added vscode config

Feature/engine units to metric

.vscode/launch.json

@@ -0,0 +1,24 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": " Unit Tests (Debug)",
+            "type": "lldb",
+            "request": "launch",
+            "program": "${workspaceRoot}/out/Debug/unit_tests",
+            "args": [],
+            "cwd": "${workspaceRoot}"
+        },
+        {
+            "name": " Unit Tests (Release)",
+            "type": "lldb",
+            "request": "launch",
+            "program": "${workspaceRoot}/out/Release/unit_tests",
+            "args": [],
+            "cwd": "${workspaceRoot}"
+        }
+    ]
+}

examples/CMakeLists.txt

@@ -29,7 +29,7 @@ set_target_properties(
 find_package(OpenGL)
 find_package(GLEW REQUIRED)
 find_package(glfw3 CONFIG REQUIRED)
-target_link_libraries(example_glfw3 PRIVATE omath::omath GLEW::GLEW glfw OpenGL::OpenGL)
+target_link_libraries(example_glfw3 PRIVATE omath::omath GLEW::GLEW glfw OpenGL::GL)
 
 if(OMATH_ENABLE_VALGRIND)
     omath_setup_valgrind(example_projection_matrix_builder)

include/omath/engines/frostbite_engine/formulas.hpp

@@ -23,4 +23,52 @@ namespace omath::frostbite_engine
 
     [[nodiscard]]
     Mat4X4 calc_perspective_projection_matrix(float field_of_view, float aspect_ratio, float near, float far) noexcept;
-} // namespace omath::unity_engine
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_centimeters(const FloatingType& units)
+    {
+        return units / static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_meters(const FloatingType& units)
+    {
+        return units;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_kilometers(const FloatingType& units)
+    {
+        return units_to_meters(units) / static_cast<FloatingType>(1000);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType centimeters_to_units(const FloatingType& centimeters)
+    {
+        return centimeters * static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType meters_to_units(const FloatingType& meters)
+    {
+        return meters;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType kilometers_to_units(const FloatingType& kilometers)
+    {
+        return meters_to_units(kilometers * static_cast<FloatingType>(1000));
+    }
+} // namespace omath::frostbite_engine

include/omath/engines/iw_engine/formulas.hpp

@@ -23,4 +23,54 @@ namespace omath::iw_engine
 
     [[nodiscard]]
     Mat4X4 calc_perspective_projection_matrix(float field_of_view, float aspect_ratio, float near, float far) noexcept;
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_centimeters(const FloatingType& units)
+    {
+        constexpr auto centimeter_in_unit = static_cast<FloatingType>(2.54);
+        return units * centimeter_in_unit;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_meters(const FloatingType& units)
+    {
+        return units_to_centimeters(units) / static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_kilometers(const FloatingType& units)
+    {
+        return units_to_meters(units) / static_cast<FloatingType>(1000);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType centimeters_to_units(const FloatingType& centimeters)
+    {
+        constexpr auto centimeter_in_unit = static_cast<FloatingType>(2.54);
+        return centimeters / centimeter_in_unit;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType meters_to_units(const FloatingType& meters)
+    {
+        return centimeters_to_units(meters * static_cast<FloatingType>(100));
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType kilometers_to_units(const FloatingType& kilometers)
+    {
+        return meters_to_units(kilometers * static_cast<FloatingType>(1000));
+    }
 } // namespace omath::iw_engine

include/omath/engines/opengl_engine/formulas.hpp

@@ -4,7 +4,6 @@
 #pragma once
 #include "omath/engines/opengl_engine/constants.hpp"
 
-
 namespace omath::opengl_engine
 {
     [[nodiscard]]
@@ -23,4 +22,52 @@ namespace omath::opengl_engine
 
     [[nodiscard]]
     Mat4X4 calc_perspective_projection_matrix(float field_of_view, float aspect_ratio, float near, float far) noexcept;
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_centimeters(const FloatingType& units)
+    {
+        return units / static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_meters(const FloatingType& units)
+    {
+        return units;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_kilometers(const FloatingType& units)
+    {
+        return units_to_meters(units) / static_cast<FloatingType>(1000);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType centimeters_to_units(const FloatingType& centimeters)
+    {
+        return centimeters * static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType meters_to_units(const FloatingType& meters)
+    {
+        return meters;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType kilometers_to_units(const FloatingType& kilometers)
+    {
+        return meters_to_units(kilometers * static_cast<FloatingType>(1000));
+    }
 } // namespace omath::opengl_engine

include/omath/engines/source_engine/formulas.hpp

@@ -22,4 +22,54 @@ namespace omath::source_engine
 
     [[nodiscard]]
     Mat4X4 calc_perspective_projection_matrix(float field_of_view, float aspect_ratio, float near, float far) noexcept;
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_centimeters(const FloatingType& units)
+    {
+        constexpr auto centimeter_in_unit = static_cast<FloatingType>(2.54);
+        return units * centimeter_in_unit;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_meters(const FloatingType& units)
+    {
+        return units_to_centimeters(units) / static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_kilometers(const FloatingType& units)
+    {
+        return units_to_meters(units) / static_cast<FloatingType>(1000);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType centimeters_to_units(const FloatingType& centimeters)
+    {
+        constexpr auto centimeter_in_unit = static_cast<FloatingType>(2.54);
+        return centimeters / centimeter_in_unit;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType meters_to_units(const FloatingType& meters)
+    {
+        return centimeters_to_units(meters * static_cast<FloatingType>(100));
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType kilometers_to_units(const FloatingType& kilometers)
+    {
+        return meters_to_units(kilometers * static_cast<FloatingType>(1000));
+    }
 } // namespace omath::source_engine

include/omath/engines/unity_engine/formulas.hpp

@@ -23,4 +23,52 @@ namespace omath::unity_engine
 
     [[nodiscard]]
     Mat4X4 calc_perspective_projection_matrix(float field_of_view, float aspect_ratio, float near, float far) noexcept;
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_centimeters(const FloatingType& units)
+    {
+        return units / static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_meters(const FloatingType& units)
+    {
+        return units;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_kilometers(const FloatingType& units)
+    {
+        return units_to_meters(units) / static_cast<FloatingType>(1000);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType centimeters_to_units(const FloatingType& centimeters)
+    {
+        return centimeters * static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType meters_to_units(const FloatingType& meters)
+    {
+        return meters;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType kilometers_to_units(const FloatingType& kilometers)
+    {
+        return meters_to_units(kilometers * static_cast<FloatingType>(1000));
+    }
 } // namespace omath::unity_engine

include/omath/engines/unreal_engine/formulas.hpp

@@ -23,4 +23,52 @@ namespace omath::unreal_engine
 
     [[nodiscard]]
     Mat4X4 calc_perspective_projection_matrix(float field_of_view, float aspect_ratio, float near, float far) noexcept;
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_centimeters(const FloatingType& units)
+    {
+        return units;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_meters(const FloatingType& units)
+    {
+        return units / static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType units_to_kilometers(const FloatingType& units)
+    {
+        return units_to_meters(units) / static_cast<FloatingType>(1000);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType centimeters_to_units(const FloatingType& centimeters)
+    {
+        return centimeters;
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType meters_to_units(const FloatingType& meters)
+    {
+        return meters * static_cast<FloatingType>(100);
+    }
+
+    template<class FloatingType>
+    requires std::is_floating_point_v<FloatingType>
+    [[nodiscard]]
+    constexpr FloatingType kilometers_to_units(const FloatingType& kilometers)
+    {
+        return meters_to_units(kilometers * static_cast<FloatingType>(1000));
+    }
 } // namespace omath::unreal_engine

tests/engines/unit_test_frostbite_engine.cpp

@@ -8,6 +8,125 @@
 #include <print>
 #include <random>
 
+TEST(unit_test_frostbite_engine, UnitsToCentimeters_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::frostbite_engine::units_to_centimeters(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::frostbite_engine::units_to_centimeters(1.0f), 0.01f);
+    EXPECT_FLOAT_EQ(omath::frostbite_engine::units_to_centimeters(100.0f), 1.0f);
+    EXPECT_FLOAT_EQ(omath::frostbite_engine::units_to_centimeters(-250.0f), -2.5f);
+}
+
+TEST(unit_test_frostbite_engine, UnitsToMeters_BasicValues)
+{
+    EXPECT_DOUBLE_EQ(omath::frostbite_engine::units_to_meters(0.0), 0.0);
+    EXPECT_DOUBLE_EQ(omath::frostbite_engine::units_to_meters(1.0), 1.0);
+    EXPECT_DOUBLE_EQ(omath::frostbite_engine::units_to_meters(123.456), 123.456);
+    EXPECT_DOUBLE_EQ(omath::frostbite_engine::units_to_meters(-42.0), -42.0);
+}
+
+TEST(unit_test_frostbite_engine, UnitsToKilometers_BasicValues)
+{
+    EXPECT_NEAR(omath::frostbite_engine::units_to_kilometers(0.0), 0.0, 1e-15);
+    EXPECT_NEAR(omath::frostbite_engine::units_to_kilometers(1.0), 0.001, 1e-15);
+    EXPECT_NEAR(omath::frostbite_engine::units_to_kilometers(1000.0), 1.0, 1e-12);
+    EXPECT_NEAR(omath::frostbite_engine::units_to_kilometers(-2500.0), -2.5, 1e-12);
+}
+
+TEST(unit_test_frostbite_engine, CentimetersToUnits_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::frostbite_engine::centimeters_to_units(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::frostbite_engine::centimeters_to_units(0.01f), 1.0f);
+    EXPECT_FLOAT_EQ(omath::frostbite_engine::centimeters_to_units(1.0f), 100.0f);
+    EXPECT_FLOAT_EQ(omath::frostbite_engine::centimeters_to_units(-2.5f), -250.0f);
+}
+
+TEST(unit_test_frostbite_engine, MetersToUnits_BasicValues)
+{
+    EXPECT_DOUBLE_EQ(omath::frostbite_engine::meters_to_units(0.0), 0.0);
+    EXPECT_DOUBLE_EQ(omath::frostbite_engine::meters_to_units(1.0), 1.0);
+    EXPECT_DOUBLE_EQ(omath::frostbite_engine::meters_to_units(123.456), 123.456);
+    EXPECT_DOUBLE_EQ(omath::frostbite_engine::meters_to_units(-42.0), -42.0);
+}
+
+TEST(unit_test_frostbite_engine, KilometersToUnits_BasicValues)
+{
+    EXPECT_NEAR(omath::frostbite_engine::kilometers_to_units(0.0), 0.0, 1e-12);
+    EXPECT_NEAR(omath::frostbite_engine::kilometers_to_units(0.001), 1.0, 1e-12);
+    EXPECT_NEAR(omath::frostbite_engine::kilometers_to_units(1.0), 1000.0, 1e-9);
+    EXPECT_NEAR(omath::frostbite_engine::kilometers_to_units(-2.5), -2500.0, 1e-9);
+}
+
+TEST(unit_test_frostbite_engine, RoundTrip_UnitsCentimeters)
+{
+    constexpr float units_f = 12345.678f;
+    const auto cm_f = omath::frostbite_engine::units_to_centimeters(units_f);
+    const auto units_f_back = omath::frostbite_engine::centimeters_to_units(cm_f);
+    EXPECT_NEAR(units_f_back, units_f, 1e-3f);
+
+    constexpr double units_d = -987654.321;
+    const auto cm_d = omath::frostbite_engine::units_to_centimeters(units_d);
+    const auto units_d_back = omath::frostbite_engine::centimeters_to_units(cm_d);
+    EXPECT_NEAR(units_d_back, units_d, 1e-9);
+}
+
+TEST(unit_test_frostbite_engine, RoundTrip_UnitsMeters)
+{
+    constexpr float units_f = 5432.125f;
+    constexpr auto m_f = omath::frostbite_engine::units_to_meters(units_f);
+    constexpr auto units_f_back = omath::frostbite_engine::meters_to_units(m_f);
+    EXPECT_FLOAT_EQ(units_f_back, units_f);
+
+    constexpr double units_d = -123456.789;
+    constexpr auto m_d = omath::frostbite_engine::units_to_meters(units_d);
+    constexpr auto units_d_back = omath::frostbite_engine::meters_to_units(m_d);
+    EXPECT_DOUBLE_EQ(units_d_back, units_d);
+}
+
+TEST(unit_test_frostbite_engine, RoundTrip_UnitsKilometers)
+{
+    constexpr float units_f = 100000.0f;
+    constexpr auto km_f = omath::frostbite_engine::units_to_kilometers(units_f);
+    constexpr auto units_f_back = omath::frostbite_engine::kilometers_to_units(km_f);
+    EXPECT_NEAR(units_f_back, units_f, 1e-2f);
+
+    constexpr double units_d = -7654321.123;
+    constexpr auto km_d = omath::frostbite_engine::units_to_kilometers(units_d);
+    constexpr auto units_d_back = omath::frostbite_engine::kilometers_to_units(km_d);
+    EXPECT_NEAR(units_d_back, units_d, 1e-6);
+}
+
+TEST(unit_test_frostbite_engine, ConversionChainConsistency)
+{
+    const double units = 424242.42;
+
+    const auto cm_direct = omath::frostbite_engine::units_to_centimeters(units);
+    const auto cm_via_units = units / 100.0;
+    EXPECT_NEAR(cm_direct, cm_via_units, 1e-12);
+
+    const auto km_direct = omath::frostbite_engine::units_to_kilometers(units);
+    const auto km_via_meters = omath::frostbite_engine::units_to_meters(units) / 1000.0;
+    EXPECT_NEAR(km_direct, km_via_meters, 1e-12);
+}
+
+TEST(unit_test_frostbite_engine, SupportsFloatAndDouble)
+{
+    static_assert(std::is_same_v<decltype(omath::frostbite_engine::units_to_centimeters(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::frostbite_engine::units_to_centimeters(1.0)), double>);
+    static_assert(std::is_same_v<decltype(omath::frostbite_engine::meters_to_units(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::frostbite_engine::kilometers_to_units(1.0)), double>);
+}
+
+TEST(unit_test_frostbite_engine, ConstexprConversions)
+{
+    constexpr double units = 1000.0;
+    constexpr double cm = omath::frostbite_engine::units_to_centimeters(units);
+    constexpr double m = omath::frostbite_engine::units_to_meters(units);
+    constexpr double km = omath::frostbite_engine::units_to_kilometers(units);
+
+    static_assert(cm == 10.0, "units_to_centimeters constexpr failed");
+    static_assert(m == 1000.0, "units_to_meters constexpr failed");
+    static_assert(km == 1.0, "units_to_kilometers constexpr failed");
+}
 TEST(unit_test_frostbite_engine, ForwardVector)
 {
     const auto forward = omath::frostbite_engine::forward_vector({});

tests/engines/unit_test_open_gl.cpp

@@ -7,6 +7,125 @@
 #include <omath/engines/opengl_engine/formulas.hpp>
 #include <random>
 
+TEST(unit_test_opengl, UnitsToCentimeters_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::opengl_engine::units_to_centimeters(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::opengl_engine::units_to_centimeters(1.0f), 0.01f);
+    EXPECT_FLOAT_EQ(omath::opengl_engine::units_to_centimeters(100.0f), 1.0f);
+    EXPECT_FLOAT_EQ(omath::opengl_engine::units_to_centimeters(-250.0f), -2.5f);
+}
+
+TEST(unit_test_opengl, UnitsToMeters_BasicValues)
+{
+    EXPECT_DOUBLE_EQ(omath::opengl_engine::units_to_meters(0.0), 0.0);
+    EXPECT_DOUBLE_EQ(omath::opengl_engine::units_to_meters(1.0), 1.0);
+    EXPECT_DOUBLE_EQ(omath::opengl_engine::units_to_meters(123.456), 123.456);
+    EXPECT_DOUBLE_EQ(omath::opengl_engine::units_to_meters(-42.0), -42.0);
+}
+
+TEST(unit_test_opengl, UnitsToKilometers_BasicValues)
+{
+    EXPECT_NEAR(omath::opengl_engine::units_to_kilometers(0.0), 0.0, 1e-15);
+    EXPECT_NEAR(omath::opengl_engine::units_to_kilometers(1.0), 0.001, 1e-15);
+    EXPECT_NEAR(omath::opengl_engine::units_to_kilometers(1000.0), 1.0, 1e-12);
+    EXPECT_NEAR(omath::opengl_engine::units_to_kilometers(-2500.0), -2.5, 1e-12);
+}
+
+TEST(unit_test_opengl, CentimetersToUnits_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::opengl_engine::centimeters_to_units(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::opengl_engine::centimeters_to_units(0.01f), 1.0f);
+    EXPECT_FLOAT_EQ(omath::opengl_engine::centimeters_to_units(1.0f), 100.0f);
+    EXPECT_FLOAT_EQ(omath::opengl_engine::centimeters_to_units(-2.5f), -250.0f);
+}
+
+TEST(unit_test_opengl, MetersToUnits_BasicValues)
+{
+    EXPECT_DOUBLE_EQ(omath::opengl_engine::meters_to_units(0.0), 0.0);
+    EXPECT_DOUBLE_EQ(omath::opengl_engine::meters_to_units(1.0), 1.0);
+    EXPECT_DOUBLE_EQ(omath::opengl_engine::meters_to_units(123.456), 123.456);
+    EXPECT_DOUBLE_EQ(omath::opengl_engine::meters_to_units(-42.0), -42.0);
+}
+
+TEST(unit_test_opengl, KilometersToUnits_BasicValues)
+{
+    EXPECT_NEAR(omath::opengl_engine::kilometers_to_units(0.0), 0.0, 1e-12);
+    EXPECT_NEAR(omath::opengl_engine::kilometers_to_units(0.001), 1.0, 1e-12);
+    EXPECT_NEAR(omath::opengl_engine::kilometers_to_units(1.0), 1000.0, 1e-9);
+    EXPECT_NEAR(omath::opengl_engine::kilometers_to_units(-2.5), -2500.0, 1e-9);
+}
+
+TEST(unit_test_opengl, RoundTrip_UnitsCentimeters)
+{
+    constexpr float units_f = 12345.678f;
+    const auto cm_f = omath::opengl_engine::units_to_centimeters(units_f);
+    const auto units_f_back = omath::opengl_engine::centimeters_to_units(cm_f);
+    EXPECT_NEAR(units_f_back, units_f, 1e-3f);
+
+    constexpr double units_d = -987654.321;
+    const auto cm_d = omath::opengl_engine::units_to_centimeters(units_d);
+    const auto units_d_back = omath::opengl_engine::centimeters_to_units(cm_d);
+    EXPECT_NEAR(units_d_back, units_d, 1e-9);
+}
+
+TEST(unit_test_opengl, RoundTrip_UnitsMeters)
+{
+    constexpr float units_f = 5432.125f;
+    const auto m_f = omath::opengl_engine::units_to_meters(units_f);
+    const auto units_f_back = omath::opengl_engine::meters_to_units(m_f);
+    EXPECT_FLOAT_EQ(units_f_back, units_f);
+
+    constexpr double units_d = -123456.789;
+    const auto m_d = omath::opengl_engine::units_to_meters(units_d);
+    const auto units_d_back = omath::opengl_engine::meters_to_units(m_d);
+    EXPECT_DOUBLE_EQ(units_d_back, units_d);
+}
+
+TEST(unit_test_opengl, RoundTrip_UnitsKilometers)
+{
+    constexpr float units_f = 100000.0f;
+    const auto km_f = omath::opengl_engine::units_to_kilometers(units_f);
+    const auto units_f_back = omath::opengl_engine::kilometers_to_units(km_f);
+    EXPECT_NEAR(units_f_back, units_f, 1e-2f);
+
+    constexpr double units_d = -7654321.123;
+    const auto km_d = omath::opengl_engine::units_to_kilometers(units_d);
+    const auto units_d_back = omath::opengl_engine::kilometers_to_units(km_d);
+    EXPECT_NEAR(units_d_back, units_d, 1e-6);
+}
+
+TEST(unit_test_opengl, ConversionChainConsistency)
+{
+    const double units = 424242.42;
+
+    const auto cm_direct = omath::opengl_engine::units_to_centimeters(units);
+    const auto cm_via_units = units / 100.0;
+    EXPECT_NEAR(cm_direct, cm_via_units, 1e-12);
+
+    const auto km_direct = omath::opengl_engine::units_to_kilometers(units);
+    const auto km_via_meters = omath::opengl_engine::units_to_meters(units) / 1000.0;
+    EXPECT_NEAR(km_direct, km_via_meters, 1e-12);
+}
+
+TEST(unit_test_opengl, SupportsFloatAndDouble)
+{
+    static_assert(std::is_same_v<decltype(omath::opengl_engine::units_to_centimeters(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::opengl_engine::units_to_centimeters(1.0)), double>);
+    static_assert(std::is_same_v<decltype(omath::opengl_engine::meters_to_units(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::opengl_engine::kilometers_to_units(1.0)), double>);
+}
+
+TEST(unit_test_opengl, ConstexprConversions)
+{
+    constexpr double units = 1000.0;
+    constexpr double cm = omath::opengl_engine::units_to_centimeters(units);
+    constexpr double m = omath::opengl_engine::units_to_meters(units);
+    constexpr double km = omath::opengl_engine::units_to_kilometers(units);
+
+    static_assert(cm == 10.0, "units_to_centimeters constexpr failed");
+    static_assert(m == 1000.0, "units_to_meters constexpr failed");
+    static_assert(km == 1.0, "units_to_kilometers constexpr failed");
+}
 TEST(unit_test_opengl, ForwardVector)
 {
     const auto forward = omath::opengl_engine::forward_vector({});

tests/engines/unit_test_source_engine.cpp

@@ -7,6 +7,129 @@
 #include <omath/engines/source_engine/formulas.hpp>
 #include <random>
 
+TEST(unit_test_source_engine_units, HammerUnitsToCentimeters_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::source_engine::units_to_centimeters(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::source_engine::units_to_centimeters(1.0f), 2.54f);
+    EXPECT_FLOAT_EQ(omath::source_engine::units_to_centimeters(10.0f), 25.4f);
+    EXPECT_FLOAT_EQ(omath::source_engine::units_to_centimeters(-2.0f), -5.08f);
+}
+
+TEST(unit_test_source_engine_units, HammerUnitsToMeters_BasicValues)
+{
+    EXPECT_NEAR(omath::source_engine::units_to_meters(0.0), 0.0, 1e-12);
+    EXPECT_NEAR(omath::source_engine::units_to_meters(1.0), 0.0254, 1e-12);
+    EXPECT_NEAR(omath::source_engine::units_to_meters(100.0), 2.54, 1e-12);
+    EXPECT_NEAR(omath::source_engine::units_to_meters(-4.0), -0.1016, 1e-12);
+}
+
+TEST(unit_test_source_engine_units, HammerUnitsToKilometers_BasicValues)
+{
+    EXPECT_NEAR(omath::source_engine::units_to_kilometers(0.0), 0.0, 1e-15);
+    EXPECT_NEAR(omath::source_engine::units_to_kilometers(1.0), 0.0000254, 1e-15);
+    EXPECT_NEAR(omath::source_engine::units_to_kilometers(1000.0), 0.0254, 1e-15);
+    EXPECT_NEAR(omath::source_engine::units_to_kilometers(-10.0), -0.000254, 1e-15);
+}
+
+TEST(unit_test_source_engine_units, CentimetersToHammerUnits_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::source_engine::centimeters_to_units(0.0f), 0.0f);
+    EXPECT_NEAR(omath::source_engine::centimeters_to_units(2.54f), 1.0f, 1e-6f);
+    EXPECT_NEAR(omath::source_engine::centimeters_to_units(25.4f), 10.0f, 1e-5f);
+    EXPECT_NEAR(omath::source_engine::centimeters_to_units(-5.08f), -2.0f, 1e-6f);
+}
+
+TEST(unit_test_source_engine_units, MetersToHammerUnits_BasicValues)
+{
+    EXPECT_NEAR(omath::source_engine::meters_to_units(0.0), 0.0, 1e-12);
+    EXPECT_NEAR(omath::source_engine::meters_to_units(0.0254), 1.0, 1e-12);
+    EXPECT_NEAR(omath::source_engine::meters_to_units(2.54), 100.0, 1e-10);
+    EXPECT_NEAR(omath::source_engine::meters_to_units(-0.0508), -2.0, 1e-12);
+}
+
+TEST(unit_test_source_engine_units, KilometersToHammerUnits_BasicValues)
+{
+    EXPECT_NEAR(omath::source_engine::kilometers_to_units(0.0), 0.0, 1e-9);
+    EXPECT_NEAR(omath::source_engine::kilometers_to_units(0.0000254), 1.0, 1e-9);
+    EXPECT_NEAR(omath::source_engine::kilometers_to_units(0.00254), 100.0, 1e-7);
+    EXPECT_NEAR(omath::source_engine::kilometers_to_units(-0.0000508), -2.0, 1e-9);
+}
+
+TEST(unit_test_source_engine_units, RoundTrip_HammerToCentimetersToHammer)
+{
+    constexpr float hu_f = 123.456f;
+    constexpr auto cm_f = omath::source_engine::units_to_centimeters(hu_f);
+    constexpr auto hu_f_back = omath::source_engine::centimeters_to_units(cm_f);
+    EXPECT_NEAR(hu_f_back, hu_f, 1e-5f);
+
+    constexpr double hu_d = -98765.4321;
+    constexpr auto cm_d = omath::source_engine::units_to_centimeters(hu_d);
+    constexpr auto hu_d_back = omath::source_engine::centimeters_to_units(cm_d);
+    EXPECT_NEAR(hu_d_back, hu_d, 1e-10);
+}
+
+TEST(unit_test_source_engine_units, RoundTrip_HammerToMetersToHammer)
+{
+    constexpr float hu_f = 2500.25f;
+    constexpr auto m_f = omath::source_engine::units_to_meters(hu_f);
+    constexpr auto hu_f_back = omath::source_engine::meters_to_units(m_f);
+    EXPECT_NEAR(hu_f_back, hu_f, 1e-4f);
+
+    constexpr double hu_d = -42000.125;
+    constexpr auto m_d = omath::source_engine::units_to_meters(hu_d);
+    constexpr auto hu_d_back = omath::source_engine::meters_to_units(m_d);
+    EXPECT_NEAR(hu_d_back, hu_d, 1e-10);
+}
+
+TEST(unit_test_source_engine_units, RoundTrip_HammerToKilometersToHammer)
+{
+    constexpr float hu_f = 100000.0f;
+    constexpr auto km_f = omath::source_engine::units_to_kilometers(hu_f);
+    constexpr auto hu_f_back = omath::source_engine::kilometers_to_units(km_f);
+    EXPECT_NEAR(hu_f_back, hu_f, 1e-2f); // looser due to float scaling
+
+    constexpr double hu_d = -1234567.89;
+    constexpr auto km_d = omath::source_engine::units_to_kilometers(hu_d);
+    constexpr auto hu_d_back = omath::source_engine::kilometers_to_units(km_d);
+    EXPECT_NEAR(hu_d_back, hu_d, 1e-7);
+}
+
+TEST(unit_test_source_engine_units, ConversionChainConsistency)
+{
+    // hu -> cm -> m -> km should match direct helpers
+    constexpr auto hu = 54321.123;
+
+    constexpr auto cm = omath::source_engine::units_to_centimeters(hu);
+    constexpr auto m_via_cm = cm / 100.0;
+    constexpr auto km_via_cm = m_via_cm / 1000.0;
+
+    constexpr auto m_direct = omath::source_engine::units_to_meters(hu);
+    constexpr auto km_direct = omath::source_engine::units_to_kilometers(hu);
+
+    EXPECT_NEAR(m_direct, m_via_cm, 1e-12);
+    EXPECT_NEAR(km_direct, km_via_cm, 1e-15);
+}
+
+TEST(unit_test_source_engine_units, SupportsFloatAndDoubleTypes)
+{
+    static_assert(std::is_same_v<decltype(omath::source_engine::units_to_centimeters(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::source_engine::units_to_centimeters(1.0)), double>);
+    static_assert(std::is_same_v<decltype(omath::source_engine::meters_to_units(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::source_engine::kilometers_to_units(1.0)), double>);
+}
+
+TEST(unit_test_source_engine_units, ConstexprEvaluation)
+{
+    constexpr double hu = 10.0;
+    constexpr double cm = omath::source_engine::units_to_centimeters(hu);
+    constexpr double m = omath::source_engine::units_to_meters(hu);
+    constexpr double km = omath::source_engine::units_to_kilometers(hu);
+
+    static_assert(cm == 25.4, "constexpr hu->cm failed");
+    static_assert(m == 0.254, "constexpr hu->m failed");
+    static_assert(km == 0.000254, "constexpr hu->km failed");
+}
+
 TEST(unit_test_source_engine, ForwardVector)
 {
     const auto forward = omath::source_engine::forward_vector({});

tests/engines/unit_test_unity_engine.cpp

@@ -8,6 +8,126 @@
 #include <print>
 #include <random>
 
+TEST(unit_test_unity_engine, UnitsToCentimeters_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::unity_engine::units_to_centimeters(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::unity_engine::units_to_centimeters(1.0f), 0.01f);
+    EXPECT_FLOAT_EQ(omath::unity_engine::units_to_centimeters(100.0f), 1.0f);
+    EXPECT_FLOAT_EQ(omath::unity_engine::units_to_centimeters(-250.0f), -2.5f);
+}
+
+TEST(unit_test_unity_engine, UnitsToMeters_BasicValues)
+{
+    EXPECT_DOUBLE_EQ(omath::unity_engine::units_to_meters(0.0), 0.0);
+    EXPECT_DOUBLE_EQ(omath::unity_engine::units_to_meters(1.0), 1.0);
+    EXPECT_DOUBLE_EQ(omath::unity_engine::units_to_meters(123.456), 123.456);
+    EXPECT_DOUBLE_EQ(omath::unity_engine::units_to_meters(-42.0), -42.0);
+}
+
+TEST(unit_test_unity_engine, UnitsToKilometers_BasicValues)
+{
+    EXPECT_NEAR(omath::unity_engine::units_to_kilometers(0.0), 0.0, 1e-15);
+    EXPECT_NEAR(omath::unity_engine::units_to_kilometers(1.0), 0.001, 1e-15);
+    EXPECT_NEAR(omath::unity_engine::units_to_kilometers(1000.0), 1.0, 1e-12);
+    EXPECT_NEAR(omath::unity_engine::units_to_kilometers(-2500.0), -2.5, 1e-12);
+}
+
+TEST(unit_test_unity_engine, CentimetersToUnits_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::unity_engine::centimeters_to_units(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::unity_engine::centimeters_to_units(0.01f), 1.0f);
+    EXPECT_FLOAT_EQ(omath::unity_engine::centimeters_to_units(1.0f), 100.0f);
+    EXPECT_FLOAT_EQ(omath::unity_engine::centimeters_to_units(-2.5f), -250.0f);
+}
+
+TEST(unit_test_unity_engine, MetersToUnits_BasicValues)
+{
+    EXPECT_DOUBLE_EQ(omath::unity_engine::meters_to_units(0.0), 0.0);
+    EXPECT_DOUBLE_EQ(omath::unity_engine::meters_to_units(1.0), 1.0);
+    EXPECT_DOUBLE_EQ(omath::unity_engine::meters_to_units(123.456), 123.456);
+    EXPECT_DOUBLE_EQ(omath::unity_engine::meters_to_units(-42.0), -42.0);
+}
+
+TEST(unit_test_unity_engine, KilometersToUnits_BasicValues)
+{
+    EXPECT_NEAR(omath::unity_engine::kilometers_to_units(0.0), 0.0, 1e-12);
+    EXPECT_NEAR(omath::unity_engine::kilometers_to_units(0.001), 1.0, 1e-12);
+    EXPECT_NEAR(omath::unity_engine::kilometers_to_units(1.0), 1000.0, 1e-9);
+    EXPECT_NEAR(omath::unity_engine::kilometers_to_units(-2.5), -2500.0, 1e-9);
+}
+
+TEST(unit_test_unity_engine, RoundTrip_UnitsCentimeters)
+{
+    constexpr float units_f = 12345.678f;
+    constexpr auto cm_f = omath::unity_engine::units_to_centimeters(units_f);
+    constexpr auto units_f_back = omath::unity_engine::centimeters_to_units(cm_f);
+    EXPECT_NEAR(units_f_back, units_f, 1e-3f);
+
+    constexpr double units_d = -987654.321;
+    constexpr auto cm_d = omath::unity_engine::units_to_centimeters(units_d);
+    constexpr auto units_d_back = omath::unity_engine::centimeters_to_units(cm_d);
+    EXPECT_NEAR(units_d_back, units_d, 1e-9);
+}
+
+TEST(unit_test_unity_engine, RoundTrip_UnitsMeters)
+{
+    constexpr float units_f = 5432.125f;
+    constexpr auto m_f = omath::unity_engine::units_to_meters(units_f);
+    constexpr auto units_f_back = omath::unity_engine::meters_to_units(m_f);
+    EXPECT_FLOAT_EQ(units_f_back, units_f);
+
+    constexpr double units_d = -123456.789;
+    constexpr auto m_d = omath::unity_engine::units_to_meters(units_d);
+    constexpr auto units_d_back = omath::unity_engine::meters_to_units(m_d);
+    EXPECT_DOUBLE_EQ(units_d_back, units_d);
+}
+
+TEST(unit_test_unity_engine, RoundTrip_UnitsKilometers)
+{
+    constexpr float units_f = 100000.0f;
+    constexpr auto km_f = omath::unity_engine::units_to_kilometers(units_f);
+    constexpr auto units_f_back = omath::unity_engine::kilometers_to_units(km_f);
+    EXPECT_NEAR(units_f_back, units_f, 1e-2f);
+
+    constexpr double units_d = -7654321.123;
+    constexpr auto km_d = omath::unity_engine::units_to_kilometers(units_d);
+    constexpr auto units_d_back = omath::unity_engine::kilometers_to_units(km_d);
+    EXPECT_NEAR(units_d_back, units_d, 1e-6);
+}
+
+TEST(unit_test_unity_engine, ConversionChainConsistency)
+{
+    constexpr double units = 424242.42;
+
+    constexpr auto cm_direct = omath::unity_engine::units_to_centimeters(units);
+    constexpr auto cm_via_units = units / 100.0;
+    EXPECT_NEAR(cm_direct, cm_via_units, 1e-12);
+
+    constexpr auto km_direct = omath::unity_engine::units_to_kilometers(units);
+    constexpr auto km_via_meters = omath::unity_engine::units_to_meters(units) / 1000.0;
+    EXPECT_NEAR(km_direct, km_via_meters, 1e-12);
+}
+
+TEST(unit_test_unity_engine, SupportsFloatAndDouble)
+{
+    static_assert(std::is_same_v<decltype(omath::unity_engine::units_to_centimeters(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::unity_engine::units_to_centimeters(1.0)), double>);
+    static_assert(std::is_same_v<decltype(omath::unity_engine::meters_to_units(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::unity_engine::kilometers_to_units(1.0)), double>);
+}
+
+TEST(unit_test_unity_engine, ConstexprConversions)
+{
+    constexpr double units = 1000.0;
+    constexpr double cm = omath::unity_engine::units_to_centimeters(units);
+    constexpr double m = omath::unity_engine::units_to_meters(units);
+    constexpr double km = omath::unity_engine::units_to_kilometers(units);
+
+    static_assert(cm == 10.0, "units_to_centimeters constexpr failed");
+    static_assert(m == 1000.0, "units_to_meters constexpr failed");
+    static_assert(km == 1.0, "units_to_kilometers constexpr failed");
+}
+
 TEST(unit_test_unity_engine, ForwardVector)
 {
     const auto forward = omath::unity_engine::forward_vector({});

tests/engines/unit_test_unreal_engine.cpp

@@ -239,3 +239,126 @@ TEST(unit_test_unreal_engine, loook_at_random_z_axis)
     }
     EXPECT_LE(failed_points, 100);
 }
+TEST(unit_test_unreal_engine, UnitsToCentimeters_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::unreal_engine::units_to_centimeters(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::unreal_engine::units_to_centimeters(1.0f), 1.0f);
+    EXPECT_FLOAT_EQ(omath::unreal_engine::units_to_centimeters(250.0f), 250.0f);
+    EXPECT_FLOAT_EQ(omath::unreal_engine::units_to_centimeters(-42.5f), -42.5f);
+}
+
+TEST(unit_test_unreal_engine, UnitsToMeters_BasicValues)
+{
+    EXPECT_NEAR(omath::unreal_engine::units_to_meters(0.0), 0.0, 1e-15);
+    EXPECT_NEAR(omath::unreal_engine::units_to_meters(1.0), 0.01, 1e-15);
+    EXPECT_NEAR(omath::unreal_engine::units_to_meters(100.0), 1.0, 1e-12);
+    EXPECT_NEAR(omath::unreal_engine::units_to_meters(-250.0), -2.5, 1e-12);
+}
+
+TEST(unit_test_unreal_engine, UnitsToKilometers_BasicValues)
+{
+    EXPECT_NEAR(omath::unreal_engine::units_to_kilometers(0.0), 0.0, 1e-18);
+    EXPECT_NEAR(omath::unreal_engine::units_to_kilometers(1.0), 0.00001, 1e-18);
+    EXPECT_NEAR(omath::unreal_engine::units_to_kilometers(100000.0), 1.0, 1e-12);
+    EXPECT_NEAR(omath::unreal_engine::units_to_kilometers(-250000.0), -2.5, 1e-12);
+}
+
+TEST(unit_test_unreal_engine, CentimetersToUnits_BasicValues)
+{
+    EXPECT_FLOAT_EQ(omath::unreal_engine::centimeters_to_units(0.0f), 0.0f);
+    EXPECT_FLOAT_EQ(omath::unreal_engine::centimeters_to_units(1.0f), 1.0f);
+    EXPECT_FLOAT_EQ(omath::unreal_engine::centimeters_to_units(250.0f), 250.0f);
+    EXPECT_FLOAT_EQ(omath::unreal_engine::centimeters_to_units(-42.5f), -42.5f);
+}
+
+TEST(unit_test_unreal_engine, MetersToUnits_BasicValues)
+{
+    EXPECT_NEAR(omath::unreal_engine::meters_to_units(0.0), 0.0, 1e-12);
+    EXPECT_NEAR(omath::unreal_engine::meters_to_units(0.01), 1.0, 1e-12);
+    EXPECT_NEAR(omath::unreal_engine::meters_to_units(1.0), 100.0, 1e-9);
+    EXPECT_NEAR(omath::unreal_engine::meters_to_units(-2.5), -250.0, 1e-9);
+}
+
+TEST(unit_test_unreal_engine, KilometersToUnits_BasicValues)
+{
+    EXPECT_NEAR(omath::unreal_engine::kilometers_to_units(0.0), 0.0, 1e-9);
+    EXPECT_NEAR(omath::unreal_engine::kilometers_to_units(0.00001), 1.0, 1e-9);
+    EXPECT_NEAR(omath::unreal_engine::kilometers_to_units(1.0), 100000.0, 1e-6);
+    EXPECT_NEAR(omath::unreal_engine::kilometers_to_units(-2.5), -250000.0, 1e-3);
+}
+
+TEST(unit_test_unreal_engine, RoundTrip_UnitsCentimeters)
+{
+    constexpr float units_f = 12345.678f;
+    constexpr auto cm_f = omath::unreal_engine::units_to_centimeters(units_f);
+    constexpr auto units_f_back = omath::unreal_engine::centimeters_to_units(cm_f);
+    EXPECT_FLOAT_EQ(units_f_back, units_f);
+
+    constexpr double units_d = -987654.321;
+    constexpr auto cm_d = omath::unreal_engine::units_to_centimeters(units_d);
+    constexpr auto units_d_back = omath::unreal_engine::centimeters_to_units(cm_d);
+    EXPECT_DOUBLE_EQ(units_d_back, units_d);
+}
+
+TEST(unit_test_unreal_engine, RoundTrip_UnitsMeters)
+{
+    constexpr float units_f = 5432.125f;
+    constexpr auto m_f = omath::unreal_engine::units_to_meters(units_f);
+    constexpr auto units_f_back = omath::unreal_engine::meters_to_units(m_f);
+    EXPECT_NEAR(units_f_back, units_f, 1e-3f);
+
+    constexpr double units_d = -123456.789;
+    constexpr auto m_d = omath::unreal_engine::units_to_meters(units_d);
+    constexpr auto units_d_back = omath::unreal_engine::meters_to_units(m_d);
+    EXPECT_NEAR(units_d_back, units_d, 1e-9);
+}
+
+TEST(unit_test_unreal_engine, RoundTrip_UnitsKilometers)
+{
+    constexpr float units_f = 100000.0f;
+    constexpr auto km_f = omath::unreal_engine::units_to_kilometers(units_f);
+    constexpr auto units_f_back = omath::unreal_engine::kilometers_to_units(km_f);
+    EXPECT_NEAR(units_f_back, units_f, 1e-2f);
+
+    constexpr double units_d = -7654321.123;
+    constexpr auto km_d = omath::unreal_engine::units_to_kilometers(units_d);
+    constexpr auto units_d_back = omath::unreal_engine::kilometers_to_units(km_d);
+    EXPECT_NEAR(units_d_back, units_d, 1e-6);
+}
+
+TEST(unit_test_unreal_engine, ConversionChainConsistency)
+{
+    constexpr double units = 424242.42;
+
+    constexpr auto cm_direct = omath::unreal_engine::units_to_centimeters(units);
+    constexpr auto cm_expected = units; // 1 uu == 1 cm
+    EXPECT_NEAR(cm_direct, cm_expected, 1e-12);
+
+    constexpr auto m_direct = omath::unreal_engine::units_to_meters(units);
+    constexpr auto m_via_cm = cm_direct / 100.0;
+    EXPECT_NEAR(m_direct, m_via_cm, 1e-12);
+
+    constexpr auto km_direct = omath::unreal_engine::units_to_kilometers(units);
+    constexpr auto km_via_m = m_direct / 1000.0;
+    EXPECT_NEAR(km_direct, km_via_m, 1e-15);
+}
+
+TEST(unit_test_unreal_engine, SupportsFloatAndDouble)
+{
+    static_assert(std::is_same_v<decltype(omath::unreal_engine::units_to_centimeters(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::unreal_engine::units_to_centimeters(1.0)), double>);
+    static_assert(std::is_same_v<decltype(omath::unreal_engine::meters_to_units(1.0f)), float>);
+    static_assert(std::is_same_v<decltype(omath::unreal_engine::kilometers_to_units(1.0)), double>);
+}
+
+TEST(unit_test_unreal_engine, ConstexprConversions)
+{
+    constexpr double units = 100000.0;
+    constexpr double cm = omath::unreal_engine::units_to_centimeters(units);
+    constexpr double m = omath::unreal_engine::units_to_meters(units);
+    constexpr double km = omath::unreal_engine::units_to_kilometers(units);
+
+    static_assert(cm == 100000.0, "units_to_centimeters constexpr failed");
+    static_assert(m == 1000.0, "units_to_meters constexpr failed");
+    static_assert(km == 1.0, "units_to_kilometers constexpr failed");
+}

vcpkg.json

@@ -27,10 +27,11 @@
       ]
     },
     "examples": {
-      "description": "Build benchmarks",
+      "description": "Build examples",
       "dependencies": [
         "glfw3",
-        "glew"
+        "glew",
+        "opengl"
       ]
     },
     "imgui": {