//===========================================================================//
// File:	gyro.hpp                                                            //
// Project: BattleTech           Brick: Mech subsystems                       //
// Contents: Gyroscope -- the eye/body stabilisation subsystem               //
//---------------------------------------------------------------------------//
// Copyright (C) 1995, Virtual World Entertainment, Inc.                     //
// All Rights reserved worldwide                                             //
// This unpublished sourcecode is PROPRIETARY and CONFIDENTIAL               //
//===========================================================================//

#if !defined(GYRO_HPP)
#	define GYRO_HPP

#	if !defined(POWERSUB_HPP)
#		include <powersub.hpp>
#	endif

//#####################    Forward Class Declarations  #######################
	class Mech;

//###########################################################################
//###################   Gyroscope Model Resource   #########################
//###########################################################################

	//
	// One per-damage-type response row: how hard a hit of that type kicks
	// the four gyro channels.
	//
	struct Gyroscope__DamageResponse
	{
		Scalar	trans;
		Scalar	pitchRoll;
		Scalar	yaw;
		Scalar	vibration;
	};

	struct Gyroscope__SubsystemResource:
		public PowerWatcher::SubsystemResource
	{
		Scalar		reservedF4;
		Scalar		exageration;
		Scalar		maxAnimationNoise;
		Scalar		minAnimationNoise;
		Scalar		rotationPerSecond;
		Scalar		percentageOnNormal;
		Scalar		percentageOnDestruction;
		Scalar		percentageOnDegradation;
		Scalar		percentageOnFailure;
		Vector3D	springConstant;
		Vector3D	dampingConstant;
		Vector3D	posSpring;
		Vector3D	negSpring;
		Vector3D	rotationSpringConstant;
		Vector3D	rotationDampingConstant;
		Vector3D	rotationPosSpring;
		Vector3D	rotationNegSpring;
		char		eyeJoint[32];
		char		mechJoint[32];
		Scalar		collisionDamageMultiplier;
		Scalar		ballisticDamageMultiplier;
		Scalar		explosiveDamageMultiplier;
		Scalar		laserDamageMultiplier;
		Scalar		energyDamageMultiplier;

		//
		// The five response quads follow the multipliers in the stream
		// (record size 0x21C -- binary-verified layout).
		//
		Gyroscope__DamageResponse	collisionDamageResponse;
		Gyroscope__DamageResponse	ballisticDamageResponse;
		Gyroscope__DamageResponse	explosiveDamageResponse;
		Gyroscope__DamageResponse	laserDamageResponse;
		Gyroscope__DamageResponse	energyDamageResponse;
	};

//###########################################################################
//##############################   Gyroscope   #############################
//###########################################################################
//
// The gyro drives the cockpit eye joint (view stabilisation) and the body
// lean.  The tuning constants are read from the resource; the eye/body
// dynamics state (springs, forces, velocities, work matrices) is advanced by
// the per-frame GyroscopeSimulation and held in dynamicsState until that
// (staged) method is reconstructed with the named fields.
//
	class Gyroscope:
		public PowerWatcher
	{
	public:
		static Derivation ClassDerivations;
		static SharedData DefaultData;

		typedef void
			(Gyroscope::*Performance)(Scalar time_slice);
		void
			SetPerformance(Performance performance)
			{
				Check(this);
				activePerformance = (Simulation::Performance)performance;
			}

		static Logical
			TestClass(Mech &);
		Logical
			TestInstance() const;
		void
			ResetToInitialState();
		void
			GyroscopeSimulation(Scalar time_slice);

		//
		// The two integrators (called by the sim) and the two joint writes
		// (called by the MECH master performance tail, after the gait --
		// NOT by the sim; binary @0x4aaf74/83).
		//
		void
			IntegrateEyeJoint(Scalar time_slice);
		void
			IntegrateBody(Scalar time_slice);
		void
			WriteEyeJoint();
		void
			WriteMechJoint();

		//
		// The hit-bounce feeds.  ApplyDamageResponse is the damage hub's
		// fan-out (every non-collision hit shakes the cockpit); the three
		// primitive kicks are also fed directly by the collision CRUNCH.
		//
		void
			ApplyDamageResponse(const Damage &damage);
		void
			ApplyDamageImpulse(Scalar x, Scalar y, Scalar z, Scalar magnitude);
		void
			ApplyDamageTorque(Scalar x, Scalar y, Scalar z, Scalar magnitude);
		void
			ApplyVerticalImpulse(Scalar pitch, Scalar magnitude);

	public:
		typedef Gyroscope__SubsystemResource SubsystemResource;

		Gyroscope(
			Mech						*owner,
			int							subsystem_ID,
			SubsystemResource			*subsystem_resource,
			SharedData					&shared_data = DefaultData
		);
		~Gyroscope();

	protected:
		Scalar		exageration;
		Scalar		maxAnimationNoise;
		Scalar		minAnimationNoise;
		Scalar		rotationPerSecond;
		Scalar		percentageOnNormal;
		Scalar		percentageOnDestruction;
		Scalar		percentageOnDegradation;
		Scalar		percentageOnFailure;
		Vector3D	springConstant;
		Vector3D	dampingConstant;
		Vector3D	posSpring;
		Vector3D	negSpring;
		Vector3D	rotationSpringConstant;
		Vector3D	rotationDampingConstant;
		Vector3D	rotationPosSpring;
		Vector3D	rotationNegSpring;
		Scalar		damageMultiplier[5];
		Gyroscope__DamageResponse
					damageResponse[5];

		//
		// The eye TRANSLATION spring state (the steady eye offset + hit
		// bounce) and the body ROTATION spring state (the hull tip).  The
		// clamps are COPIES of the spring pairs, taken at ctor time (the
		// body pair scaled by 2).
		//
		Vector3D	eyePosition, eyeVelocity, eyeForce, eyeWork;
		Vector3D	eyeClampUpper, eyeClampLower;
		Vector3D	bodyOrientation, bodyVelocity, bodyForce, bodyWork;
		Vector3D	bodyClampUpper, bodyClampLower;

		//
		// Sway (the animation-noise wander the sim slews between the
		// powered/impaired percentages) and the placement scratch the
		// damage fan-out rotates hit directions through.
		//
		Scalar		swayAngle, swayBias, swayVelocity;
		int			swayActive;
		Vector3D	placeRot, placePos;
		Scalar		placeQuat[4];
		Scalar		workMatrix[12];
		Scalar		spare0;
		Scalar		*externalPitchPtr;	// -> the torso twist (yaw-only hit
										// frame); self-points at spare0
										// until a torso binds it
		Vector3D	vibrationDirection;	// the fixed up axis
		Joint		*eyeJointNode;
		Joint		*mechJointNode;
	};

#endif