private void sldSkalaStateChanged(javax.swing.event.ChangeEvent evt) {//GEN-FIRST:event_sldSkalaStateChanged
        if ( mainBoids.simul!=null){
         mainBoids.simul.setSkala(sldSkala.getValue()/2d);
        }
        this.lblSkala.setText("1 metr-"+Double.toString(sldSkala.getValue()/2d)+"px");
    }