Added spaceship operator.

glm/gtx/spaceship.hpp

@@ -0,0 +1,33 @@
+
+#pragma once
+
+#include <compare>
+#include "../detail/qualifier.hpp"
+#include "../detail/setup.hpp"
+
+namespace glm
+{
+    template<length_t l, typename T, qualifier q>
+    GLM_FUNC_DECL GLM_CONSTEXPR std::strong_ordering operator<=>(const glm::vec<l, T, q>& left, const glm::vec<l, T, q>& right)
+    {
+        if (left[0] != right[0]) {
+            return left[0] <=> right[0];
+        }
+        if constexpr (l > 1) {
+            if (left[1] != right[1]) {
+                return left[1] <=> right[1];
+            }
+        }
+        if constexpr (l > 2) {
+            if (left[2] != right[2]) {
+                return left[2] <=> right[2];
+            }
+        }
+        if constexpr (l > 3) {
+            if (left[3] != right[3]) {
+                return left[3] <=> right[3];
+            }
+        }
+        return std::strong_ordering::equal;
+    }
+}