[feat]: implement ui layer arch

1 files changed, 65 insertions, 0 deletions

diff --git a/src/scene/scene.cpp b/src/scene/scene.cpp
new file mode 100644
index 0000000..db70a8d
--- /dev/null
+++ b/src/scene/scene.cpp
@@ -0,0 +1,65 @@
+#include "scene.h"
+
+#include <glm/glm.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+#include <algorithm>
+#include <cmath>
+#include <numbers>
+
+namespace Donut
+{
+    Scene::Scene()
+    {
+        // Black-hole camera: large-scale orbital viewer outside the disk.
+        sim_camera.set_camera_mode(CameraMode::Orbital);
+        sim_camera.set_orbital_target(glm::vec3(0.0f));
+        sim_camera.set_orbital_radius(4e11);          // ~31 r_s: outside the 12 r_s disk
+        sim_camera.set_orbital_limits(2.2e11, 1.5e12);
+        sim_camera.set_orbital_speed(0.01f);
+        sim_camera.set_zoom_speed(3e10);
+        sim_camera.set_azimuth(0.0f);
+        sim_camera.set_elevation(1.25f);
+
+        // Scene camera: normal-scale orbital world-builder viewer.
+        scene_camera.set_camera_mode(CameraMode::Orbital);
+        scene_camera.set_orbital_target(glm::vec3(0.0f));
+        scene_camera.set_orbital_radius(15.0);
+        scene_camera.set_orbital_limits(2.0, 200.0);
+        scene_camera.set_orbital_speed(0.01f);
+        scene_camera.set_zoom_speed(2.0);
+        scene_camera.set_azimuth(0.0f);
+        scene_camera.set_elevation((float)std::numbers::pi / 3.0f);
+        scene_camera.update_orbital();
+    }
+
+    auto Scene::reset_sim_camera() -> void
+    {
+        sim_camera.set_camera_mode(CameraMode::Orbital);
+        sim_camera.set_orbital_radius(4e11);
+        sim_camera.set_azimuth(0.0f);
+        sim_camera.set_elevation(1.25f);
+    }
+
+    auto Scene::set_free_fly(bool enabled) -> void
+    {
+        const bool is_fps = sim_camera.get_camera_mode() == CameraMode::FPS;
+        if (enabled == is_fps) return;
+        if (enabled)
+        {
+            // Seed the fly pose from the current orbital framing so the view is continuous.
+            glm::vec3 pos = sim_camera.get_orbital_position();
+            glm::vec3 fwd = glm::normalize(sim_camera.get_orbital_target() - pos);
+            float pitch = glm::degrees(asin(glm::clamp(fwd.y, -1.0f, 1.0f)));
+            float yaw   = glm::degrees(atan2(fwd.z, fwd.x));
+            sim_camera.set_camera_mode(CameraMode::FPS);
+            sim_camera.set_movement_speed(2.0e10f);
+            sim_camera.set_mouse_sensitivity(0.15f);
+            sim_camera.set_position(pos);
+            sim_camera.set_rotation(glm::vec3(pitch, yaw, 0.0f));
+        }
+        else
+        {
+            sim_camera.set_camera_mode(CameraMode::Orbital);  // orbital state was left intact
+        }
+    }
+}