ok…so you have a fish picture…what are you wanting to know…?
let me make a few comments on the picture…
if the white was metal and the back was cut out of the metal…the fish would fall away from the main piece of metal…as there are not any “bridges” between the white areas…
I used Inkscape to “trace to bitmap” your fish…and removed all the inside parts…this shows that there are not any links between the inside and outside …if the metal is the black then the iside of the fish will hall out.
and this would happen
so if you add “bridges” the inside will remain attached …bridges are the little black spaces that attach the inside to the outside…
is this making sense?