www.pudn.com > ATimeToKill.rar > object.h

#ifndef __OBJECT_H 
#define __OBJECT_H 
 
#include "tree.h" 
#include "vector.h" 
#include "camera.h" 
 
/* 
	OBJECT.H 
 
  	The CObject class 
 
	OpenGL Game Programming 
	Author: Kevin Hawkins 
	Date: 3/29/2001 
	Description: The CObject class is derived from CNode and 
			   represents an object in the game world. 
 
*/ 
 
class CObject : public CNode 
{ 
protected: 
 
     // perform basic physics on the object 
     virtual void OnAnimate(scalar_t deltaTime)  
     { 
          position += velocity * deltaTime; 
          velocity += acceleration * deltaTime; 
     } 
 
     // draw the object given the camera position 
     virtual void OnDraw(CCamera *camera) {}  
 
     // collide with other objects 
     virtual void OnCollision(CObject *collisionObject) {} 
 
     // perform collision and other preparations for this object 
     virtual void OnPrepare()  
     { 
          ProcessCollisions(FindRoot());     // perform collisions starting with 
                                             // root world object 
     } 
 
public: 
     CVector position;        // object position 
     CVector velocity;        // velocity of object 
     CVector acceleration;    // acceleration 
     scalar_t size;           // size of bounding sphere (radius) 
 
     bool isDead; 
 
     CObject() { isDead = false; } 
     ~CObject() {} 
 
     virtual void Load() {} 
     virtual void Unload() {} 
 
     // draw object 
     void Draw(CCamera *camera)  
     { 
          // push modelview matrix on stack 
          glPushMatrix(); 
               OnDraw(camera);          // draw this object 
               if (HasChild())          // draw children 
                    ((CObject*)childNode)->Draw(camera); 
          glPopMatrix(); 
 
          // draw siblings 
          if (HasParent() && !IsLastChild()) 
               ((CObject*)nextNode)->Draw(camera); 
     } 
 
     // animate object 
     void Animate(scalar_t deltaTime)  
     { 
          OnAnimate(deltaTime);         // animate this object 
      
          // animate children 
          if (HasChild()) 
               ((CObject*)childNode)->Animate(deltaTime); 
 
          // animate siblings 
          if (HasParent() && !IsLastChild()) 
               ((CObject*)nextNode)->Animate(deltaTime); 
 
          if (isDead) 
               delete this; 
     } 
 
     // perform collision detection 
     void ProcessCollisions(CObject *obj)  
     { 
          // if this object's bounding sphere collides with obj's sphere 
          // and obj is not this object 
          if (((obj->position - position).Length() <= (obj->size + size)) && 
               (obj != ((CObject*)this))) 
          { 
               OnCollision(obj);        // perform this object's collision with obj 
 
               // test child collisions with obj 
               if (HasChild()) 
                    ((CObject*)childNode)->ProcessCollisions(obj); 
 
               // test sibling collisions with obj 
               if (HasParent() && !IsLastChild()) 
                    ((CObject*)nextNode)->ProcessCollisions(obj); 
          } 
 
          // if obj has children, check collisions with these children 
          if (obj->HasChild()) 
               ProcessCollisions((CObject*)(obj->childNode)); 
 
          // if obj has siblings, check collisions with these siblings 
          if (obj->HasParent() && !obj->IsLastChild()) 
               ProcessCollisions((CObject*)(obj->nextNode)); 
     } 
 
     // prepare object 
     void Prepare() 
     { 
          OnPrepare();                            // prepare this object 
 
          if (HasChild())                         // prepare children 
               ((CObject*)childNode)->Prepare(); 
 
          if (HasParent() && !IsLastChild())      // prepare siblings 
               ((CObject*)nextNode)->Prepare(); 
     } 
 
     // find root object of cyclic linked list tree 
     CObject *FindRoot() 
     { 
          // if this object has a parent node, return the root of the parent node 
          if (parentNode) 
               return ((CObject*)parentNode)->FindRoot(); 
 
          return this; 
     } 
}; 
 
 
#endif