spring_init (spring++, &model->objects[0], object, spacing);
for (j = 1; j < num_objects - i; j++) {
spacer_init (spacer++, object, object + j, spacing);
spring_init (spring++, &model->objects[0], object, spacing);
for (j = 1; j < num_objects - i; j++) {
spacer_init (spacer++, object, object + j, spacing);