added AABB check

include/omath/3d_primitives/aabb.hpp

@@ -0,0 +1,16 @@
+//
+// Created by Vladislav on 24.03.2026.
+//
+
+#pragma once
+#include "omath/linear_algebra/vector3.hpp"
+
+namespace omath::primitives
+{
+    template<class Type>
+    struct Aabb final
+    {
+        Vector3<Type> min;
+        Vector3<Type> max;
+    };
+} // namespace omath::primitives

include/omath/projection/camera.hpp

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include "omath/3d_primitives/aabb.hpp"
 #include "omath/linear_algebra/mat.hpp"
 #include "omath/linear_algebra/triangle.hpp"
 #include "omath/linear_algebra/vector3.hpp"
@@ -308,6 +309,63 @@ namespace omath::projection
             return false;
         }
 
+        [[nodiscard]] bool is_aabb_culled_by_frustum(const primitives::Aabb<float>& aabb) const noexcept
+        {
+            const auto& m = get_view_projection_matrix();
+
+            // Gribb-Hartmann: extract 6 frustum planes from the view-projection matrix.
+            // Each plane is (a, b, c, d) such that ax + by + cz + d >= 0 means inside.
+            // For a 4x4 matrix with rows r0..r3:
+            //   Left   = r3 + r0
+            //   Right  = r3 - r0
+            //   Bottom = r3 + r1
+            //   Top    = r3 - r1
+            //   Near   = r3 + r2  ([-1,1]) or r2 ([0,1])
+            //   Far    = r3 - r2
+            struct Plane final
+            {
+                float a, b, c, d;
+            };
+
+            const auto extract_plane = [&m](const int sign, const int row) -> Plane
+            {
+                return {
+                        m.at(3, 0) + static_cast<float>(sign) * m.at(row, 0),
+                        m.at(3, 1) + static_cast<float>(sign) * m.at(row, 1),
+                        m.at(3, 2) + static_cast<float>(sign) * m.at(row, 2),
+                        m.at(3, 3) + static_cast<float>(sign) * m.at(row, 3),
+                };
+            };
+
+            std::array<Plane, 6> planes = {
+                    extract_plane(1, 0), // left
+                    extract_plane(-1, 0), // right
+                    extract_plane(1, 1), // bottom
+                    extract_plane(-1, 1), // top
+                    extract_plane(-1, 2), // far
+            };
+
+            // Near plane depends on NDC depth range
+            if constexpr (depth_range == NDCDepthRange::ZERO_TO_ONE)
+                planes[5] = {m.at(2, 0), m.at(2, 1), m.at(2, 2), m.at(2, 3)};
+            else
+                planes[5] = extract_plane(1, 2);
+
+            // For each plane, find the AABB corner most in the direction of the plane normal
+            // (the "positive vertex"). If it's outside, the entire AABB is outside.
+            for (const auto& [a, b, c, d] : planes)
+            {
+                const float px = a >= 0.f ? aabb.max.x : aabb.min.x;
+                const float py = b >= 0.f ? aabb.max.y : aabb.min.y;
+                const float pz = c >= 0.f ? aabb.max.z : aabb.min.z;
+
+                if (a * px + b * py + c * pz + d < 0.f)
+                    return true;
+            }
+
+            return false;
+        }
+
         [[nodiscard]] std::expected<Vector3<float>, Error>
         world_to_view_port(const Vector3<float>& world_position,
                            const ViewPortClipping& clipping = ViewPortClipping::AUTO) const noexcept

tests/general/unit_test_projection.cpp

@@ -4,6 +4,8 @@
 #include "omath/engines/unity_engine/camera.hpp"
 #include <complex>
 #include <gtest/gtest.h>
+#include <omath/3d_primitives/aabb.hpp>
+#include <omath/engines/opengl_engine/camera.hpp>
 #include <omath/engines/source_engine/camera.hpp>
 #include <omath/projection/camera.hpp>
 #include <print>
@@ -217,3 +219,295 @@ TEST(UnitTestProjection, ScreenToWorldBottomLeftCorner)
         EXPECT_NEAR(screen_cords->y, initial_screen_cords.y, 0.001f);
     }
 }
+
+TEST(UnitTestProjection, AabbInsideFrustumNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Small box directly in front of camera (Source Engine: +X forward, +Y left, +Z up)
+    const omath::primitives::Aabb<float> aabb{{90.f, -1.f, -1.f}, {110.f, 1.f, 1.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbBehindCameraCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box entirely behind the camera
+    const omath::primitives::Aabb<float> aabb{{-200.f, -1.f, -1.f}, {-100.f, 1.f, 1.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbBeyondFarPlaneCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box beyond far plane (1000)
+    const omath::primitives::Aabb<float> aabb{{1500.f, -1.f, -1.f}, {2000.f, 1.f, 1.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbFarLeftCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box far to the side, outside the frustum
+    const omath::primitives::Aabb<float> aabb{{90.f, 4000.f, -1.f}, {110.f, 5000.f, 1.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbFarRightCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box far to the other side, outside the frustum
+    const omath::primitives::Aabb<float> aabb{{90.f, -5000.f, -1.f}, {110.f, -4000.f, 1.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbAboveCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box far above the frustum
+    const omath::primitives::Aabb<float> aabb{{90.f, -1.f, 5000.f}, {110.f, 1.f, 6000.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbPartiallyInsideNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Large box that straddles the frustum boundary — partially inside
+    const omath::primitives::Aabb<float> aabb{{50.f, -5000.f, -5000.f}, {500.f, 5000.f, 5000.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbStraddlesNearPlaneNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box that straddles the near plane — partially in front
+    const omath::primitives::Aabb<float> aabb{{-5.f, -1.f, -1.f}, {5.f, 1.f, 1.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbStraddlesFarPlaneNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box that straddles the far plane
+    const omath::primitives::Aabb<float> aabb{{900.f, -1.f, -1.f}, {1100.f, 1.f, 1.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbCulledUnityEngine)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(60.f);
+    const auto cam = omath::unity_engine::Camera({0, 0, 0}, {}, {1280.f, 720.f}, fov, 0.03f, 1000.f);
+
+    // Box in front — not culled
+    const omath::primitives::Aabb<float> inside{{-1.f, -1.f, 50.f}, {1.f, 1.f, 100.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(inside));
+
+    // Box behind — culled
+    const omath::primitives::Aabb<float> behind{{-1.f, -1.f, -200.f}, {1.f, 1.f, -100.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(behind));
+}
+
+TEST(UnitTestProjection, AabbBelowCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box far below the frustum (Source Engine: +Z up)
+    const omath::primitives::Aabb<float> aabb{{90.f, -1.f, -6000.f}, {110.f, 1.f, -5000.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbEnclosesCameraNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Huge box that fully encloses the camera
+    const omath::primitives::Aabb<float> aabb{{-500.f, -500.f, -500.f}, {500.f, 500.f, 500.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbExactlyAtNearPlaneNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box starting exactly at the near plane distance
+    const omath::primitives::Aabb<float> aabb{{0.01f, -1.f, -1.f}, {10.f, 1.f, 1.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbExactlyAtFarPlaneNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Box ending exactly at the far plane distance
+    const omath::primitives::Aabb<float> aabb{{990.f, -1.f, -1.f}, {1000.f, 1.f, 1.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbNarrowFovCulledAtEdge)
+{
+    // Narrow FOV — box that would be visible at 90 is culled at 30
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(30.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    const omath::primitives::Aabb<float> aabb{{100.f, 200.f, -1.f}, {110.f, 210.f, 1.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbWideFovNotCulledAtEdge)
+{
+    // Wide FOV — same box is visible
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(120.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    const omath::primitives::Aabb<float> aabb{{100.f, 200.f, -1.f}, {110.f, 210.f, 1.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbCameraOffOrigin)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({500.f, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f},
+                                                  fov, 0.01f, 1000.f);
+
+    // Box in front of shifted camera
+    const omath::primitives::Aabb<float> in_front{{600.f, -1.f, -1.f}, {700.f, 1.f, 1.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(in_front));
+
+    // Box behind shifted camera
+    const omath::primitives::Aabb<float> behind{{0.f, -1.f, -1.f}, {100.f, 1.f, 1.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(behind));
+}
+
+TEST(UnitTestProjection, AabbShortFarPlaneCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    // Very short far plane
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 50.f);
+
+    // Box at distance 100 — beyond the 50-unit far plane
+    const omath::primitives::Aabb<float> aabb{{90.f, -1.f, -1.f}, {110.f, 1.f, 1.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+
+    // Box at distance 30 — within range
+    const omath::primitives::Aabb<float> near_box{{25.f, -1.f, -1.f}, {35.f, 1.f, 1.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(near_box));
+}
+
+TEST(UnitTestProjection, AabbPointSizedInsideNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::source_engine::Camera({0, 0, 0}, omath::source_engine::ViewAngles{}, {1920.f, 1080.f}, fov,
+                                                  0.01f, 1000.f);
+
+    // Degenerate zero-volume AABB (a point) inside the frustum
+    const omath::primitives::Aabb<float> aabb{{100.f, 0.f, 0.f}, {100.f, 0.f, 0.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbOpenGlEngineInsideNotCulled)
+{
+    // OpenGL: COLUMN_MAJOR, NEGATIVE_ONE_TO_ONE, inverted_z, forward = -Z
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::opengl_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.01f, 1000.f);
+
+    // Box in front of camera (OpenGL: -Z forward)
+    const omath::primitives::Aabb<float> aabb{{-1.f, -1.f, -110.f}, {1.f, 1.f, -90.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbOpenGlEngineBehindCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::opengl_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.01f, 1000.f);
+
+    // Box behind (OpenGL: +Z is behind the camera)
+    const omath::primitives::Aabb<float> aabb{{-1.f, -1.f, 100.f}, {1.f, 1.f, 200.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbOpenGlEngineBeyondFarCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::opengl_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.01f, 1000.f);
+
+    // Box beyond far plane along -Z
+    const omath::primitives::Aabb<float> aabb{{-1.f, -1.f, -2000.f}, {1.f, 1.f, -1500.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbOpenGlEngineSideCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(90.f);
+    const auto cam = omath::opengl_engine::Camera({0, 0, 0}, {}, {1920.f, 1080.f}, fov, 0.01f, 1000.f);
+
+    // Box far to the right (OpenGL: +X right)
+    const omath::primitives::Aabb<float> aabb{{4000.f, -1.f, -110.f}, {5000.f, 1.f, -90.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbUnityEngineBeyondFarCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(60.f);
+    const auto cam = omath::unity_engine::Camera({0, 0, 0}, {}, {1280.f, 720.f}, fov, 0.03f, 500.f);
+
+    // Box beyond 500-unit far plane (Unity: +Z forward)
+    const omath::primitives::Aabb<float> aabb{{-1.f, -1.f, 600.f}, {1.f, 1.f, 700.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbUnityEngineSideCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(60.f);
+    const auto cam = omath::unity_engine::Camera({0, 0, 0}, {}, {1280.f, 720.f}, fov, 0.03f, 1000.f);
+
+    // Box far above (Unity: +Y up)
+    const omath::primitives::Aabb<float> aabb{{-1.f, 5000.f, 50.f}, {1.f, 6000.f, 100.f}};
+    EXPECT_TRUE(cam.is_aabb_culled_by_frustum(aabb));
+}
+
+TEST(UnitTestProjection, AabbUnityEngineStraddlesNearNotCulled)
+{
+    constexpr auto fov = omath::projection::FieldOfView::from_degrees(60.f);
+    const auto cam = omath::unity_engine::Camera({0, 0, 0}, {}, {1280.f, 720.f}, fov, 0.03f, 1000.f);
+
+    // Box straddles near plane (Unity: +Z forward)
+    const omath::primitives::Aabb<float> aabb{{-1.f, -1.f, -5.f}, {1.f, 1.f, 5.f}};
+    EXPECT_FALSE(cam.is_aabb_culled_by_frustum(aabb));
+}