void Triangle(double x1,double y1,double x2,double y2,double x3,double y3) {
    sprintf(outputbuffer,"\n %12.3f %12.3f m %12.3f %12.3f l %12.3f %12.3f l h",x1,y1,x2,y2,x3,y3);
    sendClean(outputbuffer);
}