QTree is a program for generating CPK, Ball and Stick and worms pictures of molecules using the quad-tree algorithm. This is a relatively fast method of generating near-photographic quality images although it does not generate shadows. A sense of depth is provided by darkening atoms farther away from the viewer.

QTree provides many facilities including colouring by residue type, atom type, chain, temperature factor, or residue range, rotation, background colouring, modified lighting models and slabs through the structure. An interactive help facility is provided.

A unique feature of QTree is the ability to highlight a set of residues by drawing a line around them.

Output from the program is in MTV ray-tracer format which may be viewed or converted into other formats using the ImageMagick package. A version that produces PNG output will be released shortly.

The QTree package consists of the following programs:

The main rendering program producing CPK images by default.
A pre-processor to generate worms images.
A pre-processor to generate ball-and-stick or stick images.
A pre-processor used to generate images which mix CPK with ball-and-stick images.

You can read the README file before downloading.

QTree is listed in Linux Links Linux Links Logo



QTree is freely available for use by not-for-profit organisations and for commercial organisations (providing they inform the author that they are using it). It may not be distributed without the author's permission, but must be obtained from this site.


QTree is supplied as a gzipped tar file of source code.