Return to Main Page

Potions

Slow-fall

  /* Potion's effect is to reduce gravity on the imbiber to 50%.
  Also reduces movement speed by 50%, keeping jump distance about
  the same.  Only supported for player-character imbiber.
  */
 BEGIN_SCRIPT(LoGravPotion,TimedPotion)
 METHODS:
  METHOD void PotionEffect(object imbiber, boolean start)
  {
     if(!Object.InheritsFrom(imbiber,Object.Named("Avatar")))
        return;
     if(start)
     {
        vector vel;

        // Arrest downward velocity by 50%.  If you'd been at 50%
        // gravity all along, you'd actually only be at 30% less
        // velocity at the same depth (a factory of 1/root(2)).
        // This will then tend to encourage use of the potion in
        // mid-fall, which sounds like fun. -TJS
        Physics.GetVelocity(imbiber,vel);
        if(vel.z<0) vel.z/=2;
        Physics.SetVelocity(imbiber,vel);

        DrkInv.AddSpeedControl("LoGrav",0.5,1.0);
        Physics.SetGravity(imbiber,0.50);
     }
     else
     {
        Physics.SetGravity(imbiber,1.00);
        DrkInv.RemoveSpeedControl("LoGrav");
     }
  }
 END_SCRIPT(LoGravPotion)

Movement

Setting Velocity

This is what causes drinking slow-fall potions to free you from being stuck.

 STDMETHOD(SetVelocity)(object obj, const vector ref vel)
 {
  // Setting velocities from scripts wants to be initially clear from the
  // effects of friction, so we break all contacts.  
  cPhysModel *pModel = g_PhysModels.GetActive(obj);
  if (pModel)
  {
     for (int i=0; i<pModel->NumSubModels(); i++)
     {
        pModel->DestroyAllTerrainContacts(i);
        DestroyAllObjectContacts(obj, i, pModel);
     }
  }
  PhysSetVelocity(obj, (mxs_vector*)&vel);
  return S_OK;
 }

Calling DestroyAllTerrainContacts also calls another method that makes you fall off any ropes.

Mission-specific

Mission 6 Key Location

The mission source code basically takes a random number (and RNG seed is based on system uptime in miliseconds): Code (MISS6.SCR):

 #define KEYPATHS 9
 [...]
 SetData("PathNumber",Data.RandInt(1,KEYPATHS)); //which key we're using.
 [...]
 SetupLocation();
 //setup the location, if we are the starting
 //point.  This allows all sorts of wholesome
 //linky goodness.

There is also a game config cheat parameter to fix the key location to a specific one.