Add AZStd::lerp math function, based on C++20 (#3468)

* Add AZStd::lerp math function, based on c++20 Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * Add unit test for AZStd::lerp, based on libc++ ones Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * written a reduced set of lerp tests, but now the license is correct Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * Update Code/Framework/AzCore/AzCore/std/math.h Co-authored-by: lumberyard-employee-dm <56135373+lumberyard-employee-dm@users.noreply.github.com> Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * Update Code/Framework/AzCore/Tests/AZStd/Math.cpp Co-authored-by: lumberyard-employee-dm <56135373+lumberyard-employee-dm@users.noreply.github.com> Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * fix the github suggestion merge Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * Copy some AZ::Lerp tests to std::lerp test suite + clang-format Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * Cleanup lerp test cases Remove comments that suggested very heavy tests that required things like `for every t1..` Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * Fix unit test compilation issues Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * fix whitespace issue Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * Use `TypeParam` in TYPED_TEST Co-authored-by: lumberyard-employee-dm <56135373+lumberyard-employee-dm@users.noreply.github.com> Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * Remove unneeded new-lines Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> * remove unused infinity Signed-off-by: nemerle <96597+nemerle@users.noreply.github.com> Co-authored-by: lumberyard-employee-dm <56135373+lumberyard-employee-dm@users.noreply.github.com>
2021-10-11 12:55:24 +02:00
parent 7b1dd01d1d
commit b91d503a82
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+/*
+ * Copyright (c) Contributors to the Open 3D Engine Project.
+ * For complete copyright and license terms please see the LICENSE at the root of this distribution.
+ *
+ * SPDX-License-Identifier: Apache-2.0 OR MIT
+ *
+ */
+
+#include <AzCore/UnitTest/TestTypes.h>
+#include <AzCore/std/math.h>
+
+namespace UnitTest
+{
+    template<typename T>
+    class StdMathTest : public ::testing::Test
+    {
+    };
+
+    using MathTestConfigs = ::testing::Types<float, double, long double>;
+    TYPED_TEST_CASE(StdMathTest, MathTestConfigs);
+
+    TYPED_TEST(StdMathTest, LerpOperations)
+    {
+        using AZStd::lerp;
+        using ::testing::Eq;
+        using T = TypeParam;
+
+        constexpr T maxNumber = AZStd::numeric_limits<T>::max();
+        constexpr T eps = AZStd::numeric_limits<T>::epsilon();
+        constexpr T a{ 42 };
+
+        // exactness: lerp(a,b,0)==a && lerp(a,b,1)==b
+        EXPECT_THAT(lerp(eps, maxNumber, T(0)), Eq(eps));
+        EXPECT_THAT(lerp(eps, maxNumber, T(1)), Eq(maxNumber));
+
+        // consistency: lerp(a,a,t)==a
+        EXPECT_THAT(lerp(a, a, T(0.5)), Eq(a));
+        EXPECT_THAT(lerp(eps, eps, T(0.5)), Eq(eps));
+
+        // a few generic tests taken from MathUtilTests.cpp
+        EXPECT_EQ(T(2.5), lerp(T(2), T(4), T(0.25)));
+        EXPECT_EQ(T(6.0), lerp(T(2), T(4), T(2.0)));
+        EXPECT_EQ(T(3.5), lerp(T(2), T(4), T(0.75)));
+        EXPECT_EQ(T(0.0), lerp(T(2), T(4), T(-1.0)));
+    }
+} // namespace UnitTest