For my code I use a couple of static variables. But when I search the internet, they seem "evil".

For example: I have a function which will be executed every loop (5ms looptime). to increase the speed I added some static variables to it. Is the way I am doing this bad? Are there simple solutions for it?

Code:

int ProgFormula() {
  static int StartPosition;
  static int DeltaPosition;
  static int LoopTime = 5;
  static int AccelerationLoops;
  static int TotalLoops;
  static int EndOne;
  
  static float VelocityLoop;
  static float VelocityFactor;

  int Setpoint;
  
  if (Iteration == -1) {
    StartPosition = PID.ActualPosition;
    DeltaPosition = abs(SetPosition - StartPosition);
    VelocityLoop = Velocity / (1000 / LoopTime);
    TotalLoops = DeltaPosition / VelocityLoop;
    if (TotalLoops <= (AccelerationLoops * 2)) {
      AccelerationLoops = (TotalLoops / 2);
      VelocityFactor = (VelocityLoop * 0.5 / AccelerationLoops) / 2;
    }
    else {
      AccelerationLoops = 70;

      VelocityFactor = VelocityLoop * 0.5 / AccelerationLoops;
    }
    TotalLoops = DeltaPosition / VelocityLoop + AccelerationLoops;
    EndOne = (VelocityFactor * pow(AccelerationLoops, 2));
  }
  else if (Iteration >= 0 && Iteration <= AccelerationLoops) {
    if (StartPosition < SetPosition) {
      Setpoint = VelocityFactor * pow(Iteration, 2) + StartPosition;
    }
    else {
      Setpoint = -VelocityFactor * pow(Iteration, 2) + StartPosition;
    }
  }
  else if (Iteration > AccelerationLoops && Iteration <= (TotalLoops - AccelerationLoops)) {
    if (StartPosition < SetPosition) {
      Setpoint = VelocityLoop * Iteration - EndOne + StartPosition;
    }
    else {
      Setpoint = -VelocityLoop * Iteration + EndOne + StartPosition;
    }
  }
  else if (Iteration >= (TotalLoops - AccelerationLoops) && Iteration <= TotalLoops) {
    if (StartPosition < SetPosition) {
      Setpoint = -VelocityFactor * pow((TotalLoops - Iteration), 2) + DeltaPosition + StartPosition;
    }
    else {
      Setpoint = VelocityFactor * pow((TotalLoops - Iteration), 2) - DeltaPosition + StartPosition;
    }
  }
  else {
    Setpoint = Setpoint;
  }
  return(Setpoint);
}

Is it better to avoid statics? If so why?

Thanks in advance, Koen