Mine

   1.
                                      if ( seth.value[VAR_AIMPREDICT] ){
   2.
                                              // predict back to last snapshot
   3.
                                              vec3_t dir;
   4.
                                              if( !VectorCompare(  eth.entities[target].origin, vec3_origin ) &&
   5.
                                                      !VectorCompare(  history[target][0].trPos, vec3_origin ))
   6.
                                              {
   7.
                                             
   8.
                                             
   9.
                                                      VectorSubtract( eth.entities[target].origin, history[target][0].trPos, dir );
  10.
                                                      float s = VectorLength( dir ) * seth.value[VAR_AIMPREDICT];
  11.
                                                      if( s < 50.0 ){
  12.
                                                              VectorScale( dir, seth.value[VAR_AIMPREDICT], dir );
  13.
                                                              //VectorNormalize2( dir, dir );
  14.
                                                              VectorAdd( eth.entities[target].head_visible_pt, dir, eth.entities[target].head_visible_pt );
  15.
                                                              VectorNormalize2( dir, dir );
  16.
                                                              printf("Moving %i %.4f back along {%.3f, %.3f, %.3f}\n", target, s, dir[0], dir[1], dir[2] );
  17.
                                                      } else
  18.
                                                              printf("s too big, ignoring\n");
  19.
                                              } else
  20.
                                                      printf("null, ignoring\n");
  21.
                                              //VectorCopy(eth.entities[target].head_visible_pt
  22.
                                      }