Make the Rust client the sole app

src/widget/layout/max_size.rs

@@ -0,0 +1,54 @@
+use crate::prelude::*;
+
+pub struct MaxSize {
+    pub inner: StrongWidget,
+    pub x: Option<Len>,
+    pub y: Option<Len>,
+}
+
+impl MaxSize {
+    fn clamp(len: Len, max: Option<Len>, output: f32, density: f32) -> Len {
+        let Some(max) = max else {
+            return len;
+        };
+        let len_px = len.apply_rest(density).to_abs(output);
+        let max_px = max.apply_rest(density).to_abs(output);
+        if len_px > max_px {
+            max.fold_dp(density)
+        } else {
+            len
+        }
+    }
+
+    fn clamp_region(offered_px: f32, max: Option<Len>, output: f32, density: f32) -> UiSpan {
+        let Some(max) = max else {
+            return UiSpan::FULL;
+        };
+        let max_scalar = max.apply_rest(density);
+        let max_px = max_scalar.to_abs(output);
+        if offered_px > max_px {
+            max_scalar.align(AxisAlign::Neg)
+        } else {
+            UiSpan::FULL
+        }
+    }
+}
+
+impl Widget for MaxSize {
+    fn draw(&mut self, painter: &mut Painter) {
+        let output = painter.output_size();
+        let density = painter.density();
+        let offered = painter.px_size();
+        let region = UiRegion {
+            x: Self::clamp_region(offered.x, self.x, output.x, density),
+            y: Self::clamp_region(offered.y, self.y, output.y, density),
+        };
+        let used = painter.widget_within(&self.inner, region).size();
+        let size = Size {
+            x: Self::clamp(used.x, self.x, output.x, density),
+            y: Self::clamp(used.y, self.y, output.y, density),
+        };
+        painter.place_used(&self.inner, size, UiRegion::FULL);
+        painter.set_size(size);
+    }
+}