rsc: HasEvents, Tag>: WidgetLike<Rsc, Tag> {
     fn on<E: EventLike>(
         self,
         event: E,
-        f: impl WidgetEventFn<Rsc, <E::Event as Event>::Data, Self::Widget>,
+        f: impl for<'a> WidgetEventFn<Rsc, <E::Event as Event>::Data<'a>, Self::Widget>,
     ) -> impl WidgetIdFn<Rsc, Self::Widget> {
         move |rsc| {
             let id = self.add(rsc);
@@ -30,24 +30,22 @@ impl<WL: WidgetLike<Rsc, Tag>, Rsc: HasEvents, Tag> Eventable<Rsc, Tag> for WL {
 
 widget_trait! {
     pub trait TaskEventable<Rsc: HasEvents + HasTasks>;
-    fn task_on<E: EventLike, F: AsyncWidgetEventFn<Rsc, <E::Event as Event>::Data, WL::Widget>>(
+    fn task_on<'a, E: EventLike, F: AsyncWidgetEventFn<Rsc, WL::Widget>>(
         self,
         event: E,
         f: F,
     ) -> impl WidgetIdFn<Rsc, WL::Widget>
-        where <E::Event as Event>::Data: Send,
-        for<'a> F::CallRefFuture<'a>: Send,
+        where <E::Event as Event>::Data<'a>: Send,
+        for<'b> F::CallRefFuture<'b>: Send,
     {
         let f = Arc::new(f);
         move |rsc| {
             let id = self.add(rsc);
-            rsc.register_event(id, event.into_event(), move |ctx, rsc| {
-                let data = ctx.data;
+            rsc.register_event(id, event.into_event(), move |_, rsc| {
                 let f = f.clone();
                 rsc.tasks_mut().spawn(async move |task| {
                     f(AsyncEventIdCtx {
                         widget: id,
-                        data,
                         task,
                     }).await;
                 });
@@ -61,21 +59,22 @@ pub trait HasTasks: Sized + HasState + HasEvents {
     fn tasks_mut(&mut self) -> &mut Tasks<Self>;
 }
 
-pub trait AsyncWidgetEventFn<Rsc: HasEvents, Data, W: ?Sized>:
-    AsyncFn(AsyncEventIdCtx<Rsc, Data, W>) + Send + Sync + 'static
+pub trait AsyncWidgetEventFn<Rsc: HasEvents, W: ?Sized>:
+    AsyncFn(AsyncEventIdCtx<Rsc, W>) + Send + Sync + 'static
 {
 }
-impl<
-    Rsc: HasEvents,
-    F: AsyncFn(AsyncEventIdCtx<Rsc, Data, W>) + Send + Sync + 'static,
-    Data,
-    W: ?Sized,
-> AsyncWidgetEventFn<Rsc, Data, W> for F
+impl<Rsc: HasEvents, F: AsyncFn(AsyncEventIdCtx<Rsc, W>) + Send + Sync + 'static, W: ?Sized>
+    AsyncWidgetEventFn<Rsc, W> for F
 {
 }
 
-pub struct AsyncEventIdCtx<Rsc: HasEvents, Data, W: ?Sized> {
-    pub widget: WidgetRef<W>,
-    pub data: Data,
-    pub task: TaskCtx<Rsc>,
+pub struct AsyncEventIdCtx<Rsc: HasEvents, W: ?Sized> {
+    pub widget: WeakWidget<W>,
+    task: TaskCtx<Rsc>,
+}
+
+impl<Rsc: HasEvents, W: ?Sized> AsyncEventIdCtx<Rsc, W> {
+    pub fn update(&mut self, f: impl TaskUpdate<Rsc> + 'static) {
+        self.task.update(f);
+    }
 }

src/widget/image.rs

@@ -19,10 +19,10 @@ impl Widget for Image {
     }
 }
 
-pub fn image<State: HasUi>(image: impl LoadableImage) -> impl WidgetFn<State, Image> {
+pub fn image<State: UiRsc>(image: impl LoadableImage) -> impl WidgetFn<State, Image> {
     let image = image.get_image().expect("Failed to load image");
     move |state| Image {
-        handle: state.ui_mut().add_texture(image),
+        handle: state.ui_mut().textures.add(image),
     }
 }
 

src/widget/mask.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 
 pub struct Masked {
-    pub inner: WidgetHandle,
+    pub inner: StrongWidget,
 }
 
 impl Widget for Masked {

src/widget/position/align.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 
 pub struct Aligned {
-    pub inner: WidgetHandle,
+    pub inner: StrongWidget,
     pub align: Align,
 }
 

src/widget/position/layer.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 
 pub struct LayerOffset {
-    pub inner: WidgetHandle,
+    pub inner: StrongWidget,
     pub offset: usize,
 }
 

src/widget/position/max_size.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 
 pub struct MaxSize {
-    pub inner: WidgetHandle,
+    pub inner: StrongWidget,
     pub x: Option<Len>,
     pub y: Option<Len>,
 }

src/widget/position/offset.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 
 pub struct Offset {
-    pub inner: WidgetHandle,
+    pub inner: StrongWidget,
     pub amt: UiVec2,
 }
 

src/widget/position/pad.rs

@@ -2,7 +2,7 @@ use crate::prelude::*;
 
 pub struct Pad {
     pub padding: Padding,
-    pub inner: WidgetHandle,
+    pub inner: StrongWidget,
 }
 
 impl Widget for Pad {

src/widget/position/scroll.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 
 pub struct Scroll {
-    inner: WidgetHandle,
+    inner: StrongWidget,
     axis: Axis,
     amt: f32,
     snap_end: bool,
@@ -41,7 +41,7 @@ impl Widget for Scroll {
 }
 
 impl Scroll {
-    pub fn new(inner: WidgetHandle, axis: Axis) -> Self {
+    pub fn new(inner: StrongWidget, axis: Axis) -> Self {
         Self {
             inner,
             axis,

src/widget/position/sized.rs

@@ -1,7 +1,7 @@
 use crate::prelude::*;
 
 pub struct Sized {
-    pub inner: WidgetHandle,
+    pub inner: StrongWidget,
     pub x: Option<Len>,
     pub y: Option<Len>,
 }

src/widget/position/span.rs

@@ -2,7 +2,7 @@ use crate::prelude::*;
 use std::marker::PhantomData;
 
 pub struct Span {
-    pub children: Vec<WidgetHandle>,
+    pub children: Vec<StrongWidget>,
     pub dir: Dir,
     pub gap: f32,
 }
@@ -62,11 +62,11 @@ impl Span {
         self
     }
 
-    pub fn push(&mut self, w: WidgetHandle) {
+    pub fn push(&mut self, w: StrongWidget) {
         self.children.push(w);
     }
 
-    pub fn pop(&mut self) -> Option<WidgetHandle> {
+    pub fn pop(&mut self) -> Option<StrongWidget> {
         self.children.pop()
     }
 
@@ -193,7 +193,7 @@ impl<State, const LEN: usize, Wa: WidgetArrLike<State, LEN, Tag>, Tag>
 }
 
 impl std::ops::Deref for Span {
-    type Target = Vec<WidgetHandle>;
+    type Target = Vec<StrongWidget>;
 
     fn deref(&self) -> &Self::Target {
         &self.children

src/widget/position/stack.rs

@@ -3,7 +3,7 @@ use std::marker::PhantomData;
 use crate::prelude::*;
 
 pub struct Stack {
-    pub children: Vec<WidgetHandle>,
+    pub children: Vec<StrongWidget>,
     pub size: StackSize,
 }
 

src/widget/ptr.rs

@@ -2,7 +2,7 @@ use crate::prelude::*;
 use std::marker::{Sized, Unsize};
 
 pub struct WidgetPtr {
-    pub inner: Option<WidgetHandle>,
+    pub inner: Option<StrongWidget>,
 }
 
 impl Widget for WidgetPtr {
@@ -38,14 +38,14 @@ impl WidgetPtr {
             inner: Default::default(),
         }
     }
-    pub fn set<W: ?Sized + Unsize<dyn Widget>>(&mut self, to: WidgetHandle<W>) {
+    pub fn set<W: ?Sized + Unsize<dyn Widget>>(&mut self, to: StrongWidget<W>) {
         self.inner = Some(to)
     }
 
     pub fn replace<W: ?Sized + Unsize<dyn Widget>>(
         &mut self,
-        to: WidgetHandle<W>,
-    ) -> Option<WidgetHandle> {
+        to: StrongWidget<W>,
+    ) -> Option<StrongWidget> {
         self.inner.replace(to)
     }
 }

src/widget/text/build.rs

@@ -51,7 +51,7 @@ impl<State, O, H: WidgetOption<State>> TextBuilder<State, O, H> {
     }
 }
 
-impl<Rsc: HasUi, O> TextBuilder<Rsc, O> {
+impl<Rsc: UiRsc, O> TextBuilder<Rsc, O> {
     pub fn hint<W: WidgetLike<Rsc, Tag>, Tag>(
         self,
         hint: W,
@@ -75,7 +75,7 @@ pub trait TextBuilderOutput<State>: Sized {
 }
 
 pub struct TextOutput;
-impl<Rsc: HasUi> TextBuilderOutput<Rsc> for TextOutput {
+impl<Rsc: UiRsc> TextBuilderOutput<Rsc> for TextOutput {
     type Output = Text;
 
     fn run<H: WidgetOption<Rsc>>(
@@ -103,7 +103,7 @@ pub struct TextEditOutput {
     mode: EditMode,
 }
 
-impl<State: HasUi> TextBuilderOutput<State> for TextEditOutput {
+impl<State: UiRsc> TextBuilderOutput<State> for TextEditOutput {
     type Output = TextEdit;
 
     fn run<H: WidgetOption<State>>(

src/widget/text/edit.rs

@@ -617,11 +617,11 @@ impl DerefMut for TextEdit {
 }
 
 pub trait TextEditable {
-    fn edit<'a>(&self, ui: &'a mut impl HasUi) -> TextEditCtx<'a>;
+    fn edit<'a>(&self, ui: &'a mut impl UiRsc) -> TextEditCtx<'a>;
 }
 
 impl<I: IdLike<Widget = TextEdit>> TextEditable for I {
-    fn edit<'a>(&self, ui: &'a mut impl HasUi) -> TextEditCtx<'a> {
+    fn edit<'a>(&self, ui: &'a mut impl UiRsc) -> TextEditCtx<'a> {
         let ui = ui.ui_mut();
         TextEditCtx {
             text: ui.widgets.get_mut(self).unwrap(),

src/widget/text/mod.rs

@@ -22,11 +22,11 @@ pub struct TextView {
     // cache
     tex: Option<RenderedText>,
     width: Option<f32>,
-    pub hint: Option<WidgetHandle>,
+    pub hint: Option<StrongWidget>,
 }
 
 impl TextView {
-    pub fn new(buf: TextBuffer, attrs: TextAttrs, hint: Option<WidgetHandle>) -> Self {
+    pub fn new(buf: TextBuffer, attrs: TextAttrs, hint: Option<StrongWidget>) -> Self {
         Self {
             attrs: attrs.into(),
             buf: buf.into(),

src/widget/trait_fns.rs

@@ -3,7 +3,7 @@ use crate::prelude::*;
 
 // these methods should "not require any context" (require unit) because they're in core
 widget_trait! {
-    pub trait CoreWidget<Rsc: HasUi + 'static>;
+    pub trait CoreWidget<Rsc: UiRsc + 'static>;
 
     fn pad(self, padding: impl Into<Padding>) -> impl WidgetFn<Rsc, Pad> {
         |state| Pad {
@@ -26,7 +26,7 @@ widget_trait! {
     fn label(self, label: impl Into<String>) -> impl WidgetIdFn<Rsc, WL::Widget> {
         |state| {
             let id = self.add(state);
-            state.ui_mut().set_label(id, label.into());
+            state.ui_mut().widgets.set_label(id, label.into());
             id
         }
     }
@@ -125,9 +125,9 @@ widget_trait! {
         |state| self.add(state)
     }
 
-    fn set_ptr(self, ptr: WidgetRef<WidgetPtr>, state: &mut Rsc) {
+    fn set_ptr(self, ptr: WeakWidget<WidgetPtr>, state: &mut Rsc) {
         let id = self.add_strong(state);
-        state.ui_mut()[ptr].inner = Some(id);
+        state.ui_mut().widgets[ptr].inner = Some(id);
     }
 }