/*****************************************************************************/
/**
 * @file eulerangles.h
 * @author FanHao (hao_fan_bit_ee@163.com)
 * @version 0.0
 * @date 2023-05-06
 *
 * @copyright Copyright(c) 2024 Beijing Institute of Technology.\n
 * Lab of Communication and Network
 *
 ******************************************************************************/

/**
 * @addtogroup LinkLayer
 * @{
 */

/**
 * @addtogroup LinkLayerGeometry
 * @{
 */

/**
 * @defgroup LinkLayerGeometry_EulerAngles
 * @{
 */

#ifndef __EULERANGLES_H
#define __EULERANGLES_H

#define EUL_PI 3.14159265358979323846

#define DEG2RAD(d) ((EUL_PI / 180.0) * (d))
#define RAD2DEG(r) ((180.0 / EUL_PI) * (r))

/**
 * Orientations are represented by 3D double precision Tait-Bryan (Euler) tuples
 * called EulerAngles. The angles are in Z, Y', X" order that is often called
 * intrinsic rotations, they are measured in radians. The default (unrotated)
 * orientation is along the X axis. Conceptually, the Z axis rotation is heading,
 * the Y' axis rotation is descending (negative elevation), the X" axis rotation is bank.
 * For example, positive rotation along the Z axis rotates X into Y (turns left), positive
 * rotation along the Y axis rotates Z into X (leans forward), positive rotation
 * along the X axis rotates Y into Z (leans right).
 */

/**
 * @struct EULERANGLES
 * @brief Structure for standard quaternion
 */
typedef struct
{
	double alpha; // unit rad
	double beta;  // unit rad
	double gamma; // unit rad
} EULERANGLES;

typedef enum
{
	EULERANGLES_NONE = 0,
	EULERANGLES_ZYX = 1,
	EULERANGLES_ZYZ = 2,
	EULERANGLES_XYZ = 3,
} EULERANGLES_TYPE;

extern const EULERANGLES EULERANGLES_ZERO;
extern const EULERANGLES EULERANGLES_NIL;

/** @brief Add two EulerAngles. */
EULERANGLES EulerAngles_Add(EULERANGLES e1, EULERANGLES e2);

/** @brief Subtracts two EulerAngles. */
EULERANGLES EulerAngles_Sub(EULERANGLES e1, EULERANGLES e2);

/** @brief Multiplies EulerAngles by a real number. */
void EulerAngles_ScalarMult(EULERANGLES *e, double f);

/** @brief Multiplies EulerAngles by a real number. */
EULERANGLES EulerAngles_GetScalarMult(EULERANGLES e, double f);

/** @brief Normalize EulerAngles. */
void EulerAngles_Normalize(EULERANGLES *e);

/** @brief Normalize EulerAngles. */
EULERANGLES EulerAngles_GetNormalize(EULERANGLES e);

#endif

/** @} LinkLayerGeometry_EulerAngles */

/** @} LinkLayerGeometry */

/** @} LinkLayer */