Fixed triangle obtuseness and moved it to tests.

src/typed-geometry/detail/functions.hh

@@ -44,6 +44,5 @@
 #include <typed-geometry/functions/subvector.hh>
 #include <typed-geometry/functions/tangent.hh>
 #include <typed-geometry/functions/translation.hh>
-#include <typed-geometry/functions/triangle.hh>
 #include <typed-geometry/functions/uniform.hh>
 #include <typed-geometry/functions/volume.hh>

src/typed-geometry/detail/utility.hh

@@ -254,4 +254,12 @@ struct identity_fun
     }
 };
 
+template <class T>
+void swap(T& a, T& b)
+{
+    T tmp = static_cast<T&&>(a);
+    a = static_cast<T&&>(b);
+    b = static_cast<T&&>(tmp);
+}
+
 } // namespace tg

src/typed-geometry/functions/triangle.hh → src/typed-geometry/tests/triangle_tests.hh

 #pragma once
 
+#include <typed-geometry/detail/utility.hh>
 #include <typed-geometry/functions/distance.hh>
 #include <typed-geometry/types/objects/triangle.hh>
 
 namespace tg
 {
-enum class obtuseness_class
+enum class triangle_obtuseness
 {
-    obtuse,   // one angle > 90°
-    right,    // one angle = 90°
-    nonobtuse // all angles < 90° (aka acute)
+    obtuse, // largest angle > 90°
+    right,  // largest angle = 90°
+    acute   // largest angles < 90°
 };
 
 template <int D, class ScalarT>
-TG_NODISCARD constexpr obtuseness_class triangle_obtuseness(triangle<D, ScalarT> const& t)
+TG_NODISCARD constexpr triangle_obtuseness classify_obtuseness(triangle<D, ScalarT> const& t)
 {
-    auto e0sqr = tg::distance(t.pos0, t.pos1);
-    auto e1sqr = tg::distance(t.pos1, t.pos2);
-    auto e2sqr = tg::distance(t.pos2, t.pos0);
+    auto e0sqr = tg::distance_sqr(t.pos0, t.pos1);
+    auto e1sqr = tg::distance_sqr(t.pos1, t.pos2);
+    auto e2sqr = tg::distance_sqr(t.pos2, t.pos0);
 
     // make e0sqr longest (squared) edge
     if (e1sqr > e0sqr)
-        std::swap(e0sqr, e1sqr);
+        tg::swap(e0sqr, e1sqr);
     if (e2sqr > e0sqr)
-        std::swap(e0sqr, e2sqr);
+        tg::swap(e0sqr, e2sqr);
 
     auto test = e0sqr - e1sqr - e2sqr;
     if (test > ScalarT(0))
-        return obtuseness_class::obtuse;
+        return triangle_obtuseness::obtuse;
     if (test < ScalarT(0))
-        return obtuseness_class::nonobtuse;
-    return obtuseness_class::right;
+        return triangle_obtuseness::acute;
+    return triangle_obtuseness::right;
 }
 
 template <int D, class ScalarT>
-TG_NODISCARD constexpr obtuseness_class is_obtuse_triangle(triangle<D, ScalarT> const& t)
+TG_NODISCARD constexpr triangle_obtuseness is_obtuse_triangle(triangle<D, ScalarT> const& t)
 {
-    return triangle_obtuseness(t) == obtuseness_class::obtuse;
+    return classify_obtuseness(t) == triangle_obtuseness::obtuse;
 }
 
 template <int D, class ScalarT>
-TG_NODISCARD constexpr obtuseness_class is_right_triangle(triangle<D, ScalarT> const& t)
+TG_NODISCARD constexpr triangle_obtuseness is_right_triangle(triangle<D, ScalarT> const& t)
 {
-    return triangle_obtuseness(t) == obtuseness_class::right;
+    return classify_obtuseness(t) == triangle_obtuseness::right;
 }
 
 template <int D, class ScalarT>
-TG_NODISCARD constexpr obtuseness_class is_nonobtuse_triangle(triangle<D, ScalarT> const& t)
+TG_NODISCARD constexpr triangle_obtuseness is_nonobtuse_triangle(triangle<D, ScalarT> const& t)
 {
-    return triangle_obtuseness(t) == obtuseness_class::nonobtuse;
+    return classify_obtuseness(t) != triangle_obtuseness::obtuse;
 }
 
 template <int D, class ScalarT>
-TG_NODISCARD constexpr obtuseness_class is_acute_triangle(triangle<D, ScalarT> const& t)
+TG_NODISCARD constexpr triangle_obtuseness is_acute_triangle(triangle<D, ScalarT> const& t)
 {
-    return is_nonobtuse_triangle(t);
+    return classify_obtuseness(t) == triangle_obtuseness::acute;
 }
 }