private int startX = -1;
    private int startY = -1;
    private void jPanel1MouseClicked(java.awt.event.MouseEvent evt) {

        if (startX == -1 && startY == -1){
            startX = evt.getX();
            startY = evt.getY();
        } else {
            Graphics g = this.jPanel1.getGraphics();

        int R=evt.getX()-startX; //nolasam radiusu, konvertejam no teksta uz veselu skaitli
        int pn=1-R; //risinosais parametrs x
        int wn=0;//tekosais un mainigais x
        int hn=R;//tekosais y
        while(wn<=hn){
            if(pn<0){
                wn++;//a.k.a wn=wn+1
                pn=pn+2*wn+1;
            }
            else{
                wn++;
                hn--;
                pn=pn+2*wn+1-2*hn;
            }

            g.drawRect(wn+startX,hn+startY,1,1);
            g.drawRect(-wn+startX,hn+startY,1,1);
            g.drawRect(wn+startX,-hn+startY,1,1);
            g.drawRect(-wn+startX,-hn+startY,1,1);
            g.drawRect(hn+startX,wn+startY,1,1);
            g.drawRect(-hn+startX,wn+startY,1,1);
            g.drawRect(-hn+startX,-wn+startY,1,1);
            g.drawRect(hn+startX,-wn+startY,1,1);
        }
            //g.drawLine(startX, startY, evt.getX(), evt.getY());
            //restartēt sākuma punktu
            startX = -1;
            startY = -1;
        }
    }