ADD: Camera mode

src/scene/camera/camera_rig.h

@@ -0,0 +1,124 @@
+#pragma once
+
+#include <core/world.h>
+
+#include <glm/gtc/quaternion.hpp>
+
+#include <cstdint>
+#include <memory>
+#include <string>
+
+class Camera;
+class InputSystem;
+class SceneManager;
+
+enum class CameraMode : uint8_t
+{
+    Free = 0,
+    Orbit = 1,
+    Follow = 2,
+    Chase = 3,
+    Fixed = 4
+};
+
+enum class CameraTargetType : uint8_t
+{
+    None = 0,
+    WorldPoint = 1,
+    MeshInstance = 2,
+    GLTFInstance = 3
+};
+
+struct CameraTarget
+{
+    CameraTargetType type{CameraTargetType::None};
+    std::string name{};
+    WorldVec3 world_point{0.0, 0.0, 0.0};
+};
+
+struct FreeCameraSettings
+{
+    float move_speed{1.8f};      // world units / second
+    float look_sensitivity{0.0020f};
+    float roll_speed{1.0f};      // radians / second
+};
+
+struct OrbitCameraSettings
+{
+    CameraTarget target{};
+    double distance{10.0};
+    float yaw{0.0f};             // radians
+    float pitch{0.0f};           // radians
+    float look_sensitivity{0.0020f};
+};
+
+struct FollowCameraSettings
+{
+    CameraTarget target{};
+    glm::vec3 position_offset_local{0.0f, 2.0f, 6.0f};
+    glm::quat rotation_offset{1.0f, 0.0f, 0.0f, 0.0f};
+};
+
+struct ChaseCameraSettings
+{
+    CameraTarget target{};
+    glm::vec3 position_offset_local{0.0f, 2.0f, 6.0f};
+    glm::quat rotation_offset{1.0f, 0.0f, 0.0f, 0.0f};
+    float position_lag{8.0f};    // smoothing rate (1/sec), higher = snappier
+    float rotation_lag{10.0f};   // smoothing rate (1/sec)
+};
+
+struct FixedCameraSettings
+{
+};
+
+class CameraRig
+{
+public:
+    CameraRig();
+    ~CameraRig();
+
+    CameraRig(const CameraRig &) = delete;
+    CameraRig &operator=(const CameraRig &) = delete;
+
+    void init(SceneManager &scene, Camera &camera);
+
+    CameraMode mode() const { return _mode; }
+    void set_mode(CameraMode mode, SceneManager &scene, Camera &camera);
+
+    const char *mode_name() const;
+
+    FreeCameraSettings &free_settings() { return _free; }
+    OrbitCameraSettings &orbit_settings() { return _orbit; }
+    FollowCameraSettings &follow_settings() { return _follow; }
+    ChaseCameraSettings &chase_settings() { return _chase; }
+    FixedCameraSettings &fixed_settings() { return _fixed; }
+
+    const FreeCameraSettings &free_settings() const { return _free; }
+    const OrbitCameraSettings &orbit_settings() const { return _orbit; }
+    const FollowCameraSettings &follow_settings() const { return _follow; }
+    const ChaseCameraSettings &chase_settings() const { return _chase; }
+    const FixedCameraSettings &fixed_settings() const { return _fixed; }
+
+    void process_input(InputSystem &input, bool ui_capture_keyboard, bool ui_capture_mouse);
+    void update(SceneManager &scene, Camera &camera, float dt);
+
+    bool resolve_target(SceneManager &scene,
+                        const CameraTarget &target,
+                        WorldVec3 &out_position_world,
+                        glm::quat &out_rotation) const;
+
+private:
+    void recreate_mode(SceneManager &scene, Camera &camera);
+
+    CameraMode _mode{CameraMode::Free};
+    std::unique_ptr<class ICameraMode> _mode_impl;
+    SceneManager *_scene = nullptr;
+    Camera *_camera = nullptr;
+
+    FreeCameraSettings _free{};
+    OrbitCameraSettings _orbit{};
+    FollowCameraSettings _follow{};
+    ChaseCameraSettings _chase{};
+    FixedCameraSettings _fixed{};
+};