Free, open source molecular viewer and editor for protein structure, DNA structure, PDB, molecular rendering, biological macromolecule. Atoms may be drawn as spheres of different sizes. Bonds may be drawn as cylindrical sticks, conical sticks or as curved surfaces. Five types of slab are available: planar, spherical, semi-spherical, cylindrical and semi-cylindrical. The slab position and thickness are visible in a small window. Atomic bonds as well as atoms are treated as independent drawable objects. and more.