python: expose Constants.

Only the double variants (since Python doesn't really differentiate
between 32bit and 64bit floats) and directly into math to mimic Python's
math module.

src/python/magnum/math.cpp

@@ -171,6 +171,19 @@ void math(py::module& root, py::module& m) {
     boolVector(boolVector2);
     boolVector(boolVector3);
     boolVector(boolVector4);
+
+    /* Constants. Putting them into math like Python does and as doubles, since
+       Python doesn't really differentiate between 32bit and 64bit floats */
+    m.attr("pi") = Constantsd::pi();
+    m.attr("pi_half") = Constantsd::piHalf();
+    m.attr("pi_quarter") = Constantsd::piQuarter();
+    m.attr("tau") = Constantsd::tau();
+    m.attr("e") = Constantsd::e();
+    m.attr("sqrt2") = Constantsd::sqrt2();
+    m.attr("sqrt3") = Constantsd::sqrt3();
+    m.attr("sqrt_half") = Constantsd::sqrtHalf();
+    m.attr("nan") = Constantsd::nan();
+    m.attr("inf") = Constantsd::inf();
 }
 
 }

src/python/magnum/test/test_math.py

@@ -38,7 +38,7 @@ class Angle(unittest.TestCase):
         self.assertEqual(c, Deg(90.0))
 
     def test_conversion(self):
-        self.assertEqual(Rad(Deg(90.0)), Rad(1.570796326794896))
+        self.assertEqual(Rad(Deg(90.0)), Rad(math.pi_half))
 
     def test_ops(self):
         self.assertEqual(-Deg(30.0), Deg(-30.0))
@@ -97,3 +97,8 @@ class BoolVector(unittest.TestCase):
 
     def test_repr(self):
         self.assertEqual(repr(BoolVector4(0b0101)), 'BoolVector(0b0101)')
+
+class Constants(unittest.TestCase):
+    def test(self):
+        self.assertAlmostEqual(math.sqrt2**2, 2.0, 6)
+        self.assertAlmostEqual(math.sqrt3**2, 3.0)