/*************************************************************************/
/*  static_raycaster.h                                                   */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
/*                                                                       */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the       */
/* "Software"), to deal in the Software without restriction, including   */
/* without limitation the rights to use, copy, modify, merge, publish,   */
/* distribute, sublicense, and/or sell copies of the Software, and to    */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions:                                             */
/*                                                                       */
/* The above copyright notice and this permission notice shall be        */
/* included in all copies or substantial portions of the Software.       */
/*                                                                       */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
/*************************************************************************/

#ifndef STATIC_RAYCASTER_H
#define STATIC_RAYCASTER_H

#include "core/object/ref_counted.h"

#if !defined(__aligned)

#if defined(_WIN32) && defined(_MSC_VER)
#define __aligned(...) __declspec(align(__VA_ARGS__))
#else
#define __aligned(...) __attribute__((aligned(__VA_ARGS__)))
#endif

#endif

class StaticRaycaster : public RefCounted {
	GDCLASS(StaticRaycaster, RefCounted)
protected:
	static StaticRaycaster *(*create_function)();

public:
	// compatible with embree3 rays
	struct __aligned(16) Ray {
		const static unsigned int INVALID_GEOMETRY_ID = ((unsigned int)-1); // from rtcore_common.h

		/*! Default construction does nothing. */
		_FORCE_INLINE_ Ray() :
				geomID(INVALID_GEOMETRY_ID) {}

		/*! Constructs a ray from origin, direction, and ray segment. Near
		 *  has to be smaller than far. */
		_FORCE_INLINE_ Ray(const Vector3 &org,
				const Vector3 &dir,
				float tnear = 0.0f,
				float tfar = INFINITY) :
				org(org),
				tnear(tnear),
				dir(dir),
				time(0.0f),
				tfar(tfar),
				mask(-1),
				u(0.0),
				v(0.0),
				primID(INVALID_GEOMETRY_ID),
				geomID(INVALID_GEOMETRY_ID),
				instID(INVALID_GEOMETRY_ID) {}

		/*! Tests if we hit something. */
		_FORCE_INLINE_ explicit operator bool() const { return geomID != INVALID_GEOMETRY_ID; }

	public:
		Vector3 org; //!< Ray origin + tnear
		float tnear; //!< Start of ray segment
		Vector3 dir; //!< Ray direction + tfar
		float time; //!< Time of this ray for motion blur.
		float tfar; //!< End of ray segment
		unsigned int mask; //!< used to mask out objects during traversal
		unsigned int id; //!< ray ID
		unsigned int flags; //!< ray flags

		Vector3 normal; //!< Not normalized geometry normal
		float u; //!< Barycentric u coordinate of hit
		float v; //!< Barycentric v coordinate of hit
		unsigned int primID; //!< primitive ID
		unsigned int geomID; //!< geometry ID
		unsigned int instID; //!< instance ID
	};

	virtual bool intersect(Ray &p_ray) = 0;
	virtual void intersect(Vector<Ray> &r_rays) = 0;

	virtual void add_mesh(const PackedVector3Array &p_vertices, const PackedInt32Array &p_indices, unsigned int p_id) = 0;
	virtual void commit() = 0;

	virtual void set_mesh_filter(const Set<int> &p_mesh_ids) = 0;
	virtual void clear_mesh_filter() = 0;

	static Ref<StaticRaycaster> create();
};

#endif // STATIC_RAYCASTER_H