positioning dir in core

src/core/positioning/sized.rs

@@ -0,0 +1,16 @@
+use crate::prelude::*;
+
+pub struct Sized {
+    pub inner: WidgetId,
+    pub size: Vec2,
+}
+
+impl Widget for Sized {
+    fn draw(&mut self, painter: &mut Painter) {
+        painter.widget(&self.inner);
+    }
+
+    fn desired_size(&mut self, _: &mut SizeCtx) -> UiVec2 {
+        UiVec2::abs(self.size)
+    }
+}