add f32quat negate

Author: yury

cidre/src/simd.rs

@@ -1492,6 +1492,14 @@ impl std::ops::Mul<f32quat> for f32quat {
     }
 }
 
+impl std::ops::Neg for f32quat {
+    type Output = f32quat;
+
+    fn neg(self) -> Self::Output {
+        self.negate()
+    }
+}
+
 #[derive(Debug, Copy, Clone, PartialEq)]
 #[allow(non_camel_case_types)]
 #[repr(transparent)]
@@ -1528,6 +1536,20 @@ impl f32quat {
         self.0.dot(&other.0)
     }
 
+    #[inline]
+    #[doc(alias = "simd_negate")]
+    pub fn negate(self) -> Self {
+        #[cfg(target_arch = "aarch64")]
+        {
+            Self(f32x4(unsafe { std::arch::aarch64::vnegq_f32(self.0.0) }))
+        }
+
+        #[cfg(not(target_arch = "aarch64"))]
+        {
+            Self(f32x4::with_xyzw(-self.x(), -self.y(), -self.z(), -self.w()))
+        }
+    }
+
     #[inline]
     pub fn with_angle(angle: f32, axis: f32x3) -> Self {
         let half_angle = angle * 0.5;
@@ -1919,6 +1941,14 @@ mod tests {
         assert_eq!(a.dot(&b), 70.0);
     }
 
+    #[test]
+    fn f32quat_negate() {
+        let q = f32quat(f32x4::with_xyzw(1.0, -2.0, 3.5, -4.0));
+        let expected = f32quat(f32x4::with_xyzw(-1.0, 2.0, -3.5, 4.0));
+        assert_eq!(q.negate(), expected);
+        assert_eq!(-q, expected);
+    }
+
     #[test]
     fn f32quat_mul_known_result() {
         let qx = f32quat::with_angle(std::f32::consts::FRAC_PI_2, f32x3::with_xyz(1.0, 0.0, 0.0));