Merge pull request #91 from orange-cpp/feature/frostbite_engine

Defines constants for Frostbite engine

include/omath/engines/frostbite_engine/camera.hpp

@@ -0,0 +1,13 @@
+//
+// Created by Vlad on 3/22/2025.
+//
+
+#pragma once
+#include "omath/engines/frostbite_engine/constants.hpp"
+#include "omath/projection/camera.hpp"
+#include "traits/camera_trait.hpp"
+
+namespace omath::frostbite_engine
+{
+    using Camera =  projection::Camera<Mat4X4, ViewAngles, CameraTrait>;
+} // namespace omath::unity_engine

include/omath/engines/frostbite_engine/constants.hpp

@@ -0,0 +1,25 @@
+//
+// Created by Vlad on 10/21/2025.
+//
+
+#pragma once
+#include "omath/linear_algebra/mat.hpp"
+#include "omath/linear_algebra/vector3.hpp"
+#include <omath/trigonometry/angle.hpp>
+#include <omath/trigonometry/view_angles.hpp>
+
+namespace omath::frostbite_engine
+{
+    constexpr Vector3<float> k_abs_up = {0, 1, 0};
+    constexpr Vector3<float> k_abs_right = {1, 0, 0};
+    constexpr Vector3<float> k_abs_forward = {0, 0, 1};
+
+    using Mat4X4 = Mat<4, 4, float, MatStoreType::ROW_MAJOR>;
+    using Mat3X3 = Mat<4, 4, float, MatStoreType::ROW_MAJOR>;
+    using Mat1X3 = Mat<1, 3, float, MatStoreType::ROW_MAJOR>;
+    using PitchAngle = Angle<float, -90.f, 90.f, AngleFlags::Clamped>;
+    using YawAngle = Angle<float, -180.f, 180.f, AngleFlags::Normalized>;
+    using RollAngle = Angle<float, -180.f, 180.f, AngleFlags::Normalized>;
+
+    using ViewAngles = omath::ViewAngles<PitchAngle, YawAngle, RollAngle>;
+} // namespace omath::frostbite_engine

include/omath/engines/frostbite_engine/formulas.hpp

@@ -0,0 +1,26 @@
+//
+// Created by Vlad on 3/22/2025.
+//
+
+#pragma once
+#include "omath/engines/frostbite_engine/constants.hpp"
+
+namespace omath::frostbite_engine
+{
+    [[nodiscard]]
+    Vector3<float> forward_vector(const ViewAngles& angles) noexcept;
+
+    [[nodiscard]]
+    Vector3<float> right_vector(const ViewAngles& angles) noexcept;
+
+    [[nodiscard]]
+    Vector3<float> up_vector(const ViewAngles& angles) noexcept;
+
+    [[nodiscard]] Mat4X4 calc_view_matrix(const ViewAngles& angles, const Vector3<float>& cam_origin) noexcept;
+
+    [[nodiscard]]
+    Mat4X4 rotation_matrix(const ViewAngles& angles) noexcept;
+
+    [[nodiscard]]
+    Mat4X4 calc_perspective_projection_matrix(float field_of_view, float aspect_ratio, float near, float far) noexcept;
+} // namespace omath::unity_engine

include/omath/engines/frostbite_engine/traits/camera_trait.hpp

@@ -0,0 +1,24 @@
+//
+// Created by Vlad on 8/10/2025.
+//
+
+#pragma once
+#include "omath/engines/frostbite_engine/formulas.hpp"
+#include "omath/projection/camera.hpp"
+
+namespace omath::frostbite_engine
+{
+    class CameraTrait final
+    {
+    public:
+        [[nodiscard]]
+        static ViewAngles calc_look_at_angle(const Vector3<float>& cam_origin, const Vector3<float>& look_at) noexcept;
+
+        [[nodiscard]]
+        static Mat4X4 calc_view_matrix(const ViewAngles& angles, const Vector3<float>& cam_origin) noexcept;
+        [[nodiscard]]
+        static Mat4X4 calc_projection_matrix(const projection::FieldOfView& fov, const projection::ViewPort& view_port,
+                                             float near, float far) noexcept;
+    };
+
+} // namespace omath::unreal_engine

include/omath/engines/frostbite_engine/traits/pred_engine_trait.hpp

@@ -0,0 +1,76 @@
+//
+// Created by Vlad on 8/6/2025.
+//
+#pragma once
+#include "omath/engines/frostbite_engine/formulas.hpp"
+#include "omath/projectile_prediction/projectile.hpp"
+#include "omath/projectile_prediction/target.hpp"
+#include <optional>
+
+namespace omath::frostbite_engine
+{
+    class PredEngineTrait final
+    {
+    public:
+        constexpr static Vector3<float> predict_projectile_position(const projectile_prediction::Projectile& projectile,
+                                                                    const float pitch, const float yaw,
+                                                                    const float time, const float gravity) noexcept
+        {
+            auto current_pos = projectile.m_origin
+                               + forward_vector({PitchAngle::from_degrees(-pitch), YawAngle::from_degrees(yaw),
+                                                 RollAngle::from_degrees(0)})
+                                         * projectile.m_launch_speed * time;
+            current_pos.y -= (gravity * projectile.m_gravity_scale) * (time * time) * 0.5f;
+
+            return current_pos;
+        }
+        [[nodiscard]]
+        static constexpr Vector3<float> predict_target_position(const projectile_prediction::Target& target,
+                                                                const float time, const float gravity) noexcept
+        {
+            auto predicted = target.m_origin + target.m_velocity * time;
+
+            if (target.m_is_airborne)
+                predicted.y -= gravity * (time * time) * 0.5f;
+
+            return predicted;
+        }
+        [[nodiscard]]
+        static float calc_vector_2d_distance(const Vector3<float>& delta) noexcept
+        {
+            return std::sqrt(delta.x * delta.x + delta.z * delta.z);
+        }
+
+        [[nodiscard]]
+        constexpr static float get_vector_height_coordinate(const Vector3<float>& vec) noexcept
+        {
+            return vec.y;
+        }
+
+        [[nodiscard]]
+        static Vector3<float> calc_viewpoint_from_angles(const projectile_prediction::Projectile& projectile,
+                                                         Vector3<float> predicted_target_position,
+                                                         const std::optional<float> projectile_pitch) noexcept
+        {
+            const auto delta2d = calc_vector_2d_distance(predicted_target_position - projectile.m_origin);
+            const auto height = delta2d * std::tan(angles::degrees_to_radians(projectile_pitch.value()));
+
+            return {predicted_target_position.x, predicted_target_position.y + height, projectile.m_origin.z};
+        }
+        // Due to specification of maybe_calculate_projectile_launch_pitch_angle, pitch angle must be:
+        // 89 look up, -89 look down
+        [[nodiscard]]
+        static float calc_direct_pitch_angle(const Vector3<float>& origin, const Vector3<float>& view_to) noexcept
+        {
+            const auto direction = (view_to - origin).normalized();
+            return angles::radians_to_degrees(std::asin(direction.y));
+        }
+        [[nodiscard]]
+        static float calc_direct_yaw_angle(const Vector3<float>& origin, const Vector3<float>& view_to) noexcept
+        {
+            const auto direction = (view_to - origin).normalized();
+
+            return angles::radians_to_degrees(std::atan2(direction.x, direction.z));
+        };
+    };
+} // namespace omath::unity_engine

source/engines/frostbite_engine/formulas.cpp

@@ -0,0 +1,42 @@
+//
+// Created by Vlad on 3/22/2025.
+//
+#include "omath/engines/frostbite_engine/formulas.hpp"
+
+namespace omath::frostbite_engine
+{
+    Vector3<float> forward_vector(const ViewAngles& angles) noexcept
+    {
+        const auto vec = rotation_matrix(angles) * mat_column_from_vector(k_abs_forward);
+
+        return {vec.at(0, 0), vec.at(1, 0), vec.at(2, 0)};
+    }
+    Vector3<float> right_vector(const ViewAngles& angles) noexcept
+    {
+        const auto vec = rotation_matrix(angles) * mat_column_from_vector(k_abs_right);
+
+        return {vec.at(0, 0), vec.at(1, 0), vec.at(2, 0)};
+    }
+    Vector3<float> up_vector(const ViewAngles& angles) noexcept
+    {
+        const auto vec = rotation_matrix(angles) * mat_column_from_vector(k_abs_up);
+
+        return {vec.at(0, 0), vec.at(1, 0), vec.at(2, 0)};
+    }
+    Mat4X4 calc_view_matrix(const ViewAngles& angles, const Vector3<float>& cam_origin) noexcept
+    {
+        return mat_camera_view<float, MatStoreType::ROW_MAJOR>(forward_vector(angles), right_vector(angles),
+                                                               up_vector(angles), cam_origin);
+    }
+    Mat4X4 rotation_matrix(const ViewAngles& angles) noexcept
+    {
+        return mat_rotation_axis_z<float, MatStoreType::ROW_MAJOR>(angles.roll)
+               * mat_rotation_axis_y<float, MatStoreType::ROW_MAJOR>(angles.yaw)
+               * mat_rotation_axis_x<float, MatStoreType::ROW_MAJOR>(angles.pitch);
+    }
+    Mat4X4 calc_perspective_projection_matrix(const float field_of_view, const float aspect_ratio, const float near,
+                                              const float far) noexcept
+    {
+        return mat_perspective_left_handed(field_of_view, aspect_ratio, near, far);
+    }
+} // namespace omath::unity_engine

source/engines/frostbite_engine/traits/camera_trait.cpp

@@ -0,0 +1,26 @@
+//
+// Created by Vlad on 8/11/2025.
+//
+#include "omath/engines/frostbite_engine/traits/camera_trait.hpp"
+
+namespace omath::frostbite_engine
+{
+
+    ViewAngles CameraTrait::calc_look_at_angle(const Vector3<float>& cam_origin, const Vector3<float>& look_at) noexcept
+    {
+        const auto direction = (look_at - cam_origin).normalized();
+
+        return {PitchAngle::from_radians(-std::asin(direction.y)),
+                YawAngle::from_radians(std::atan2(direction.x, direction.z)), RollAngle::from_radians(0.f)};
+    }
+    Mat4X4 CameraTrait::calc_view_matrix(const ViewAngles& angles, const Vector3<float>& cam_origin) noexcept
+    {
+        return frostbite_engine::calc_view_matrix(angles, cam_origin);
+    }
+    Mat4X4 CameraTrait::calc_projection_matrix(const projection::FieldOfView& fov,
+                                               const projection::ViewPort& view_port, const float near,
+                                               const float far) noexcept
+    {
+        return calc_perspective_projection_matrix(fov.as_degrees(), view_port.aspect_ratio(), near, far);
+    }
+} // namespace omath::unity_engine

tests/engines/unit_test_frostbite_engine.cpp

@@ -0,0 +1,236 @@
+//
+// Created by Vlad on 10/23/2025.
+//
+#include <gtest/gtest.h>
+#include <omath/engines/frostbite_engine/camera.hpp>
+#include <omath/engines/frostbite_engine/constants.hpp>
+#include <omath/engines/frostbite_engine/formulas.hpp>
+#include <print>
+#include <random>
+
+TEST(unit_test_frostbite_engine, ForwardVector)
+{
+    const auto forward = omath::frostbite_engine::forward_vector({});
+
+    EXPECT_EQ(forward, omath::frostbite_engine::k_abs_forward);
+}
+
+TEST(unit_test_frostbite_engine, ForwardVectorRotationYaw)
+{
+    omath::frostbite_engine::ViewAngles angles;
+
+    angles.yaw = omath::frostbite_engine::YawAngle::from_degrees(90.f);
+
+    const auto forward = omath::frostbite_engine::forward_vector(angles);
+    EXPECT_NEAR(forward.x, omath::frostbite_engine::k_abs_right.x, 0.00001f);
+    EXPECT_NEAR(forward.y, omath::frostbite_engine::k_abs_right.y, 0.00001f);
+    EXPECT_NEAR(forward.z, omath::frostbite_engine::k_abs_right.z, 0.00001f);
+}
+
+TEST(unit_test_frostbite_engine, ForwardVectorRotationPitch)
+{
+    omath::frostbite_engine::ViewAngles angles;
+
+    angles.pitch = omath::frostbite_engine::PitchAngle::from_degrees(-90.f);
+
+    const auto forward = omath::frostbite_engine::forward_vector(angles);
+    EXPECT_NEAR(forward.x, omath::frostbite_engine::k_abs_up.x, 0.00001f);
+    EXPECT_NEAR(forward.y, omath::frostbite_engine::k_abs_up.y, 0.00001f);
+    EXPECT_NEAR(forward.z, omath::frostbite_engine::k_abs_up.z, 0.00001f);
+}
+
+TEST(unit_test_frostbite_engine, ForwardVectorRotationRoll)
+{
+    omath::frostbite_engine::ViewAngles angles;
+
+    angles.roll = omath::frostbite_engine::RollAngle::from_degrees(-90.f);
+
+    const auto forward = omath::frostbite_engine::up_vector(angles);
+    EXPECT_NEAR(forward.x, omath::frostbite_engine::k_abs_right.x, 0.00001f);
+    EXPECT_NEAR(forward.y, omath::frostbite_engine::k_abs_right.y, 0.00001f);
+    EXPECT_NEAR(forward.z, omath::frostbite_engine::k_abs_right.z, 0.00001f);
+}
+
+TEST(unit_test_frostbite_engine, RightVector)
+{
+    const auto right = omath::frostbite_engine::right_vector({});
+
+    EXPECT_EQ(right, omath::frostbite_engine::k_abs_right);
+}
+
+TEST(unit_test_frostbite_engine, UpVector)
+{
+    const auto up = omath::frostbite_engine::up_vector({});
+    EXPECT_EQ(up, omath::frostbite_engine::k_abs_up);
+}
+
+TEST(unit_test_frostbite_engine, ProjectTargetMovedFromCamera)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(60.f);
+    const auto cam = omath::frostbite_engine::Camera({0, 0, 0}, {}, {1280.f, 720.f}, fov, 0.01f, 1000.f);
+
+    for (float distance = 0.02f; distance < 100.f; distance += 0.01f)
+    {
+        const auto projected = cam.world_to_screen({0, 0, distance});
+
+        EXPECT_TRUE(projected.has_value());
+
+        if (!projected.has_value())
+            continue;
+
+        EXPECT_NEAR(projected->x, 640, 0.00001f);
+        EXPECT_NEAR(projected->y, 360, 0.00001f);
+    }
+}
+TEST(unit_test_frostbite_engine, Project)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(60.f);
+
+    const auto cam = omath::frostbite_engine::Camera({0, 0, 0}, {}, {1280.f, 720.f}, fov, 0.03f, 1000.f);
+    const auto proj = cam.world_to_screen<omath::frostbite_engine::Camera::ScreenStart::BOTTOM_LEFT_CORNER>({10.f, 3, 10.f});
+
+    EXPECT_NEAR(proj->x, 1263.538, 0.001f);
+    EXPECT_NEAR(proj->y, 547.061f, 0.001f);
+}
+
+TEST(unit_test_frostbite_engine, CameraSetAndGetFov)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    auto cam = omath::frostbite_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.01f, 1000.f);
+
+    EXPECT_EQ(cam.get_field_of_view().as_degrees(), 90.f);
+    cam.set_field_of_view(omath::projection::FieldOfView::from_degrees(50.f));
+
+    EXPECT_EQ(cam.get_field_of_view().as_degrees(), 50.f);
+}
+
+TEST(unit_test_frostbite_engine, CameraSetAndGetOrigin)
+{
+    auto cam = omath::frostbite_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, {}, 0.01f, 1000.f);
+
+    EXPECT_EQ(cam.get_origin(), omath::Vector3<float>{});
+    cam.set_field_of_view(omath::projection::FieldOfView::from_degrees(50.f));
+
+    EXPECT_EQ(cam.get_field_of_view().as_degrees(), 50.f);
+}
+TEST(unit_test_frostbite_engine, loook_at_random_all_axis)
+{
+    std::mt19937 gen(std::random_device{}()); // Seed with a non-deterministic source
+    std::uniform_real_distribution<float> dist(-1000.f, 1000.f);
+
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    auto cam = omath::frostbite_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.001f, 10000.f);
+
+    std::size_t failed_points = 0;
+
+    for (int i = 0; i < 1000; i++)
+    {
+        const auto position_to_look = omath::Vector3<float>{dist(gen), dist(gen), dist(gen)};
+
+        if (cam.get_origin().distance_to(position_to_look) < 10)
+            continue;
+
+        cam.look_at(position_to_look);
+
+        auto projected_pos = cam.world_to_view_port(position_to_look);
+
+        EXPECT_TRUE(projected_pos.has_value());
+
+        if (!projected_pos)
+            continue;
+
+        if (std::abs(projected_pos->x - 0.f) >= 0.0001f || std::abs(projected_pos->y - 0.f) >= 0.0001f)
+            failed_points++;
+    }
+    EXPECT_LE(failed_points, 100);
+}
+
+TEST(unit_test_frostbite_engine, loook_at_random_x_axis)
+{
+    std::mt19937 gen(std::random_device{}()); // Seed with a non-deterministic source
+    std::uniform_real_distribution<float> dist(-1000.f, 1000.f);
+
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    auto cam = omath::frostbite_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.001f, 10000.f);
+
+    std::size_t failed_points = 0;
+    for (int i = 0; i < 1000; i++)
+    {
+        const auto position_to_look = omath::Vector3<float>{dist(gen), 0.f, 0.f};
+        if (cam.get_origin().distance_to(position_to_look) < 10)
+            continue;
+
+        cam.look_at(position_to_look);
+
+        auto projected_pos = cam.world_to_view_port(position_to_look);
+
+        EXPECT_TRUE(projected_pos.has_value());
+
+        if (!projected_pos)
+            continue;
+
+        if (std::abs(projected_pos->x - 0.f) >= 0.001f || std::abs(projected_pos->y - 0.f) >= 0.001f)
+            failed_points++;
+    }
+    EXPECT_LE(failed_points, 100);
+}
+
+TEST(unit_test_frostbite_engine, loook_at_random_y_axis)
+{
+    std::mt19937 gen(std::random_device{}()); // Seed with a non-deterministic source
+    std::uniform_real_distribution<float> dist(-1000.f, 1000.f);
+
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    auto cam = omath::frostbite_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.001f, 10000.f);
+
+    std::size_t failed_points = 0;
+    for (int i = 0; i < 1000; i++)
+    {
+        const auto position_to_look = omath::Vector3<float>{0.f, dist(gen), 0.f};
+        if (cam.get_origin().distance_to(position_to_look) < 10)
+            continue;
+
+        cam.look_at(position_to_look);
+
+        auto projected_pos = cam.world_to_view_port(position_to_look);
+
+        EXPECT_TRUE(projected_pos.has_value());
+
+        if (!projected_pos)
+            continue;
+
+        if (std::abs(projected_pos->x - 0.f) >= 0.01f || std::abs(projected_pos->y - 0.f) >= 0.01f)
+            failed_points++;
+    }
+    EXPECT_LE(failed_points, 100);
+}
+
+TEST(unit_test_frostbite_engine, loook_at_random_z_axis)
+{
+    std::mt19937 gen(std::random_device{}()); // Seed with a non-deterministic source
+    std::uniform_real_distribution<float> dist(-1000.f, 1000.f);
+
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    auto cam = omath::frostbite_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.001f, 10000.f);
+
+    std::size_t failed_points = 0;
+    for (int i = 0; i < 1000; i++)
+    {
+        const auto position_to_look = omath::Vector3<float>{0.f, 0.f, dist(gen)};
+        if (cam.get_origin().distance_to(position_to_look) < 10)
+            continue;
+
+        cam.look_at(position_to_look);
+
+        auto projected_pos = cam.world_to_view_port(position_to_look);
+
+        EXPECT_TRUE(projected_pos.has_value());
+
+        if (!projected_pos)
+            continue;
+
+        if (std::abs(projected_pos->x - 0.f) >= 0.01f || std::abs(projected_pos->y - 0.f) >= 0.01f)
+            failed_points++;
+    }
+    EXPECT_LE(failed_points, 100);
+}