Use f32 in Length::Units and rename it to Fixed

core/src/pixels.rs

@@ -0,0 +1,22 @@
+/// An amount of logical pixels.
+///
+/// Normally used to represent an amount of space, or the size of something.
+///
+/// This type is normally asked as an argument in a generic way
+/// (e.g. `impl Into<Pixels>`) and, since `Pixels` implements `From` both for
+/// `f32` and `u16`, you should be able to provide both integers and float
+/// literals as needed.
+#[derive(Debug, Clone, Copy, PartialEq, PartialOrd)]
+pub struct Pixels(pub f32);
+
+impl From<f32> for Pixels {
+    fn from(amount: f32) -> Self {
+        Self(amount)
+    }
+}
+
+impl From<u16> for Pixels {
+    fn from(amount: u16) -> Self {
+        Self(f32::from(amount))
+    }
+}