physenv.h

本程序描述的是一个三维织物动感模拟系统。计算机生成真实感服装被列入计算机图形学亟需解决的三大问题之一。

#if !defined(AFX_PhysEnv_H__3DC11AC3_95FB_11D2_9D83_00105A124906__INCLUDED_)
#define AFX_PhysEnv_H__3DC11AC3_95FB_11D2_9D83_00105A124906__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000
// PhysEnv.h : header file
//
#include "MathDefs.h"

#define EPSILON  0.00001f				// ERROR TERM
#define DEFAULT_DAMPING		0.002f

enum tCollisionTypes
{
	NOT_COLLIDING,
	PENETRATING,
	COLLIDING
};

enum tIntegratorTypes
{
	EULER_INTEGRATOR,
	MIDPOINT_INTEGRATOR,
	RK4_INTEGRATOR
};


// CLASSIFY THE SPRINGS SO I CAN HANDLE THEM SEPARATELY
enum tSpringTypes
{
	MANUAL_SPRING,
	STRUCTURAL_SPRING,
	SHEAR_SPRING,
	BEND_SPRING
};

// TYPE FOR A PLANE THAT THE SYSTEM WILL COLLIDE WITH
struct tCollisionPlane
{
	tVector normal;			// inward pointing
    float	d;				// ax + by + cz + d = 0
};

// TYPE FOR A PHYSICAL PARTICLE IN THE SYSTEM
struct tParticle
{
	tVector pos;		// Position of Particle
    tVector v;			// Velocity of Particle
	tVector f;			// Force Acting on Particle
	float	oneOverM;	// 1 / Mass of Particle
};

// TYPE FOR CONTACTS THAT ARE FOUND DURING SIM
struct tContact
{
	int		particle;	// Particle Index
    tVector normal;		// Normal of Collision plane
};

// TYPE FOR COLLISION SPHERES IN SYSTEM
struct tCollisionSphere
{
	float	radius;		// RADIUS OF SPHERE
    tVector pos;		// POSITION OF SPHERE
};

// TYPE FOR SPRINGS IN SYSTEM
struct tSpring
{
	int		p1,p2;		// PARTICLE INDEX FOR ENDS
	float	restLen;	// LENGTH OF SPRING AT REST
	float	Ks;			// SPRING CONSTANT
	float	Kd;			// SPRING DAMPING
	int		type;		// SPRING TYPE - USED FOR SPECIAL FEATURES
};

class CPhysEnv
{
// Construction
public:
	CPhysEnv();
	void RenderWorld();
	void SetWorldParticles(tTexturedVertex *coords,int particleCnt);
	void ResetWorld();
	void Simulate(float DeltaTime,BOOL running);
	void ApplyUserForce(tVector *force);
	void SetMouseForce(int deltaX,int deltaY, tVector *localX, tVector *localY);
	void GetNearestPoint(int x, int y);
	void AddSpring();
	void AddSpring(int v1, int v2,float Ksh,float Ksd, int type);
	void SetWorldProperties();
	void SetVertexProperties();
	void FreeSystem();
	void LoadData(FILE *fp);
	void SaveData(FILE *fp);
	void	AddCollisionSphere();
	BOOL				m_UseGravity;			// SHOULD GRAVITY BE ADDED IN
	BOOL				m_UseDamping;			// SHOULD DAMPING BE ON
	BOOL				m_UserForceActive;		// WHEN USER FORCE IS APPLIED
	BOOL				m_DrawSprings;			// DRAW THE SPRING LINES
	BOOL				m_DrawVertices;			// DRAW VERTICES
	BOOL				m_MouseForceActive;		// MOUSE DRAG FORCE
	BOOL				m_CollisionActive;		// COLLISION SPHERES ACTIVE
	BOOL				m_CollisionRootFinding;	// AM I SEARCHING FOR A COLLISION
	BOOL				m_DrawStructural;		// DRAW STRUCTURAL CLOTH SPRINGS
	BOOL				m_DrawShear;			// DRAW SHEAR CLOTH SPRINGS
	BOOL				m_DrawBend;				// DRAW BEND CLOTH SPRINGS
	int					m_IntegratorType;

// Attributes
private:
	float				m_WorldSizeX,m_WorldSizeY,m_WorldSizeZ;
	tVector				m_Gravity;				// GRAVITY FORCE VECTOR
	tVector				m_UserForce;			// USER FORCE VECTOR
	float				m_UserForceMag;			// MAGNITUDE OF USER FORCE
	float				m_Kd;					// DAMPING FACTOR
	float				m_Kr;					// COEFFICIENT OF RESTITUTION
	float				m_Ksh;					// HOOK'S SPRING CONSTANT
	float				m_Ksd;					// SPRING DAMPING
	float				m_MouseForceKs;			// MOUSE SPRING COEFFICIENT
	tCollisionPlane		*m_CollisionPlane;		// LIST OF COLLISION PLANES
	int					m_CollisionPlaneCnt;			
	tContact			*m_Contact;				// LIST OF POSSIBLE COLLISIONS
	int					m_ContactCnt;			// COLLISION COUNT
	tParticle			*m_ParticleSys[3];		// LIST OF PHYSICAL PARTICLES
	tParticle			*m_CurrentSys,*m_TargetSys;
	tParticle			*m_TempSys[5];			// SETUP FOR TEMP PARTICLES USED WHILE INTEGRATING
	int					m_ParticleCnt;
	tSpring				*m_Spring;				// VALID SPRINGS IN SYSTEM
	int					m_SpringCnt;		
	int					m_Pick[2];				// INDEX COUNTERS FOR SELECTING
	tVector				m_MouseDragPos[2];		// POSITION OF DRAGGED MOUSE VECTOR
	tCollisionSphere	*m_Sphere;
	int					m_SphereCnt;
// Operations
private:
	inline void	IntegrateSysOverTime(tParticle *initial,tParticle *source, tParticle *target, float deltaTime);
	void	RK4Integrate( float DeltaTime);
	void	MidPointIntegrate( float DeltaTime);
	void	EulerIntegrate( float DeltaTime);
	void	ComputeForces( tParticle	*system );
	int		CheckForCollisions( tParticle	*system );
	void	ResolveCollisions( tParticle	*system );
	void	CompareBuffer(int size, float *buffer,float x, float y);

// Implementation
public:
	virtual ~CPhysEnv();

};

/////////////////////////////////////////////////////////////////////////////

//{{AFX_INSERT_LOCATION}}
// Microsoft Visual C++ will insert additional declarations immediately before the previous line.

#endif // !defined(AFX_PhysEnv_H__3DC11AC3_95FB_11D2_9D83_00105A124906__INCLUDED_)