Math: creating DualComplex from Vector2.

src/Math/DualComplex.h

@@ -88,6 +88,20 @@ template<class T> class DualComplex: public Dual<Complex<T>> {
          */
         inline constexpr /*implicit*/ DualComplex(const Complex<T>& real, const Complex<T>& dual): Dual<Complex<T>>(real, dual) {}
 
+        /**
+         * @brief Construct dual complex number from vector
+         *
+         * To be used in transformations later. @f[
+         *      \hat c = (0 + i1) + \epsilon(v_x + iv_y)
+         * @f]
+         * @todoc Remove workaround when Doxygen is predictable
+         */
+        #ifdef DOXYGEN_GENERATING_OUTPUT
+        inline constexpr explicit DualComplex(const Vector2<T>& vector);
+        #else
+        inline constexpr explicit DualComplex(const Vector2<T>& vector): Dual<Complex<T>>({}, Complex<T>(vector)) {}
+        #endif
+
         /**
          * @brief Rotation angle of dual complex number
          *

src/Math/Test/DualComplexTest.cpp

@@ -27,6 +27,7 @@ class DualComplexTest: public Corrade::TestSuite::Tester {
 
         void construct();
         void constructDefault();
+        void constructFromVector();
 
         void constExpressions();
 
@@ -59,6 +60,7 @@ typedef Math::Vector2<float> Vector2;
 DualComplexTest::DualComplexTest() {
     addTests(&DualComplexTest::construct,
              &DualComplexTest::constructDefault,
+             &DualComplexTest::constructFromVector,
 
              &DualComplexTest::constExpressions,
 
@@ -92,6 +94,10 @@ void DualComplexTest::constructDefault() {
     CORRADE_COMPARE(DualComplex().length(), 1.0f);
 }
 
+void DualComplexTest::constructFromVector() {
+    CORRADE_COMPARE(DualComplex(Vector2(1.5f, -3.0f)), DualComplex({1.0f, 0.0f}, {1.5f, -3.0f}));
+}
+
 void DualComplexTest::constExpressions() {
     /* Default constructor */
     constexpr DualComplex a;
@@ -101,6 +107,10 @@ void DualComplexTest::constExpressions() {
     constexpr DualComplex b({-1.0f, 2.5f}, {3.0f, -7.5f});
     CORRADE_COMPARE(b, DualComplex({-1.0f, 2.5f}, {3.0f, -7.5f}));
 
+    /* Vector constructor */
+    constexpr DualComplex c(Vector2(-3.0f, 7.5f));
+    CORRADE_COMPARE(c, DualComplex({}, {-3.0f, 7.5f}));
+
     /* Copy constructor */
     constexpr DualComplex d(b);
     CORRADE_COMPARE(d, DualComplex({-1.0f, 2.5f}, {3.0f, -7.5f}));