fix coverity report: rx ry and rx were not deleted in tgraph2d2
fix coverity report: rx ry and rx were not deleted in tgraph2d2

gganis/root,gganis/root,gganis/root,gganis/root,gganis/root,gganis/root,gganis/root,gganis/root,gganis/root,gganis/root,gganis/root