refactor(output): group ops/ and space/

output/src/space/measure.rs

@@ -0,0 +1,87 @@
+use crate::*;
+use std::sync::{Arc, atomic::{AtomicUsize, Ordering::Relaxed}};
+
+pub trait HasSize<E: Output> {
+    fn size (&self) -> &Measure<E>;
+}
+
+#[macro_export] macro_rules! has_size {
+    (<$E:ty>|$self:ident:$Struct:ident$(<$($L:lifetime),*$($T:ident$(:$U:path)?),*>)?|$cb:expr) => {
+        impl $(<$($L),*$($T $(: $U)?),*>)? HasSize<$E> for $Struct $(<$($L),*$($T),*>)? {
+            fn size (&$self) -> &Measure<$E> { $cb }
+        }
+    }
+}
+
+/// A widget that tracks its render width and height
+#[derive(Default)]
+pub struct Measure<E: Output> {
+    _engine: PhantomData<E>,
+    pub x: Arc<AtomicUsize>,
+    pub y: Arc<AtomicUsize>,
+}
+
+// TODO: 🡘  🡙 ←🡙→ indicator to expand window when too small
+impl<E: Output> Content<E> for Measure<E> {
+    fn render (&self, to: &mut E) {
+        self.x.store(to.area().w().into(), Relaxed);
+        self.y.store(to.area().h().into(), Relaxed);
+    }
+}
+
+impl<E: Output> Clone for Measure<E> {
+    fn clone (&self) -> Self {
+        Self {
+            _engine: Default::default(),
+            x: self.x.clone(),
+            y: self.y.clone(),
+        }
+    }
+}
+
+impl<E: Output> std::fmt::Debug for Measure<E> {
+    fn fmt (&self, f: &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
+        f.debug_struct("Measure")
+            .field("width",  &self.x)
+            .field("height", &self.y)
+            .finish()
+    }
+}
+
+impl<E: Output> Measure<E> {
+    pub fn new () -> Self {
+        Self {
+            _engine: PhantomData::default(),
+            x: Arc::new(0.into()),
+            y: Arc::new(0.into()),
+        }
+    }
+    pub fn set_w (&self, w: impl Into<usize>) -> &Self {
+        self.x.store(w.into(), Relaxed);
+        self
+    }
+    pub fn set_h (&self, h: impl Into<usize>) -> &Self {
+        self.y.store(h.into(), Relaxed);
+        self
+    }
+    pub fn set_wh (&self, w: impl Into<usize>, h: impl Into<usize>) -> &Self {
+        self.set_w(w);
+        self.set_h(h);
+        self
+    }
+    pub fn w (&self) -> usize {
+        self.x.load(Relaxed)
+    }
+    pub fn h (&self) -> usize {
+        self.y.load(Relaxed)
+    }
+    pub fn wh (&self) -> [usize;2] {
+        [self.w(), self.h()]
+    }
+    pub fn format (&self) -> Arc<str> {
+        format!("{}x{}", self.w(), self.h()).into()
+    }
+    pub fn of <T: Content<E>> (&self, item: T) -> Bsp<Fill<&Self>, T> {
+        Bsp::b(Fill::xy(self), item)
+    }
+}