Add Normalize and Length nodes (#2837)

* Add vector length node

* Add normalize node

* Add comments

* Make normalize node safer for the user

node-graph/gmath-nodes/src/lib.rs

@@ -612,6 +612,20 @@ fn dot_product(_: impl Ctx, vector_a: DVec2, vector_b: DVec2) -> f64 {
 	vector_a.dot(vector_b)
 }
 
+/// Gets the length or magnitude of a vector.
+#[node_macro::node(category("Math: Vector"))]
+fn length(_: impl Ctx, vector: DVec2) -> f64 {
+	vector.length()
+}
+
+/// Scales the input vector to unit length while preserving it's direction. This is equivalent to dividing the input vector by it's own magnitude.
+///
+/// Returns zero when the input vector is zero.
+#[node_macro::node(category("Math: Vector"))]
+fn normalize(_: impl Ctx, vector: DVec2) -> DVec2 {
+	vector.normalize_or_zero()
+}
+
 #[cfg(test)]
 mod test {
 	use super::*;
@@ -625,6 +639,12 @@ mod test {
 		assert_eq!(dot_product((), vector_a, vector_b), 11.);
 	}
 
+	#[test]
+	pub fn length_function() {
+		let vector = DVec2::new(3., 4.);
+		assert_eq!(length((), vector), 5.);
+	}
+
 	#[test]
 	fn test_basic_expression() {
 		let result = math((), 0., "2 + 2".to_string(), 0.);