Switch back to custom geometry types, unified with layout primitives 🏞

1 files changed, 92 insertions, 0 deletions

diff --git a/src/geom/relative.rs b/src/geom/relative.rs
new file mode 100644
index 00000000..037c83dc
--- /dev/null
+++ b/src/geom/relative.rs
@@ -0,0 +1,92 @@
+use super::*;
+
+/// A relative length.
+///
+/// _Note_: `50%` is represented as `0.5` here, but stored as `50.0` in the
+/// corresponding [literal].
+///
+/// [literal]: ../syntax/ast/enum.Lit.html#variant.Percent
+#[derive(Default, Copy, Clone, PartialEq, PartialOrd)]
+pub struct Relative(f64);
+
+impl Relative {
+    /// A ratio of `0%` represented as `0.0`.
+    pub const ZERO: Self = Self(0.0);
+
+    /// A ratio of `100%` represented as `1.0`.
+    pub const ONE: Self = Self(1.0);
+
+    /// Create a new relative value.
+    pub fn new(ratio: f64) -> Self {
+        Self(ratio)
+    }
+
+    /// Get the underlying ratio.
+    pub fn get(self) -> f64 {
+        self.0
+    }
+
+    /// Evaluate the relative length with `one` being `100%`.
+    pub fn eval(self, one: Length) -> Length {
+        self.get() * one
+    }
+}
+
+impl Display for Relative {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        write!(f, "{:.2}%", self.0)
+    }
+}
+
+impl Debug for Relative {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        Display::fmt(self, f)
+    }
+}
+
+impl Neg for Relative {
+    type Output = Self;
+
+    fn neg(self) -> Self {
+        Self(-self.0)
+    }
+}
+
+impl Add for Relative {
+    type Output = Self;
+
+    fn add(self, other: Self) -> Self {
+        Self(self.0 + other.0)
+    }
+}
+
+sub_impl!(Relative - Relative -> Relative);
+
+impl Mul<f64> for Relative {
+    type Output = Self;
+
+    fn mul(self, other: f64) -> Self {
+        Self(self.0 * other)
+    }
+}
+
+impl Mul<Relative> for f64 {
+    type Output = Relative;
+
+    fn mul(self, other: Relative) -> Relative {
+        other * self
+    }
+}
+
+impl Div<f64> for Relative {
+    type Output = Self;
+
+    fn div(self, other: f64) -> Self {
+        Self(self.0 / other)
+    }
+}
+
+assign_impl!(Relative += Relative);
+assign_impl!(Relative -= Relative);
+assign_impl!(Relative *= f64);
+assign_impl!(Relative /= f64);