/* =========================================================================== Doom 3 BFG Edition GPL Source Code Copyright (C) 1993-2012 id Software LLC, a ZeniMax Media company. This file is part of the Doom 3 BFG Edition GPL Source Code ("Doom 3 BFG Edition Source Code"). Doom 3 BFG Edition Source Code is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. Doom 3 BFG Edition Source Code is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Doom 3 BFG Edition Source Code. If not, see . In addition, the Doom 3 BFG Edition Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 BFG Edition Source Code. If not, please request a copy in writing from id Software at the address below. If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA. =========================================================================== */ #ifndef __PHYSICS_RIGIDBODY_H__ #define __PHYSICS_RIGIDBODY_H__ /* =================================================================================== Rigid body physics Employs an impulse based dynamic simulation which is not very accurate but relatively fast and still reliable due to the continuous collision detection. =================================================================================== */ extern const float RB_VELOCITY_MAX; extern const int RB_VELOCITY_TOTAL_BITS; extern const int RB_VELOCITY_EXPONENT_BITS; extern const int RB_VELOCITY_MANTISSA_BITS; typedef struct rididBodyIState_s { idVec3 position; // position of trace model idMat3 orientation; // orientation of trace model idVec3 linearMomentum; // translational momentum relative to center of mass idVec3 angularMomentum; // rotational momentum relative to center of mass rididBodyIState_s() : position( vec3_zero ), orientation( mat3_identity ), linearMomentum( vec3_zero ), angularMomentum( vec3_zero ) { } } rigidBodyIState_t; typedef struct rigidBodyPState_s { int atRest; // set when simulation is suspended float lastTimeStep; // length of last time step idVec3 localOrigin; // origin relative to master idMat3 localAxis; // axis relative to master idVec6 pushVelocity; // push velocity idVec3 externalForce; // external force relative to center of mass idVec3 externalTorque; // external torque relative to center of mass rigidBodyIState_t i; // state used for integration rigidBodyPState_s() : atRest( true ), lastTimeStep( 0 ), localOrigin( vec3_zero ), localAxis( mat3_identity ), pushVelocity( vec6_zero ), externalForce( vec3_zero ), externalTorque( vec3_zero ) { } } rigidBodyPState_t; class idPhysics_RigidBody : public idPhysics_Base { public: CLASS_PROTOTYPE( idPhysics_RigidBody ); idPhysics_RigidBody(); ~idPhysics_RigidBody(); void Save( idSaveGame *savefile ) const; void Restore( idRestoreGame *savefile ); // initialisation void SetFriction( const float linear, const float angular, const float contact ); void SetBouncyness( const float b ); // same as above but drop to the floor first void DropToFloor(); // no contact determination and contact friction void NoContact(); // enable/disable activation by impact void EnableImpact(); void DisableImpact(); public: // common physics interface void SetClipModel( idClipModel *model, float density, int id = 0, bool freeOld = true ); idClipModel * GetClipModel( int id = 0 ) const; int GetNumClipModels() const; void SetMass( float mass, int id = -1 ); float GetMass( int id = -1 ) const; void SetContents( int contents, int id = -1 ); int GetContents( int id = -1 ) const; const idBounds & GetBounds( int id = -1 ) const; const idBounds & GetAbsBounds( int id = -1 ) const; bool Evaluate( int timeStepMSec, int endTimeMSec ); bool Interpolate( const float fraction ); void ResetInterpolationState( const idVec3 & origin, const idMat3 & axis ); void UpdateTime( int endTimeMSec ); int GetTime() const; void GetImpactInfo( const int id, const idVec3 &point, impactInfo_t *info ) const; void ApplyImpulse( const int id, const idVec3 &point, const idVec3 &impulse ); void AddForce( const int id, const idVec3 &point, const idVec3 &force ); void Activate(); void PutToRest(); bool IsAtRest() const; int GetRestStartTime() const; bool IsPushable() const; void SaveState(); void RestoreState(); void SetOrigin( const idVec3 &newOrigin, int id = -1 ); void SetAxis( const idMat3 &newAxis, int id = -1 ); void Translate( const idVec3 &translation, int id = -1 ); void Rotate( const idRotation &rotation, int id = -1 ); const idVec3 & GetOrigin( int id = 0 ) const; const idMat3 & GetAxis( int id = 0 ) const; void SetLinearVelocity( const idVec3 &newLinearVelocity, int id = 0 ); void SetAngularVelocity( const idVec3 &newAngularVelocity, int id = 0 ); const idVec3 & GetLinearVelocity( int id = 0 ) const; const idVec3 & GetAngularVelocity( int id = 0 ) const; void ClipTranslation( trace_t &results, const idVec3 &translation, const idClipModel *model ) const; void ClipRotation( trace_t &results, const idRotation &rotation, const idClipModel *model ) const; int ClipContents( const idClipModel *model ) const; void DisableClip(); void EnableClip(); void UnlinkClip(); void LinkClip(); bool EvaluateContacts(); void SetPushed( int deltaTime ); const idVec3 & GetPushedLinearVelocity( const int id = 0 ) const; const idVec3 & GetPushedAngularVelocity( const int id = 0 ) const; void SetMaster( idEntity *master, const bool orientated ); void WriteToSnapshot( idBitMsg &msg ) const; void ReadFromSnapshot( const idBitMsg &msg ); private: // state of the rigid body rigidBodyPState_t current; rigidBodyPState_t saved; // states for client interpolation rigidBodyPState_t previous; rigidBodyPState_t next; // rigid body properties float linearFriction; // translational friction float angularFriction; // rotational friction float contactFriction; // friction with contact surfaces float bouncyness; // bouncyness idClipModel * clipModel; // clip model used for collision detection // derived properties float mass; // mass of body float inverseMass; // 1 / mass idVec3 centerOfMass; // center of mass of trace model idMat3 inertiaTensor; // mass distribution idMat3 inverseInertiaTensor; // inverse inertia tensor idODE * integrator; // integrator bool dropToFloor; // true if dropping to the floor and putting to rest bool testSolid; // true if testing for solid when dropping to the floor bool noImpact; // if true do not activate when another object collides bool noContact; // if true do not determine contacts and no contact friction // master bool hasMaster; bool isOrientated; private: friend void RigidBodyDerivatives( const float t, const void *clientData, const float *state, float *derivatives ); void Integrate( const float deltaTime, rigidBodyPState_t &next ); bool CheckForCollisions( const float deltaTime, rigidBodyPState_t &next, trace_t &collision ); bool CollisionImpulse( const trace_t &collision, idVec3 &impulse ); void ContactFriction( float deltaTime ); void DropToFloorAndRest(); bool TestIfAtRest() const; void Rest(); void DebugDraw(); }; #endif /* !__PHYSICS_RIGIDBODY_H__ */