Hi Jeff, There is no watershed or flood-fill type of method in Chimera for segmenting volume data. This is on our (very long) list of features to develop though. Tom Jeff wrote:

tom,

i hate to keep piling on questions, but how hard would it be to have a feature where one places a chimera marker, and then has some sort of algorithm expand to 'fill' the space, kind of an isosurface problem (or does this already exist)

i have 'voids' in some of my maps (stained sections) which i think correspond to protein, like one sees in negative stain (the positive values/density in the map correspond to stain; an enclosed void (density more or less = 0 or close to it) is thought to represent the actual protein, which was covered in stain, kind of like 'magic shell' on ice cream - or think of dairy queen cone, dipped in chocolate that then solidifies), and would like some way to 'grow' a blob in the void (or at least try)

does this already exist? i have a buddy who does level set methods who is often looking for ways to use his library, but i thought i should ask you first if there is some functionality like this

-jeff