1 files changed, 72 insertions, 0 deletions
diff --git a/core/src/rotation.rs b/core/src/rotation.rs
new file mode 100644
index 00000000..afa8d79e
--- /dev/null
+++ b/core/src/rotation.rs
@@ -0,0 +1,72 @@
+//! Control the rotation of some content (like an image) within a space.
+use crate::{Degrees, Radians, Size};
+
+/// The strategy used to rotate the content.
+///
+/// This is used to control the behavior of the layout when the content is rotated
+/// by a certain angle.
+#[derive(Debug, Clone, Copy, PartialEq)]
+pub enum Rotation {
+    /// The element will float while rotating. The layout will be kept exactly as it was
+    /// before the rotation.
+    ///
+    /// This is especially useful when used for animations, as it will avoid the
+    /// layout being shifted or resized when smoothly i.e. an icon.
+    ///
+    /// This is the default.
+    Floating(Radians),
+    /// The element will be solid while rotating. The layout will be adjusted to fit
+    /// the rotated content.
+    ///
+    /// This allows you to rotate an image and have the layout adjust to fit the new
+    /// size of the image.
+    Solid(Radians),
+}
+
+impl Rotation {
+    /// Returns the angle of the [`Rotation`] in [`Radians`].
+    pub fn radians(self) -> Radians {
+        match self {
+            Rotation::Floating(radians) | Rotation::Solid(radians) => radians,
+        }
+    }
+
+    /// Returns a mutable reference to the angle of the [`Rotation`] in [`Radians`].
+    pub fn radians_mut(&mut self) -> &mut Radians {
+        match self {
+            Rotation::Floating(radians) | Rotation::Solid(radians) => radians,
+        }
+    }
+
+    /// Returns the angle of the [`Rotation`] in [`Degrees`].
+    pub fn degrees(self) -> Degrees {
+        Degrees(self.radians().0.to_degrees())
+    }
+
+    /// Applies the [`Rotation`] to the given [`Size`], returning
+    /// the minimum [`Size`] containing the rotated one.
+    pub fn apply(self, size: Size) -> Size {
+        match self {
+            Self::Floating(_) => size,
+            Self::Solid(rotation) => size.rotate(rotation),
+        }
+    }
+}
+
+impl Default for Rotation {
+    fn default() -> Self {
+        Self::Floating(Radians(0.0))
+    }
+}
+
+impl From<Radians> for Rotation {
+    fn from(radians: Radians) -> Self {
+        Self::Floating(radians)
+    }
+}
+
+impl From<f32> for Rotation {
+    fn from(radians: f32) -> Self {
+        Self::Floating(Radians(radians))
+    }
+}