// This could be local to main(), if you want, but that limits your
//     flexibility (e.g., to dynamicall change the # of threads)
Thread *worker[ numberOfThreads ];

// This needs to be visible to the display function and the worker threads
Barrier *displayBarrier;

// changes to main routine for multi-threaded ray tracer
int main(int argc, char** argv)
{
  .
  .
  .

  // Initialize synchronization mechanisms (+1 because of the display thread)
  displayBarrier = new Barrier( numberOfThreads+1 );

  // Create computation threads
  for (int i=0;i < numberOfThreads ;i++)
  {
	  worker[i] = new Thread( i );
	  worker[i]->Create( WorkerLoop );
  }
	
  .
  .
  .


  // Start execution of the OpenGL program
  glutMainLoop();
  return 0;
}