subroutine char SEGMENTS
 image erase
delete atom sele segm name #* end
key image sele .not all end

set col
sele segm name SEGMENTS .a weigh -1000. 0.0 end = 200
sele segm name SEGMENTS .a .n weigh -1000 0.0 end = 160
sele atom name H* .a by bond weigh 0.01 1111.0 end = 160
exit

image sele segment name SEGMENTS end set bond
image sele segment name SEGMENTS .a .not by bond all end atom cros
image sele segment name SEGMENTS end col 85 hbond
image sele t_anchor end col 200 atom cros
image sele t_anchor .o by pair t_anchor end col 200 bond
return

! the variance with a sphere around the current screen center
 key aro select by residue around center current dist 15. -
    .and segment name SEGMENTS end
image sele aro end set bond
image sele aro .a .not by bond all end atom cros
image sele aro end col 85 hbond
key image select aro .or. atom name CA end
key aro drop
return