curve: Make Keyframe's 'value' member public.

libopenage/curve/keyframe.h

@@ -36,18 +36,37 @@ class Keyframe {
 		timestamp{time},
 		value{value} {}
 
+	/**
+	 * Get the time of this keyframe.
+	 *
+	 * @return Keyframe time.
+	 */
 	const time::time_t &time() const {
 		return this->timestamp;
 	}
 
+	/**
+	 * Get the value of this keyframe.
+	 *
+	 * @return Keyframe value.
+	 */
 	const T &val() const {
 		return this->value;
 	}
 
+public:
+	/**
+	 * Value of the keyframe.
+	 *
+	 * Can be modified by the curve if necessary.
+	 */
+	T value = T{};
+
 private:
+	/**
+	 * Time of the keyframe.
+	 */
 	time::time_t timestamp = time::TIME_MIN;
-
-	T value = T{};
 };
 
 } // namespace openage::curve