diff --git a/src/mathx.rs b/src/mathx.rs
index fdf9165..b21a624 100644
--- a/src/mathx.rs
+++ b/src/mathx.rs
@@ -44,13 +44,22 @@ impl MatExt for Mat3 {
 	}
 }
 
+/// Represents a 2×2 matrix decomposed as O^T D O, where O is orthogonal and D is diagonal.
+///
+/// Not every matrix can be decomposed like this, only that of a symmetric bilinear function.
 #[derive(Copy, Clone, Debug, PartialEq)]
 pub struct Decomp2 {
+	/// The orthogonal part.
+	///
+	/// Using a non-orthogonal matrix will yield to incorrect results (but no UB).
 	pub ortho: Mat2,
+
+	/// The diagonal part.
 	pub diag: Vec2,
 }
 
 impl Decomp2 {
+	/// Computes the square of this, more efficiently than doing that with a matrix.
 	pub fn square(&self) -> Self {
 		Self {
 			ortho: self.ortho,
@@ -58,6 +67,7 @@ impl Decomp2 {
 		}
 	}
 
+	/// Computes the inverse of this, more efficiently than doing that with a matrix.
 	pub fn inverse(&self) -> Self {
 		Self {
 			ortho: self.ortho,