coords/ops: add ceil for coords

coord/ops.hpp

@@ -1400,10 +1400,26 @@ namespace cruft {
     }
 
 
+    //-------------------------------------------------------------------------
+    template <
+        typename K,
+        typename = std::enable_if_t<
+            is_coord_v<K> && std::is_floating_point_v<typename K::value_type>
+        >
+    > constexpr auto
+    ceil (K const &k)
+    {
+        K res {};
+        for (std::size_t i = 0; i < K::elements; ++i)
+            res[i] = std::ceil (k[i]);
+        return res;
+    }
+
+
     ///------------------------------------------------------------------------
     /// Return the fractional part of a real value.
     ///
-    /// This is an extraodinarily naive implementation. We avoid doing
+    /// This is an extraordinarily naive implementation. We avoid doing
     /// explicit casts here in the hope that floor and sub is more efficient
     /// (ie, keeps floats as floats in registers).
     template <