www.pudn.com > ATimeToKill.rar > Particles.cpp

/**************************************************************************** 
 Particles.cpp 
  
 Author   :   Dave Astle 
 Date     :   2/1/2001 
 
 Written for OpenGL Game Programming 
*****************************************************************************/ 
#include "Particles.h" 
 
 
/***************************************************************************** 
 CParticleSystem::Constructor 
  
 Store initialization values and set defaults. 
*****************************************************************************/ 
CParticleSystem::CParticleSystem(int maxParticles, CVector origin) 
{ 
  m_maxParticles = maxParticles; 
  m_origin = origin; 
  m_particleList = NULL; 
} // end CParticleSystem::Constructor 
 
 
/***************************************************************************** 
 CParticleSystem::Emit() 
  
 Creates the number of new particles specified by the parameter, using 
 the general particle system values with some random element. Note that 
 only initial values will be randomized. Final values will not. This may 
 be changed in the future. 
*****************************************************************************/ 
int CParticleSystem::Emit(int numParticles) 
{ 
  // create numParticles new particles (if there's room) 
  while (numParticles && (m_numParticles < m_maxParticles)) 
  { 
    // initialize the current particle and increase the count 
    InitializeParticle(m_numParticles++); 
    --numParticles; 
  } 
  return numParticles; 
} // end CParticleSystem::Emit 
 
 
/***************************************************************************** 
 CParticleSystem::InitializeSystem() 
  
 Allocate memory for the maximum number of particles in the system 
*****************************************************************************/ 
void CParticleSystem::InitializeSystem() 
{ 
  // if this is just a reset, free the memory 
  if (m_particleList) 
  { 
    delete[] m_particleList; 
    m_particleList = NULL; 
  } 
 
  // allocate the maximum number of particles 
  m_particleList = new particle_t[m_maxParticles]; 
 
  // reset the number of particles and accumulated time 
  m_numParticles = 0; 
  m_accumulatedTime = 0.0f; 
} // end CParticleSystem::InitializeSystem 
 
 
/***************************************************************************** 
 CParticleSystem::KillSystem() 
  
 Tells the emitter to stop emitting. If the parameter is true, all live 
 particles are killed as well.  Otherwise, they are allowed to die off on 
 their own. 
*****************************************************************************/ 
void CParticleSystem::KillSystem() 
{ 
  if (m_particleList) 
  { 
    delete[] m_particleList; 
    m_particleList = NULL; 
  } 
 
  m_numParticles = 0; 
} // end CParticleSystem::KillSystem