/**************************************************************************/
/*  camera.h                                                              */
/**************************************************************************/
/*                         This file is part of:                          */
/*                             GODOT ENGINE                               */
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/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
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#ifndef CAMERA_H
#define CAMERA_H

#include "scene/3d/spatial.h"
#include "scene/3d/spatial_velocity_tracker.h"
#include "scene/main/viewport.h"
#include "scene/resources/environment.h"

class Camera : public Spatial {
	GDCLASS(Camera, Spatial);

public:
	enum Projection {

		PROJECTION_PERSPECTIVE,
		PROJECTION_ORTHOGONAL,
		PROJECTION_FRUSTUM
	};

	enum KeepAspect {
		KEEP_WIDTH,
		KEEP_HEIGHT
	};

	enum DopplerTracking {
		DOPPLER_TRACKING_DISABLED,
		DOPPLER_TRACKING_IDLE_STEP,
		DOPPLER_TRACKING_PHYSICS_STEP
	};

private:
	bool force_change;
	bool current;

	Viewport *viewport;

	Projection mode;

	float fov;
	float size;
	Vector2 frustum_offset;
	float near, far;
	float v_offset;
	float h_offset;
	KeepAspect keep_aspect;

	RID camera;
	RID scenario_id;

	//String camera_group;

	uint32_t layers;

	Ref<Environment> environment;

	//void _camera_make_current(Node *p_camera);
	friend class Viewport;
	void _update_audio_listener_state();

	DopplerTracking doppler_tracking;
	Ref<SpatialVelocityTracker> velocity_tracker;
	bool affect_lod = true;

	///////////////////////////////////////////////////////
	// INTERPOLATION FUNCTIONS
	void _physics_interpolation_ensure_transform_calculated(bool p_force = false) const;
	void _physics_interpolation_ensure_data_flipped();

	// These can be set by derived Cameras,
	// if they wish to do processing (while still
	// allowing physics interpolation to function).
	bool _desired_process_internal = false;
	bool _desired_physics_process_internal = false;

	mutable struct InterpolationData {
		Transform xform_curr;
		Transform xform_prev;
		Transform xform_interpolated;
		Transform camera_xform_interpolated; // After modification according to camera type.
		uint32_t last_update_physics_tick = 0;
		uint32_t last_update_frame = UINT32_MAX;
	} _interpolation_data;

	void _update_process_mode();

protected:
	// Use from derived classes to set process modes instead of setting directly.
	// This is because physics interpolation may need to request process modes additionally.
	void set_desired_process_modes(bool p_process_internal, bool p_physics_process_internal);

	// Opportunity for derived classes to interpolate extra attributes.
	virtual void physics_interpolation_flip_data() {}

	virtual void _physics_interpolated_changed();
	virtual Transform _get_adjusted_camera_transform(const Transform &p_xform) const;
	///////////////////////////////////////////////////////

	void _update_camera();
	virtual void _request_camera_update();
	void _update_camera_mode();

	void _notification(int p_what);
	virtual void _validate_property(PropertyInfo &p_property) const;

	static void _bind_methods();

public:
	enum {

		NOTIFICATION_BECAME_CURRENT = 50,
		NOTIFICATION_LOST_CURRENT = 51
	};

	void set_perspective(float p_fovy_degrees, float p_z_near, float p_z_far);
	void set_orthogonal(float p_size, float p_z_near, float p_z_far);
	void set_frustum(float p_size, Vector2 p_offset, float p_z_near, float p_z_far);
	void set_projection(Camera::Projection p_mode);

	void make_current();
	void clear_current(bool p_enable_next = true);
	void set_current(bool p_current);
	bool is_current() const;

	RID get_camera() const;

	float get_fov() const;
	float get_size() const;
	float get_zfar() const;
	float get_znear() const;
	Vector2 get_frustum_offset() const;

	Projection get_projection() const;

	void set_fov(float p_fov);
	void set_size(float p_size);
	void set_zfar(float p_zfar);
	void set_znear(float p_znear);
	void set_frustum_offset(Vector2 p_offset);

	Transform get_camera_transform() const;

	virtual Vector3 project_ray_normal(const Point2 &p_pos) const;
	virtual Vector3 project_ray_origin(const Point2 &p_pos) const;
	virtual Vector3 project_local_ray_normal(const Point2 &p_pos) const;
	virtual Point2 unproject_position(const Vector3 &p_pos) const;
	bool is_position_behind(const Vector3 &p_pos) const;
	virtual Vector3 project_position(const Point2 &p_point, float p_z_depth) const;

	Vector<Vector3> get_near_plane_points() const;

	void set_cull_mask(uint32_t p_layers);
	uint32_t get_cull_mask() const;

	void set_cull_mask_bit(int p_layer, bool p_enable);
	bool get_cull_mask_bit(int p_layer) const;

	virtual Vector<Plane> get_frustum() const;

	void set_environment(const Ref<Environment> &p_environment);
	Ref<Environment> get_environment() const;

	void set_keep_aspect_mode(KeepAspect p_aspect);
	KeepAspect get_keep_aspect_mode() const;

	void set_v_offset(float p_offset);
	float get_v_offset() const;

	void set_h_offset(float p_offset);
	float get_h_offset() const;

	void set_doppler_tracking(DopplerTracking p_tracking);
	DopplerTracking get_doppler_tracking() const;

	Vector3 get_doppler_tracked_velocity() const;

	void set_affect_lod(bool p_enable) { affect_lod = p_enable; }
	bool get_affect_lod() const { return affect_lod; }

	Camera();
	~Camera();
};

VARIANT_ENUM_CAST(Camera::Projection);
VARIANT_ENUM_CAST(Camera::KeepAspect);
VARIANT_ENUM_CAST(Camera::DopplerTracking);

class ClippedCamera : public Camera {
	GDCLASS(ClippedCamera, Camera);

public:
	enum ProcessMode {
		CLIP_PROCESS_PHYSICS,
		CLIP_PROCESS_IDLE,
	};

private:
	ProcessMode process_mode;
	RID pyramid_shape;
	float margin;

	float clip_offset = 0;

	uint32_t collision_mask;
	bool clip_to_areas;
	bool clip_to_bodies;

	Set<RID> exclude;

	Vector<Vector3> points;

	///////////////////////////////////////////////////////
	// INTERPOLATION FUNCTIONS
	struct InterpolatedData {
		float clip_offset_curr = 0;
		float clip_offset_prev = 0;
	} _interpolation_data;

protected:
	virtual Transform _get_adjusted_camera_transform(const Transform &p_xform) const;
	virtual void physics_interpolation_flip_data();
	virtual void _physics_interpolated_changed();
	///////////////////////////////////////////////////////

	void _notification(int p_what);
	static void _bind_methods();

public:
	void set_clip_to_areas(bool p_clip);
	bool is_clip_to_areas_enabled() const;

	void set_clip_to_bodies(bool p_clip);
	bool is_clip_to_bodies_enabled() const;

	void set_margin(float p_margin);
	float get_margin() const;

	void set_process_mode(ProcessMode p_mode);
	ProcessMode get_process_mode() const;

	void set_collision_mask(uint32_t p_mask);
	uint32_t get_collision_mask() const;

	void set_collision_mask_bit(int p_bit, bool p_value);
	bool get_collision_mask_bit(int p_bit) const;

	void add_exception_rid(const RID &p_rid);
	void add_exception(const Object *p_object);
	void remove_exception_rid(const RID &p_rid);
	void remove_exception(const Object *p_object);
	void clear_exceptions();

	float get_clip_offset() const;

	ClippedCamera();
	~ClippedCamera();
};

VARIANT_ENUM_CAST(ClippedCamera::ProcessMode);

#endif // CAMERA_H