Function DoRainEffect

Descent3/weather.cpp:47–169

Makes droplets appear on the windshield, plus makes rain fall in the distance

// Makes droplets appear on the windshield, plus makes rain fall in the distance
void DoRainEffect() {
  // See how many droplets to create on the windshield
  // This is dependant on how fast the player is moving forward
  int randval = 1 + ((1.0 - Weather.rain_intensity_scalar) * MAX_RAIN_INTENSITY);

  if (randval < 20)
    randval = 20;

  vector vel = Viewer_object->mtype.phys_info.velocity;
  float mag = vm_GetMagnitudeFast(&vel);
  vel /= mag;

  float scalar = vm_DotProduct(&vel, &Viewer_object->orient.fvec);

  vector upvec = {0, 1.0, 0};

  scalar *= (1 + (mag / 100));

  randval -= scalar * 10;

  if (randval < 2)
    randval = 2;
  else if (randval > 80)
    randval = 80;

  if ((upvec * Viewer_object->orient.uvec) < 0)
    randval = 8000; // Make sure rain does fall upwards

  if (Viewer_object->type == OBJ_PLAYER && OBJECT_OUTSIDE(Viewer_object) && (ps_rand() % randval) == 0) {
    // Put some droplets on the windshield
    vector pos = {0, 0, 0};

    pos.x = ((ps_rand() % 1000) - 500) / 250.0;
    pos.y = ((ps_rand() % 1000) - 500) / 350.0;
    pos.z = 3.0;

    int visnum = VisEffectCreate(VIS_FIREBALL, RAINDROP_INDEX, Viewer_object->roomnum, &pos);
    if (visnum >= 0) {
      vis_effect *vis = &VisEffects[visnum];
      float life = .4 + ((ps_rand() % 500) / 1000.0);
      vis->lifeleft = life;
      vis->lifetime = life;
      vis->size = .01 + ((ps_rand() % 500) / 3000.0);

      if (vis->size > .05) {
        Sound_system.Play2dSound(SOUND_RAINDROP);
      }

      vis->flags |= VF_WINDSHIELD_EFFECT;
    }
  }

  // Create some rain in the distance

  if (OBJECT_OUTSIDE(Viewer_object)) {
    int num = 20 + (ps_rand() % 15);
    angvec angs;
    int i;