Function ResetGroundObject

editor/HObject.cpp:429–474

Adjusts an object so it's at the ground level (for when the ground has moved)

// Adjusts an object so it's at the ground level (for when the ground has moved)
void ResetGroundObject(object *objp) {
  poly_model *pm;
  vector surface_norm;
  vector pos;
  matrix groundplane_orient, surface_orient, object_orient;

  // Make sure object is outside
  if (!OBJECT_OUTSIDE(objp)) {
    Int3(); // object is not outside
    return;
  }

  // Make sure object has a ground plane
  if (!((objp->render_type == RT_POLYOBJ) && ((pm = GetPolymodelPointer(objp->rtype.pobj_info.model_num))->n_ground))) {
    Int3(); // object doesn't have a ground plane
    return;
  }

  // Get terrain height and normal at current object location
  pos = objp->pos;
  pos.y = GetTerrainGroundPoint(&pos, &surface_norm);

  // Place the object's ground point on our placement point
  vector ground_point;
  vector ground_normal;
  vector to_ground;
  float dist;

  PhysCalcGround(&ground_point, &ground_normal, objp, 0);
  to_ground = objp->pos - ground_point;
  dist = ground_normal * to_ground;
  pos += dist * surface_norm;

  // Compute source and destination matrices
  vm_VectorToMatrix(&groundplane_orient, &pm->ground_slots[0].norm, NULL, NULL);
  vm_VectorToMatrix(&surface_orient, &surface_norm);

  // Compute orientation matrix
  vm_MatrixMulTMatrix(&object_orient, &surface_orient, &groundplane_orient);

  // Move the object
  ObjSetPos(objp, &pos, objp->roomnum, &object_orient, false);

  // Set flag
  World_changed = 1;
}

void HObjectMove(int objnum, float dx, float dy, float dz) {
  matrix *mat;