XtalOptimizer: Refine rotation axis

common/GoniometerAxis.cpp

@@ -31,6 +31,20 @@ GoniometerAxis::GoniometerAxis(const std::string& in_name,
     helical_step = in_helical_step;
 }
 
+GoniometerAxis &GoniometerAxis::ScreeningWedge(const std::optional<float> &input) {
+    screening_wedge = input;
+    return *this;
+}
+
+GoniometerAxis &GoniometerAxis::Axis(const Coord &input) {
+    if (input.Length() == 0.0f)
+        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid,
+                              "Rotation axis cannot have 0 length");
+
+    axis = input.Normalize();
+    return *this;
+}
+
 std::string GoniometerAxis::GetName() const {
     return name;
 }
@@ -97,11 +111,6 @@ std::vector<double> GoniometerAxis::GetAngleContainer(int64_t max_image_number)
     return angle_container;
 }
 
-GoniometerAxis &GoniometerAxis::ScreeningWedge(const std::optional<float> &input) {
-    screening_wedge = input;
-    return *this;
-}
-
 std::optional<float> GoniometerAxis::GetScreeningWedge() const {
     return screening_wedge;
 }