ich würde das so lösen:
erst gucks du wie gewohn, ob der spieler in reichweite ist, wenn ja nimmst du 2 punkte die relativ zur tür sind und bestimmst welcher näher ist...:

z.b.:
Code:

---

action door
{
   var standart_rotation[3];
   vec_set(standart_rotation,my.pan);
   while(1)
   {
      if(vec_dist(my.x,player.x)<300)
      {
         vec_set(temp,vector(0,20,0));
         vec_rotate(temp,standart_rotation);
         vec_add(temp,my.x);

         vec_set(target,vector(0,-20,0));//abuse target-vector
         vec_rotate(target,standart_rotation);
         vec_add(target,my.x);
         if(vec_dist(temp,player.x)<vec_dist(target,player.x))
         {
            while(abs(my.pan-standart_rotation.pan)<90)
            {
               my.pan+=5*time_step;
               wait(1);
            }
         }
         else
         {
            while(abs(my.pan-standart_rotation.pan)<90)
            {
               my.pan-=5*time_step;
               wait(1);
            }
         }
         while(vec_dist(my.x,player.x)<400){wait(1);}
         if(my.pan>standart_rotation.pan)
         {
            while(abs(my.pan-standart_rotation.pan)<2)
            {
               my.pan-=5*time_step;
               wait(1);
            }
         }
         else
         {
            while(abs(my.pan-standart_rotation.pan)<2)
            {
               my.pan+=5*time_step;
               wait(1);
            }
         }
         my.pan = standart_rotation.pan;
      }
      wait(1);
   }
}

---

PS: wouldn't it be easy when that forum would support highlighting...?